Does a dual battery setup need to have identical batteries and crank amps or simply need to be 12v?
any other suggestions?

 

If you just clamp two batteries together, the worst battery voltage wise will be a drain on the stronger battey. One larger battery would be a better idea than dual batteries. Dual battery set ups need switching circuits to keep a weak battery from removing charge from a stronger battery and to aid supplying power when the load is heavy.

 

What are you using the dual batteries for?

 

nothing in particular. I just happen to have extra batteries in my garage that arent being used for anything.

 

Then I wouldnt bother. Or if you absolutely must, I would isolate the 2nd battery so that it is not drawing from the main starter battery and only use it for accessories or to jump the main battery if it were to die.

 

thats what I was thinking. but they're dif sizes so I wasnt sure.

Thx

 

https://www.optimabatteries.com/expe...es-in-parallel

 

Ahh thx for that, but I'm thinking an isolated battery could work. I guess I could always still mount an extra battery as a spare and charge/wire them separately. Just also looking for options others might know that I'm unaware of.

Thx

 

Look up "perko switch".