Switching a multi-cell series circuit to parallel for charging

Thread Starter

r3uben

Joined Jan 20, 2019
2
I am attempting to build a simple DC circuit that runs with 4 x 18650 li-ion cells. I would like this circuit to run in a series configuration to drive an audio amplifier, but then switch to four separate parallel circuits for individual cell charging. As an electronics noob, the only solution I have come up with so far is to have 4 DPDT switches manually switched. There would be a 4 cell battery protection board for series operation, but not when parallel as each cell will be isolated. There must be a much more elegant solution to achieve this? Thanks!
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oz93666

Joined Sep 7, 2010
737
Since you already have a protection circuit for serial operation , the obvious way to do this is to leave them serially wired and charge all together in series . No need to disconnect anything , just have a socket which allows the connection of a 18 to 30V supply to charge . The protection circuit will keep the charging within correct limits , and terminate charging when cells are full and balanced.
 

Thread Starter

r3uben

Joined Jan 20, 2019
2
Since you already have a protection circuit for serial operation , the obvious way to do this is to leave them serially wired and charge all together in series . No need to disconnect anything , just have a socket which allows the connection of a 18 to 30V supply to charge . The protection circuit will keep the charging within correct limits , and terminate charging when cells are full and balanced.
Thank you for your reply. I was under the impression you could only balance charge when in parallel? If at all possible, I'd prefer to use these four chargers as I already own them - they can charge at a maximum current of one amp for a single 4.2li-ion cell.

Would it be easier to scrap that and buy a higher current li-on charger that can charge 4 cells together?
 
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