Can I goose the top balance with my charge controller?

Yurtdweller

Solar Enthusiast
Joined
Nov 23, 2020
Messages
131
Can I build a 4s battery with BMS, then charge the whole series with 30 amps from my mppt solar charge controller until I get one cell to about 3.55, then go to top balancing with the bench top PS? I want to do it this way, because I currently operate off a 100ah LiFePo4, and I cannot simply let a btps run for days. I expect the cells to be very well voltage matched when they arrive.
 

Bob B

Photon Sorcerer
Joined
Sep 21, 2019
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3,808
Sure ..... that is a good method.
The only downside I can think of is wear and tear on the terminal studs from re-configuring.
 

shadowsteve

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Feb 11, 2021
Messages
205
That's what I did with mine. Made the 4s pack and charged it thru the BMS with a car charger. Then I reconfigured it and top balanced in parallel. My battery box config allows me to put the cells in parallel (using supplied busbars) or series without unclamping them
 

Yurtdweller

Solar Enthusiast
Joined
Nov 23, 2020
Messages
131
Thanks guys. I thought so, but I'm self-taught, and with so much different info out there, I just wanted to run this idea by the forum. My cells are in Long Beach, now, and I'm making final preparations. :) I'm seriously considering rolling down to the Efest Electric warehouse in Houston to get a separate set of cells to try this process, so that I'm sure I'm not futzing up part of a 16 cell batch:)
 
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