Sealed Gel type Lead Acid Batteries

Hi, i have a AEG UPS of 220KVA rating with TWO battery banks (2x 32 batteries of 12v, 100Ah) connected in parallel. Due to weakening of batteries in one battery bank, i removed one battery bank.

Then i connected only ONE NEW battery bank (32 batteries, 12 Volts, 115Ah) with UPS with changing any settings of charger, since it is a smart UPS.

However, 15 days of operation, one battery connected with Negative terminal of charger got ruptured.

What can be the causes?

1- Can it be over charging. As initially charger was charging TWO battery banks. Now same charger charged only ONE battery bank of 115 Ah.

2- Should i have changed Current OR Voltage values from charger.
In my opinion, it did not require change as voltage values will remain same for 12 Volts batteries & they will absorb only the amount of current till they are saturated.

3- Since batteries were new, so might be Voltage value had to be increased for first charge. Which did not happen. Can battery damage due to sulphation.

4- Why the battery connected with Negative terminal ruptured… Is it due to excess electrons during trickle charging?

I will request kind reply please for possible reason of battery rupturing.
Best regards,
Tariq Chowdhry.

If you were charging 2 sets of batteries in parallel and eliminated one set. You are charging the remaining set at 2X the rate. This might be excessive and cause the battteries to heat up and fail.

Thanks for your reply. Since 2 sets were in parallel, Voltage will remain same even after elimination of one set. So did the charge charged at 2 times the current, meaning it charged it to rapidly.
This battery was also the first battery out of 32 batteries connected in series with Negative terminal of charger. Does it also that during boost charge & subsequent trickle charge, excessive electrons accumulated and battery got ruptured and gel leaked.
Kind regards, Tariq