Official Answer
When charging multiple batteries connected in series, each battery must be charged by a separate dedicated bank on the charger that provides an output voltage and charge profile that matches the requirements of each individual battery being charged.
For example, three (3) 12V batteries wired in series to produce 36V output would be charged by a three (3) bank charger with each bank of the charger outputting the appropriate 12V output voltage and charge profile for each battery connected in series.
Answered by Odin
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