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Comment by IneffablePigeon | Hacker News Reader

One could say the same about a combustion engine, really. Battery packs last way, way longer than most people think because they analogise it to phone batteries which are quite different. The resale value of a degraded pack is also going to be higher than most people assume, I think. Unfortunately we have not had plentiful EVs with good battery packs for long enough to show this to the average consumer.

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I guess the question comes down to how does one know if the battery pack is good? When I buy a regular used gas car, I can get all sorts of diagnostics about it out of the OBD2 port, pull a spark plug and stick a scope into the combustion chamber to see if there's any issues (e.g. on the walls).

With an electric car, how can one tell if the pack has been charged all the way up to 100% all the time (vs. the much better 40-70% range)?

This is the "term premium" of batteries it seems, and I honestly don't know if there's a reliable answer.

At least on our PHEV, when you read out the battery module state with an OBDII reader, you get to know not only the current estimated capacity but also how much time it's spent at various states of charge, how much time it's spent being charged and discharged at different currents, how much time it's spent at different temperatures, and a completely absurd amount of other diagnostics.

I'd feel a lot better about the state of the battery if I bought one used, rather than the state of the ICE. It's possible to borescope it, but you have no way of telling how long the previous owner went between oil changes, if they flogged it out to redline regularly, etc.

With my electric car, I can plug into the ODB port and get highly detailed information on the health of the battery. Far deeper insights than what I get plugging into an ODB port on an ICE.

Getting into the technician menus on Teslas is well documented, they also report a ton of data and can do a lot of diagnostics on the battery.

you just need to know the SoH (state of health). If that's 90% then you've lost 10% of the range at new. The lower the SoH for the same vehicle make, model, year and driven kms, then the worse the car has been treated. Simple as that.

I'm reminded of various videos on Youtube where they dissect grenaded engines. "Oh look, the Cummins in your pickup dropped a valve seat. That's going to cost you $50K."

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