Thread: Battleborn lithium battery: Melted trolling motor wires

Originally Posted by Traveling Man

Properly sized overload protective devices will prevent this issue.

Not necessarily. A protective devise (breaker) will trip when the wire is trying to carry more current than the breaker size (in this case, 60A). That does not appear to be the case here. This appears to be a case of the components not being designed robustly enough to carry a 60A continuous load. If BigD had had a meter to watch while using the TM, chances are it wouldn't have been pegging at even 60A. Minn Kota (and other manufacturers) simply size wire and connections for something less than continuous full load.

I don't know which model of the Wireless Motorguide xi3 that you have, but just looking at the 70lb model, that one comes with "Digital Power Management for up to 5x longer battery life", according to their site. One would think that power management program would address such an issue as you encountered. I would discuss this with the manufacturer, this issue *might* be warranty covered, especially if in your paperwork you cannot find it DOCUMENTED to NOT use lithium batteries.
BTW - Have you seen on the motor what the max amp load rating is for the motor? I would assume that it would be for less than the 60 amp rating listed on the Minkota Power Center Built In Breaker, that incidentally I think should have "Kicked Out".
I just keep thinking that this whole deal should not have happened. That's an expensive trolling motor that in addition to performance, it should have also provided PROTECTION. In no way does that melted wire suffice as a fusible link!
Not to imply that I have fleas, but I would "Bark" at Motorguide a little more, and perhaps they will get tired of the barking dog and toss you a treat!

Originally Posted by TheGrandPoohBah

I don't know which model of the Wireless Motorguide xi3 that you have, but just looking at the 70lb model, that one comes with "Digital Power Management for up to 5x longer battery life", according to their site. One would think that power management program would address such an issue as you encountered. I would discuss this with the manufacturer, this issue *might* be warranty covered, especially if in your paperwork you cannot find it DOCUMENTED to NOT use lithium batteries.
BTW - Have you seen on the motor what the max amp load rating is for the motor? I would assume that it would be for less than the 60 amp rating listed on the Minkota Power Center Built In Breaker, that incidentally I think should have "Kicked Out".
I just keep thinking that this whole deal should not have happened. That's an expensive trolling motor that in addition to performance, it should have also provided PROTECTION. In no way does that melted wire suffice as a fusible link!
Not to imply that I have fleas, but I would "Bark" at Motorguide a little more, and perhaps they will get tired of the barking dog and toss you a treat!

Thanks GrandPoohBah.

Well I have given the motor and battery 40 hours on the water test since this instance.
I now have a 50amp breaker and a 2 foot 4 gauge wire from breaker to battery.

I tighten each fitting before going out.
The longest I have trolled is 12 hours over 11 miles in a day.

6 of those miles was at 80 percent thrust.
The wires are checked every 10 minutes to see if they get hot.

The only time I had any heat (hot to the touch) was when the terminal fitting on the hot side loosened from boat bouncing.
Once I retightened the wingnut on the terminal, the heat stopped and all is well.

It appears that tight fittings and slower than maximum speed is the ticket with lithium batteries. Tight fittings probably on all batteries.. Dah!

Hopefully the manufactures of trolling and marine batteries can work together to insure safety of motor and battery at full speed.
New technology has worlds colliding...lol

When you buy a new marine battery the first thing you do is take those wing nuts off and throw them away. They are notorious for working loose and causing problems. Use an ordinary hex nut.

Originally Posted by BigD

The only time I had any heat (hot to the touch) was when the terminal fitting on the hot side loosened from boat bouncing.
Once I retightened the wingnut on the terminal, the heat stopped and all is well.

Sounds like that nut would benefit from a generous dose of Blue Loctite.

You could always use a second hex nut to lock the nuts together. They make jam nuts for that purpose. It would them be locked together mechanically instead of with loctite. With my luck I would damage the battery post before the loctite released

Don't use wing nuts on your battery posts, they will work loose and burn up your wiring when under a heavy load.

Snug fitting Star Washers will take care of that issue for you, either way with the wing nuts or if you go with others.
If you remain with the wing nuts and go star washers, put a dab more tighten on 'em with some pliers and leave those pliers in the boat with you in case you ever needed to remove them. Now would also be a good time to consider a disconnect switch at the battery. A simple blade type would do fine. Easy to disconnect power when not in service, fast and easy to disconnect if you ever have a problem out on the water. Amazon.com