The real claim is 10 minute charging of lithium-ion batteries with a process which is a minor mod to existing battery production.
There's no product yet.
Batteries with good low temp behavior have many specialized uses.
Things that have a small solar panel, a battery, and no grid connection could benefit from this. Even flashlights could use this.
> Things that have a small solar panel, a battery, and no grid connection could benefit from this.
As a side topic, what are the currently available options for this?
I've heard about sodium ion (safer but still not sub-zero charging friendly, also no easily available solar charging controller boards), lithium titanate (same), and plain old deep-cycle lead acid.
For small solar-powered projects, it would be nice if there was a power bank on market which supported solar charging, and could either be safely charged in freezing temperatures, or had built-in temperature sensor and reject charging when it's too cold.
For completeness sake there are also many LifePo4 battery options that have heating pads that will activate below a certain temperature. Even Amazon have about a dozen brands with heating pads.
To answer the question look for "lifepo4" and "heated" [1] but it sounds like that's too big for your use case. In your case just use a regular and smaller deep cycle battery in a very waterproof enclosure. Bury the enclosure at least 6 feet under ground to keep it from falling below 50F / 9.9C without heating pads. At least 4 feet deep with 2 feet of gravel under the enclosure to keep water from pooling around the enclosure. Fill the bottom of the enclosure with desiccant pouches to absorb condensation. Use rodent-resistant cabling in conduits and a lot of sealant where the conduit is fastened to the enclosure. The enclosure should then be inside a rodent-proof vault. This could be pressure treated redwood or synthetic material rated for burial. Lay a foil marker in the hole above the vault and keep it centered as you bury the vault so that you can find it again.
Being under ground will prevent both over-heating and freezing assuming your circuit is per spec designed to run cool. This can also reduce tampering. If you are not concerned about serviceability of the circuit board then you can put it in a small enclosure and fill it with epoxy so that the entire thing is water proof. There are epoxies designed to conduct heat but not electricity.
This assumes of course that your setup is meant to be stationary.
I'm searching for "self heating power bank" on amazon.com and get various random crap (self heating lunch boxes, regular noname power banks, heating pad for pets...). Could you point me to some specific examples?
Thanks. These are a little big (100Ah, 200Ah, 50Ah...), heavy and expensive compared to what I'm looking for. For reference, I'm currently using a 5W panel, and a single 18650 element, costing a few dollars from AliExpress. Works fine for my usecase (Meshtastic nodes) except for the charging below 0°C thing.
At that scale you are probably better off building your own solution: a low-power microcontroller with a temperature sensor, a small heating element (search "heating foil"), some voltage sensing with the ADC on the battery and solar panels, and a bit of simple logic.
If you are mostly concerned with low-temperature charging you could even power all that from the charging side only.
At 5w, a simple temperature sensitive switch, 5w resistor, and some wraps of insulation might be enough. If below x temp, just shunt all current to the resistor, otherwise power the charger.
Not for cars yet, but Enovix has short-ion-path batteries intrinsic to its lithrographed 3D design. Performance is quite something: https://www.enovix.com/products/
The big news on EV charging is from BYD in late March when they announced (and it caused TSLA to fall by a few percent) that their new line of superchargers will be able to charge cars to give them a range of 400 km in just a few minutes. This is the state of the art in production
The state of the art (not just for BYD) is to make sure you don't have to charge a cold battery by getting it to the right temperature before charging. One of the reasons that Tesla (and others) has navigation integrated into trip planning integrated into the vehicle is so that the battery temperature can be optimized in the 10 minutes before you start charging, to maximize charging speed.
BYD would not pump 400 kW into a battery at -10 C. This research helps in the situation where you have a cold battery, and need to start charging it before it can warm up.
What does whole country consumption have to do with building megawatt chargers?
The problem isn't trivial. If you have, say, 10 charging spots on a lot, each requiring a megawatt, how are you going to deliver that? Are you going to build a whole substation for every charging parking lot?
They are expanding in Europe rapidly, and in China of course.
In the Netherlands they are partnered with a local green electricity provider (Vattenfall) and Shel for their charger network. Shell owns the most petrol stations along the highways, so they will have their chargers there for sure.
I'm expecting the tariffs on Chinese EVs to be rolled back in EU after the US tariffs. They might want BYD to open local factories, like NIO is planning to do.
> I'm expecting the tariffs on Chinese EVs to be rolled back in EU after the US tariffs.
I doubt it. This would likely have a significant negative impact on domestic EU car companies, most of which are considered cornerstones of their local country's economy. Now, whether this should happen (to benefit consumers/the environment) is another argument.
Then again, the most protective germany, has manoveured itself into a corner, with its production proxxy ungary loosing the "in-between-empires" heat gradient and annoying everyone.
Countries really need to stop unfairly penalizing Chinese EVs. If they aren't allowed to compete, local industries will never have an incentive to improve. No argument about safety has ever had any merit - Teslas burst into flames all the time.
There's a lot to unpack in your statement but China kneecaps their own purchasing of their goods in order to have cheap exports at the expense of their own civilians. Each country should act in the interest of their own civilians and industries. We can already see from Ukraine that having self-capability to produce your own weaponry is a good though. Producing vehicles is an aspect of that.
> If they aren't allowed to compete, local industries will never have an incentive to improve.
Neither Europe nor the US can compete with the level of disdain for the environment, labor laws and poverty that China brings to the table. Wages alone make anything made in China so cheap that, for mass-market goods, competing against China (or its upcoming competitors in the race to the bottom) is impossible.
> Neither Europe nor the US can compete with the level of disdain for the environment, labor laws and poverty that China brings to the table.
The issue is entirely subsidies at this point.
Labour costs have been steadily rising for the past decades and significant poverty hasn't been an issue for a long time. Emission wise, China is strictly ahead of the USA when you look per capita (unsurprisingly, they are not an oil producer).
China is not in a race to the bottom. Their hdi has been steadily climbing. They are economically more or less in the same position that Japan was in the 80s before the Plaza accord but with less prosperity, on the verge of becoming a developed country.
Which is a moot point because European manufacturers also received insane subsidies form their governments in the past.
The issue is China has been innovating in EVs hardcore for 15+ years while European manufactures kept pushing diesels and cutting costs with their suppliers and were only making EVs to shut up the green hippies, but were never committed to them, and now they've been caught with their pants down unable to compete on price nor on technology.
They got fat, lazy and complacent thinking their brand names would carry them.
> Which is a moot point because European manufacturers also received insane subsidies form their governments in the past.
There is no external arbiter here to call it even and declare it moot. The WTO was supposed to somewhat be that but has been completely defanged by non cooperation. Every country is sovereign regarding both how it subsidies its companies and how it taxes imports.
The European Union can both support its manufacturers and be unhappy about China doing the same.
> They got fat, lazy and complacent thinking their brand names would carry them.
Sure, but strategic inadequecy of the local companies doesn't necessarily prevent countries from wanting to protect their manufacturing sector. It's a lot of jobs from Germany and the value chain is split between a lot of small subcontractors injecting a lot of money in their local economy.
Having said that, the future is not necessarily a completely black and white alternative between punitive tariffs fully blocking more efficient Chinese companies à la Trump and a fully free market.
There is plenty of space for agreements involving companies partnership, partial technological transfers, bringing part of the value chain closer to the final consumer. China has been really smart at this game with the mandatory JV with a local partner for getting access to their market. Maybe it's time we start using the same playbook.
