Batteries connected series strings can be recharged by one charger having constant nominal charging voltage output because the nominal battery pack voltage.

When connecting or charging batteries series your goal is to extend the output of your batteries nominal voltage rating. to try and do this you wish to attach the POS (+) terminal of the primary battery to the NEG (-) terminal of the second battery. If there square measure solely 2 batteries in our series we'd then take a wire from the Negative terminal of the primary battery and a wire from the Positive of the second terminal to the battery charger.

Charging is based on current with resultant voltage as a secondary thought with relation to (let’s say) the battery. Once the charge has cause a voltage potential to rise to some level, a circuit can conclusion the charging method so “trickle” a little current in associate degree ON-OFF basis to take care of a given voltage across the battery.

The positive of the primary battery and negative of the second battery don't connect with every other! The series configuration doesn't increase your amp hour capacity; it solely will increase your voltage output.
If you wish to attach over 2 batteries serial, you'd build the subsequent adjustment. rather than connecting the POS (+) of the second battery to the charger, you'd connect it to the NEG (-) of the third battery. you'd continue this positive to negative pattern till you reach your last battery. The POS (+) of the last battery within the series can connect with your application / charger.