9 ms·

I'm not sure why we aren't making EVs with small but upgradeable batteries. Like for example a $20k car with a 10kWh "good enough for now" starter battery that

by cjdell 4y ago

I'm not sure why we aren't making EVs with small but upgradeable batteries. Like for example a $20k car with a 10kWh "good enough for now" starter battery that can be bought today. Still good enough for 90% of trips and upgradable to 50kWh with additional after market battery modules should the user decide. As simple as upgrading the RAM on an (old) laptop.

noja 4y ago
Like these mopeds with one or two swappable batteries https://electrek.co/2021/11/01/gogoro-electric-scooters-swappable-batteries-continue-rolling-around-the-world/ https://electrek.co/2021/11/01/gogoro-electric-scooters-swap...
iasay 4y ago
I would prefer to see this because the current ability to replace batteries in EVs is crap. I’ve owned enough second hand laptops to know what second hand EV ownership is going to feel like.
- adrianN 4y ago
  Laptop batteries and EV batteries have a completely different performance profile. The data we have suggests that the battery will retain 80% of its maximum capacity for about as long as the rest of the car is expected to survive.
  - ngrilly 4y ago
    Is it mainly because cars are idle/off most of the time, unlike laptops and smartphones, or is there something else at play here?
    - cjdell 4y ago
      Big batteries have much more sophisticated battery management systems that are designed to be as kind as possible to the cells. Also they reserve a capacity of 10% on either side, leaving 80% usable capacity available to the user. Li-Ion batteries don't like being fully charged or fully discharged. Also due to their capacity most EVs are charged at about 0.1C whereas phones (especially with rapid chargers) are charged anywhere between 1C and 3C.
  - iasay 4y ago
    You miss the point. Most people don’t buy new cars. Most people buy second hand vehicles. They now risk degraded batteries and a huge incidental cost. My car cost me £5000 second hand. The cheapest EV battery replacement here is £12,500. I could write that car off twice for the price of a battery and still have enough money to go on holiday. When you buy the bottom end of the second hand EV market which is realistically what most people will have to spend on, you’re looking at the 160 mile range leaf. With an 80% battery that’s 128 miles of range. Which is near useless for the average user. I couldn’t even drive to see my mother in it without charging twice on the way. I will not own an EV as the incidental risk trade off is too high and the up front cost of a new EV is too high.
    - rightbyte 4y ago
      > 128 miles of range. Which is near useless for the average user Maybe if that is your only car. As a commuter or grocery car it would be fine.
      - iasay 4y ago
        Why would you want a car that can be used only for those tasks leaving you to seek other forms of transport for leisure and family? The main positive factor of vehicle ownership is destination and route flexibility and if you trade that away then the advantage is gone.
        rightbyte 4y ago
        The main cost for cheap 2nd hand cars is the fuel in my experience. So you can have a cheap fuel commuter car and a "real" car for trips and towing your boat. Requires parking for two cars though. But since we are talking about an EV it requires a house anyways since most apartments have no charging.
        iasay 4y ago
        Yeah but you can manage the fuel within your cash flow. Difficult to get credit and manage the purchase of a large expensive car. And having two cars is too expensive as well.
  - tzs 4y ago
    > The data we have suggests that the battery will retain 80% of its maximum capacity for about as long as the rest of the car is expected to survive. How long is the rest of the car expected to survive? I rarely do long range driving, and my commute was short for years (a couple miles each way) for about a decade before we switched to work from home a couple years before the pandemic, and I'm not interested in travel so my usage is not going to up much when I retire in a few years. I anticipate a need for at most 100k over the rest of my life, which almost certainly will be less than 25 years. Would a current EV be likely be able to handle that with just reasonable maintenance? I'm currently driving a 2006 Honda CR-V that I bought new and could probably reasonably keep driving another 10-15 years. That's what I want out of an EV.
- bryanlarsen 4y ago
  You're commenting on an article about LFP batteries which have an expected lifespan of about 750,000 kilometers.
  - iasay 4y ago
    When they deliver them and have been on the market for 10 years we have data. Until then it’s vapourware.
    - bryanlarsen 4y ago
      Chinese manufacturers have been shipping LFP car batteries for several years now.
msadowski 4y ago
