Many recent posts about installing the fastest charger and why this might not be the best approach?

dtbaker61

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Because summers in Arizona (Phoenix) are HOT. So I would want to wait until it's below a 100°.
I'm pretty sure the battery packs have enviro cooling internally.... AND they are fine anywhere below 120 deg F. Unless you've seen some warnings for charging at temps over 100 deg f? Most chargers I know of have temp sensors in the battery case, and will reduce current if temps are too high.
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Rhynri

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I don't know the exact internals of the Tesla BMS/control system, but would guess that the current draw is limited on cold batteries for two reasons. One is cold Li voltage 'sags' a little under heavy loads, which means even MORE current is required for the same kW output. Most likely is is current limiting kicking in rather than simply because of temperature.
Makes sense to me.

This is why if you want maximum output from a cold pack... it's actually GOOD to do a couple 'acceleration events' under moderate/heavy load to warm up the cells.
I might drive boring once I hit the speed limit, but until then, all my driving is 'acceleration events', thank you very much. :p

Thanks again for the explanations. Makes me wonder why the Sparks have such bad battery degradation. But then again, they are tiny (<20kWh, i forget exact...) and allow for 120kW discharge and 60kW regen. And 50kW DCFC if equipped.
 

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That's interesting, I didn't know that. Thanks! Since Tesla limits the amount of acceleration on a cold battery, I assumed it was for battery longevity.

Edit: Clarity
Aren't they limiting regen on cold batteries?
 

shutterbug

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I'm pretty sure the battery packs have enviro cooling internally.... AND they are fine anywhere below 120 deg F. Unless you've seen some warnings for charging at temps over 100 deg f? Most chargers I know of have temp sensors in the battery case, and will reduce current if temps are too high.
You're right. In fact the operating temperature range for most chargers that I've seen is -22º to
+122º. While the temperature rarely gets to 122º, my garage is frequently 15º to 20º hotter than the outside temperature. So, since I am getting a fast 48A charger, why not wait for a few hours when things cool down a bit.
 

Carlsbad9

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I think we all agree that slower charge rates are better than higher rates (all else being equal).

I agree charge and discharge have the same thermal and degradation effect on the EV battery. L1 and L2 charging is wayyyyy down on the list of things we should worry about when it comes to battery preservation.

If you really want maximum battery health then avoid DCFC and if you must, then the lowest charge rate is best. Nobody wants to hear that though. Everybody wants the fastest DCFC rate possible and battery health be damned.

High levels of regen also damages the battery. But again.....everyone wants 1 Pedal driving with max regen levels without understanding how it affects the battery.

0-60 sprint's are not kind either. I can demonstrate this on my FFE. Not that it is super quick but the principal is the same. Here in Phoenix during the summer it can be 115 degrees or more. I drive around with A/C on of course and it works fine. However, I have to be careful not to accelerate too aggressively because the battery temp will increase and then the car will redirect all the energy to the chiller for the battery and none to the passenger cabin. A/C will blow warm for 30-60 seconds or so until the battery temp stabilizes.

Point being that how we drive the vehicle is just as important to battery health as how we charge the vehicle and even how we park it in the heat.
I'm new to this game. Just got my FFE a few weeks ago and it's my first EV. So don't hold my ignorance against me... why is regenerative braking hard on the battery?
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