Re:Electric vehicle battery capable of 98% charge in less th...
by Xylakant on Tuesday June 14, 2022 @02:34AM
(#31735435)
You math it a little confusing when it come to the cooling required. You scale up the power draw to an hour, but then take your cooling based on that. But each individual battery still only needs to dissipate the heat produced during its charge - so in your example, with 60kWh and 99% efficiency, the energy to dissipate is 0.6kWh per charge, over the duration of 5 minutes. Which sounds much more manageable than the 7.2kWh you end up with (which would be for 12 charges over the course of an hour).
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Re:Electric vehicle battery capable of 98% charge in less th...
by CodeShmode on Tuesday June 14, 2022 @02:58AM
(#31735599)
He scales the kW/h hour down to five minutes to make kW/5min.
Re:Electric vehicle battery capable of 98% charge in less th...
by proto_lambda on Tuesday June 14, 2022 @04:28AM
(#31736177)
0.6kWh / 5min * 60min/1h is still 7.2kW. It only needs to handle those 7.2kW of heat loss for five minutes, not continuously, but the power doesn't change.
Re:Electric vehicle battery capable of 98% charge in less th...
by Xylakant on Tuesday June 14, 2022 @04:35AM
(#31736211)
The power doesn’t change, but you get 12 systems that each need to dissipate 600Wh instead of a single system that needs to dissipate 7200Wh. You can for example partially buffer the heat if you know that you only need to handle that load for a few minutes. It’s much harder to sustain the same energy dissipation for an hour.