[HN Gopher] Charging electric vehicles 5x faster in subfreezing ...
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       Charging electric vehicles 5x faster in subfreezing temps
        
       Author : gnabgib
       Score  : 145 points
       Date   : 2025-04-05 00:38 UTC (2 days ago)
        
 (HTM) web link (news.umich.edu)
 (TXT) w3m dump (news.umich.edu)
        
       | ajross wrote:
       | 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.
        
         | givinguflac wrote:
         | 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.
        
           | Kirby64 wrote:
           | 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...
        
             | superkuh wrote:
             | 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.
        
           | ajross wrote:
           | 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.
        
             | idiotsecant wrote:
             | 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.
        
               | lstodd wrote:
               | 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.
        
               | gambiting wrote:
               | 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.
        
               | mschuster91 wrote:
               | 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.
        
               | homebrewer wrote:
               | I live in a region where -40degC 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
               | -50degC 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 -10degC". Although probably relatively few of us are
               | desperate enough to be living in such conditions.
        
               | recursive wrote:
               | They work down to -10. And colder than that too.
               | Apologies to Mitch Hedberg.
        
               | lazide wrote:
               | 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.
        
               | recursive wrote:
               | I think that's everything but the Nissan Leaf.
        
               | idiotsecant wrote:
               | Leaf can heat the pack, just no cooling
        
               | lupusreal wrote:
               | 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.
        
               | lazide wrote:
               | Yes, and even then 'healthy' is not what people in normal
               | climates think. It puts a lot of wear and tear on
               | vehicles.
        
               | crummyglow wrote:
               | 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
        
           | Rygian wrote:
           | https://ashp.neep.org/ for a list of heat pumps that perform
           | well in cold weather.
        
         | cyberax wrote:
         | 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.
        
           | magicalhippo wrote:
           | > 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
        
           | OptionOfT wrote:
           | 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.
        
           | lazide wrote:
           | 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.
        
             | formerly_proven wrote:
             | 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 degC - and the owner's
             | manuals certainly have no warnings in them that the car
             | will implode if you charge in the winter.
        
               | lazide wrote:
               | 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?
        
               | formerly_proven wrote:
               | 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.
        
               | lazide wrote:
               | 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.
        
         | jjtheblunt wrote:
         | > 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?
        
           | ajross wrote:
           | 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.
        
             | jjtheblunt wrote:
             | 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?
        
             | recursive wrote:
             | Those are different goal posts. There are other ways of
             | heating a battery.
        
           | gambiting wrote:
           | 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.
        
             | formerly_proven wrote:
             | Different drivetrain and battery for the eGolf, but both of
             | these are effectively 2013 EVs.
        
         | linsomniac wrote:
         | 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.
        
         | jbm wrote:
         | 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.
        
           | ajross wrote:
           | > 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.
        
             | gopalv wrote:
             | > 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.
        
               | justinrubek wrote:
               | 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.
        
               | Ajedi32 wrote:
               | ???
               | 
               | 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.
        
               | rconti wrote:
               | There are entire nations where this is the scenario all
               | winter.
        
               | vitaflo wrote:
               | 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.
        
               | detaro wrote:
               | that, or you have some broken thing connected that draws
               | way to high idle current.
        
           | sbierwagen wrote:
           | 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.
        
         | bdcravens wrote:
         | > (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)
        
         | jve wrote:
         | 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.
        
       | hinkley wrote:
       | 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?
        
         | homeless_engi wrote:
         | 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
        
           | gmac wrote:
           | Not only Teslas: my Renault has this as standard, and many
           | brands have it at least as an option.
        
         | edaemon wrote:
         | 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.
        
           | xattt wrote:
           | 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.
        
             | ssl-3 wrote:
             | 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.
        
               | close04 wrote:
               | > 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.
        
               | subscribed wrote:
               | 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.
        
               | xattt wrote:
               | The general population is now more tech literate than a
               | couple of decades ago. They'll be fine.
        
               | LoganDark wrote:
               | > 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.
        
               | Clent wrote:
               | People who experience range anxiety have an internalized
               | incentive to seek out these options.
        
