Second battery vs jumper box

[Senor Snagger]

My buddy is giving me grief that I only have 1 battery on board. I have no trolling motors. I have a fishfinder, vhf, 2 bilge pumps and a radio. I'm comfortable having a fully charged jumper box on board and he says I should parallel a second batter. Do I need a second battery if is tge jump box a sendible safe alternative?

[Frogger]

Some questions one might ask first, is your main motor an outboard that can pull start if needed? Do you troll with your main so that it's charging? Do you venture out in finger lakes or ontario? How often do you find yourself draining your battery now? Do you have a kicker motor? These might help you answer your own question. A second battery adds weight but can be truly needed based on above questions.

Sent from my iPhone using Lake Ontario United

[Senor Snagger]

Thanks for the response. Main motor for trolling. No kicker. Can be rope started(have a starter cord under the cover. I also bring out a 1700 peak amp jump starter box onboard at all times. I will troll ontario 4 times a year. Run the bays here in NJ, Thousand Islands twice a year.

[TileMan Dan]

I think you're more covered. I have a 2 battery system on my boat and like you I also keep a jumper on board at all times also

Sent from my iPhone using Lake Ontario United

[baitrigger]

Having the second battery is about piece of mind. It is not a jumper. Install a switch so you can go back and forth and you add life to both batteries. The second battery is money well spent. Imo

[Has Been]

If you parallel a second batter& they both run all the time, if you get a short or something else goes wrong ,it will kill both & you will have the same situation.Get a switch & follow the instructions on install.

 

What is also nice is at the end of the day, you can turn the switch to off & kill the power to the whole boat. I do this all the time on my big boat. Saved my bacon a few times as I have left something on        ( light or radio etc) that would have killed the battery when I showed up next morn.

 

Switch, battery, & cables probably around 200 bucks. On a bigger boat it should be standard equipment.

Edited December 24, 2014 by Has Been

[kayaker919]

I recommend one of these:

 

Blue Seas Add-A-Battery Kit - 120A PN 7650 or 765003

 

Mini Add-A-Battery Kit - 65A PN 7649 or 7649002

 

 

These kits allow you to:

1.  disconnect your batteries when not in use (except bilge pump of course)
2. isolate batteries from each other but provide automatic charging of both batteries when running your motor
3. combine batteries when in trouble.

 

I have the 120A unit in my boat.  I run all electronics and downriggers from one battery, the other battery is for starting.  Pretty much idiot proof.

I also use my main motor for trolling.  Both batteries are marine starting batteries.

[zipnzim]

West Marine good price on ADD-A-BATTERY 120A and free shipping