Dual Purpose Batteries

[TroutnMuskieHunter]

My son posted this on another site and got 0 replies....I told him to join a good site and in the mean time I'd post it on the good site I was referring to.. .....

 

Thanks....

Steve

 

I started having some issues with my main battery last year and I'm looking for some advice. I've recently upgraded the main sonar unit to an HDS-7 and after a long day on the water without running the motor a lot I can drain my cranking battery. Not sure if it was the sonar upgrade or maybe just time for a new battery but either way, limping back to the launch with the bow mount sucks. The current battery came with the boat, it's the largest Interstate marine cranking battery with 1000mca but it's at least 3 years old and I know I've discharged it more than a few times. I just ordered a new 3 bank charger to make sure I keep a good charge on the main battery this year but I'm pretty sure I'm going to need to replace the current battery.

What I'm wondering is if I'll be better off with a dual-purpose cranking/deep cycle for the main battery? I've heard some mixed reviews on dual purpose batteries and just wondering if any of you guys are running these. Right now I'm looking at the Optima D31M which puts out 1125 mca and has 155 min RC. The other option would be to put in a third deep cycle just for electronics and just replace the main battery with another cranking battery. I'd really like to avoid having 4 batteries if possible so the dual purpose is looking pretty appealing. Any thoughts?

[fish_fishburn]

Personally I would stick to a cranking battery for your motor. Maybe you should charge up the battery you are having problems with and then have it load tested. Just take it with you to wally world and they will load test it for you. If it needs to be replaced buy a Energizer marine starter battery and your problems will be over. The onboard charger you are buying will maintain your batteries alot better and you will get longer life out of them. I haven't had any luck with Interstate batteries, so I no longer buy them. The most I ever got out of them was maybe 3 yrs. There is also a product you can buy from a battery shop that you add to the cells and it rejuvenates the cells, I can't remember the name of it but it comes in a small plastic bottle with 6 increments on the side of the bottle. So much for each cell. I add this to my batteries every two years and my batteries last on average 5 to 8 yrs. Its about 25 bucks per bottle. If i'm not mistaken electronics don't draw that much power to draw a big battery down in less than a day on the water. Hope this helps.

[ssminnow]

I use the energizer dual purpose for starting, downriggers and electronics and have never had a problem. I have a power pack just in case but have never had to use it. I think this will be the fourth season on the energizer. The energizer are relatively cheap and so far so good.

[Roy]

Steve, your son will have no problem at all using a deepcycle as a starting battery. They're especially more efficient if he's running electronics off of one. The problem in the past was that the older motors needed more cranking amps to start...it's no longer the case. I'm still using two deepcycles for the bowmount and a starting battery for the main motor but that may change because my main sonar/gps unit is 8,000 watts peak to peak.

 

Tell him to keep a set of jumper cables onboard to power up his main motor from the bowmount battery if he ever gets stuck.

[JPD]

You're main concern will be with Reserve Capacity. MCA's past 800 are really only needed for the big 3.0 liter Opti's. Try to find something with 180 plus minutes of reserve for piece of mind. 3 Years for any battery, if used often is a good length of time, all of mine are replaced every 2 years.

 

JP

[TroutnMuskieHunter]

A little over an hour from me posting this and I get all these great replies...thanks a lot guys. I sent my son the link to this topic..this is what OFC is all about!!

[Fisherman]

One final addition, don't squander your money on Optimas, you can get 2 regular name brand deep cycle of the same size for pretty much the same price and have better output.

[skeeter]

when your starting battery goes dead why wouldnt you just pull start the motor, if its an outboard?

 

or even switch over batteries to the trolling motor battery?

[Whitespinnerbait]

Hey Trevor..

 

Let me know if you go with an Interstate Battery.....I can get you a Serious Discount on one...

[moemoe]

I had to replace my starting battery as well, I ended up getting a motomaster eliminator, I am sick of burning through "marine batteries", I picked up a group 65 with 160 minutes of reserve capactiy and 850 cold cranking amps, for around 120 bucks at CT, I had some gift certificates and crappy tire money, so it only ended csoting around 30 bucks, we''ll see how it goes.

Edited April 7, 2010 by moemoe

[scugpg]

One final addition, don't squander your money on Optimas, you can get 2 regular name brand deep cycle of the same size for pretty much the same price and have better output.

 

I really enjoy my Optimas and would recommend them to anyone. Light, easy to handle and plenty of power. You just need to charge them properly with a quality charger!

