Battery wiring

Battery wiring

In case more than one battery is needed it’s important to connect the wires to the batteries of the storage bank in the right way and to understand what is the result of that action. First of all it is very important that batteries are all the same size (Voltage and Ah) and the same age (a 6 months old battery is not the same age as a brand new one).

Batteries in series:

serial

First the serial connection, the positive terminal of one battery connects to the minus terminal of  the other.

Results:

  • Voltage adds up so 2x 6V battery becomes 12 Volt
  • Amp-hours stay the same but now on higher voltage so 200Ah on a single 6V battery will now become 200Ah on 12V
  • Total storage power doubles (compared to a single battery)

 

Batteries in parallel:

parallel

Next setup is parallel, the positive terminal is connected to the postive terminal of the other and the minus terminal is connected to the minus terminal of the other. Be sure to always take the power of both ends of the chain, not from one and the same battery.

Results:

  • Voltage will stay the same, so 2x a 6V battery will stay 6 Volts
  • Amp-hours will double, so 2x 200Ah will become 400Ah on the same voltage
  • Total storage power doubles (compared to a single battery)

 

Combined as a large bank:

combined

A very common setup is a combination of parallel series, in a serie the positive terminal of one battery connects to the minus terminal of  the other just like before. The positive terminal of one series is connected  to the postive terminal of the other series and the minus terminal of one series is connected to the minus terminal of the other series. Be sure to always take the power of the cross ends of the combination, not from one and the same series.

Results:

  • Voltage adds up so 2x 6V battery becomes 12 Volt
  • Amp-hours will double, so 2x 200Ah will become 400Ah on the new voltage
  • Total storage power quadruples (compared to a single battery)

If batteries are added, the principles stay the same.
Large combined setup with 12 batteries can be downloaded as PDF

Info: Conductor sizing