>Neither Europe nor the US can compete with the level of disdain for the environment, labor laws and poverty that China brings to the table
Why haven't western governments and companies brought this up as an issue when they moved our jobs to China 30 years ago forcing us to buy our stuff but made in China while their profits skyrocketed? And bear in mind Chinese pollution, wages and living standards were way worse back then than today.
It feels incredibly hypocritical for western companies to cry about these things NOW, right when the Chinese companies have started eating their lunch on their home turf, while they rode the gravy train for 30 years. It's almost as if they wanted to have their cake and eat it too but now have to reap what they sow and they don't like it.
> Why haven't western governments and companies brought this up as an issue when they moved our jobs to China 30 years ago forcing us to buy our stuff but made in China while their profits skyrocketed?
Our people loved it for the first few years because a lot of stuff became cheaper (or affordable at all), our governments loved it because now someone else would have to deal with toxic waste, and our companies and especially their owners made untold billions of profit that they were allowed to keep.
By the time China was strong enough to begin the "extinguish" phase of their 20 year economic plan, and the Western nations could no longer hide or deny the issues, it was far too late.
> It's almost as if they have to reap what they sow and they don't like it.
They do reap what they sow. The automotive industry is a victim of its own stupidity. They lobbied for features until the cars became so expensive that nobody buys them.
So what if someone living on Chinese wages wouldn't be able to afford American goods? The equivalent Chinese goods are perfectly affordable for them. You seemingly forget that China is a self-sufficient economy. It's not like people are working 16 hours a day to afford an apartment like in the US. Apartments in China can be as low as USD $400 a month or less. Try running your wage and poverty calculations with that?
It's not about price! As an example, China has had battery-swap stations for certain models of EV for years (see Nio). In just over a couple minutes (depending on the station), they automatically drop the battery out of the car and install a new one that is fully charged. It is even faster than DC charging in the US and Europe. But because those cars are either illegal or prohibitively expensive to import and use, there is no incentive for domestic industries to compete with it. As far as they're concerned, anything that makes a Chinese EV compelling is some sort of strategic threat against the US, rather than the product simply being better.
How cool would it be if instead of having to slowly charge the same battery in my EV over its lifetime, I could (say) subscribe to a network of well-kept batteries and easily get a fully-charged one whenever mine gets low? Too bad China is so out of reach for me; though even if it weren't, those battery-swap stations don't really exist here - though I'm sure that's just another artifact of widespread sinophobia.
That's only one example. See these article (or honestly any article) for more:
As an EV owner I just don't see the benefit in the battery swap method. I spend a lot of time monitoring my battery's health and keeping the cell balance from going too far out of line.
Maybe its short sighted of me, but I don't want some abused battery from another owner swapped into my EV. The amount of trust I'd have to place on a battery swap station to give me a battery that's just as reliable/healthy as my own managed battery is far too great. Would they just reject people who try to swap faulty battery's or just take it as an operational loss and recycle batteries that fall out of spec.
Of course a lot of this ties into future ownership/rental financial models, however the world works with everything going towards subscription in the future. If you're just subscription/leasing a car as a service the vast majority of people won't care of give a shit anyway.
As for now I own my EV and when the battery needs replacement ten years from now I expect to be able to buy another one, hopefully larger/more capable, and continue on my merry way.
That’s a false narrative about pricing. Battery manufacturing has a very low ratio of labor to cost.
Chinas secret ? Extremely protective tariffs + very selective smart RND incentives/ investments by government + biggest engineering pool in the world because of outsource to China due to free trade/ no tariffs in US/EU.
It’s a talent pool they built last ~20 years to do outsourcing/offshore policies
Yeah, would have thought if BYD played it smartly and the tech is that far ahead, they could get a lot of market share from batteries and chargers even if Europe's car brands remain strong and protected.
The battery can be large enough that it takes a long time to heat it, but that's usually what an EV is doing when it preconditions the battery for charging. My car (and pretty much all EVs) will precondition the battery if the next navigation stop is a charging station, for example.
This assumes that nav data is current or a telematics subscription is active. As Alec Watson of Tech Connections fame recently pointed out about his first-gen IONIQ 5, this needs to be feature accessible to the driver.
Even then, it still assumes that users understand that it is a problem in the first place and that they are willing to take steps to solve it.
For most people, a car is at least the second-most expensive thing they'll ever own -- as well as the most expensive machine they'll ever own. It is also something that many are very unwilling to RTFM for, often to the point of irately defending this unwillingness and the resultant ignorance.
An improved battery that can charge quickly when cold (while maintaining safety and longevity) solves many problems, including some that may be self-inflicted.
> it still assumes that users understand that it is a problem
3 decades ago everyone with a mobile phone knew that you should never charge the battery unless it's empty. They knew "it has memory" and if you charge it when it's half full it will "remember" that new charge as its capacity. A decade or so later with LiIon or LiPo everyone knew the opposite, never let it go to empty.
Nobody knew why, how, they just knew this is how you should do it.
This would work for EVs too because they're expensive to buy, expensive to replace batteries, and range or charging speed are super huge deals.
Except: In every practical application that Joe Average has ever experienced, the battery memory problem was only ever a mere myth. (A widely-parroted myth, but a myth nonetheless.)
I feel that your example portrays the opposite of what you may have intended it to portray.
What actually happened was that people went out of their way to do a thing that not only did not improve the overall longevity of their rechargeable batteries, but may have actually made it worse.
This might be "well ackshully" territory but the memory effect those NiCd/NiMH batteries were experiencing was very real but temporary. It could be fixed by doing a deep charge/discharge cycle for each cell. It worked great if you could use a smarter charger (I reconditioned so many cylindrical cell batteries like this), and was impossible when charging in the phone. Which made the temporary effect quite permanent.
Whatever you want to call it, the damage caused by certain usage patterns existed and was visible to the users. So they learned how to generally maintain the battery of that expensive device to keep it usable for longer. I have no reason to expect people are less capable to do the same for a car's battery, now that everyone is more tech educated and cars are smart enough to tell them what to do and when.
Right. That's still a thing that happens in series-wired batteries.
Voltage depression of individual cells seems to correlate more with deep discharges of a battery (perhaps combined with differences in cell quality within that battery) than anything else.
And deep discharges were what people were deliberately doing to fend off the evil spirits of "memory effect" probably made the problem worse.
Yeah, and this myth of never charging until empty has persisted through the 3 decades of the battery technology changes.
Not sure what would work for EVs too? I'd suggest education from the ev manufacturer is better (eg by repeating to the driver the first 50 times how and why to prepare for changing), and by the technical means (doint it automatically if possible).
Creating yet another "rule" that will then persist as the downright counterproductive or maybe even harmful myth decades later is not a good solution IMO.
> Even then, it still assumes that users understand that it is a problem in the first place and that they are willing to take steps to solve it.
No it doesn't. All it assumes is that some users may want to take steps to solve it and that those users deserve the option. Literally nothing needs to happen to the existing behavior, the automatic preconditioning can still stay.
Indeed. For example in most cars, if you decide to use the navigation from Apple's CarPlay or Google's, the vehicle will not pre-heat the battery before charging.
In my BMW EV we recently got an update and it's now possible to manually pre-heat the battery, not only from within the car, but also even remotely via app. You can even lookup now the battery temperature.
Yep, I refuse to pay for Ford's navigation. As of now neither carplay, nor android auto, can turn on battery preconditioning in my van. I've been monitoring the battery heater state in an app just in case it starts working in a future update. Recently an update finally allowed carplay to read my E-Transit's SOC when connected.
