Series vs Parallel  Connection, Differences, Advantages, Disadvantages.

When batteries are connected in series, the positive terminal of one  battery is connected to the negative terminal of another battery.

The voltage adds up while the capacity (ampere-hours) remains the same.

Batteries in Series

When batteries are connected in parallel, the positive terminals are  connected together, and the negative terminals are connected together.

The total capacity of the battery bank increases, providing longer runtime.

Batteries in Parallel