This idea reminds me of LiGo batteries (https://ebikes.ca/product-info/grin-products/ligo-batteries.html https://ebikes.ca/product-info/grin-products/ligo-batteries....). I think when it comes to the car this idea could be viable but I think the risk is potential change with the weight distribution. You could probably have some weights that are replaced with batteries when you upgrade to keep the weight constant but then you are reducing your range.
tokamak-teapot 4y ago
I’d love a car with a tiny battery for 99% of the time when I’m just driving locally and the ability to have an extra, large battery that can be slotted in when I want to make a longer trip. With only the short range battery most of the time, my car’s weight is low and efficiency high. Maybe I could keep that battery in my house and use it to store solar electricity most of the time. It seems like it should be possible to design a system for slotting it in that doesn’t require me to physically lift its weight. I’d also be happy to drive into somewhere local that rents me that long range battery and slots it in with machinery designed for the purpose.
- alexisread 4y ago
  ...say like a battery trailer with a CCS socket, and with extra storage as well, for long journeys? Low tech FTW. Smartrail is still a better soln but we have to be realistic here.
  - NickNameNick 4y ago
    Will any electric car let you drive while it's plugged in? I'm pretty sure Tesla's Rivians get locked into park when the charger is connected.
    - jsjohnst 4y ago
      > Will any electric car let you drive while it's plugged in? That’s what I was wondering too. Like you, I’m pretty sure the major EVs don’t let you drive while charge, but I haven’t actually tried it.
    - danans 4y ago
      No, even my PHEV doesn't let you drive while plugged in.
    - alexisread 4y ago
      I think you're correct, my Fiat certainly doesn't. That is, however a firmware update away provided the type2 or CCS protocol can distinguish between a mobile or static charger, or be extended to do so. My OP was a slightly off the cuff post to highlight the use of a trailer for say cheap city cars, rather than a removable battery.
clouddrover 4y ago
> I'm not sure why we aren't making EVs with small but upgradeable batteries. NIO is: https://insideevs.com/news/591837/nio-battery-swapping-station-norway-5-minutes/ https://insideevs.com/news/591837/nio-battery-swapping-stati... https://insideevs.com/news/392660/nio-battery-swap-loved-by-customers/ https://insideevs.com/news/392660/nio-battery-swap-loved-by-... https://insideevs.com/news/583809/nio-baas-battery-swapping-opt-out/ https://insideevs.com/news/583809/nio-baas-battery-swapping-... https://insideevs.com/news/596640/nio-500kw-ultra-rapid-chargers-announced/ https://insideevs.com/news/596640/nio-500kw-ultra-rapid-char... > Like for example a $20k car with a 10kWh "good enough for now" starter battery 10 kWh wouldn't get you very far in a car. In a scooter or quadracycle 10 kWh can be useful.
- cjdell 4y ago
  Thanks. > 10 kWh wouldn't get you very far in a car. Tell that to Chevy Volt owners. It's amazing how much all electric driving can be achieved with just a little bit of careful driving. I barely use my range extender now, it's just for the odd long trip.
klondike_ 4y ago
Modern EV design has the batteries integrated into the structural frame of the car. This is because the batteries are the heaviest part of the car, so you want them to be close to the ground and secure from impact. This also makes it very inconvenient to replace. Lots of companies (even Tesla) have attempted the replaceable battery concept but none have been able to make it work efficiently.
- noja 4y ago
  https://www.theengineer.co.uk/content/archive/august-1897-the-london-electrical-cab/ https://www.theengineer.co.uk/content/archive/august-1897-th...
- kryptiskt 4y ago
  NIO is doing battery swapping at scale in China. Here's a random article about how it works: https://insideevs.com/news/591837/nio-battery-swapping-station-norway-5-minutes/ https://insideevs.com/news/591837/nio-battery-swapping-stati...
- cjdell 4y ago
  Would it not be significantly easier if we're using 4 or 5 independent modules instead of a giant monolith? Aren't cars routinely lifted into the air when being serviced? I understand that the structure of the car's body may be suboptimal and require extra reinforcement but if we're really serious about EV adoption and reducing battery cost then perhaps a trade-off worth making?
  - NickNameNick 4y ago
    If you want the batteries to be removable, I suspect the extra couplings in the water coolant loop would make that problematic.
    - silversmith 4y ago
      Check out how tractor hydraulic attachments handle liquid couplings. And hydraulic systems work at much higher pressure than simple coolant loops.
ZephyrOhm 4y ago
Profit motive. Planned obsolescence and the need to buy another within a certain time period.
Gustomaximus 4y ago