It would be nice if I could figure out some way to just force it on with a switch/aftermarket module talking to the canbus.
This pre-conditioning isn't free. It costs you range. So, doing less of that helps. And it takes time. The worst case for an EV is a short journey to a fast charger. Both heating the vehicle and the battery from ice cold takes energy.
Which the charging station has in spades. You should be able to run the heat pump at full bore when attached to a charger. And a regular heating element. Modern heat pumps have both, why not cars?
>You should be able to run the heat pump at full bore when attached to a charger.
That's how EV's currently work. Even those without heat pumps. I can see my E-transit's coolant heater[1] pull up to around ~5-6KW at full tilt battery heating mode when I plug into DC fast charging and its not sufficiently warmed. Cuts off once the HVB hits around 98F.
Many EVs (Teslas) already contain a heat pump to warm the battery. I presume that improved battery chemistry would supplement this -- but maybe replacement would be possible?
Not a battery expert but part of the challenge is too much heat in some places, not enough in others, so heat management is a big challenge, but coolant routing is complicated. The heat pump is a big deal and far more efficient (4x?) than a 'block heater', and resistance heat is the old solution that the industry moved away from.
I believe the "microscale channels" are a better solution that reduces the amount of heat generated at the connection points of the battery, and also reduces the high temperature gradient at high voltage charging at low internal temps (high internal temperature delta), which I understand to be a primary cause of battery degradation.
At least in my car, fully preconditioning the battery can take an hour or two when it's really cold. If you're still on the way to the charging station, it can also impact your range. My car is annoyingly conservative about when it uses and disabled the preconditioning
While the technology may be advantageous, it seems weird to write a whole article about it without mentioning the obvious solution: Just Heat The Battery. It's true that many early EVs (and most non-Teslas even today) don't ship with battery thermal management. But they won't be getting new battery chemistry either.
This is one of those Great New Technology items that smells like a failure simply because it's not competing with the thing the designers think it is. It's not enough for this to beat a cold battery with a performance delta ("5x", per the article) that would justify its additional cost. It has to beat a battery with a garden variety heat pump attached, which is a much (much) lower cost barrier.
In winter, I lose 5-10% of my battery a day due to heating my battery. Tesla is nice enough to hide this under "You should keep your car plugged in all the time" messages. It's really a pain, especially if you have a relatively small battery to begin with. I have a 2019 Model 3 w/ a 50 kwh battery, and use 10-20 kwh on a regular basis; 5 kwh wasted means as much as 1/3 of my energy use is effectively waste.
I'd be very interested in seeing what they can provide for us. Improved battery chemistry for use in the far north is of far, far more value than yet another 5 person car for 1 person driving in San Francisco.
When I bought a Model 3 last year I knew full well the issues with charging, temperature capacity loss, battery heating, etc. What I was surprised by was loss of regen! If the battery is below 20F or so then the firmware will only give it a trickle of regen braking. After all, it's effectively very fast charging, which a frozen battery can't handle.
I wonder if regen braking going to zero is behind some of the horror stories of sudden unexpected range loss in cold temps.
> In winter, I lose 5-10% of my battery a day due to heating my battery.
Exactly! That sounds like a drawback when you state it like that, but what it actually means is that this magic battery doodad needs to provide 90-95% of the performance of its existing, mature competitor (assuming no other drawbacks) just to be break-even in the market. You don't disrupt markets with numbers like that.
> what it actually means is that this magic battery doodad needs to provide 90-95% of the performance of its existing, mature competitor
The problem is mostly that it does the battery draw when parked.
Solid electrolytes are coming some day soon, so that we can let it freeze without killing the cells.
Right now, the Tesla is hard to use in a winter sport season unless where you're driving has a charger or underground parking near a plug point.
I can drive up hill to a nice ski resort, spend 3+ days taking the bus with all your shoes on without touching the car.
With the batteries, they'll just run down when parked, so I cannot park it for a whole week outdoors like I can do with my Subaru.
And with the low battery + low temps, it will not charge back up going downhill so the expected range drops massively by the time you're downhill.
Once you navigate to a charger, the car starts running the heater and driving down range further.
Watching the car battery eating its own range while driving to "Donner pass road" on your way out of Tahoe or Reno feels rather appropriately horrific.
I can't speak for a modern subaru, but I've not owned a single ICE vehicle that would work in this scenario. The battery would be dead. An electric one has the option to be plugged in and avoid the problem. Just because we haven't put the infrastructure in place for it doesn't mean we can't. We should do so, just like we did for gasoline.
If your ICE car battery was dead after sitting a week in the cold you had a bad battery. I drive my car once every couple weeks and it regularly gets to -20 here in the winter and have never had an issue because the battery in my ICE vehicle is good.
What kind of clunkers have you been using that lose charge on the 12 volt after just 3 days in the cold? I've occasionally left my ICE car out in the cold for a week without using it and it never once even crossed my mind to worry about whether it would start after that; I've never had that issue on any car built in the last 15 years.
My 2022 Volkswagen e-Up has zero thermal management of the battery, it's completely passively cooled with no heating. Not that it really matters, people have tested it and charging speed only starts to degrade after 3-4 rapid charges in one day, with "rapid" in quotes(in tops out at 40kW).
I believe the eGolf which was sold in the US shares the same drivetrain and battery.
Almost all non-Tesla EVs offer a heat pump option. Most non-Tesla EVs sold do not have one. Just go to your local VW dealer or whatever and see what the specs are on the ID.4's on the lot is.
You can easily read about your example VW MEB platform battery configurations, including built in thermal management system, online at the Munro teardown, for example.
Perhaps you are changing the topic from your original thermal management to heat pump systems specifically?
Heating, in its various forms, has one big drawback that having a battery that can charge faster in low temps would be really nice in: Starting the day needing to charge.
Ideally, you don't do that, but when traveling sometimes you have to stay at a place that doesn't have a charger, and it's really cold, and now rather than a 30 minute charge it's more like 90 minutes.
You don't even need a heat pump. You can just slightly overvolt the charger, so that some electrical energy is lost as heat rather get than transformed into chemical bonds.
> This is one of those Great New Technology items that smells like a failure simply because it's not competing with the thing the designers think it is.
This technology makes no sense for fast DC charging because there's enough waste heat to keep up the battery temperature, and you can just use some of the power to heat up the battery.
But it can help for slow overnight charging. Keeping battery heated all night is wasteful, but you still want to be able to charge.
That doesn’t work when the problem is the battery is already sub-zero - lithium plating occurs when trying to charge in those conditions, destroying the battery.
You can’t just overvolt out of that - you need an external source of heat until you’re out of the dangerous thermal area.
I'm not sure if that affects all chemistries and compositions. If you look at the spec-sheet for e.g. the LG E63 cells used in some older EVs (notably without TMS), those specify charging down to -20 °C - and the owner's manuals certainly have no warnings in them that the car will implode if you charge in the winter.
At least not in a way that people complain about battery failures or degradation. On the other hand, the battery has to reach that temperature in the first place, which may take a couple days of constant exposure to that temperature.
Actually, it does and will in the right conditions. Look at page 11 of that link.
I did some research, and the plating issue happens when charge currents exceed the ability for the battery to absorb them, which dramatically decreases below freezing.
That is why those battery charts show dramatically reduced charge currents (nearly zero) when around freezing.
That data sheet also doesn’t cover cell life in these conditions conditions.
They have very high normal C ratings (hundreds of amps) which is why it is measurable and not actually zero, but reducing it to a couple amps before failure isn’t much different.
