Home Forums Hunting & Shooting Hunter's Campfire Trolling Motor Deep Cycle Battery

This is what I said earlier about misleading articles about discharging. It's hard to know if they mean discharging below 80% of full capacity or 80% of the power used up. This from Trojan Battery says don't use up more than 80% of the power.

Discharging batteries is entirely a function of your particular application.

However, below is list of helpful items:

Shallow discharges will result in a longer battery life.
50% (or less) discharges are recommended.
80% discharge is the maximum safe discharge.
Do not fully discharge flooded batteries (80% or more). This will damage (or kill) the battery.
Many experts recommend operating batteries only between the 50% to 85% of full charge range. A periodic equalization charge is a must when using this practice.

When using a wet, flooded battery. Some tips:

Use a deep cycle charger. They charge slow at a lower charge voltage rate. Anyone selling you a "fast" charger is selling you problems.

The battery is charged when a hydrometer says it is. Not when the gauge says charged, not when the "smart" charger says its charged and not when the worthless on board system shuts off... It will also show you how low the battery is discharged after use. Rock Chuck's info above is good advice on how deep the cycling should be taken.

Anyone who says "the battery was fully charged when I put it away" 99 times out of 100 have never put a hydrometer to the battery and have no idea if it really is charged or not. Automatic chargers make this problem worse...

AGM's have more available cycles, but can also discharge to a lower open current voltage. Keep that in mind. They will also charge faster when using an appropriate AGM charger. Their discharge rate is also slower unhooked from the unit in storage.
Most AGM deep cycles are pretty decent, but they aren't a panacea to any problems that people have with wet flooded batteries. I find them even less forgiving in a lot of ways, and more expensive when you screw up.
The Optima is one to avoid.

I would say 99% of the deep cycle marine batteries go bad because people ruin them, rather from any legitimate use.

I once ruined a good trolling battery. I forgot to unhook the battery cable from my trolling motor. I guess I bumped the tiller handle at home and turned it on low. It ran the battery completely out and it never took a full charge again.

If you discharge a battery 100 percent you cut it’s life in half.

AGM’s are made do discharge less than that

You probably could have saved it by hooking up another battery parallel and charging.

Most chargers today will not charge a battery if its below a certain voltage range. Most 12 volt chargers won't charge 6 volt batteries as a protection device. In turn, they won't charge any 12 volt battery much lower than 8.5 volts, so the charger needs "tricked". I've charged batteries reversed polarity charged, then discharged to zero and charged with correct polarity using this method.
We did have a charger that was for commercial use that would either charge the battery or blow it up; it didn't care what resistance it had or didn't have, within reason.

This is the reason I find wet flooded batteries more forgiving. A deep discharge isn't a death knell if you know what you're doing. Discharging them down to nothing and recovering them is a lot more successful than a run down AGM that you have no idea the sate of charge of each cell. All you have is a voltage reading, which means little.

I have had good luck with the Wal Mart Ever Start Maxx deep cycle batteries group size 29DC and a Minn Kota 3 bank 5 amp per bank charger. I have 3 of these batteries in my boat hooked in series . I want to be able to troll all day on the no gas motor lakes and still be able to get back to the dock at the end of the day. So far so good.

You have a 36v trolling motor?

I have a 36v system on my boat plus starting battery and had bad luck with Interstate's, the trolling motor gets more hours on it a year than the kicker. Batteries Plus has duracell's that are about $120 each and will test them right in the boat in the parking lot for you and warranty them quick.

I have a pair of 2150's in my boat (77 lbs each) and they are going on 6 years old. Pro Charger is kept plugged in 24-7, 365 days a year. Cry once and get the best.

This is the charger I use for all my battery charging. This is the older style Xantrex True Charge 10, In my opinion Xantrex are the leaders in this type of stuff but that is only my opinion. With the TC10 the gel setting is for gel batteries only you use the standard charge setting for the AGM, Gel batteries are charged at a lower voltage as the plates can't take the heat like other types of batteries.

If you watch Ebay you can get good deals on nthem now and then, the last time I watched I ended up with 3 of these damn things for $45.00. They made great gifts.

There are also multi bank model for charging more than one batter as well.

Battery’s plus is where I got my northstar pure lead type batteries.... they typically have good deals

Couple few more points:

Leaving some set it and forget it auto chargers on long term may kill your batteries. I killed three Trojan SCS Batts (36v minnkota motor) with a minnkota mk315 three bank charger. Supposedly safe. Boiled the water out of the batts. Better to plug in overnight and unplug.

Always charge as soon as you can. Never let sit at less than full charge if it can be avoided.

AGM batteries have a much lower self discharge rate and would be better to for longer term storage.

AGM batts such as odyssey actually require a high amp charger to condition the plates. A typical deep cycle charger will prematurely kill an odyssey battery if used in a deep cycle application. Use a charger recommended by the manufacturer.

Odyssey AGM and cranking batteries have identical guts and may be used for either.

Common dual purpose or department store deep cycles won’t take the same number of cycles as a good deep cycle lead acid like a Trojan.

These are the battery chargers you can hook and forget. I've used mine for 6 years plus and the only time they're unplugged is if we're fishing.

http://www.dualpro.com/

Chainsaw: As previously mentioned, discharging a lead acid battery below 50% shortens the life considerably. In 8 1/2 months storage I suspect they are self discharging below 50%. Hook up a solar panel to trickle charge while you are gone. I kept a small 1.5 volt solar panel plugged into a cigarette lighter that was hot even when the ignition was off in a vehicle that was used in Alaska for the same time you use your TX boat. Got good life out of the battery.
Another factor shortening your battery life is the intense heat your batteries are subjected to in the hottest part of the year in a storage building. Don't know how you fix that other than ventilation. Maybe a locked wired storage cage on the side of the storage building?

Yup, that's why I keep a little old fashioned manual charger. Charge with that long enough to build up a reasonable surface charge then continue with the automatic charger.

Automatic chargers switch to a trickle charge which cannot damage batteries when the battery reaches "full charge" voltage. But full charge voltage gets lower as the battery ages. So with pretty much used up batteries the charger never sees the programmed full charge voltage and keep pumping the amps, ruining the battery.

Note starting and deep discharge batteries have different full charge voltages, why it' important to use the right charger.

Thats true.

It also nullifys the notion of set and forget charging. There is a limit to it and eventually liquid loss and charger cycling will wreck the battery if its not checked on. Its best just to use them during long storage periods to prevent freezing and sulfation.

No, I have a Minn Kota 12 volt Terrova 55 pound with I pilot.

Here's another vote to re-examine your charging methods and tools. Once I started using this type of product to charge and maintain my batteries the life span increased dramatically.

In your case, hook it up now and leave it there till open water fishing starts again.

http://optimate1.com/product/optimate-7-select/

http://www.batteryminders.com/batte...2-4-8-amp-charger-maintainer-desulfator/

+1 on the battery minders. Used them for years and they work..they are a quality product.. I have some of the small units that are well over 10 years old

I assume then that you mean that you have 3 12V batteries in parallel, not in series.

I've heard good reports about Walmarts Ever Start's. I don't know who makes them.