DaveinOlyWA wrote:missed my point. charging usually does not generate as much heat as discharging. u will most likely charge in garage, out of sun, etc. batteries will be relatively cool especially if doing timer charge for better TOU rates.
one question that i am not sure of; for quick charging must generate some sort of heating issue. since mostly likely batteries would have been recently discharged so would be warmer than normal. wondering if time to 80% might be significantly longer in summer than winter especially in AZ?
I would expect the pack would be warmer during the later stages of a quick charge, but since the quick charge is only to 80%, we stay away from the last 20% when most of the charging heat is generated.
I'd expect the motor and controller to generate more heat than the battery at high speeds and/or hill climbing. (But with water cooling this will be a non-issue.)
I'm still working on my battery guessing, but it's looking more like the pack of 48 four-cell modules is two strings of 24 for about 345V nominal. If the Leaf cells are the 33Ah capacity listed on AESC's site, and if they're capable of a 10C discharge rate,**
then each string should be good for 330A continuous and two parallel strings should be good for 660A. I'm thinking the pack is going to be absolutely loafing during all phases of operation - and I really don't expect heat during charge or discharge to be a problem (or a factor). I'd be surprised if the Leaf draws more than 250A max.
A 10C discharge rate is pretty low to average for current cells. These old 20Ah LiMn cells from EiG
are 5C continuous, 10C peak. Even if the Leaf pack was made from 5C capable cells, that's 330A continuous for two parallel strings, and 660A for <10 second pulses.