If batteries aren’t failing in these conditions, it’s because of some other protective circuit, not because the battery itself is special. It isn’t.
> You don't even need a heat pump. You can just slightly overvolt the charger
The BMW i3 had inductive heating strips underneath the coolant channels in the battery pack[1]. I know our i3 had a heat pump, I presume both were in play.
We used our i3 down to -25C (-13F) many times, didn't have any issues.
I mean this is an incremental improvement that would be very welcome. Why be so negative? Look around the products that have lived through decades of incremental improvements and compare them. Like the phone in your pocket or computer you are using.
Heat pumps struggle to do much at the temperature range the article proposes.
Edit: downvote me all you want, I was responding specifically to “It has to beat a battery with a garden variety heat pump attached” of which EV heat pumps are not garden variety heat pumps, which do struggle at those temperatures. Didn’t think I had to be so pedantic.
Pretty sure the ones in most EVs today work fine at -10C, but they may lose some efficiency. The thing is, there's already mechanisms in some cars to generate waste heat specifically for this purpose. Tesla's already have the ability to run their motors 'inefficiently' generating waste heat, which can be pumped into the battery coolant and heat that. It's no better than electric strip heating, but it doesn't add any cost to the system.
The real benefit, in my view, to being able to charge at cold temps is to improve overall efficiency. If you have to waste some amount of power to heat the battery then that is power that could have been used to charge the car instead...
You bring up a great point. The battery spec is only given at -10C. That's a mild normal day's low temperature in winter in Minneapolis, USA. But it's often much colder than that for long periods of time. I wonder if this glassy layer they apply can handle -30C; a temp where above ground heat pumps are no better than electrical resistive heating.
The 5x delta is stated to be at 14F. That absolutely is within the reasonable operating range of a Model Y heat pump, not sure what you're citing?
It's true that there are very cold environments (Fairbanks winters, say) where in-car thermal management won't be sufficient to keep charging rates high. But those are the same environments where you can't even start a gasoline car without an engine block heater, and I don't see many "no cars in Alaska" arguments on the internet. Everything has limits, but I don't see this battery trickery having much of a home.
You can start gasoline cars just fine down to 20 or 30 below, so long as you keep a good battery in it. Sometimes big diesel trucks use block heaters but gasoline cars don't need them.
I live in a region where -40°C is not unheard of (it happens every winter and stays for up to several weeks). I've also been to another region (not far off) where -50°C is pretty typical.
Gasoline powered engines work just fine in these temperatures, although many cars come with auto ignition systems that start up the engine periodically throughout the night to keep it warm. Otherwise you might have to warm it yourself in the morning using a gasoline powered "torch" (or whatever it's called), which sometimes ends up with the car going up in flames.
So it's honestly pretty funny to read that EV work "down to -10°C". Although probably relatively few of us are desperate enough to be living in such conditions.
Stock gasoline cars do not do well at those temperatures. In Alaska most people with sense use engine block heaters, plugging in every cold night. Besides the issue of having trouble just starting the car, you will put excessive wear and tear on the engine doing it regularly.
And in places like Fairbanks where -40 (F/C) is fairly common in the winter, even cars that merely have an engine block heater will have trouble. You need even more heating pads for the rest of the stuff under the hood of you want to keep a car reliable and healthy in that kind of climate.
Only if they have the ability to stop charging if the battery pack is below freezing, and some way to heat the pack (and keep it) above freezing. Otherwise, charging in those temps will destroy the battery.
I've succesfully started my rustbucket diesel from 2009 in -33C. It didn't sound too happy about it, but it did start and run and get to where I wanted
I can definitely say that old/USSR 2.7L gasoline engines for the military came with block heaters. But they were expected to start in -50C / -60F. Good luck getting anything out of an EV at those temperatures.
There's plenty of Norwegians on YouTube testing EVs down to those kinds of temperatures and they work absolutely fine, with the caveat that they won't charge until the battery warms up. Discharging Lithium batteries at really low temperatures isn't an issue, charging them is(because it actively damages them) - but even then the threshold is -32C or around that, easily overcome even with a simple resistive heater.
Norway is not "those kind of temperatures". They get a lot of snow, and maybe -5C and that is all because Gulfstream (the reason Murmansk does not freeze, and it's much farther into Arctic). Otherwise they get it easy.
Now when you move just a bit off the sea, the continental climate kicks in, and you have weeks of -15 -- -20C.
On discharging lithium chemistries at those temperatures or "easily overcame with resistive" let me say that: you just don't know what you are talking about.
The question is, how many people are legitimately living in areas where this is an actual concern in their lives? Outside of Alaska, Canada and Russia barely any place on Earth that relevant amounts of people live in, such low temperatures are a once-in-a-lifetime event.
it seems a little bit dubious to me. You can't beat the Arrhenius Law, not in Electrochemistry, anyhow. The ion mobility would be very very low, you'd have to rely that the temperature in the battery itself is above 0°C
Nice to see that they require minimal changes at the battery manufacturer. Too often people come up with good ideas like this without accounting for other factors in the supply chain.
Company web site.[1]
The real claim is 10 minute charging of lithium-ion batteries with a process which is a minor mod to existing battery production.
There's no product yet.
Batteries with good low temp behavior have many specialized uses. Things that have a small solar panel, a battery, and no grid connection could benefit from this. Even flashlights could use this.
[1] http://arborbatteries.us/
> Things that have a small solar panel, a battery, and no grid connection could benefit from this.
As a side topic, what are the currently available options for this?
I've heard about sodium ion (safer but still not sub-zero charging friendly, also no easily available solar charging controller boards), lithium titanate (same), and plain old deep-cycle lead acid.
For small solar-powered projects, it would be nice if there was a power bank on market which supported solar charging, and could either be safely charged in freezing temperatures, or had built-in temperature sensor and reject charging when it's too cold.
Most consumer LiFePO4 power stations have this sensor and cut charging below 0C, still allowing discharge up to around -10C.
For completeness sake there are also many LifePo4 battery options that have heating pads that will activate below a certain temperature. Even Amazon have about a dozen brands with heating pads.
Can you point to any specific examples? Do they support solar charging? And what wattage panel would be needed to support both charging and heating?
To answer the question look for "lifepo4" and "heated" [1] but it sounds like that's too big for your use case. In your case just use a regular and smaller deep cycle battery in a very waterproof enclosure. Bury the enclosure at least 6 feet under ground to keep it from falling below 50F / 9.9C without heating pads. At least 4 feet deep with 2 feet of gravel under the enclosure to keep water from pooling around the enclosure. Fill the bottom of the enclosure with desiccant pouches to absorb condensation. Use rodent-resistant cabling in conduits and a lot of sealant where the conduit is fastened to the enclosure. The enclosure should then be inside a rodent-proof vault. This could be pressure treated redwood or synthetic material rated for burial. Lay a foil marker in the hole above the vault and keep it centered as you bury the vault so that you can find it again.
Being under ground will prevent both over-heating and freezing assuming your circuit is per spec designed to run cool. This can also reduce tampering. If you are not concerned about serviceability of the circuit board then you can put it in a small enclosure and fill it with epoxy so that the entire thing is water proof. There are epoxies designed to conduct heat but not electricity.
This assumes of course that your setup is meant to be stationary.
[1] - https://www.amazon.com/s?field-keywords=lifepo4+heated
Just look for ‘self heating’
I'm searching for "self heating power bank" on amazon.com and get various random crap (self heating lunch boxes, regular noname power banks, heating pad for pets...). Could you point me to some specific examples?