[Fisherman]

I really enjoy my Optimas and would recommend them to anyone. Light, easy to handle and plenty of power. You just need to charge them properly with a quality charger!

Well glad you're enjoying them, but I'll stick to my guns and say that it's a marketing ploy. Take a Blue Optima Gp 31 only rated at 155 minutes reserve capacity, well over $200 and copmpare it to a standard Gp 31 battery with 205 minutes reserve capacity for $139. Thats a 25% increase in power for a whole lot less money.

[Jackie]

Your Lowrance has a GPS and its antenna draws a lot of power. I had that same problem many times before. My Lowrance is wired to my starting battery, while my trolling motor to the deep cycle. After fishing a couple of hours or so with my trolling motor, with my GPS/fishfinder on, I would have drained both my batteries, and I'm dead on the water. My solution is to wire everything thru a battery switch. I would use my deep cycle for everything: cranking, trolling motor and electronics. The startup battery will be untouched. This way everytime when I start my motor, it will recharge the deep cycle. In the worst case if I really drain it, I still have the startup as my backup to get back to shore. And I can still fish as long as I don't use the trolling motor or electronics when the main motor is off.

 

I was quite surprised by the current draw of the Lowrance unit I have. Another way to get around this is to have a separate switchable circuit for the GPS antenna (mine has external antenna), so that when you're not moving, you can turn it off. But then re-obtaining the GPS coordinates will take a long time for cold starts.

[ecmilley]

I have been using the die-hard line of batterys, i use the dual purpose 24 series to crank and run my electronics, I believe it's only 140 mins reserve but i havn't had any problems with draining the battery yet even when spending 5-6 hours casting still starts the evinrude 150hp good and i run the hds-8 as well as a hummingbird colour unit on the front.

But i also keep some boostercables in the boat just in case, i figure it's not a matter of if but a matter of when i'll be left with a dead battery.

Also check your water levels and keep all your batterys charged I plug in after every trip on the water and can knock on wood to no problems.

the diehard line is distributed by east penn battery who also distributes the powersurge and bps line of batterys

[XXXL]

Thanks for all the great replies guys! The new Minn Kota 3 bank charger showed up yesterday and I got it installed. Once the cranking battery has a full charge I'll pull it out and get it tested.

 

Still not 100% sure on what I'll do if I need to replace it. The cost of just replacing it with another cranking battery seems nice but if I'm constantly draining it with the electronics I'm sure I'll be replacing it again sooner than later. On the other hand I can get a decent cranking battery for around $100 and I could replace it 3 times for the cost of the Optima D31.

 

I'm using it to crank a 115 Opti (this is why I didn't pull start it) and the manual says it needs a minimum of 1000mca. It seems to be more picky about voltage than the mca. Last year when it died on me the motor was cranking but I got no beep when I turned the ignition on so I assume that the computer wasn't seeing a high enough voltage. I put a meter on it when I got home that day and it was still reading over 12v.

 

To me it seems like this would be the intended use for a dual purpose battery but from what I've read a lot of folks say they do a decent job as a cranking and/or deep cycle but they're not really great at either. Guess I'll wait to see how the current battery tests and then make a decision. Based on the replies here, and the $$ I'll probably just go with another cranking battery and see how long it lasts.

 

One thing is for sure... I'll definitely have a set of booster cables on board this year! Anyone know if there are any issues with boosting from a single battery that is wired in series with another? I know I only use the single battery to get 12v but should I remove the cable between the 2 batteries that are in series before I boost?

 

Thanks for the offer Paul. I may take you up on it. We can talk when I pick up those Northam's from ya.

 

Cheers

[Fisherman]

One thing is for sure... I'll definitely have a set of booster cables on board this year! Anyone know if there are any issues with boosting from a single battery that is wired in series with another? I know I only use the single battery to get 12v but should I remove the cable between the 2 batteries that are in series before I boost?

Cheers

You will have no problem getting a 12V boost that way, only using the + and - posts from one good battery. No need to remove the cables.

[Whitespinnerbait]

Thanks for the offer Paul. I may take you up on it. We can talk when I pick up those Northam's from ya.

 

Cheers

 

 

I'll be throwing on some Free Muskie Lures soon ....Wonder if your Dad will take a stab at them

 

 

 

[TroutnMuskieHunter]

I'll be throwing on some Free Muskie Lures soon ....Wonder if your Dad will take a stab at them

 

 

 

 

Don't waste your time as I'm NOT interested.....give them to your nephew