Have you seen the video of the bike battery swap. https://youtu.be/yGwmPcClWrE https://youtu.be/yGwmPcClWrE I wonder if a good solution is a smaller fixed battery for lower cost then "range extenders" like this for the bike you can swap in for longer journeys or a topup on a busy day type thing.
jbverschoor 4y ago
Not only that, but the weight of EVs is a huge toll on the infrastructure, esp. in more historic centers
- rcMgD2BwE72F 4y ago
  Compare the weight of a Tesla Model 3 SR (most popular version) and a BMW 3 Series (its most comparable model to the Tesla Model 3). Weight difference is negligible.
  - enragedcacti 4y ago
    BMW sold 50,000 3-series in 2021 whereas Tesla sold 900,000+ Model 3/Ys. Compare the Model 3 to a Camry (300k units), Civic, (260k units), Corolla (250k units), or Accord (200k units), and you'll see the lightest model 3 available weighs more than the heaviest trims of all four, and the 3 is on the lighter side of 250+ mile EVs by a pretty decent margin. Is the BMW causing just as much road damage as a Model 3? yes. Does the weight of the average sedan go up substantially as we convert to EV? Absolutely
verisimi 4y ago
It's almost as if EV is just an excuse to get the consumer to spend waaay more than is needed, wasting all the energy in production in producing cars that cannot be upgraded, than about about minimising the environmental impact. And that's because it is. Corporations do not care about the environment, but they do know a good story when they see it. If they can get you to buy the same car multiple times, this is great business for them. If they can lobby governments to encourage the scrapping of old but serviceable cars, eg by fining non-EVs for their emissions, that means you will be forced to buy sooner. It's all business. Neither corporations nor the governments that service corporations care about either the people or the environment. I wish people would recognise this fact, but corporate-government schooling/science/culture has everyone believing that government is here to help!
bonzini 4y ago
10 kWh is less than 40 miles / 60 km. It's good enough for grocery shopping but it would be akin to always running with your fuel light on and with 1/20th of the fueling stations (ok you would charge at nighttime). I wouldn't be comfortable with that unless I am going to pay for it half of an equivalent ICE car.
- kissiel 4y ago
  I've used a PHEV with 40km of range on electric. It was 100% enough for doing daily driving. I would love to see a small town-oriented not shitboxy EV that's cheaper than fiat500/mini-e.
  - bonzini 4y ago
    Sure, but it's plugin so there's a backup. The parent didn't mention plugin, and a pure electric with a 10 kWh battery might not even be enough to pick up someone at the airport or to visit a friend in the weekend.
- hattmall 4y ago
  That's like 80lbs of LFP batteries, I really don't see why there isn't some easy way to add this to existing ICE cars.
  - bonzini 4y ago
    Retrofitting is a completely different story, I agree.
NullPrefix 4y ago
We already have upgradeable ICE engines. How legal is it to swap a more powerful engine from the same model car? Car companies hate that sort of thing because anything that extends the life of a used car directly translates into a lost new car sale
traviswt 4y ago
Batteries are limited by charge/discharge C rates, which is relative to the size of the pack. Which means not only would your range go down, but so would performance and charge speed. You can push batteries harder, but they’ll generate more heat and degrade faster (lower cycle life). This ends up counterintuitively in a higher long term cost of ownership. Good news is C rates are getting better over time.
ulfw 4y ago
...except that this 'RAM' would weigh hundreds of kilos more and completely and utterly change driving dynamics but yea sure.
mtrimpe 4y ago
I think we should start thinking in battery cargo trailers. When do you want extra range and battery? When you're going on holiday. What do you want apart from extra range when you're going on holiday? Extra storage space! So why not just start selling battery cargo trailers which can provide your main car with extended range when needed? It's also much easier to swap and rent out physically, financially and emotionally than your main car.
- tln 4y ago
  This makes a lot of sense, except that driving with a trailer isn't very enjoyable. I bet the aerodynamics would suffer too
- quesera 4y ago
  Most drivers can't handle trailers. The roads would be so much more dangerous if trailers were commonplace. Trailer hookups can be legitimately difficult. Even in the simplest case, they can be time-consuming. Humans are notoriously bad at backing up with a trailer attached. Heavy trailers (batteries) are extra dangerous -- tail-wagging can be scary! Cars with trailers don't fit in parking spaces. ... A replaceable battery has to be in the underpan of a car. Or split across several battery modules, but keeping the center of gravity low, and between the axles.

