Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Results 1 to 5 of 5
  1. #1
    Join Date
    Feb 2004
    St Louis

    Default How to connect two trolling batteries together.

    I just bought another deep cycle battery for my trolling (12V) motor, I was wondering how to connect both batteries together so I get more trolling time (not more volts.2. Question two I have a three bank onboard charger for my batteries that I also just bought.If I was to connect my batteries together how would I connect the charger to it ? - Would I connect the leads to on deep cyclebattery to charger both of them ? - Would I put a lead to each of the two batteries ?Any help would be greatly appreciated guys..Here is the charger that I bought:XPS 5/5/5you can see it here: Web site for Battery Charger

  2. #2
    Join Date
    Aug 2003

    Default Re: How to connect two trolling batteries together.

    I would suggest some kind of switch that will just allow you to switch from one battery to the other when the first one is dead. It's not a good idea to wire a new battery in parallel with an old one, especially if they are a different brand/capacity.

  3. #3
    Moderator JB's Avatar
    Join Date
    Mar 2001
    The Hideout, Whitt, TX, USA

    Default Re: How to connect two trolling batteries together.

  4. #4
    Petty Officer 2nd Class SingleShot's Avatar
    Join Date
    Jun 2003
    Racine, Wi

    Default Re: How to connect two trolling batteries together.

    I have the same setup although at I only have a dual bank charger as I wasn't thinking clear when I purchased it a year ago. I added a blue sea battery switch. This allows you to switch between bat1 bat2 both or off. I put inline breakers in front of each battery. The switch requires just 3 leads bat1 pos bat2 pos and the switched output, which you just connect to your trolling motor connection. As for your charger you would connect direct to the batteries. Connect out1 to batt1 pos and neg, then do the same for bat2 and bat3. Now bat1 and bat2 will have to have a jumper connected across both the neg terminals rated or sized to what you have already. This may seem strange as the the neg leads from the battery charger could be connected to one of the two but I wouldn't. So in short you will have 2 neg connections to one of the batteries, 3 neg connections to the other battery. The extra connecton is the system ground of the trolling motor. Use the battery switch to select 1 or 2. I personlly do not use both as if you have one battery going bad it will take the other one with it "as previously stated by the above post". When charging select off to disconnect the trolling motor, this way you do not have to unplug it as charging batteries with the trolling motor connected can in some cases damage the trolling motor. If you do not connect the 3 output to your starting battery make sure you connect it to one of the deep cycle batteries. I beleive the XPS is similar to the mariner pro and uses distributive charging. That is you have 15 amps total, so as one battery is returning to 100% the avalible current will be used on the other outputs. I hope I didn't confuse you. Good luckSingleShot

  5. #5
    Seaman Apprentice
    Join Date
    Sep 2001
    anderson, sc

    Default Re: How to connect two trolling batteries together.

    I an no battery expert but I believe you can wire them together. A fishing buddy of mine has a boat with a 12v tm and he told me he wired them together. It is a little different than wiring them in a series for 24 volt but am not sure what.Go to and there are several threads there on this situation.

Similar Threads

  1. Would my old Trolling Batteries be ok to use?
    By jammer in forum Electrical, Electronics, Audio and Trolling Motors
    Replies: 8
    Last Post: July 30th, 2007, 04:11 AM
  2. Trolling motor batteries
    By 2 lund bums in forum Electrical, Electronics, Audio and Trolling Motors
    Replies: 4
    Last Post: May 2nd, 2007, 03:20 PM
  3. Splice 6" leads to connect trolling receptacle with smaller wire?
    By retrorocket in forum Electrical, Electronics, Audio and Trolling Motors
    Replies: 9
    Last Post: March 22nd, 2006, 02:13 AM
  4. Trolling Motor Batteries
    By DJ in forum Non-Repair Outboard Discussions
    Replies: 3
    Last Post: March 2nd, 2003, 07:05 AM
  5. Trolling motor batteries
    By Gadgetman in forum Boat Topics and Questions (not engine topics)
    Replies: 0
    Last Post: February 8th, 2003, 05:08 PM
  1. iboats Forum Directory - Over 100,000 forum posts organized by topic