12v Wheelchair Sla Battery

Does a thicker wire mean an increase in resistance, decreasing the current and voltage of the source?

The wires I am to use are 10 AWG, however, I have 6 AWG wire my question is, does this subtle increase in resistance/thickness/current skew my voltage/current?

I have wiring two 12v 24AH SLA batteries, used by two 24 Volt wheelchair motors, they draw a max of 20 Amps if that makes a difference

Also, what rating of fuses/circuit breakers should I use, and on what rail (GND, or V+?)

Thicker wire has LESS resistance.
The 6 AWG or thicker would be the one to use.
If the peak current is 20 amps, you will need a fuse/ breaker around 25A.
It might be placed in either the neg. or pos. rail, but the pos. rail is more conventional.

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