question

nigel avatar image

BYD B-Box Pro Charge Current Limit and Temp

Hi, The BMS is reducing the charge current when the battery temp is still above the 15 deg threshold. Currently reporting battery temp at 16 deg so charge current shouldn't be limited but it looks to of limited the charge current at the point when the battery temp dropped from 17 to 16 deg. Any ideas why this is happening?

byd-b-box-pro.jpg

Thanks

Nigel

BYD
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2 Answers
Guy Stewart (Victron Community Manager) avatar image
Guy Stewart (Victron Community Manager) answered ·

There might be an individual cell in the system that is still below the threshold, so blocking the total system, once it is 17-18 degrees they should all be clearly above 15 degrees and fully charging.

Keep an eye on it, and see if that is the case. If not and the temp gets to 18 degrees and it's still limited, there might be something else to investigate.

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nigel avatar image
nigel answered ·

Thanks Guy. Your explanation seems to hold true. Once the temperature is in the region of 16-17deg I am consistently getting full charge. The batteries are in a secure container and well insulated with a small bar heater to maintain the temp. I am guessing that there may be a temperature difference between the cells and the top and the bottom hence why it needs to be around 16 to 17deg before full charging is possible.



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