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[zap mc]

does anyone have any ideas on how to manually balance a Zero X battery pack?
earlier packs seem to have poor battery management and allow cells to become unbalanced outside charging perameters which causes the beeper to constantly sound and only get up to about 54v rather than the max 58V
we seem to have 7 rows of cells ( looking down the end of the battery with the end plate removed) which are 2 cells high ( but within a cardboard tube ) and 12 cells deep of Molicell IMR 267 000.

these are laced together with flexible battery strapping with 8mm nuts and loads of hot glue.

my idea was to decouple the rows and charge the rows individually to a certain voltage and reconnect them? Is this correct logic or am i missing something?

if found to be faulty it would not be possible to replace individual cells as Molicell now only produce IBR 167 000A as a replacement however it may be possible to swap cell  rows between batteries to cannibalise a good battery rather than pay $2000 for a new one

[sylvanascent]

I visited the factory about a year and a half ago, and asked them the same thing. Instead of charging up the low banks, you can bring down the high ones. You don't have to disconnect anything. Each of the 7 banks is really two banks, you can see the connection to the middle as a small hole about 2/3 of the way up the cell tube (looking from the end). You can clip a resistor (or a 6volt car headlight) to discharge a bank.

Sorry, not great instructions, but that's what they recommended.

[zap mc]

Thanks for the tip but my problem is that some rows are well down on voltage so are UNDER rather than over.
NOt really impressed with the internals of the cells either. each double cell is held together by an elastic band!! There is no actual physical connection between the cells and the steel strapping other than the tension supplied by the elastic band which looks like a bit of old inner tube and the shrink wrap tubing which is over the entire row. If the cells get hot this shrink wrap will become pliable and the connection could be compromised. NOt really throught through very well in my opinion. It seems that the linking of the cells by a flexible strap is the bit that is patented to prevent electrical breakdown under vibration.
I dont think many people are going to want to copy this particular design somehow!!
Will try and substitute a discharged row for a charged one and see if it takes a charge better. Each row should be about 8v but some are down to about 4v or 0v. When they are connected they manage to feed off each other but when disconnected they can fall to 0V which i think points to internal failure of cells.