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Right now AFAIK batteries are placed deep in the guts of the car, cf the "electric skateboard" design. This is because they are large and heavy so you have to spread the weight around.

Thus hard to replace.



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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.


The bigger problem is batteries have moved into "structural elements" in the current "skateboard" designs. Removing the batteries potentially damages the foundational structure of the car and may need expensive mitigations.

I think you are missing something: where do you put the replaceable batteries?

Tesla's battery packs are distributed throughout the car, both to allow for cargo space (not having a trunk would be something of a minus) and to distribute the weight of all those batteries. I am having a very hard time envisioning a way to achieve both of those goals while making the batteries replaceable.


The batteries in this car are not easily replaceable I believe. This is one of the problems of this solution - coming up with a size and spec standard.

One of the main reasons why we consider electric vehicles to be so cool is their low center of gravity, thanks to the batteries being located near the very bottom (good to have them there, and also batteries are better not to be damaged in a crash). Can we find such a place in existing cars? Maybe we can use space under seats and in place of the fuel tank and the spare tire. But in this case batteries need to come in small modules.

And the majority of cars have batteries as part of the chassis. Swapping it is nearly impossible.

The batteries are located under the car, and their base plate is more armored than your usual car undercarriage.

edit: floor, floor -> base plate, undercarriage. Thanks grinich for improving my vocabulary.


How about switching out those batteries

Batteries in most electric cars are squeezed in every possible location. It's not just a cube you can slide out the side of the car.

If it was a cube, you'd either have to make the car really big or cut the range in half.

Maybe they've found some way around it with the Tesla, but it isn't usually just that they don't like the idea of battery-swap stations.


One of the issues is the battery is the heaviest part of the car, and tend to be pretty large. Most EVs today are basically built around the battery, using it as a foundation that everything else attaches to.

Making it replaceable means sacrificing range, because the battery must be smaller and there's more weight for a frame to hold the battery pack(s).

This is in addition to the more practical problems such as standardizing packs, network of swap stations, ownership of the batteries. If the packs are big you need a machine at every station (which can break), but if they're small enough for a driver to swap you sacrifice even more range and increase other potential problems like theft.


That's a brilliant solution to the problem for cars that aren't Teslas, which has something like 1800 batteries lining its cabin floor. I don't think they'd be easily swapped.

For cars that don't implement batteries this way, I'm wondering how they allow for non-floor-mounted installations preventing the batteries from destroying their handling.

Further, how are the filling stations expected to deal with the variety of non-standard battery types on the market?


It's interesting that Porsche put the battery under the driver's seat (in the cabin? unclear). Wonder if that made it more dangerous. Are modern EV batteries also in the passenger area or in their own little armored section...?

They're not meant to be replaced by hand - it's an automated process that swaps the batteries after you pull the car into the proper position, sort of like pulling into a car wash.

Electric car batteries are large. It is hard to remove them without also taking apart a big part of the car at the same time

The thing you are missing is that currently, batteries are built in to the structure of the vehicle. To do otherwise would necessarily reduce the size of the battery significantly, as now the battery needs to fit in a convenient to remove location, and all the parts necessary to enable insertion/removal of the battery would take up space. Not to mention that the batteries are wickedly heavy, too heavy to be lifted by a single person, so there would need to be a machine to swap them, which takes up real estate at the gas station, and just generally complicates things.

Maybe there will be swappable batteries eventually, or one part of the battery will be swappable, but as far as I understand thats not coming soon.


Aren't batteries under the cabin floor though? That hot-swap demo from few months ago seemed to imply that they were.

Batteries are the heaviest part of an EV, and it is super easy and...actually obvious, just to distribute them evenly under the vehicle.

Do you have any examples of designs where batteries are literally integrated into vehicle structure?

The iconic Tesla battery-skate design is still modular/replaceable for example (they're all 18650/2170/etc cells).


Why do you say the batteries cannot be replaced? Swapping a battery literally takes five minutes. The cost of a new one is high, but will likely come down.

As for why these cars exist, it's simple: they're awesome cars. They're powerful and quiet and have advanced technology. Never mind environmental concerns, not having to visit the gas station is just very convenient.

Not emitting (local) pollution is a nice bonus, but it's pretty far down the list.


Having the chassis of the car be the battery seems problematic. Once the battery is worn out the whole car must be disposed of.
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