Battery Talk

[Rockfish9]

I also run a duel battery system, charging is controled by an ACR, one battery is just for the engine, the other for house loads.. because my run to the fishing ground is short, I fish at night and my engine is fitted with a 20 AMP alternator, my draw on the batteries often exceeds my input, i switched to AGM batteries when the wet cell batteries died (after 4 years).. AGM, have a higher amp acceptance rate than all other batteries and one of the lowest self discharge rate, they are tottlay sealed and can be mounted in any poistion except upside down...when I switched them out, i dropped from Group 27 to group 24... last season was the first one in memmory that i did not need to charge the house battery mid season.... when i put the charger on them this spring... they accepted next to nothing...that's never happend after a winter off...

[OLD GOAT]

I just installed an Interstate group27 deep cycle two years ago.
This is the second such battery. The first didn't swim very well.
I only have the one battery on board.
Do you think I should carry a second for offshore dreaming???

[piemma]

Originally Posted by OLD GOAT

I just installed an Interstate group27 deep cycle two years ago.
This is the second such battery. The first didn't swim very well.
I only have the one battery on board.
Do you think I should carry a second for offshore dreaming???

I personally would never run without 2 batteries. When I anchor up or when I drift and shut the motor off I switch to battery 2 to run all my electronics. When I get ready to fire up the motor I switch to both so I always have one fresh battery to fall back on. To me it's cheap insurance.

[MakoMike]

Originally Posted by piemma

I personally would never run without 2 batteries. When I anchor up or when I drift and shut the motor off I switch to battery 2 to run all my electronics. When I get ready to fire up the motor I switch to both so I always have one fresh battery to fall back on. To me it's cheap insurance.

Wrong way to do it! When you go to start switch to battery 1 only, if you switch to both the current will flow to the weaker battery until both are equally charged. So if you switch to both and battery number 2 is dead, battery number 1 will start loosing charge as soon as you flip the switch, if you engine doesn't start on the first or second try you could be SOL. Unless you have battery isolaters on both batteries. After you start the engine you can switch to both batteries.