Trolling motor

[Cadillac]

I have some experience with battery packs and building packs. Samsung 18650 are at the top for performance. I have Golfboard’s at work that we rent that are 50 volt batteries with a 28.5 ah charge. I’ve had to disassembly the battery packs to find faults. Packs are 100 18650 batteries wired in series and parrallel all monitored by a bms. Problem with packs is one battery goes bad the bms senses a problem and stops charging. So one bad battery gotta but a new one at 1200 bucks.
I’ve taken the packs apart and built myself all types of battery packs and charge off a charger used for RC cars that balances and charges up to a 6 bank battery cells. I’ve disassembled battery packs from my portable tools that don’t work anymore. Found one bad cell and replaced with a 18650 battery from my packs. Tool batteries are still working fine 2yrs later.
My son has a JD power wheel that I built a 16v pack for. 10 18650 in series then 4 row in parrallel. Son has the fastest power wheel in the neighborhood and last about a month on a charge. I just built him 24v packs for a razor dirt bike we got him they are awesome.
Lithium packs vs. ni-cad is night and day difference. First the power is more,faster charge, and lighter. Lithium does not like water and will explode, they are more temperamental than a ni-cad but the trade off is incomparable. If you interested in the lithium batteries I have 48v packs that may have one bad cell in it that I’d get rid of I have about 10 of these packs. Just for a reference one 18650 Samsung battery cost about 4-6 dollars a pc.
I’ve seen people make battery bank walls for solar power where they have a shed filled with these 18650 batteries pretty amazing stuff. Here’s some pics of the pack I disassembled and some of the ones I’ve made.

 

[MikeInOr]

Our neighbor has a fishing kayak that is pedal powered. It leaves his hands free for fishing. It is quite seaworthy and he has taken it into the Gulf of Mexico and the Gulf of Alaska.

I believe you are referring to the Hobie "Mirage" drive kayaks. Very cool and efficient pedal powered kayaks... but expensive!

 

[westerner]

Amp/hours, distaste for water, one cell dies and the whole pack is dead, etc, etc,etc. I would go lead/acid, "Trolling/Deep cycle", and keep my paddle handy. That said, my kids call me a "fossil"

 

[Cadillac STS]

You can get an Optima deep cycle battery that is small. Like half size of a car battery. You want deep cycle so you can bleed it all the way down and recharge it without damage. And they can be mounted in any orientation like maybe on its side in the kayak.

Relatively costly but could be an item you buy once for years of reliable use.

 

[RJSakowski]

...........any better options what say you ?.

An 85 amp-hr deep cycle battery has about 1 kw-hr of energy stored. The Panasonic 18650 Lion cells used by Tesla weigh about .1 lb. each and store 12.3 w-hrs of energy. A good target would be 500 w-hrs. 40 cells configured as 10 banks of 4 cells in series would provide 492 w-hrs of energy storage @ 14.4 volts and weigh in at about 4 lbs. Add to that a housing, controls, and safety equipment and you're probably around 6- 7 lbs.

 

[Chris John]

This is something useful I found that might help Trolling Motors

 

[Hawkeye]

Google Bixpy. I have one of these. I haven't tried it on any of my kayaks, but it really works on my long-boat. Motor and battery are around 9 pounds. Full power: 75 minutes; lowest trolling speed: 10 hours. They have quite a variety of mounts available.