Self heating lithium iron phosphate battery [https://battlebornbatteries.com/shop/products/batteries/heat...]
Thanks. These are a little big (100Ah, 200Ah, 50Ah...), heavy and expensive compared to what I'm looking for. For reference, I'm currently using a 5W panel, and a single 18650 element, costing a few dollars from AliExpress. Works fine for my usecase (Meshtastic nodes) except for the charging below 0°C thing.
At that scale you are probably better off building your own solution: a low-power microcontroller with a temperature sensor, a small heating element (search "heating foil"), some voltage sensing with the ADC on the battery and solar panels, and a bit of simple logic.
If you are mostly concerned with low-temperature charging you could even power all that from the charging side only.
At 5w, a simple temperature sensitive switch, 5w resistor, and some wraps of insulation might be enough. If below x temp, just shunt all current to the resistor, otherwise power the charger.
According to this sodium ion battery product, it still charge quite happily at -20 degrees C:
https://midsummerwholesale.co.uk/buy/eleven-energy/4-5-kwh-s...
Not for cars yet, but Enovix has short-ion-path batteries intrinsic to its lithrographed 3D design. Performance is quite something: https://www.enovix.com/products/
The big news on EV charging is from BYD in late March when they announced (and it caused TSLA to fall by a few percent) that their new line of superchargers will be able to charge cars to give them a range of 400 km in just a few minutes. This is the state of the art in production
https://www.ttnews.com/articles/byd-5-minute-charging-rivals
The state of the art (not just for BYD) is to make sure you don't have to charge a cold battery by getting it to the right temperature before charging. One of the reasons that Tesla (and others) has navigation integrated into trip planning integrated into the vehicle is so that the battery temperature can be optimized in the 10 minutes before you start charging, to maximize charging speed.
BYD would not pump 400 kW into a battery at -10 C. This research helps in the situation where you have a cold battery, and need to start charging it before it can warm up.
That requires 1 megawatt chargers. For each charger.
Not saying it's impossible, but that won't be easy.
The US consumes 376 million gallons of gas per day. Which is equivalent to a continuous power draw of 500 gigawatts.
Megawatt chargers? We'll need the generation capacity to support 500,000 of them.
What does whole country consumption have to do with building megawatt chargers?
The problem isn't trivial. If you have, say, 10 charging spots on a lot, each requiring a megawatt, how are you going to deliver that? Are you going to build a whole substation for every charging parking lot?
I mean, this is great, but BYD has pretty much zero installed charger footprint in markets where the Supercharger network exists.
Is that going to change?
They are expanding in Europe rapidly, and in China of course.
In the Netherlands they are partnered with a local green electricity provider (Vattenfall) and Shel for their charger network. Shell owns the most petrol stations along the highways, so they will have their chargers there for sure.
I'm expecting the tariffs on Chinese EVs to be rolled back in EU after the US tariffs. They might want BYD to open local factories, like NIO is planning to do.
> I'm expecting the tariffs on Chinese EVs to be rolled back in EU after the US tariffs.
I doubt it. This would likely have a significant negative impact on domestic EU car companies, most of which are considered cornerstones of their local country's economy. Now, whether this should happen (to benefit consumers/the environment) is another argument.
> I doubt it. This would likely have a significant negative impact on domestic EU car companies
They want to pair that with technology transfers, similar to how China forced other companies to do technology transfers when opening factories.
Then again, the most protective germany, has manoveured itself into a corner, with its production proxxy ungary loosing the "in-between-empires" heat gradient and annoying everyone.
Considering current politics: not in the US, at least not for the foreseeable future.
Europe remains to be seen, but also unlikely short term as we're also slapping lots of tariffs on chinese EVs to protect local industries
Countries really need to stop unfairly penalizing Chinese EVs. If they aren't allowed to compete, local industries will never have an incentive to improve. No argument about safety has ever had any merit - Teslas burst into flames all the time.
There's a lot to unpack in your statement but China kneecaps their own purchasing of their goods in order to have cheap exports at the expense of their own civilians. Each country should act in the interest of their own civilians and industries. We can already see from Ukraine that having self-capability to produce your own weaponry is a good though. Producing vehicles is an aspect of that.
> If they aren't allowed to compete, local industries will never have an incentive to improve.
Neither Europe nor the US can compete with the level of disdain for the environment, labor laws and poverty that China brings to the table. Wages alone make anything made in China so cheap that, for mass-market goods, competing against China (or its upcoming competitors in the race to the bottom) is impossible.
> Neither Europe nor the US can compete with the level of disdain for the environment, labor laws and poverty that China brings to the table.
The issue is entirely subsidies at this point.
Labour costs have been steadily rising for the past decades and significant poverty hasn't been an issue for a long time. Emission wise, China is strictly ahead of the USA when you look per capita (unsurprisingly, they are not an oil producer).
China is not in a race to the bottom. Their hdi has been steadily climbing. They are economically more or less in the same position that Japan was in the 80s before the Plaza accord but with less prosperity, on the verge of becoming a developed country.
>The issue is entirely subsidies at this point.
Which is a moot point because European manufacturers also received insane subsidies form their governments in the past.
The issue is China has been innovating in EVs hardcore for 15+ years while European manufactures kept pushing diesels and cutting costs with their suppliers and were only making EVs to shut up the green hippies, but were never committed to them, and now they've been caught with their pants down unable to compete on price nor on technology.
They got fat, lazy and complacent thinking their brand names would carry them.
> Which is a moot point because European manufacturers also received insane subsidies form their governments in the past.
There is no external arbiter here to call it even and declare it moot. The WTO was supposed to somewhat be that but has been completely defanged by non cooperation. Every country is sovereign regarding both how it subsidies its companies and how it taxes imports.
The European Union can both support its manufacturers and be unhappy about China doing the same.
> They got fat, lazy and complacent thinking their brand names would carry them.
Sure, but strategic inadequecy of the local companies doesn't necessarily prevent countries from wanting to protect their manufacturing sector. It's a lot of jobs from Germany and the value chain is split between a lot of small subcontractors injecting a lot of money in their local economy.
Having said that, the future is not necessarily a completely black and white alternative between punitive tariffs fully blocking more efficient Chinese companies à la Trump and a fully free market.
There is plenty of space for agreements involving companies partnership, partial technological transfers, bringing part of the value chain closer to the final consumer. China has been really smart at this game with the mandatory JV with a local partner for getting access to their market. Maybe it's time we start using the same playbook.
>Neither Europe nor the US can compete with the level of disdain for the environment, labor laws and poverty that China brings to the table
Why haven't western governments and companies brought this up as an issue when they moved our jobs to China 30 years ago forcing us to buy our stuff but made in China while their profits skyrocketed? And bear in mind Chinese pollution, wages and living standards were way worse back then than today.
It feels incredibly hypocritical for western companies to cry about these things NOW, right when the Chinese companies have started eating their lunch on their home turf, while they rode the gravy train for 30 years. It's almost as if they wanted to have their cake and eat it too but now have to reap what they sow and they don't like it.
> Why haven't western governments and companies brought this up as an issue when they moved our jobs to China 30 years ago forcing us to buy our stuff but made in China while their profits skyrocketed?
Our people loved it for the first few years because a lot of stuff became cheaper (or affordable at all), our governments loved it because now someone else would have to deal with toxic waste, and our companies and especially their owners made untold billions of profit that they were allowed to keep.
By the time China was strong enough to begin the "extinguish" phase of their 20 year economic plan, and the Western nations could no longer hide or deny the issues, it was far too late.
