Parallel Batteries / Dual Batteries / Early 911s

[72doug2,2S]

[72doug2,2S]

Changing out my AGM batteries in the 1972 Batteries were from 2014, as they are 8 years old and won't keep a charge. Is there a method? Does it matter which one is connected or disconnected first?

Positive, then negative ect..

[72doug2,2S]

I found these AGM motorcycle batteries for under $50 each.

[E Sully]

Originally Posted by 72doug2,2S

Changing out my AGM batteries in the 1972 Batteries were from 2014, as they are 8 years old and won't keep a charge. Is there a method? Does it matter which one is connected or disconnected first?

Positive, then negative ect..

It is safest to disconnect the negative terminals first, then the positive. This prevents risk of accidentally shorting the battery if the wrench were to contact ground when taking off the positive terminal.

[Zuffenwerker]

This is interesting. So when 2 batteries in parallel are charged the current (not voltage) is split between the 2 batteries. That means the 2amp trickle charge is only 1 amp per battery. Sounds like a good slow charge for these would be 4 or 5 amps. Although..they are smaller batteries than normal.