Deep cycle battries and standard car battries

[jimmbo]

While the Optima looks cool, they have been a bigger Headache than they are worth. If you ever leave the lights on at the Airport, and come home to a dead Battery, boosting will start the Car and the Alternator will keep it running, however the Battery will not accept a Charge. You have to go thru a Process involving another Battery to get a charge into them. A real PIA

 

[airshot]

Taking good care of a battery goes a long way!! Many years back I foubd out about battery " maintainers" a type of trickle charger that helps batteries last longer. These were recomended by the engineers at the battery plant. I started using them for my boat and my motorhome batteries especially during the off season. From that point my average battery life almost doubled !
Even some of my cheap batteries were lasting about 5 years where they were lasting only about three years. My better quality batteries were going 6-7 years, well worth the 30-40 dollar cost of the maintainers. The boat I bought over the summer has built in chargers with maintainers. The current batteries are 4 years old with no sign of loosing power. I have two group 31 deep cycle for the trolling motor, another group 31 as a house battery and a smaller group 24 starting battery. I need these to be taken care of as well as possible, it is gonna cost me a fortune to replace them !!!

 

[JimS123]

Taking good care of a battery goes a long way!! Many years back I foubd out about battery " maintainers" a type of trickle charger that helps batteries last longer. These were recomended by the engineers at the battery plant. I started using them for my boat and my motorhome batteries especially during the off season. From that point my average battery life almost doubled !
Even some of my cheap batteries were lasting about 5 years where they were lasting only about three years. My better quality batteries were going 6-7 years, well worth the 30-40 dollar cost of the maintainers. The boat I bought over the summer has built in chargers with maintainers. The current batteries are 4 years old with no sign of loosing power. I have two group 31 deep cycle for the trolling motor, another group 31 as a house battery and a smaller group 24 starting battery. I need these to be taken care of as well as possible, it is gonna cost me a fortune to replace them !!!

"Taking good care" goes without saying. But I've always been leary of trickling.

Years ago I had one and that battery lost fluid over Winter and I found that battery to have a shorter life. I realize it may not have been a good charger, so maybe that had something to do with it. Regardless, with 3 boat batteries and 2 tractors, I'm not about to use 5 chargers.

My boats run maybe once a week. So, they are idle much of the time. Summer discharge is minimal. In Winter I charge the first day of the month, every month. I usually get about 8 years out of a "good" battery. I don't buy the stuiff at wallyworld.

Here's an interest story. I also have a classic car that gets driven very seldom. I don't remove the battery over Winter, nor do I bother charging it (it's parked spot is not convenient). I inspect it early Spring. It's usually low, but it always turns the engine over and a little driving and it's OK. A few years ago I got to thinking that the battery is probably old so maybe I should replace it as preventative maintenance. A check of my service log book showed that DieHard to be 26 years old. I replaced it anyway.

 

[airshot]

If your battery is low, a good charge is required to get it full as quick as reasonably possible. Oncevthe battery is fully charged then switch over to a trickle/ maintainer charger. According to the battery engineers I know, the maintainer keeps stuff from collecting on the battery plates. Don't remember what the stuff is called but it can shorten the battery life if left to build up. A maintainer is designed to remove that stuff by putting the battery thru some cycles. For many years I used walley world batteries, about 4 years tops for battery life. With the maintainers that has increased to 6-7 years. I have been using them for more than 20 years and have had great sucess with extending the batteries life. Used on on my SxS with those little atv sports batteries which normally last a max of three years. I use mine hard by winching out of mud in summer riding and using the winch and extra lights for plowing snow in winter. Just replaced the battery last fall...still worked well but it was noticibly loosing power with the winch running and didn't want to get stuck in the backwoods with no winching power. My own personal experience has proven to me that maintainers work....not talking about a cheap trickle charger but an actual battery tending device. I use " Battery Tender" and also a couple harbor freight battery "maintainers" ...probably have 5-6 of these for all the battery applications I have.

 

[tank1949]

Someone told me they were worth it so I switched. Cars, multiple boats, etc. Then, I found out they weren't. With Autozone wet cell batteries I'm getting 8 years or so. The AGMs gave me less than 6.

I thought about attaching a trickle charger to each of my boat's batteries. But, I don't know if it would increase life vs the expense.

 

[dingbat]

I thought about attaching a trickle charger to each of my boat's batteries. But, I don't know if it would increase life vs the expense.

The self discharge rate of a healthy lead acid battery is quite low. A healthy, fully charged battery should go 3-9 months between charges, depending on the temperature, for a battery to drop to 70% capacity before needing topped off again.

The two biggest killers of batteries are exceeding the recommend “Depth of Discharge” (DOD) of your battery type and the failure to replenish the discharged current in a timely fashion

For batteries routinely discharged to 50% DoD (12.06V) its cycle life is about double that of a battery discharged to 80% DoD (11.5V) In turn, a battery discharged to 10% DoD (12.5V) will last five times longer then one taken to 50% DoD routinely.

Sizing your battery(s) to stay above the 50% DOD threshold and topping them off at the end of the day will pay dividends

 

[Lou C]

Also, don't trust your dash gauge 100% and assume that the alternator is fully charging the battery, check it with a digital voltmeter, you will find under or overcharging that way.

 

[airshot]

I thought about attaching a trickle charger to each of my boat's batteries. But, I don't know if it would increase life vs the expense.

The real advantage is to have one with a maintainer cycle on it, otherwise a plain trickle charger might be questionable with the cost.

 

[airshot]

Not a fan of starting batteries in marine applications. Deep cycle are just so much more robust than starting batteries

Run twin grp. 27 deep cycle batteries. Provides 1,500 cranking amps (750 ca, ea.) and 176 Amp Hours. Have averaged 10 years of life over the last two sets of batteries?

By tying two batteries together, you have taken the heavy amp draw off of each battery and spread out the load between the two. Not a bad idea if you have the room and your boat can handle the extra weight....

 

[bruceb58]

Certain newer fuel injection ignition systems have a minimum CCA/MCA spec. My 2017 6.2L Mercruiser spec is 800CCA.

My engine also has a dedicated power line form the ignition/fuel injection system straight to the battery to reduce voltage drops. I use AGM batteries that meet this spec. Many so called "Marine/RV" batteries do not. For example, Interstate 24 or 27 series RV/Marine do not.

These are the batteries I use:

Duracell AGM Deep Cycle Marine and RV Battery , Group Size 31 - Sam's Club

Buy Duracell AGM Deep Cycle Marine and RV Battery , Group Size 31 : Marine Batteries at SamsClub.com

www.samsclub.com

 

[airshot]

I do know that these new electronic systems on newer engines do require a full battery charge. Have read numerous non start issues where the engine turns over fine by wont fire due to a low battery, and it doesn't need to be very low!!

 

[jlh3rd]

my new purchased 2021 merc.115 ct also required the 800/1000 rated battery.....I was told the same thing..