             | tirant wrote:
             | 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.
        
             | officeplant wrote:
             | 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.
        
           | jillesvangurp wrote:
           | 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.
        
             | hinkley wrote:
             | 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?
        
               | officeplant wrote:
               | >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-...
        
         | ethagknight wrote:
         | 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.
        
         | Rebelgecko wrote:
         | 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
        
         | eatporktoo wrote:
         | 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...
        
       | ellisv wrote:
       | Link to the research article:
       | https://www.cell.com/joule/abstract/S2542-4351(25)00062-5
        
       | Animats wrote:
       | 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/
        
         | cuu508 wrote:
         | > 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.
        
           | nicolaslem wrote:
           | Most consumer LiFePO4 power stations have this sensor and cut
           | charging below 0C, still allowing discharge up to around
           | -10C.
        
             | LinuxBender wrote:
             | 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.
        
               | cuu508 wrote:
               | 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?
        
               | lazide wrote:
               | Just look for 'self heating'
        
               | cuu508 wrote:
               | 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?
        
               | lazide wrote:
               | Self heating lithium iron phosphate battery [https://batt
               | lebornbatteries.com/shop/products/batteries/heat...]
        
               | cuu508 wrote:
               | 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 0degC thing.
        
               | wongarsu wrote:
               | 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.
        
               | LinuxBender wrote:
               | 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
        
           | hgomersall wrote:
           | 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...
        
         | malchow wrote:
         | 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/
        
       | throwaway41029 wrote:
       | 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
        
         | indemnity wrote:
         | 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?
        
           | ffsm8 wrote:
           | 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
        
             | LoganDark wrote:
             | 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.
        
               | mschuster91 wrote:
               | > 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.
        
               | LoganDark wrote:
               | 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?
        
               | FirmwareBurner wrote:
               | _> 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.
        
               | hulitu wrote:
               | > 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.
        
               | LoganDark wrote:
               | > 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.
        
               | mschuster91 wrote:
               | > 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.
        
               | fransworst wrote:
               | China has lower levels of extreme poverty than the US: ht
               | tps://en.wikipedia.org/wiki/List_of_countries_by_percenta
               | g... (percentage living off of less than 2.65USD a day).
               | 
               | They also have lower per capita emissions than the US: ht
               | tps://en.wikipedia.org/wiki/List_of_countries_by_carbon_d
               | i...
        
               | StopDisinfo910 wrote:
               | > 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.
        
               | FirmwareBurner wrote:
               | _> 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.
        
               | bojan wrote:
               | Nothing unfair about it, it is easy to build a car for
               | cheaper if you don't care about worker rights and the
               | environment.
        
               | LoganDark wrote:
               | 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.
        
               | officeplant wrote:
               | 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.
        
               | xeromal wrote:
               | 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.
        
           | bgnn wrote:
           | 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.
        
             | 3D30497420 wrote:
             | > 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.
        
               | InDubioProRubio wrote:
               | 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.
        
               | tonfa wrote:
               | > 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.
        
           | Peanuts99 wrote:
           | Isn't their plan to sell them to charger operators?
        
             | notahacker wrote:
             | 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.
        
         | timerol wrote:
         | 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.
        
         | bufferoverflow wrote:
         | That requires 1 megawatt chargers. For each charger.
         | 
         | Not saying it's impossible, but that won't be easy.
        
           | michaelt wrote:
           | 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.
        
       | saurabhshahh wrote:
       | can we do it for the smartphones first? without turning them into
       | a furnace
        
         | awiesenhofer wrote:
         | How often are you charging your phone in sub-freezing
         | temperatures?
        
         | bufferoverflow wrote:
         | We already have smartphones charging at 240W: Realme GT3 and
         | Realme GT5.
         | 
         | 9.5 minutes from 0 to 100%.
        
       | wolfi1 wrote:
       | 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 0degC
        
       | byyoung3 wrote:
       | now they just have to figure out how to make it charge while
       | people are lighting them on fire
        
       | RKFADU_UOFCCLEL wrote:
       | 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.
        
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