Filip K
Member
They're probably very concerned about lithium plating with this new cell so they're not taking any chances. It's quite irreversible, so why risk it right now, when they're just trying to fully validate a pack from a new vendor?
It could also just be a software bug, if lithium plating is not a concern at 15-16C, where it started, before engaging the heater. I thought that for relatively low charge rates it really should not be a problem until close to 0C. You can see the BMS Max Charge value (looks like the maximum amount of charge power the battery can accept) far exceeds the available power at all times, so it seems like it really shouldn't need to warm the battery.
Interesting data though. Interesting how cell voltage doesn't get all the way to 4.2V. But there's no data on that value when nothing is running (heater was running pretty hard) so hard to say what the open-circuit voltage would be. Maybe it's actually 4.2V.
Definitely, there is a deadline to a max charge / regen power 0 kW when the pack temp is under 0 °C. No regen (0 kW) today at 60 % SoC and 0 °C. You are right, it should be OK if a new pack is heated to 20 °C due to lithium plating. But why 40 °C with 0.15C? The car is now sleeping at 99 % SoC and I will see the values after a couple of hours when the BMS will be done.
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