battery question

Is it possible to hook 2 deepcycle batteries together and still keep it 12 volt?

Yes….you hook them parallel + to + and – to – = 12 volts.

You will need to make up a jumper cable. You can expect powerfull results, you may get as much as double the cranking amps and reserve capacity. And yet remain at 12 volts.

Right Bobber, if you hook posative to negative on both batteries you’ll get 24 volts. hook the posative from one battery to the posative on the other. do the same with the negative posts too then run two cables or wires from the posative and negative post from one battery, for whatever your service demands are, trolling motor or starter for your engine. I’ve got two batteries wired like this for my engine starter via a set of good jumper cables without the clamp ends. i soldered together the posative cable from my starter motor to the posative cable from the battery and the same with the negative, put both in two heavy duty battery clamps then greased them good to keep oxidation off the clamps. The same can be done for trolling motors too but you’ll need 4 gauge wire or bigger for less resistance in the wires if your batteries are over 4′ apart. a cheaper set of jumper cables, minus the clamps will work for this purpose too. There isn’t any tow trucks out on the water that i know of.

I would not recommend hooking batteries in parallel – as any cell in one of the batteries gets weaker (or goes bad) it will suck the life out of the good battery and generate a lot of heat keeping both batteries at the same voltage. This could be a dangerous situation and will destroy the good battery along with the battery that is going bad.

It you are going to do this anyway, then make sure all batteries to be hooked in parallel are the exact same capacity and bought at the same time.

Dave Gulczinski

Right dave, when i change batteries i buy two of the same amperage. I used to run interstates because i’ve never had any problems with them. Now i run two 940 amp batteries from wall mart because of thier no hassel return when i want to change them. I use them for two years then return them and pay the diffrence on the pro rated price to keep fresh batteries in my boat. The wall mart batteries seem to be good batteries with never haveing a problem with those eigther. Can run my fog, spot, aireator in live well, bilge if necessary, bow and stern lights all night plus start my 40 horse merc. motor all night when checking lines and theres enough power left to get me to my trailer. A guys gotta have fresh batteries.

I have posted a few times about taking two 6 volt Marine 240 amp interstate batteries and tying them together to make a 12 volt system. Run a heavy 4 gadge wire pos one battery to neg the next battery. Then I like to run a heavy stranded wire off the pos end of one of the batteries to a terminal block of which I use for all of the accessories. Use the neg side of the other battery for and run a heavy stranded wire off the neg end to the other neg terminal block. The advantages are obvious. The batteries are good for atleast 6 yrs. only cost about $70 a piece. and last about twice as long as the two 12 volt batteries out on the water. The terminal block wiring harness will take you about 2 hrs and that’s the only draw back. {John}

My two cents….

With the Interstate brand of batteries. “Hassle”. I’ve called and emailed their 800 and two local dealers. Interstates “warrenty” email address was returned to me undeliverable. I sent that whole email to the “customer service” dept. over a month ago….no response. After speaking to one local dealer, they said they didn’t have an answer for me and would call me back…three weeks later, I’m still waiting for that call. One dealer call me back, said the I should drop the battery off, then when the Interstate rep comes around, he will decide if it’s under warrenty and he would know the cost.
My question to the above was “do you have the 24HD in stock and what would the prorated cost be after 18 months”.

I’m going to Wal Mart this spring for a no hassle battery.
Maybe I’m just the lucky one as this was my first experiance with Interstate.

ONE word of caution! If you are planning on using two batteries, make sure you are THINKING when you connect them together. Red+ to Red+ and Neg- to Neg- for the same voltage as one battery.
If you connect Red to Black and Red to Black, you will receive 24volts of sparks welding the connections to the battery….if your luck, you will just ruin two batteries….if your not lucky….don’t want to think about that!

Remember with series connections two terminals will be free to connect what ever you are planning on running. One Red and one Black.

Also, at any auto parts store, you can buy a black and red two or three foot cable with “post” connection and on “eye” connection on the other end. These are made for battery connections. They run about 8 to 9 dollars.

If you have a doubt in your mind about connecting two batteries together, email or pm myself or anyone of the above for more details. I like the safe than sorry thought!

thanks guys