by cjdell 4y ago

noja 4y ago

Like these mopeds with one or two swappable batteries https://electrek.co/2021/11/01/gogoro-electric-scooters-swappable-batteries-continue-rolling-around-the-world/ https://electrek.co/2021/11/01/gogoro-electric-scooters-swap...

iasay 4y ago

I would prefer to see this because the current ability to replace batteries in EVs is crap. I’ve owned enough second hand laptops to know what second hand EV ownership is going to feel like.

adrianN 4y ago
Laptop batteries and EV batteries have a completely different performance profile. The data we have suggests that the battery will retain 80% of its maximum capacity for about as long as the rest of the car is expected to survive.
- ngrilly 4y ago
  Is it mainly because cars are idle/off most of the time, unlike laptops and smartphones, or is there something else at play here?
  - cjdell 4y ago
    Big batteries have much more sophisticated battery management systems that are designed to be as kind as possible to the cells. Also they reserve a capacity of 10% on either side, leaving 80% usable capacity available to the user. Li-Ion batteries don't like being fully charged or fully discharged. Also due to their capacity most EVs are charged at about 0.1C whereas phones (especially with rapid chargers) are charged anywhere between 1C and 3C.
- iasay 4y ago
  You miss the point. Most people don’t buy new cars. Most people buy second hand vehicles. They now risk degraded batteries and a huge incidental cost. My car cost me £5000 second hand. The cheapest EV battery replacement here is £12,500. I could write that car off twice for the price of a battery and still have enough money to go on holiday. When you buy the bottom end of the second hand EV market which is realistically what most people will have to spend on, you’re looking at the 160 mile range leaf. With an 80% battery that’s 128 miles of range. Which is near useless for the average user. I couldn’t even drive to see my mother in it without charging twice on the way. I will not own an EV as the incidental risk trade off is too high and the up front cost of a new EV is too high.
  - rightbyte 4y ago
    > 128 miles of range. Which is near useless for the average user Maybe if that is your only car. As a commuter or grocery car it would be fine.
    - iasay 4y ago
      Why would you want a car that can be used only for those tasks leaving you to seek other forms of transport for leisure and family? The main positive factor of vehicle ownership is destination and route flexibility and if you trade that away then the advantage is gone.
      - rightbyte 4y ago
        The main cost for cheap 2nd hand cars is the fuel in my experience. So you can have a cheap fuel commuter car and a "real" car for trips and towing your boat. Requires parking for two cars though. But since we are talking about an EV it requires a house anyways since most apartments have no charging.
        iasay 4y ago
        Yeah but you can manage the fuel within your cash flow. Difficult to get credit and manage the purchase of a large expensive car. And having two cars is too expensive as well.
- tzs 4y ago
  > The data we have suggests that the battery will retain 80% of its maximum capacity for about as long as the rest of the car is expected to survive. How long is the rest of the car expected to survive? I rarely do long range driving, and my commute was short for years (a couple miles each way) for about a decade before we switched to work from home a couple years before the pandemic, and I'm not interested in travel so my usage is not going to up much when I retire in a few years. I anticipate a need for at most 100k over the rest of my life, which almost certainly will be less than 25 years. Would a current EV be likely be able to handle that with just reasonable maintenance? I'm currently driving a 2006 Honda CR-V that I bought new and could probably reasonably keep driving another 10-15 years. That's what I want out of an EV.
bryanlarsen 4y ago
You're commenting on an article about LFP batteries which have an expected lifespan of about 750,000 kilometers.
- iasay 4y ago
  When they deliver them and have been on the market for 10 years we have data. Until then it’s vapourware.
  - bryanlarsen 4y ago
    Chinese manufacturers have been shipping LFP car batteries for several years now.

msadowski 4y ago

This idea reminds me of LiGo batteries (https://ebikes.ca/product-info/grin-products/ligo-batteries.html https://ebikes.ca/product-info/grin-products/ligo-batteries....). I think when it comes to the car this idea could be viable but I think the risk is potential change with the weight distribution. You could probably have some weights that are replaced with batteries when you upgrade to keep the weight constant but then you are reducing your range.

