Thread: Another battery situation

Running a fish finder off a trolling motor or deep cycle battery is not recommended. Fishfinders do not do well with low voltage or voltage drops.

I would suggest you add a small lithium battery. Some people run their units off drill/tool batteries or you can buy a compact battery like Amped Outdoors that is light weight. A 15 to 24 amp hour would be plenty.

Charge the battery and take it to wherever you buy batteries and they will test for free, bet your battery is bad. We run off a group 31 deep cycle for years, but now with 3 fish finders up front one on the console and a livescope we have added a couple dewalt batteries simply for the low weight and added amp hours. The only issue you may encounter would be interference from the trolling motor and that would likely require separate batteries

Never run your electronics off the TM battery. Also a hot cable is an indication of a bad connection or cable.

Ok thanks all. I think I am understanding the problem now and have new questions. Does anybody use motorcycle batteries? When using a lithium how do you mount it? USGC requirements?

Sent from my SM-G960U using Crappie.com Fishing mobile app

Your garmin is using what? No more than a couple amps? Motorcycle batteries can be fairly high dollar. Check out amped. You can use lithiums laying on their side, upright, even upside down, as well as stacked. Call them and chat with them and see when they get their 18v in.

LiFePO4 Batteries 12V Affordable Lithium Battery | Energized Outdoors | Amped Outdoors

How do you re-charge the lithiums?

You'll need a special charger for lithiums.

Personally I would probably just upgrade to a group 27 or 29 deep cycle. Should give you plenty of juice, and you are not looking at a huge weight consequence compared to what you already have.

You can run your graph off of the same battery, although you might get minor interference. If anything I prefer it that way, since you get a real time voltage reading from the graph, makes it easy to monitor how much battery you have left.

Drill batteries and stuff will work, but I'm a fan of simplicity, I know if I had them, eventually I would leave them at home, or forget to take them out and charge. I like for my boat to be rigged and ready, hook up and go.

Most chargers that have a agm setting to charge agm batteries will charge a lithium battery. You can also check with the place you buy lithiums to see if a battery charger that has a agm setting is compatible with the lithium battery you buy. Amped has some real inexpensive lithium chargers also. Check their website for prices.