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Comment by r00fus | Hacker News Reader

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r00fus·

Explain my 7.5 year old EV with 95% battery health and 65k miles driven?

Your 2nd sentence has issues with reality.

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Some EVs start with capacity “gated off” to limit the depth of early cycles and provide a more graceful degradation.

But a lifetime of 3y doesn't jive with why my 7 year old vehicle is mostly fully functional. Even with 10% over-provisioning (amazingly expensive 7y ago), that's only a 15% reduction in 7 years.

The statement "The life of the commonly used chemistries is only around 3 years" is completely misleading and probably inaccurate.

I don't know about the 3 years number, but generally speaking battery lives are estimates/averages based on statistics. If you have a battery that was well cared for it will outperform the average. Also sometimes it's just dumb luck. One aberration isn't nearly enough data to throw out the entire premise

It depends on your usage too, along with the exact chemistry and form factor of the lithium battery.

A lot of people report lithium batteries swelling up in their phones/tablets around 3-4 years of usage.

Phone batteries are lithium polymer pouch cells, the least durable type commonly used. Car cells with lithium ion NMC cylindrical cells are much better, and LIFEPO4 in turn is several times more durable than that.

You would be wise to insist on an EV with LIFEPO4 batteries in the sense that calendar lifetimes are more likely to be on par with traditional engines.

The explanation is simple. OP said commonly used chemistries. That would be something like LCO. Your EV battery is probably NMC.

NMC is the most commonly used battery chemistry in the US for EVs which is what this thread was all about.

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