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Comment by zamfi | Hacker News Reader

> low temperature performance

Doesn't that make li-ion unsuitable for, e.g., ICE vehicles that need to start at low temperatures?

The batteries in EVs are definitely not as "forget about it" as the lead acid's in gas cars!

In some ways they are more "forget about it" than lead acid -- lithium battery life is measured in cycles, rather than time. Your lead acid battery will be dead in 5 years, but your lithium batteries can last for 5,000+ cycles, even more if the cells are intelligently discharged.

As for cold temperatures -- less current can be drawn from each cell. In those cases, you can add more cells to still perform adequately in the cold. And this may even fit in the same form factor as the existing lead acid battery, because lithium batteries are physically smaller.

An li ion battery of the same capacity will supply less cranking current, but you can make it slightly larger (still much lighter and smaller than SLA) and make up for that difference. It's only below -30 Celsius (-20 to -40 depending on the chemistry) that lead acid retains better capacity, and they freeze completely at -80.

Li-ion will last far, far longer than any lead acid under any conditions.

Yeah I have an EV that gets 240 miles on a warm summers day but it drops down to like 160 on a day where it’s below freezing climbing a mountain. I’m OK with that. It’s still an absurd amount of range for a technology that would have been unthinkable a decade or two ago. I think once EVs start surpassing ICE cars in range it will be a non issue for most people.

A 33% drop in efficiency sounds reasonable for climbing a mountain vs driving on flat land. Do you know how much your range drops when you're driving in the cold but not climbing a mountain?

Some EVs just heat their battery, which limits the loss of range. The power for heating can be automatically drawn from the charging station in the early morning. Some EVs also start heating the cabin when you schedule it and they are plugged in (eg Ioniq). EVs can also start and go without any problems in conditions where gas cars give up (-20 celcius).

Mine drops that much when below freezing on a FLAT surface. On one hand, it's better than prior systems. On the other hand, it's still abysmally worse than conventional systems.

This is just one of the many risks of being an early adopter, I suppose.

I agree that once this major bottleneck is removed, the vehicle will be much more competitive - assuming the fix doesn't increase the cost too much.

Lots of motorcyclists replace their lead-acid batteries with lithium-ion batteries that are much lighter. They’re very unreliable but some people will deal with that to save a few pounds.

I imagine you mean ice cars with much more demanding starters, but worldwide motorcycle market is pretty big.

You still get about half range in -20C with cabin heating.

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