Lithium batteries on cars/boats

[Kelpie]

Yep. But there are vastly different ways of doing it. The existing ways are crude. Full immersion cooling isnt happening yet

In my extremely limited experience, it's the BMS which gets hot, not the cells.
Is this different for EVs?

 

[Chiara’s slave]

Yep. But there are vastly different ways of doing it. The existing ways are crude. Full immersion cooling isnt happening yet

It’scalso a trick answer, cos up until very very recently they have all been NiMH, not lithium based batteries. Which is why they’re liquid cooled even though they are pathetically small. The China syndrome is always just a heartbeat away with NiMH.

 

[Chiara’s slave]

In my extremely limited experience, it's the BMS which gets hot, not the cells.
Is this different for EVs?

In a normal situation you’re right. Various extreme circumstances, including a BMS failure, can lead to over warm batteries. The now common huge charge/discharge rates aren’t usually the culprits.

 

[Refueler]

As new cheaper cars come available the price of secondhand will drop a lot. The cheapest cars to run currently are LPG not electric. Not suggesting he buys new. Just holds fire until the Chinese cars hit the forecourts at half the price of current big car manufacturers. They will all need to drop their prices so second hand will also drop substantially

LPG is not cheapest round here .... its had a multiple increase same as electricity due to the sanctions against Russian supply. Now we have a mix of North Sea with USA gas ... Quality of gas has suffered using USA product.

For years - my Lab was the only Lab in the Baltics to test LPG ...... I sold it to a competitor who now conducts most of the testing.

 

[Refueler]

Tesla’s big breakthrough is the battery management....cooling and sophisticated software

Mate of mine bought a TESLA ..... he was all cock-a-hoop with it ... telling everyone he had it ..... 3 months later he is trying to sell it ... and no takers.

I had a shufty at it and was not impressed by it ... build quality ??

As regards Battery setup in TESLA ... I know they are perhaps more on road than any other model - but they do seem to be the ones that catch fire ... rare I agree ... but still top of the table

 

[Bouba]

Mate of mine bought a TESLA ..... he was all cock-a-hoop with it ... telling everyone he had it ..... 3 months later he is trying to sell it ... and no takers.

I had a shufty at it and was not impressed by it ... build quality ??

As regards Battery setup in TESLA ... I know they are perhaps more on road than any other model - but they do seem to be the ones that catch fire ... rare I agree ... but still top of the table

Yes....the Tesla sales figures and survival rates match exactly what your mate says....

 

[geem]

In my extremely limited experience, it's the BMS which gets hot, not the cells.
Is this different for EVs?

In extreme charge/discharge situations cells get hot. The current move with EV development is to vastly shorten charge times. This means a lot of amps going in to the battery very quickly. Cells get hot without very effective cooling. Cold plates under the batteries as Tesla do isn't going to hack it. It need a step change in how this can be achieved.
A small Nissan Leaf specialist in New Zeland is actually ahead of the curve. Proper immersion cooled cells offering a vastly superior battery than the one Nissan built. He is a tiny business without the massive investment that the big car makers can bring to the table. EV batteries will soon be quite different

 

[Refueler]

In extreme charge/discharge situations cells get hot. The current move with EV development is to vastly shorten charge times. This means a lot of amps going in to the battery very quickly. Cells get hot without very effective cooling. Cold plates under the batteries as Tesla do isn't going to hack it. It need a step change in how this can be achieved.
A small Nissan Leaf specialist in New Zeland is actually ahead of the curve. Proper immersion cooled cells offering a vastly superior battery than the one Nissan built. He is a tiny business without the massive investment that the big car makers can bring to the table. EV batteries will soon be quite different

Its not only cooling ... the physical change the cells have to endure is still a limiting factor. Even though you can cool the battery - the cells are still being damaged by too high charge rates.

Its no different to old days of NiCd's in model cars where we were thumping in charge and a fan sitting over the battery to try control its temp. Lithium may be a better battery - but it still suffers the same.