How do I connect 12 volt sealed lead-acid batteries in parallel?
Last Updated: 11/26/2013
By Petra Paulson
Make sure the batteries you're connecting are of the same voltage, capacity, and battery type. Failing to do so can result in shortened battery life.
Use jumper wire to connect:
The positive terminal on Battery 1 to positive terminal on Battery 2.
The negative terminal on Battery 1 to the negative terminal on battery 2.
Then connect the positive and negative wires to the corresponding terminals on your application.
doubles the Ah capacity of the batteries while keeping the voltage the same. For example, wiring two EnerSys NP5-12 (12V, 5Ah) SLA batteries together will retain a voltage output of 12v, but it will double the capacity to 10Ah. This wiring configuration is often used in scooters, backup power supplies, and laptop batteries.
Click here to see how to connect batteries in series.
Casil CA1240 (12v, 4Ah) SLA Battery