tokamak-teapot 4y ago

I’d love a car with a tiny battery for 99% of the time when I’m just driving locally and the ability to have an extra, large battery that can be slotted in when I want to make a longer trip. With only the short range battery most of the time, my car’s weight is low and efficiency high. Maybe I could keep that battery in my house and use it to store solar electricity most of the time. It seems like it should be possible to design a system for slotting it in that doesn’t require me to physically lift its weight. I’d also be happy to drive into somewhere local that rents me that long range battery and slots it in with machinery designed for the purpose.

alexisread 4y ago
...say like a battery trailer with a CCS socket, and with extra storage as well, for long journeys? Low tech FTW. Smartrail is still a better soln but we have to be realistic here.
- NickNameNick 4y ago
  Will any electric car let you drive while it's plugged in? I'm pretty sure Tesla's Rivians get locked into park when the charger is connected.
  - jsjohnst 4y ago
    > Will any electric car let you drive while it's plugged in? That’s what I was wondering too. Like you, I’m pretty sure the major EVs don’t let you drive while charge, but I haven’t actually tried it.
  - danans 4y ago
    No, even my PHEV doesn't let you drive while plugged in.
  - alexisread 4y ago
    I think you're correct, my Fiat certainly doesn't. That is, however a firmware update away provided the type2 or CCS protocol can distinguish between a mobile or static charger, or be extended to do so. My OP was a slightly off the cuff post to highlight the use of a trailer for say cheap city cars, rather than a removable battery.

clouddrover 4y ago

> I'm not sure why we aren't making EVs with small but upgradeable batteries. NIO is: https://insideevs.com/news/591837/nio-battery-swapping-station-norway-5-minutes/ https://insideevs.com/news/591837/nio-battery-swapping-stati... https://insideevs.com/news/392660/nio-battery-swap-loved-by-customers/ https://insideevs.com/news/392660/nio-battery-swap-loved-by-... https://insideevs.com/news/583809/nio-baas-battery-swapping-opt-out/ https://insideevs.com/news/583809/nio-baas-battery-swapping-... https://insideevs.com/news/596640/nio-500kw-ultra-rapid-chargers-announced/ https://insideevs.com/news/596640/nio-500kw-ultra-rapid-char... > Like for example a $20k car with a 10kWh "good enough for now" starter battery 10 kWh wouldn't get you very far in a car. In a scooter or quadracycle 10 kWh can be useful.

cjdell 4y ago
Thanks. > 10 kWh wouldn't get you very far in a car. Tell that to Chevy Volt owners. It's amazing how much all electric driving can be achieved with just a little bit of careful driving. I barely use my range extender now, it's just for the odd long trip.

klondike_ 4y ago

Modern EV design has the batteries integrated into the structural frame of the car. This is because the batteries are the heaviest part of the car, so you want them to be close to the ground and secure from impact. This also makes it very inconvenient to replace. Lots of companies (even Tesla) have attempted the replaceable battery concept but none have been able to make it work efficiently.

noja 4y ago
https://www.theengineer.co.uk/content/archive/august-1897-the-london-electrical-cab/ https://www.theengineer.co.uk/content/archive/august-1897-th...
kryptiskt 4y ago
NIO is doing battery swapping at scale in China. Here's a random article about how it works: https://insideevs.com/news/591837/nio-battery-swapping-station-norway-5-minutes/ https://insideevs.com/news/591837/nio-battery-swapping-stati...
cjdell 4y ago
Would it not be significantly easier if we're using 4 or 5 independent modules instead of a giant monolith? Aren't cars routinely lifted into the air when being serviced? I understand that the structure of the car's body may be suboptimal and require extra reinforcement but if we're really serious about EV adoption and reducing battery cost then perhaps a trade-off worth making?
- NickNameNick 4y ago
  If you want the batteries to be removable, I suspect the extra couplings in the water coolant loop would make that problematic.
  - silversmith 4y ago
    Check out how tractor hydraulic attachments handle liquid couplings. And hydraulic systems work at much higher pressure than simple coolant loops.

ZephyrOhm 4y ago

Profit motive. Planned obsolescence and the need to buy another within a certain time period.

