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jbakuwel asked

Matching charging parameters Multi with LFP batteries (and ESS)

Hi all,

The battery manufacturer of a system with LFP cells states:

"0.5C constant current charge to 3.65V for cell, then switch to constant voltage charge until
charge current declines to ≤0.05C"

Which absorp and float voltages would be suitable in this case for a Multi (or MPPT for that matter)? I'm inclined to use 3.65V/cell for absorp (ie. 58.4V). The ESS assistant - when allowed to update the charge settings for LFP - sets absorp to a lower 56.8V and float to 54.0V.

Jan


Multiplus-IILithium Battery
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2 Answers
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seb71 answered ·

Maybe those are some special LiFePO4 cells, but in general I would not go over 3.6V.

So I would set the Absorption voltage lower than that, for some saftey margin.


Will you use a BMS?


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jbakuwel answered ·

hi @seb71. Thanks for replying. I've asked the battery manufacturer for more clarity but am not holding my breath :-). Meanwhile I'm taking the safe approach and not going higher than 3.6V.

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