Install a 2nd battery or have a jump starter pack?

[arminius]

I have a 19' deck boat, and it has one good battery. However, it was recently dead after I didn't use it for awhile. So I had to pull it out, and charge it, blah, blah, blah. The worse thing would it being dead while on the water. I'm wondering if I should get a 2nd battery and install a two battery system? Or the other option which seems logical is get a jump starter pack https://www.westmarine.com/buy/west-marine--700-amp-jump-starter--15808504?recordNum=1 and have it handy when using the boat? Thoughts?

 

[BRICH1260]

I`d install a second battery, even if you just do a simple parallel wiring system between the two. The best option would be to add the second battery and separate them via an A/B switch.

 

[southkogs]

If it was dead from under-use, why wouldn't that happen to the second battery as well?

Not that I'm against a two battery setup. Just suggesting that from your post you have the potential for a two dead battery setup.

 

[PondTunes]

Having two batteries wired in parallel is exactly the same as having one much larger battery, in this case two dead batteries which you will likely need to disconnect to charge.

Also you run the risk of if one battery goes bad say with an internal shirt it could kill the spare battery as well.

If you go dual batteries use a 1/2/off/both switch if you don't mind remembering to flip the switch when needed. Ie 1 for cranking, 2 for accessory use when sitting or both when underway charging. The problem with this setup is when installed and you're not used to flipping switches you will eventually leave it in the both setting thinking you have a backup battery and again be left with two dead batteries.

My preferred method of doing dual battery setups is using a "smart" relay which can tell when the engine is running, it will automatically charge the six battery when the starting battery is full and the engine is running. Blue sea systems makes a nice kit for this that last time I checked was about $140 you hook up your engine to a starting system and your accessories to the start battery and forget about it. There is a combine option if your starting battery had an issue that it needed a boost to get your engine started.

The only problem with carrying a jump pack is if for some reason you never charge it or use it and it fails. Then you're just as stuck with any other option!

 

[Silvertip]

It doesn't matter what system you use if "under-use" is the issue. Leaving lights on, a bilge pump running, radio left on, etc., any of those will kill a battery. Even the radio when turned off has a "memory" feature that draws power. Granted it takes weeks for that to happen but that all depends on what under use in your case is. Two batteries will not solve an under-use situation as was pointed out. For best battery life you need to keep batteries charged while NOT used. Charging them just before you head out does not make for long battery life.

 

[82rude]

I have one of these which goes with me everywheres.If its not in the boat ,its in the truck or on the atv.Its one of those things that you hope you never use but is real handy when needed by you or maybe somebody else you can help.You can see its easly checked for charge and will hold for a very long time.http://www.batterymart.com/p-gb40-b...p-start.html?gclid=COOvwti64tMCFdu1wAod0ZMB7g

 

[oldjeep]

Second battery with an a/b switch and a dual bank smart charger is my setup. The dual batteries are piece of mind and the charger keeps them in top shape when it is in the garage.

 

[dingbat]

if I had a dollar for every jump box someone pulled out of their trunk to "save the day" that was too under charged to work or dead, I could have retired by now.

 

[JASinIL2006]

When I got my boat, it had a single battery. I bought a second battery as a backup; it wasn't connected to anything and had to be manually charged every so often to top it off. That got old fast, so I decided to add the second battery properly and separate starting and other electrical needs. Lights, radio, GPS/depth finder are now on the second battery, while the first is dedicated to starting (and a backup bilge pump).

I thought about connecting the batteries using a simple Off-1-2-Both Perko switch (as described in the article link you provided), but it sounded like it would be pretty easy to accidentally discharge from both batteries by forgetting to change the switch.

Although it's a bit more expensive, I decided to go with a Blue Sea Add-a-Battery kit (http://www.iboats.com/Add-A-Battery...2066984--session_id.082095076--view_id.730150). It provides great peace of mind; I can now run electronic equipment off the house battery and save the starting battery. The house battery also serves as a backup in case the starting battery fails.

The nice thing about the Blue Sea kit is that you basically set it and forget it; the batteries are separated for purposes of discharging (so you won't drain your starting battery because the radio was left on, for example), unless you override it and combine them. When the engine is running and the alternator is generating electricity, power will be sent to whichever battery needs it, without have to set any switches manually. It couldn't be easier.

If you do add a second battery, be sure to get proper cabling. There are a number of companies that sell custom made cables using tinned copper wire (to resist corrosion) with whatever sorts of terminal connectors you want. They aren't any more expensive than buying wire yourself and trying to crimp on connectors. You can specify exactly what you need and have them delivered within a few days. It makes the job much easier.

Good luck!

 

[Alumarine]

I always carry a battery pack that I check regularly to make sure it's charged.
I've never needed it for my boats but have used it on other peoples boats as well as my truck once.
I also have a cheap set of jumper cables on board.

 

[drrpm]

If the battery is good enough to start the engine when you put in you should be alright for the day as it will charge while you run the boat. Its probably worth pulling the battery and having it tested to make sure its not about to die. Another thing to check is the cables and terminals since they may corrode and lead to a poor connection.