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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 ch

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 2y ago
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 https://www.youtube.com/watch?v=DyGgrkeds5U
- gmac 2y ago
  Not only Teslas: my Renault has this as standard, and many brands have it at least as an option.
edaemon 2y ago
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 2y ago
  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 2y ago
    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 2y ago
      > 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 2y ago
        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 2y ago
        The general population is now more tech literate than a couple of decades ago. They’ll be fine.
      - ssl-3 2y ago
        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.
        close04 2y ago
  - tirant 2y ago
    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 2y ago
    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 2y ago
  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 2y ago
    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 2y ago
      >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-number/l1mh18e254bc/part/hv-coolant-heater/partid/21030176/ https://www.proxyparts.com/car-parts-stock/information/part-...
ethagknight 2y ago
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 2y ago
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 2y ago
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-battery-pack-architecture/ https://electrek.co/2017/08/24/tesla-model-3-exclusive-batte...

homeless_engi 2y ago

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 https://www.youtube.com/watch?v=DyGgrkeds5U

gmac 2y ago
Not only Teslas: my Renault has this as standard, and many brands have it at least as an option.

edaemon 2y ago

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 2y ago
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 2y ago
  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 2y ago
    > 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 2y ago
      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 2y ago
        The general population is now more tech literate than a couple of decades ago. They’ll be fine.
    - ssl-3 2y ago
      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.
      - close04 2y ago
- tirant 2y ago
  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 2y ago
  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 2y ago
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 2y ago
  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 2y ago
    >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-number/l1mh18e254bc/part/hv-coolant-heater/partid/21030176/ https://www.proxyparts.com/car-parts-stock/information/part-...

ethagknight 2y ago

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 2y ago

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 2y ago

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-battery-pack-architecture/ https://electrek.co/2017/08/24/tesla-model-3-exclusive-batte...