Multiple Batteries and Battery Isolator Question

[Mikeski]

RE: Which battery

I am thinking I may put a pair of golf cart batteries across from the factory battery in my 211 this winter. I pulled a loop for them in the amplifier power mains. Here is something an RVer buddy sent me, good reading.

http://www.phrannie.org/battery.html

[fyerfytr]

RE: Which battery

NautiqueJeff.
Will the stock alternator handle the load for charging two batteries? I was looking at either doing a switch between the two batteries or the isolator/combiner. I think I may do the isolator - sounds like less work after it is hooked up.
thanks

[surfmakr]

RE: Which battery

I thought I would share what I have picked up about charging batteries. I am not an expert by any means but I have been told that when charging batteries, combining them presents problems. The battery with the least amount of charge will not be charged effectively. The stronger batteries make the week one seem better than it is. This problem is even further complicated if the batteries are not similar (requiring different charge rates). So, I have been advised to not to use isolators but use Perko type switches and charge batteries or banks of batteries individually. If you have a bank of batteries make sure they are the same and if you have an isolator like Jeff make sure all of your batteries are the same.

On another note, many of the batteries I see posted on this site are high quality AGM combination starting and deep cycle batteries. These batteries still have thinly manufactured lead plates to give them a high cold cranking capacity but are not true deep cycle batteries. They are better than batteries designed just for starting engines and because of the Absorbed Glass Mat technology they can be mounted in various ways, accept faster charge rates and last much longer. I would consider using true deep cycle AGM batteries to power the stereo like ones from Lifeline manufactured by Concord and an Optima or Odyssey as your starting battery with a Perko switch so you can direct the alternator to charge the banks of batteries separately. This will give much longer life to the batteries and eliminate some of the challenges. Just my .02 cents

[fyerfytr]

RE: Which battery

Thanks for the input, I am planning on doing the deep cycle batteries in the setup. I am afraid that if I have both batteries hooked up and charging that it may fry the alternator, so the benefit that I see with the switch is that you can charge them individually if you want. I have alot of drain from the amp/capacitor setup and have been left with a dead battery after sitting and listening to the stereo after a couple of hours, so I need to have a backup battery that I can just switch to when this happens.
Mark

[surfmakr]

RE: Which battery

Thanks for the input, I am planning on doing the deep cycle batteries in the setup. I am afraid that if I have both batteries hooked up and charging that it may fry the alternator, so the benefit that I see with the switch is that you can charge them individually if you want. I have alot of drain from the amp/capacitor setup and have been left with a dead battery after sitting and listening to the stereo after a couple of hours, so I need to have a backup battery that I can just switch to when this happens.
Mark

Mark,
You most likely will not fry your alternator, It will work pretty hard if your batteries are really low and depending which alternator you have will dictate how long it takes to charge the batteries. If you use the Perko you can controll what is going on. Good luck