> It's almost as if they have to reap what they sow and they don't like it.
They do reap what they sow. The automotive industry is a victim of its own stupidity. They lobbied for features until the cars became so expensive that nobody buys them.
> They lobbied for features until the cars became so expensive that nobody buys them.
Dealerships still try to sell people on financing and that makes them so much money.
So what if someone living on Chinese wages wouldn't be able to afford American goods? The equivalent Chinese goods are perfectly affordable for them. You seemingly forget that China is a self-sufficient economy. It's not like people are working 16 hours a day to afford an apartment like in the US. Apartments in China can be as low as USD $400 a month or less. Try running your wage and poverty calculations with that?
China has lower levels of extreme poverty than the US: https://en.wikipedia.org/wiki/List_of_countries_by_percentag... (percentage living off of less than 2.65USD a day).
They also have lower per capita emissions than the US: https://en.wikipedia.org/wiki/List_of_countries_by_carbon_di...
Hm , in China you can’t buy any foreign made car without 70-90% taxes. That’s exactly how they built their industry
Nothing unfair about it, it is easy to build a car for cheaper if you don't care about worker rights and the environment.
It's not about price! As an example, China has had battery-swap stations for certain models of EV for years (see Nio). In just over a couple minutes (depending on the station), they automatically drop the battery out of the car and install a new one that is fully charged. It is even faster than DC charging in the US and Europe. But because those cars are either illegal or prohibitively expensive to import and use, there is no incentive for domestic industries to compete with it. As far as they're concerned, anything that makes a Chinese EV compelling is some sort of strategic threat against the US, rather than the product simply being better.
How cool would it be if instead of having to slowly charge the same battery in my EV over its lifetime, I could (say) subscribe to a network of well-kept batteries and easily get a fully-charged one whenever mine gets low? Too bad China is so out of reach for me; though even if it weren't, those battery-swap stations don't really exist here - though I'm sure that's just another artifact of widespread sinophobia.
That's only one example. See these article (or honestly any article) for more:
https://www.investors.com/news/chinese-electric-cars-america...
https://www.carwow.co.uk/electric-cars/chinese
Dismiss it as propaganda if you wish, but it's not like it's fake. The cars they show are real.
As an EV owner I just don't see the benefit in the battery swap method. I spend a lot of time monitoring my battery's health and keeping the cell balance from going too far out of line.
Maybe its short sighted of me, but I don't want some abused battery from another owner swapped into my EV. The amount of trust I'd have to place on a battery swap station to give me a battery that's just as reliable/healthy as my own managed battery is far too great. Would they just reject people who try to swap faulty battery's or just take it as an operational loss and recycle batteries that fall out of spec.
Of course a lot of this ties into future ownership/rental financial models, however the world works with everything going towards subscription in the future. If you're just subscription/leasing a car as a service the vast majority of people won't care of give a shit anyway.
As for now I own my EV and when the battery needs replacement ten years from now I expect to be able to buy another one, hopefully larger/more capable, and continue on my merry way.
That’s a false narrative about pricing. Battery manufacturing has a very low ratio of labor to cost.
Chinas secret ? Extremely protective tariffs + very selective smart RND incentives/ investments by government + biggest engineering pool in the world because of outsource to China due to free trade/ no tariffs in US/EU.
It’s a talent pool they built last ~20 years to do outsourcing/offshore policies
Isn't their plan to sell them to charger operators?
Yeah, would have thought if BYD played it smartly and the tech is that far ahead, they could get a lot of market share from batteries and chargers even if Europe's car brands remain strong and protected.
How much more expensive will this solution be than putting a “block heater” into the battery to warm it up to room temperature faster while charging?
If the charge rate is reduced by battery temp and chemistry, shunt the surplus supply into changing the battery temp, no?
The battery can be large enough that it takes a long time to heat it, but that's usually what an EV is doing when it preconditions the battery for charging. My car (and pretty much all EVs) will precondition the battery if the next navigation stop is a charging station, for example.
This assumes that nav data is current or a telematics subscription is active. As Alec Watson of Tech Connections fame recently pointed out about his first-gen IONIQ 5, this needs to be feature accessible to the driver.
Even then, it still assumes that users understand that it is a problem in the first place and that they are willing to take steps to solve it.
For most people, a car is at least the second-most expensive thing they'll ever own -- as well as the most expensive machine they'll ever own. It is also something that many are very unwilling to RTFM for, often to the point of irately defending this unwillingness and the resultant ignorance.
An improved battery that can charge quickly when cold (while maintaining safety and longevity) solves many problems, including some that may be self-inflicted.
> it still assumes that users understand that it is a problem
3 decades ago everyone with a mobile phone knew that you should never charge the battery unless it's empty. They knew "it has memory" and if you charge it when it's half full it will "remember" that new charge as its capacity. A decade or so later with LiIon or LiPo everyone knew the opposite, never let it go to empty.
Nobody knew why, how, they just knew this is how you should do it.
This would work for EVs too because they're expensive to buy, expensive to replace batteries, and range or charging speed are super huge deals.
Except: In every practical application that Joe Average has ever experienced, the battery memory problem was only ever a mere myth. (A widely-parroted myth, but a myth nonetheless.)
I feel that your example portrays the opposite of what you may have intended it to portray.
What actually happened was that people went out of their way to do a thing that not only did not improve the overall longevity of their rechargeable batteries, but may have actually made it worse.
This might be "well ackshully" territory but the memory effect those NiCd/NiMH batteries were experiencing was very real but temporary. It could be fixed by doing a deep charge/discharge cycle for each cell. It worked great if you could use a smarter charger (I reconditioned so many cylindrical cell batteries like this), and was impossible when charging in the phone. Which made the temporary effect quite permanent.
Whatever you want to call it, the damage caused by certain usage patterns existed and was visible to the users. So they learned how to generally maintain the battery of that expensive device to keep it usable for longer. I have no reason to expect people are less capable to do the same for a car's battery, now that everyone is more tech educated and cars are smart enough to tell them what to do and when.
Right. That's still a thing that happens in series-wired batteries.
Voltage depression of individual cells seems to correlate more with deep discharges of a battery (perhaps combined with differences in cell quality within that battery) than anything else.
And deep discharges were what people were deliberately doing to fend off the evil spirits of "memory effect" probably made the problem worse.
Yeah, and this myth of never charging until empty has persisted through the 3 decades of the battery technology changes.
Not sure what would work for EVs too? I'd suggest education from the ev manufacturer is better (eg by repeating to the driver the first 50 times how and why to prepare for changing), and by the technical means (doint it automatically if possible).
Creating yet another "rule" that will then persist as the downright counterproductive or maybe even harmful myth decades later is not a good solution IMO.
The general population is now more tech literate than a couple of decades ago. They’ll be fine.
> Even then, it still assumes that users understand that it is a problem in the first place and that they are willing to take steps to solve it.
No it doesn't. All it assumes is that some users may want to take steps to solve it and that those users deserve the option. Literally nothing needs to happen to the existing behavior, the automatic preconditioning can still stay.
People who experience range anxiety have an internalized incentive to seek out these options.
Indeed. For example in most cars, if you decide to use the navigation from Apple's CarPlay or Google's, the vehicle will not pre-heat the battery before charging.
In my BMW EV we recently got an update and it's now possible to manually pre-heat the battery, not only from within the car, but also even remotely via app. You can even lookup now the battery temperature.
