Installing a trolling motor on a 21ft CC

[bruceb58]

How did you get 200 amps with 3 50 amp batteries ?

In addition to your confusion of capacity vs current. most small 50AH batteries will likely only be able to put out 50A so 3 of them will put out 150A max wired in parallel.

 

[airshot]

Using the max draw each use will shorten the life of these batteries. While they can handle the deep discharge, it will reduce the number of cycles the battery is able to provide. Also questioning why you will be needing to run your trolling motor at wot all the time ? The total runtime can be tripled or quadrupled by running your trolling motor at 50% as most guys do and that will also extend the life of that trolling motor as well.

 

[airshot]

Charling is something I've yet to fully get into as the mounting location will determine how I do it. If I go stern I'll get a charger that can do both AGM and Li batteries so I can have one cord but if up front likely two chargers since I suspect my trolling motor won't burn down that much battery very often. 90% of my fishing trips I'd run it less than 4 hours and based on what I found, the dual battery setup should give me 10 hours or so

You can still use one cord, just have multiple plugs on it. My boat gas three chargers and one cord.....the cord has a triple female plug on one end to plug the chargers into...

 

[SkaterRace]

Using the max draw each use will shorten the life of these batteries. While they can handle the deep discharge, it will reduce the number of cycles the battery is able to provide. Also questioning why you will be needing to run your trolling motor at wot all the time ? The total runtime can be tripled or quadrupled by running your trolling motor at 50% as most guys do and that will also extend the life of that trolling motor as well.

I presume that the majority of it will be the trolling motor determining the amount needed as per the current/wind for GPS lock and following tracks. I was using 100% as that's a worst case. I'd love to know I have enough for 80%+ of my trips with worst case in mind. It's also a nice to know in terms of "engine crapped out I need to make it to some shore"

 

[bruceb58]

Using the max draw each use will shorten the life of these batteries. While they can handle the deep discharge, it will reduce the number of cycles the battery is able to provide. Also questioning why you will be needing to run your trolling motor at wot all the time ? The total runtime can be tripled or quadrupled by running your trolling motor at 50% as most guys do and that will also extend the life of that trolling motor as well.

Depends on the specs for the cells although most are spec'd at 1C or 0.5C . Most of the time, it's the BMS itself that limits the current and the cells are capable of more.

These 50AH cells are actually rated at 3C https://www.evlithium.com/hot-lithium-battery/945.html

As far as the number of cycles go, most cells are rated between 3,000 and 5,000 cycles and I kinda doubt most people would ever see anywhere close to those numbers in their lifetime so that is a pretty moot point.