Gustomaximus 4y ago

Have you seen the video of the bike battery swap. https://youtu.be/yGwmPcClWrE https://youtu.be/yGwmPcClWrE I wonder if a good solution is a smaller fixed battery for lower cost then "range extenders" like this for the bike you can swap in for longer journeys or a topup on a busy day type thing.

jbverschoor 4y ago

Not only that, but the weight of EVs is a huge toll on the infrastructure, esp. in more historic centers

rcMgD2BwE72F 4y ago
Compare the weight of a Tesla Model 3 SR (most popular version) and a BMW 3 Series (its most comparable model to the Tesla Model 3). Weight difference is negligible.
- enragedcacti 4y ago
  BMW sold 50,000 3-series in 2021 whereas Tesla sold 900,000+ Model 3/Ys. Compare the Model 3 to a Camry (300k units), Civic, (260k units), Corolla (250k units), or Accord (200k units), and you'll see the lightest model 3 available weighs more than the heaviest trims of all four, and the 3 is on the lighter side of 250+ mile EVs by a pretty decent margin. Is the BMW causing just as much road damage as a Model 3? yes. Does the weight of the average sedan go up substantially as we convert to EV? Absolutely

verisimi 4y ago

It's almost as if EV is just an excuse to get the consumer to spend waaay more than is needed, wasting all the energy in production in producing cars that cannot be upgraded, than about about minimising the environmental impact. And that's because it is. Corporations do not care about the environment, but they do know a good story when they see it. If they can get you to buy the same car multiple times, this is great business for them. If they can lobby governments to encourage the scrapping of old but serviceable cars, eg by fining non-EVs for their emissions, that means you will be forced to buy sooner. It's all business. Neither corporations nor the governments that service corporations care about either the people or the environment. I wish people would recognise this fact, but corporate-government schooling/science/culture has everyone believing that government is here to help!

bonzini 4y ago

10 kWh is less than 40 miles / 60 km. It's good enough for grocery shopping but it would be akin to always running with your fuel light on and with 1/20th of the fueling stations (ok you would charge at nighttime). I wouldn't be comfortable with that unless I am going to pay for it half of an equivalent ICE car.

kissiel 4y ago
I've used a PHEV with 40km of range on electric. It was 100% enough for doing daily driving. I would love to see a small town-oriented not shitboxy EV that's cheaper than fiat500/mini-e.
- bonzini 4y ago
  Sure, but it's plugin so there's a backup. The parent didn't mention plugin, and a pure electric with a 10 kWh battery might not even be enough to pick up someone at the airport or to visit a friend in the weekend.
hattmall 4y ago
That's like 80lbs of LFP batteries, I really don't see why there isn't some easy way to add this to existing ICE cars.
- bonzini 4y ago
  Retrofitting is a completely different story, I agree.

NullPrefix 4y ago

We already have upgradeable ICE engines. How legal is it to swap a more powerful engine from the same model car? Car companies hate that sort of thing because anything that extends the life of a used car directly translates into a lost new car sale

traviswt 4y ago

Batteries are limited by charge/discharge C rates, which is relative to the size of the pack. Which means not only would your range go down, but so would performance and charge speed. You can push batteries harder, but they’ll generate more heat and degrade faster (lower cycle life). This ends up counterintuitively in a higher long term cost of ownership. Good news is C rates are getting better over time.

ulfw 4y ago

...except that this 'RAM' would weigh hundreds of kilos more and completely and utterly change driving dynamics but yea sure.

mtrimpe 4y ago

I think we should start thinking in battery cargo trailers. When do you want extra range and battery? When you're going on holiday. What do you want apart from extra range when you're going on holiday? Extra storage space! So why not just start selling battery cargo trailers which can provide your main car with extended range when needed? It's also much easier to swap and rent out physically, financially and emotionally than your main car.

tln 4y ago
This makes a lot of sense, except that driving with a trailer isn't very enjoyable. I bet the aerodynamics would suffer too
quesera 4y ago
Most drivers can't handle trailers. The roads would be so much more dangerous if trailers were commonplace. Trailer hookups can be legitimately difficult. Even in the simplest case, they can be time-consuming. Humans are notoriously bad at backing up with a trailer attached. Heavy trailers (batteries) are extra dangerous -- tail-wagging can be scary! Cars with trailers don't fit in parking spaces. ... A replaceable battery has to be in the underpan of a car. Or split across several battery modules, but keeping the center of gravity low, and between the axles.