Deep cycle battery life

Google Solargizer and check out their Pulse technology. A little pricey up front but I get 4-5 years out of my Sams Club batteries. Good luck.

iowa_josh wrote:

I don’t know if an automotive load tester is going to give you good info about a deep cycle battery.

I do.

ssaamm wrote:

He said they are fine, but they are starting batteries not deep cycle.

That’s your problem. There are deep cycle batteries which are designed for trolling motors and there are cranking/starting batteries which are not designed for trolling motors. They are for starting the main outboard, electronics, pumps, lights, etc.

biggill wrote:

Depth of discharge is as important as keeping the battery charged. All batteries are rated for a certain number of discharges to a certain discharge level. If you regularly discharge them to 25% or less, you either need bigger batteries or you need to accept the fact you’ll be buying batteries every couple years.

^^^ This.

I’ve been doing a lot of research on solar power for an off the grid cabin and few know as much about batteries than solar techno geeks.

Bottom line is exactly as Matt says. The farther you draw down a lead acid battery, the shorter it’s overall service life. This applies regardless of battery brand, at the end of the day, all lead acid batteries are the same in this regard. Charging does have some effect, but the number one factor in overall life is draw-down percentage.

If you want longer overall battery life, you need a higher capacity battery so you don’t draw it down as far between charging cycles. In solar power, to achieve maximum longevity of the batteries (the most expensive component of the system, BTW), the general rule of thumb is don’t draw down more than 20-30% on a yearly average basis. Once you start drawing down 30+%, battery service life goes off a cliff is what I’ve been ready across multiple sources.

Grouse

So is what we are saying here is to have a larger capacity battery and charge after each use to be ideal then?

I JUST replaced my 24 batteries for my boat last week. I was amazed to see that they were both purchased in 2013!! I seem to have great luck with batteries. Replace the starter battery which runs my depth finders also – 2014 on those. I must be living right. Hope these new ones last so long.

John Rasmussen wrote:

So is what we are saying here is to have a larger capacity battery and charge after each use to be ideal then?

That is what I do.

Ripjiggen wrote:

<div class=”d4p-bbt-quote-title”>John Rasmussen wrote:</div>
So is what we are saying here is to have a larger capacity battery and charge after each use to be ideal then?

That is what I do.

Yuuuup

Thanks, also another question. I run a 24 in series with a 27, due to lack of room in one compartment someone told me this is not ideal. Any thoughts?

Not ideal. Pointless to have the larger battery you will only get the power and capacity of the smaller battery.

Ok thanks Ripjiggen. I guess I will have to go with 2 24’s or figure something else out with my compartment.

If you are going to upgrade go to AGM’s. Lead acid batteries are a pain in the ass to maintain and have a much shorter lifespan. Spend a little more and they will pay off.

I have interstate group 27’s on a 36 volt system now. In less than a year one has gone bad and I need to add water every 60 days. I put some stress on them on the river but when I had AGM’s on the old boat I never had an issue in 4 years. I constantly run the interstates below 25% so if I get 3 years I’d be surprised.

The dealer that rigged my boat would have been more than happy to sell me AGMs they said they have crunched the numbers and you are better off with lead. On even a 24 volt system the average lake angler is not running their battery below 25%. I tip my hat to Matt, guessing he is a little more hard core than meself.

No doubt a trade off in whether you should purchase the higher priced AGMs compared to standard lead like interstates. This probably comes down to personal preference to be honest.

I have been buying the recycled batteries from Interstate or the batteries that have been pulled off the shelves due to past shelf life. Interstate resells them and they test them prior to selling. I get 2-3 years out of them typically but I only pay like $55-60 for a 29 or 31. I feel that is a fair deal.