Batteries Options

[Bees Knees]

I need to buy another battery for my boat just installed the battery switch.

Just for my accessories. Do i need same size/smaller/larger than my existing?

I need to get it tomorrow. I'm off to Currarong Friday.

Advice would be great

Thanks in advance!! BK

[It'l Do]

BK,

What batteries did you end up installing?

How are you going to run your switch? If in "1" then how will you keep your second battery charged?

Read all this and heard all this before in 4x4 clubs. But what the real world has been doing for years is running then in parrallel with and isolator for starting (e.g. solenoid or electronic relay). And used them until the the batteries would had nothing left in with the winch running. And yes the start battery did not like it.

If you run a start and deep cycle battery, the batteries internal resistance will control the charge. The alternator keeps putting out 14-14.4 volts so they keep receiving charge IF THEY NEED IT.

Question how much capacity has you alternator in your boat got?

Biggest problem is when the deep cycle is run low because the alternator will shove full capacity into it and I have a hunch that it will not be 70Amps+.

That's my 2 cents.