Trolling motor batteries

[Ole fisherman]

My Wal-Mart starting battery is going on 7 years now with no signs of weakening. The house battery was replaced last season at 6 years of age. Trolling batteries (2) were replaced this spring ( 6 yrs) with one 140 ah lifep04 battery ant it runs almost twice as long as the two agm batteries from walmart.

[gb1234]

Update on my battery experience...
1. It took exactly 2 weeks since I emailed Li Time Support until I received a replacement battery.
2. I asked them what can be done to prevent the internal cells from becoming unbalanced and they claimed the BMS would do that. That's not true because the BMS didn't do it for the battery I returned - unless the replacement battery has an updated BMS.
3. Interestingly, I see that Li Time now offers a "TM" version of their 100 Ah LiFePO4 battery. (TM stands for Trolling Motor). It has the same specs as my battery, except its BMS allows a greater amperage pull for a short time. This tells me the start up of an 80lbs Minn Kota probably tries to draw more current than a standard BMS will allow.
So, if I had to do it all over again, I would buy a battery that allows these short-term higher draws. I would really like one with Active Balancing, but no one advertises that feature at this point.

[Ole fisherman]

My guess is you jyst got a bad one....no matter who, a bad one can show up on ocassion. When I bought my look from TimeUSB, I called them, discussed exactly what I wanted to do with my particular trolling motor and how much power I wanted from a battery. They recommended the battery and charger, which I bought. No problems and I am amazed at how well it works. Let us know how this new one works out...

[gb1234]

First trip with the replacement Li Time battery today...
I think it did fine. It lasted about 6 hours, but I had the Minn Kota running between 7 and 10 the whole time - because it got pretty windy and I was trolling into it. I would like to compare charge time versus how it used to be, and whether one battery charges faster than the other. It used to take overnight to charge these guys back up with my little NOCO. However, the recommendations now are to store them at only half charge, so I won't get to see if the charging is the same as it was before. I assume it would be. Hopefully this new one lasts more than two seasons.

[gb1234]

The thing I'm struggling with is that I have just a little 16' aluminum boat. It's not even a deep V. It's about as light as you can get, and not tall enough to catch much wind. I have an 80# thrust Minn Kota. Shouldn't that be more than enough power for my little boat?
It's not like I'm going out in gale force winds.
And yet spot-lock - even on the lee side of an island - is still taking it to 10 with LiFePO4s. And auto-pilot also takes it to 10 when trolling. Maybe my Minn Kota is bad?

[pfk]

The thing I'm struggling with is that I have just a little 16' aluminum boat. It's not even a deep V. It's about as light as you can get, and not tall enough to catch much wind. I have an 80# thrust Minn Kota. Shouldn't that be more than enough power for my little boat?
It's not like I'm going out in gale force winds.
And yet spot-lock - even on the lee side of an island - is still taking it to 10 with LiFePO4s. And auto-pilot also takes it to 10 when trolling. Maybe my Minn Kota is bad?

if your auto pilot takes you to speed 10 without you setting it on 10, there's a problem with your motor. get it to a certified service center and get it fixed right.

[gb1234]

That stinks because sometimes 8 isn't enough.
How does the MK know when to try again? Last time out with the Li Times, I reconnected after a couple hours but the MK still wouldn't turn on. But it came on right away with the MillerTechs. That made me think it was the Li Time BMS preventing operation and not the Minn Kota.