How to add an Aux. Battery?
 

I'm not sure if I have posted this in the right section - if not - Mods please feel free to move.

Okay, now that I have that out of the way I have a "possibly" simple question.

My 2001 Mariah Diablo 180 is in need of a new Battery. It currently has a single battery setup with a dual purpose marine starter battery (I will need to replace this battery - as I gave it to the gentleman that purchased my RV).

I also own an Interstate Deep Cycle (gray battery). This battery was given to me by a family member who recently replaced all the batteries on his bass boat. This battery holds its charge, is very clean, and looks to have some life left in it. I would like to add this Interstate battery to my boat as an aux. power source. (I purchased an over sized battery box for it).

My questions is - what is the best way to add an additional battery?

In the past I have always shut the boat and all accessories off when not running (including our stereo which sucked). However, I just bought new kicker speakers and a new to me Clarion CD player - so i'm inclined to think that the batteries may get more use when sitting... now that I have a way to play "good" music. We also plan on spending a few nights on the water (not over night) but will be on the water for longer periods of time with the lights draining on the battery.


How should I wire this second battery?

Can I just Parallel wire it?

Do I need to replace my battery switch? or is it capable of running 2 batteries?

Should I buy a gauge(s) for the batteries?


I'm not planning on running the radio for hours at a time - and I also plan on swapping all my incandescent bulbs for LED to lower my power usage. I have a small trickle charger that I could wire up in the boat - but I would like to avoid dragging out an extension cord every time i'm home.

Any help or suggestions is greatly appreciated. I just don't want to get stuck on the river with a dead battery. I don't even have to add the interstate - but since it was a freebie with life, I thought it might add some extra insurance when out on the water.


Thanks again!

Nick

Re: How to add an Aux. Battery?
 

They make specialized kits for this. It also comes with an ACR system that combines the batteries for charging and starting, and isolates them when not. It won't allow you to drain the battery completely down, which is nice.

Here you go:

BLUE SEA SYSTEMS "Add-A-Battery" Dual Circuit System at West Marine

Re: How to add an Aux. Battery?
 

This is very helpful. I've been looking for something just like this. Thanks!

Sent from my DROID RAZR HD using Tapatalk 2

Re: How to add an Aux. Battery?
 

That is an interesting product. I like the idea of it automatically switching them for charging purposes.

Without adding a switch, can I safely wire these in parallel? If so, would that expand my battery capacity, and would my alternator be able to charge both?

I have also looked at this product:PriorityStart - 12-Volt Marine Information
Supposedly it monitors your battery and shuts it off before it gets to low, allowing you enough juice to start your engine. I think a few different companies make these.

Anyways - i'm still mulling everything over in my head. I really like that switch kit, it looks like a great product.

I'm just trying to weigh all my options. I just have this fear that we'll run our battery dead when sitting on the river at night (like when we go to the sternwheel festival and watch fireworks). We really only go out a few times a year at night - but it would only take 1 time to ruin boating for my wife and kids.

Thanks again!

Nick

Re: How to add an Aux. Battery?
 

I am also looking at this product - Battery Brain UK Products, Purchase and Check Out

It's like the Priority Start, but is had a remote (which would be handy when parking at the dock).

Has anyone on here used one of these products?

Re: How to add an Aux. Battery?
 

Nick, these aren't life altering decisions. Just pick the one that does what you want it to do and that your wallet can afford. :rolleyes:

Re: How to add an Aux. Battery?
 

Why not just get the Blue Sea Kit and you'll get a switch AND the ACR? If you're internet shopping savvy, you can pick it up for quite a bit cheaper than West Marine...

Like here:
Blue Sea 7650 Add-A-Battery - 7650 Blue Sea

Priced even less than the "Priority Start System".

The "brain" system is UK based, so you'll be paying 69 pounds for it, which is around 108.00 today, PLUS you'll have to factor in the costs of the international shipping, and the waiting time... Plus I'm not so sure of the advantages of the remote system. If I were someplace where I'd be concerned with someone stealing the boat, I'd probably go dock somewhere else, or sit some place to keep a close eye on it.

Re: How to add an Aux. Battery?
 

If your that worried about your battery going flat then carry a boost pack!
They no bigger than Mrs B's hand bag (don't ask) and I can start my 4.3 on one with a flat battery (again don't ask!) no problems.
keep life simple, especially out on the water...

Re: How to add an Aux. Battery?
 

I remember posts from the past where members complain that their boats list a bit to one side or the other. If you add another battery, you're going to have a lot of weight in the rear starboard side of your boat. The boat floating with the right rear corner lower in the water than the left rear might be an unintended consequence of adding an extra battery. Since I'm kind of anal, a listing boat would drive me crazy!

Re: How to add an Aux. Battery?
 

m&m brings up a good point. I'd spend some money on longer cabling and mount the second battery in a case on the port side to balance things out.