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redmcc avatar image
redmcc asked

BYD B-Box Pro Charge Current Limit and Temp

I've been having issues with cold weather and installed mini-pad heaters onto pairs of battery (20 BYD batteries / 10 heater pads). The temperature has responded well and is now sitting around 20 degrees. Unfortunately, the Charge Current limit is still limiting things (sitting in the 2-14 degree limit range).

I've even given the BMS controller a heater pad (just in case)...

Any suggestions?

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battery charging
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2 Answers
Alexandra avatar image
Alexandra answered ·

@redmcc

If you have optimised with battery life this also affects cold charge.

Try switching it off. I get the same issue when someone turns the air con down to artic temps in our one install.

Charge derating from the battery side is usually is under 5°C.

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Matthias Lange - DE avatar image
Matthias Lange - DE answered ·

The charge current can also be limited due to a cell imbalance. What is the highest/lowest cell voltage?

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Alexandra avatar image Alexandra ♦ commented ·
There could even be imbalances between packs depending on wiring and current share setup.
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