alt Hacker NewsDoes anyone know if they have looked at how charging quickly impacts the longevity of the battery? Can the cells be damaged by the rapid increase in temperature and current?
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Significant work has been done on the "dendritic" failure mode of electrodes, where crystals grow from one electrode to another and may punch through separator membranes. This has gradually increased cell lifetimes. Now it's all down to temperature. Control-loop monitoring has got a lot better than "shove X amps in there and hope for the best".
There's been a lot of study into this already and the forming consensus is that fast DC charging is less of an issue on battery longevity than was first thought. In cars with decent thermal management systems it seems to have a fairly limited effect on battery lifetime as opposed to natural calendar aging.
Fast charging appears to damage batteries less than expected. There are lots of reports of taxis which almost exclusively used fast charging with over 200,000 miles on their battery.
Of course that is normal fast charging. Flash charging is 3x or more faster, so that's unknown.
Overall it's less the lone act of moving ions and more the heat that affects battery longevity.
BYD is using, among other methods, a "3D direct refrigerant cooling system", so the batteries are dipped in phase-changing coolant.
Aside from that the cells are pre-warmed and were optimised for lower internal resistance.
Probably a bit but here’s the thing: if charging fast is, well….faster…then people care less if they loose a little extra battery because getting it back is less inconvenient.
There’s a graph i imagine here where slow charging, you want to retain all capacity. Faster it gets, you tolerate more battery loss.
I looked, but didn't find anything. Perhaps it's too early to tell?
Even if it did, this type of rapid charging only happens on long road trips.
I don’t specifically know for this type of battery but I’ve looked at pretty in-depth analysis of smartphone batteries (way less sophisticated battery management tech) and fast versus slow charging made very little lifespan difference. The best mitigations were fewer cycles and keeping the battery in its sweet spot (not discharging to 0% and charging to 100%)