Yep, I refuse to pay for Ford's navigation. As of now neither carplay, nor android auto, can turn on battery preconditioning in my van. I've been monitoring the battery heater state in an app just in case it starts working in a future update. Recently an update finally allowed carplay to read my E-Transit's SOC when connected.
It would be nice if I could figure out some way to just force it on with a switch/aftermarket module talking to the canbus.
This pre-conditioning isn't free. It costs you range. So, doing less of that helps. And it takes time. The worst case for an EV is a short journey to a fast charger. Both heating the vehicle and the battery from ice cold takes energy.
Which the charging station has in spades. You should be able to run the heat pump at full bore when attached to a charger. And a regular heating element. Modern heat pumps have both, why not cars?
>You should be able to run the heat pump at full bore when attached to a charger.
That's how EV's currently work. Even those without heat pumps. I can see my E-transit's coolant heater[1] pull up to around ~5-6KW at full tilt battery heating mode when I plug into DC fast charging and its not sufficiently warmed. Cuts off once the HVB hits around 98F.
[1]https://www.proxyparts.com/car-parts-stock/information/part-...
Many EVs (Teslas) already contain a heat pump to warm the battery. I presume that improved battery chemistry would supplement this -- but maybe replacement would be possible?
https://www.youtube.com/watch?v=DyGgrkeds5U
Not only Teslas: my Renault has this as standard, and many brands have it at least as an option.
Tesla already heats the battery in this way- it essentially just puts opposing fields into the motor to generate excess heat even when not moving.
https://electrek.co/2017/08/24/tesla-model-3-exclusive-batte...
Not a battery expert but part of the challenge is too much heat in some places, not enough in others, so heat management is a big challenge, but coolant routing is complicated. The heat pump is a big deal and far more efficient (4x?) than a 'block heater', and resistance heat is the old solution that the industry moved away from.
I believe the "microscale channels" are a better solution that reduces the amount of heat generated at the connection points of the battery, and also reduces the high temperature gradient at high voltage charging at low internal temps (high internal temperature delta), which I understand to be a primary cause of battery degradation.
At least in my car, fully preconditioning the battery can take an hour or two when it's really cold. If you're still on the way to the charging station, it can also impact your range. My car is annoyingly conservative about when it uses and disabled the preconditioning
Link to the research article: https://www.cell.com/joule/abstract/S2542-4351(25)00062-5
While the technology may be advantageous, it seems weird to write a whole article about it without mentioning the obvious solution: Just Heat The Battery. It's true that many early EVs (and most non-Teslas even today) don't ship with battery thermal management. But they won't be getting new battery chemistry either.
This is one of those Great New Technology items that smells like a failure simply because it's not competing with the thing the designers think it is. It's not enough for this to beat a cold battery with a performance delta ("5x", per the article) that would justify its additional cost. It has to beat a battery with a garden variety heat pump attached, which is a much (much) lower cost barrier.
In winter, I lose 5-10% of my battery a day due to heating my battery. Tesla is nice enough to hide this under "You should keep your car plugged in all the time" messages. It's really a pain, especially if you have a relatively small battery to begin with. I have a 2019 Model 3 w/ a 50 kwh battery, and use 10-20 kwh on a regular basis; 5 kwh wasted means as much as 1/3 of my energy use is effectively waste.
I'd be very interested in seeing what they can provide for us. Improved battery chemistry for use in the far north is of far, far more value than yet another 5 person car for 1 person driving in San Francisco.
When I bought a Model 3 last year I knew full well the issues with charging, temperature capacity loss, battery heating, etc. What I was surprised by was loss of regen! If the battery is below 20F or so then the firmware will only give it a trickle of regen braking. After all, it's effectively very fast charging, which a frozen battery can't handle.
I wonder if regen braking going to zero is behind some of the horror stories of sudden unexpected range loss in cold temps.
> In winter, I lose 5-10% of my battery a day due to heating my battery.
Exactly! That sounds like a drawback when you state it like that, but what it actually means is that this magic battery doodad needs to provide 90-95% of the performance of its existing, mature competitor (assuming no other drawbacks) just to be break-even in the market. You don't disrupt markets with numbers like that.
> what it actually means is that this magic battery doodad needs to provide 90-95% of the performance of its existing, mature competitor
The problem is mostly that it does the battery draw when parked.
Solid electrolytes are coming some day soon, so that we can let it freeze without killing the cells.
Right now, the Tesla is hard to use in a winter sport season unless where you're driving has a charger or underground parking near a plug point.
I can drive up hill to a nice ski resort, spend 3+ days taking the bus with all your shoes on without touching the car.
With the batteries, they'll just run down when parked, so I cannot park it for a whole week outdoors like I can do with my Subaru.
And with the low battery + low temps, it will not charge back up going downhill so the expected range drops massively by the time you're downhill.
Once you navigate to a charger, the car starts running the heater and driving down range further.
Watching the car battery eating its own range while driving to "Donner pass road" on your way out of Tahoe or Reno feels rather appropriately horrific.
I can't speak for a modern subaru, but I've not owned a single ICE vehicle that would work in this scenario. The battery would be dead. An electric one has the option to be plugged in and avoid the problem. Just because we haven't put the infrastructure in place for it doesn't mean we can't. We should do so, just like we did for gasoline.
If your ICE car battery was dead after sitting a week in the cold you had a bad battery. I drive my car once every couple weeks and it regularly gets to -20 here in the winter and have never had an issue because the battery in my ICE vehicle is good.
that, or you have some broken thing connected that draws way to high idle current.
???
What kind of clunkers have you been using that lose charge on the 12 volt after just 3 days in the cold? I've occasionally left my ICE car out in the cold for a week without using it and it never once even crossed my mind to worry about whether it would start after that; I've never had that issue on any car built in the last 15 years.
There are entire nations where this is the scenario all winter.
> It's true that many early EVs (and most non-Teslas even today) don't ship with battery thermal management.
That’s false since at latest 2013 in the US.
The past 12 years of BMW as a counterexample all have thermal management. Tesla too.
You may be remembering the original Nissan Leaf?
My 2022 Volkswagen e-Up has zero thermal management of the battery, it's completely passively cooled with no heating. Not that it really matters, people have tested it and charging speed only starts to degrade after 3-4 rapid charges in one day, with "rapid" in quotes(in tops out at 40kW).
I believe the eGolf which was sold in the US shares the same drivetrain and battery.
Different drivetrain and battery for the eGolf, but both of these are effectively 2013 EVs.
Almost all non-Tesla EVs offer a heat pump option. Most non-Tesla EVs sold do not have one. Just go to your local VW dealer or whatever and see what the specs are on the ID.4's on the lot is.
You can easily read about your example VW MEB platform battery configurations, including built in thermal management system, online at the Munro teardown, for example.
Perhaps you are changing the topic from your original thermal management to heat pump systems specifically?
Those are different goal posts. There are other ways of heating a battery.
Heating, in its various forms, has one big drawback that having a battery that can charge faster in low temps would be really nice in: Starting the day needing to charge.
Ideally, you don't do that, but when traveling sometimes you have to stay at a place that doesn't have a charger, and it's really cold, and now rather than a 30 minute charge it's more like 90 minutes.
You don't even need a heat pump. You can just slightly overvolt the charger, so that some electrical energy is lost as heat rather get than transformed into chemical bonds.
> This is one of those Great New Technology items that smells like a failure simply because it's not competing with the thing the designers think it is.
This technology makes no sense for fast DC charging because there's enough waste heat to keep up the battery temperature, and you can just use some of the power to heat up the battery.
