battry set up in back

[Silverstx]

Howdy all.

I have just joined and am looking forward to picking all your brains !!!

I was wanting some info on the best battry to get. I am installing a box in the back to hold a battry for a car fridge ( 80L ). I have heard the marine deep cycle are the ones to get however there are many types ! could someone tell me what exact battry it is i would need to get ?

Cheers

 

[Old.Tony]

Welcome to the forum.

There are quite a number of threads here about battery setups, but let me summarise the choices for you:

"Marine" Deep Cycle - meaning an ordinary lead-acid maintenance-required black box with two posts that you need to keep filling up with fluid on a regular basis. They're an inexpensive choice, probably the best life expectancy for the $ paid, but capacity-wise they don't measure up to AGM or GEL. These deep cycles should not be discharged below 50% capacity (about 12.2V with no load)

Gel batteries are *******s that should be forgotten. They might be low-maintenance but you can't charge them quickly, you can't charge them at over 14.1V and you can't let them get too warm because if you do, the gel will bubble and that's bye-bye battery.

AGM batteries are as dear as poison (actually poison is cheaper in aisle 43 at Bunnings) but they are rugged (developed for military use), they can be charged at high rates and at the same voltage as your starter battery, some AGM batteries can be used to start your car!

Make sure that any cable between the front and rear is fused and always use some form of isolating device between the batteries so that power can't be drawn from the starter unless your engine is running.