I assemble my service battery from eight LiFePo4 cells of 3.2V 300Ah. To charge them for the first time, I use a lab power supply and set it to a constant voltage of 3.65 volts.
I have two power supplies of this kind, one with a maximum current of 40A and a smaller one that can deliver a maximum current of 5A. I start with the larger one for each cell, and once the current drops below 5A, I switch to the smaller one to complete the charging until the current is almost zero.
After filling all cells in this way, I connect them in parallel to create a massive battery of 3.2V and 2400A. It undergoes another charge with 3.65V until the amperage is almost zero again.
Once that is done, I assemble the battery by connecting the cells in series, resulting in a 24V 300Ah service battery.
All in all, this is a lengthy process spanning several days during which I don’t leave the battery unattended, and I record the current strength every hour.
To avoid twiddling my thumbs during this time, I’ve worked on my website again. See next post.
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