Comment by hackingonempty
2 days ago
Don't forget calendar life. Lithium batteries degrade over time even if you do not cycle them. The life of the commonly used chemistries is only around 3 years.
2 days ago
Don't forget calendar life. Lithium batteries degrade over time even if you do not cycle them. The life of the commonly used chemistries is only around 3 years.
Explain my 7.5 year old EV with 95% battery health and 65k miles driven?
Your 2nd sentence has issues with reality.
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.
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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.
Degrade to what extent? I have a 12 year old Nissan Leaf that's lost maybe 25% of its range. Still absolutely usable as a neighborhood car.
A 2013 Nissan Leaf should get 60-75 miles of range (depending on how much of thebattery you use, as well as climate, and other driving conditions). If it got ~80 miles new, it would still get 60 miles now. That might be enough for someone to make a short commute, though unless they have relatively fast charging at home, a 20+ mile commute 5 days a week might be tough to pull off. But most errands would fall well within the existing / remaining range.
50 mile round trip at 3 miles per kWh would be under 20kWh, or 1.6kW for 12 hours, about the same as a plug in heater on max, easily doable in a normal socket let alone a dedicated charge circuit.
I think most testing uses 80% capacity as the cutoff point. Largely because that's when the loss in capacity really slows down.
> neighborhood car
Not familiar with that term, what does it mean? Shared ride? A car for walking distances?
I think they mean "city car" as opposed to "road trip car" or "rural car."
Going to work, groceries and so on, the regular stuff.
If the city was walkable, you would not need such a thing as neighborhood car, you could just use a bike, but apparently as a society at many places we have decided that the cars are the best mode of transportation ever.
An electric wheelchair.
If it has moved like 250K km then it is impressive.