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Discussion Starter · #1 ·
I don't want to look stupid and it may be too late (LOL), BUT, I have finally got around to hooking up my two volt packs. The problem is, they are at vastly different SOCs so I am looking for a cheap way to bring the lower one up the the same voltage as the higher one before I do the final hookup. I have no chargers yet so looking for some cheap way to do this. Any ideas? It may only be used a couple times.
 

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Discussion Starter · #3 ·
Specify your voltages for each side:

lowest safe, highest safe, actual at the moment
Volt half packs which I am paralleling, part one of pack A is 159 and part one of pack B is 184. Exact same configuration of cells. I want to get them to be close in voltage
121080
 

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You did not fully answer.

But finding a load to bring the higher one down in a controlled manner

will be easier than v/v

unless an adjustable PSU or DC-DC converter is handy to borrow nearby
 

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Agreed, at that level you can rig a load using incandescent light bulbs to bring the higher one down. It may take awhile but doable.

Sent from my SM-T380 using Tapatalk
 

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Can you get access to the individual cells, for example through the BMS connection? If so you could use a small charger, say an IMAX B6, to charge them all individually. Might take a while, the max output is something like 5A but they should all be at the same SOC in the end. The IMAX B6's use a voltage divider to measure the battery voltage, in general, the more you pay for the charger, the better matched those resistors and so the more accurate the voltage. As an alternative, you can reflash the charger with the Cheali Charger software - https://github.com/stawel/cheali-charger - which allows calibration.
 
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