But it can help for slow overnight charging. Keeping battery heated all night is wasteful, but you still want to be able to charge.
That doesn’t work when the problem is the battery is already sub-zero - lithium plating occurs when trying to charge in those conditions, destroying the battery.
You can’t just overvolt out of that - you need an external source of heat until you’re out of the dangerous thermal area.
I'm not sure if that affects all chemistries and compositions. If you look at the spec-sheet for e.g. the LG E63 cells used in some older EVs (notably without TMS), those specify charging down to -20 °C - and the owner's manuals certainly have no warnings in them that the car will implode if you charge in the winter.
Which is really weird. Near as I can tell, it’s just a pouch lipo.
The charge currents for sub-zero are near zero amps, but are still > 0. It should destroy the cell, but apparently doesn’t?
Any insight?
Well it doesn't :D
At least not in a way that people complain about battery failures or degradation. On the other hand, the battery has to reach that temperature in the first place, which may take a couple days of constant exposure to that temperature.
Actually, it does and will in the right conditions. Look at page 11 of that link.
I did some research, and the plating issue happens when charge currents exceed the ability for the battery to absorb them, which dramatically decreases below freezing.
That is why those battery charts show dramatically reduced charge currents (nearly zero) when around freezing.
That data sheet also doesn’t cover cell life in these conditions conditions.
They have very high normal C ratings (hundreds of amps) which is why it is measurable and not actually zero, but reducing it to a couple amps before failure isn’t much different.
If batteries aren’t failing in these conditions, it’s because of some other protective circuit, not because the battery itself is special. It isn’t.
> You don't even need a heat pump. You can just slightly overvolt the charger
The BMW i3 had inductive heating strips underneath the coolant channels in the battery pack[1]. I know our i3 had a heat pump, I presume both were in play.
We used our i3 down to -25C (-13F) many times, didn't have any issues.
[1]: https://youtu.be/JjPIuLz5VFI?t=1124
Heat pumps also serve for more efficient heating when you're driving. Just like at home where a heat pump is more efficient than a resistant heater.
> (and most non-Teslas even today) don't ship with battery thermal management
Some do but don't enable it immediately, but do so with a software upgrade. (such as what happened with Kia EV6/Hyundai Ioniq 5)
I mean this is an incremental improvement that would be very welcome. Why be so negative? Look around the products that have lived through decades of incremental improvements and compare them. Like the phone in your pocket or computer you are using.
Heat pumps struggle to do much at the temperature range the article proposes.
Edit: downvote me all you want, I was responding specifically to “It has to beat a battery with a garden variety heat pump attached” of which EV heat pumps are not garden variety heat pumps, which do struggle at those temperatures. Didn’t think I had to be so pedantic.
Pretty sure the ones in most EVs today work fine at -10C, but they may lose some efficiency. The thing is, there's already mechanisms in some cars to generate waste heat specifically for this purpose. Tesla's already have the ability to run their motors 'inefficiently' generating waste heat, which can be pumped into the battery coolant and heat that. It's no better than electric strip heating, but it doesn't add any cost to the system.
The real benefit, in my view, to being able to charge at cold temps is to improve overall efficiency. If you have to waste some amount of power to heat the battery then that is power that could have been used to charge the car instead...
You bring up a great point. The battery spec is only given at -10C. That's a mild normal day's low temperature in winter in Minneapolis, USA. But it's often much colder than that for long periods of time. I wonder if this glassy layer they apply can handle -30C; a temp where above ground heat pumps are no better than electrical resistive heating.
The 5x delta is stated to be at 14F. That absolutely is within the reasonable operating range of a Model Y heat pump, not sure what you're citing?
It's true that there are very cold environments (Fairbanks winters, say) where in-car thermal management won't be sufficient to keep charging rates high. But those are the same environments where you can't even start a gasoline car without an engine block heater, and I don't see many "no cars in Alaska" arguments on the internet. Everything has limits, but I don't see this battery trickery having much of a home.
You can start gasoline cars just fine down to 20 or 30 below, so long as you keep a good battery in it. Sometimes big diesel trucks use block heaters but gasoline cars don't need them.
I live in a region where -40°C is not unheard of (it happens every winter and stays for up to several weeks). I've also been to another region (not far off) where -50°C is pretty typical.
Gasoline powered engines work just fine in these temperatures, although many cars come with auto ignition systems that start up the engine periodically throughout the night to keep it warm. Otherwise you might have to warm it yourself in the morning using a gasoline powered "torch" (or whatever it's called), which sometimes ends up with the car going up in flames.
So it's honestly pretty funny to read that EV work "down to -10°C". Although probably relatively few of us are desperate enough to be living in such conditions.
Stock gasoline cars do not do well at those temperatures. In Alaska most people with sense use engine block heaters, plugging in every cold night. Besides the issue of having trouble just starting the car, you will put excessive wear and tear on the engine doing it regularly.
And in places like Fairbanks where -40 (F/C) is fairly common in the winter, even cars that merely have an engine block heater will have trouble. You need even more heating pads for the rest of the stuff under the hood of you want to keep a car reliable and healthy in that kind of climate.
Yes, and even then ‘healthy’ is not what people in normal climates think. It puts a lot of wear and tear on vehicles.
They work down to -10. And colder than that too. Apologies to Mitch Hedberg.
Only if they have the ability to stop charging if the battery pack is below freezing, and some way to heat the pack (and keep it) above freezing. Otherwise, charging in those temps will destroy the battery.
I think that's everything but the Nissan Leaf.
Leaf can heat the pack, just no cooling
I've succesfully started my rustbucket diesel from 2009 in -33C. It didn't sound too happy about it, but it did start and run and get to where I wanted
I can definitely say that old/USSR 2.7L gasoline engines for the military came with block heaters. But they were expected to start in -50C / -60F. Good luck getting anything out of an EV at those temperatures.
There's plenty of Norwegians on YouTube testing EVs down to those kinds of temperatures and they work absolutely fine, with the caveat that they won't charge until the battery warms up. Discharging Lithium batteries at really low temperatures isn't an issue, charging them is(because it actively damages them) - but even then the threshold is -32C or around that, easily overcome even with a simple resistive heater.
Norway is not "those kind of temperatures". They get a lot of snow, and maybe -5C and that is all because Gulfstream (the reason Murmansk does not freeze, and it's much farther into Arctic). Otherwise they get it easy.
Now when you move just a bit off the sea, the continental climate kicks in, and you have weeks of -15 -- -20C.
On discharging lithium chemistries at those temperatures or "easily overcame with resistive" let me say that: you just don't know what you are talking about.
The question is, how many people are legitimately living in areas where this is an actual concern in their lives? Outside of Alaska, Canada and Russia barely any place on Earth that relevant amounts of people live in, such low temperatures are a once-in-a-lifetime event.
The question is why you did not do your research before posting this insultingly dismissive missive.
https://ashp.neep.org/ for a list of heat pumps that perform well in cold weather.
it seems a little bit dubious to me. You can't beat the Arrhenius Law, not in Electrochemistry, anyhow. The ion mobility would be very very low, you'd have to rely that the temperature in the battery itself is above 0°C
Nice to see that they require minimal changes at the battery manufacturer. Too often people come up with good ideas like this without accounting for other factors in the supply chain.
can we do it for the smartphones first? without turning them into a furnace
How often are you charging your phone in sub-freezing temperatures?
We already have smartphones charging at 240W: Realme GT3 and Realme GT5.
9.5 minutes from 0 to 100%.
now they just have to figure out how to make it charge while people are lighting them on fire
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