Bogart charging LiFePo
So, here is the response:
In that video from BB they say it is the passive mechanism of the BMS that balances the cells. That is what had me confused. There is no mechanism in a passive BMS to balance cells in series.
It is also not higher voltage that balances the cells. The cells will all rise at their own rate based on their capacity. The first cell that hits the voltage trigger for the BMS will shut the battery charging off. The remaining cells will just not be completely full. A very small difference anyway if you could balance and fill them all equally/fully.
A 12v 4 cell LiFePO4 battery is full at 13.6-13.7 with a very small amount left possible after that. I think the reason why companies like Lion and BB chase these higher voltages is the faster charging rate that can occur towards the top end of the charge cycle due to most controllers that stage down the charging rate as the battery voltage approaches the battery full SOC programmed into the charger.
The narrator in that video is Denis the company CEO. The e-mail response was from an engineer there. I am still not satisfied with their explanations. I was pretty sure that their BMS had nothing to do with balancing as the video mentioned but I am also fairly certain it is not charging voltage either that is miraculously balancing cells in series. There is no way to explain that in my mind.
But, I am happy to learn if I am wrong. :)
I do appreciate that they responded to a fairly technical question.
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