Just some food for thought here.....your old 17#  trolling motor will draw the same or more battery power than a newer 36# or higher motor.  Many improvements have been made over the years on reducing the battery draw on newer electric motors.  Today, everyone wants 55# or higher electric motors, so there are quite a few 36-45# thrust used motors out there that would actually use less battery power in the long run as long as you don't run wide open.  Yet you would have extra power if you really needed it.......again just some food for thought.....good luck...

A fair point. 
 

I was out yesterday and as always, for the most part I am running the motor at 1 or 2 most of the time. Coming back I did run it at 4 and I was surprised at how fast (relatively speaking lol) that I was moving. It was leaving a wake. Not big, but a wake is a wake!

 

What surprised me is that when I connected the charger, the battery was still between 60%-80% charged. The first two times I used the motor it was at 40%-60% charged. So I am very satisfied with the performance of the battery and a 38-40 year-old motor lol. 

Before anyone buys lithium batteries please read Cobalt Red by Siddharth Kara.

All lithium batteries cells are made in china, domestic lithium batteries only make battery cases for lithium cells.

Good technology that belongs made back where it was developed Here!

Tom

It’s been almost a year since I bought this battery, and being on the Gulf Coast of Texas, it does get used 12 months of the year. So far it has performed as well as can be. I’m still running that old Minn-Kota 17 lb. thrust motor that’s 40 years old now. Neither has let me down yet. All-in-all I’d say this battery was well worth the price paid. 

On 9/3/2024 at 12:54 PM, airshot said:

 so there are quite a few 36-45# thrust used motors out there that would actually use less battery power in the long run as long as you don't run wide open.  

 

This would depend on motor speed controls.

 

Something a lot of fishermen may not be aware of is a trick trolling motors throw on us.

 

It seems to make sense that in those lower powered motors, that using lower speeds would use less energy right, but what if I told you that is not always the case because of how they are designed?

 

This is a secret most are not told. It revolves around old speed control designs. Older lower end models do not have electronic speed control. They use wire wound resistors down inside the motor.

 

 

And you can see from the shape of it, it is designed to be inside the motor housing itself down in the water because they use the water to keep it cool.

 

When you switch to slower speeds, excess battery energy is burned off in the speed coil resistors inside the motor. This is wasted battery energy doing nothing but turning into heat and not being used by the motor in any way. Its a trick!

 

So back in mid 1980's Minn Kota contracted out to another company to build their first electronic speed controller. With this device we cut out all the heat losing resistors wasting energy. Cut them completely out of the circuit.

 

Wire directly to motor brushes and take a look at what Minn Kota has to say once the above resistors are removed... also keep in mind what is shown here Minn Kota is comparing to the above but not quite outright saying it, only implying it. I have 3 of these and have been using them for decades. My 40 year old maximizers are still kicking in 2025!

 

I have talked to Minn Kota several times about this device seeking schematics and service info and Minn Kota says it was contracted out for only 2 or 3 years 1984-1986, and they have absolutely nothing on it today. We are on our own. These have not been made in 40 years, and are no longer available except to try and find a used one if you can.

 

I modify mine. I extend the speed control wiring so I can move from front to back of boat rather than the short 3 foot cable it comes with. I also sometimes change the speed control itself to a different taper which has a smoother startup and climb rate. The stock control seems to jump into action and I want a more slow take off. More variation at the slower speeds.

 

The nice thing about this device is I can perfectly dial in my speed. Switches only give you 3 to 5 specific speeds which may be too fast or too slow for conditions. This device adjusts speed perfectly anytime instantly. This same technology is common place today in all high end trolling motors. However, none of them have lasted 40 years like this one has.

 

If you read the article below it makes it clear that when you run the old style motor with speed coils, the battery is constantly draining. Not so with this device. It pulses to the motors. It is using less energy to do same work. Article says it can produce 20,000 pulses per second at full speed and it slows the pulses widening gap between them to slow motor down. Draws less. Uses less.

 

But just take a look at how much the efficiency increases once those heat resistors are cut out. From hours of use to DAYS ad says!

 

Point is, going slow with the old switch-a-roo design and heat resistors does not really save energy.

 

Most do not realize this big old resistor coil in the motor is glowing darn near red hot while you are trolling slowly above not knowing it or even thinking about it while believing you are saving energy with battery on slower speeds. It also is burning up the contacts in the switch as well which begins to slowly melt the plastic housing leading to failure of switch too. Wasted heat energy everywhere! All wasted energy. You can go around this situation very easily.

 

What this old 1980's ad shows is how to do it. I've been doing it like this for decades, but sssshhhhh don't tell anyone the secret.

 

In the first column of description from ad below it says and I quote: "Rheostats slowed motors by burning current in heat" and there it is. Open declaration. Slow speeds on old lower powered motors simply burns off excess energy as heat in the resistor coils inside the motor. It does not save energy and this ad says so! And even provides the solution. Which it does! For 12 volts only that is and motors up to 55lb thrust. I gotta go elsewhere for 24v and 36v.

 

With this device, I can troll for days on one battery charge no problem. It says 3 days here. I never went THAT far. Maybe 8 hours. No issues. Fantastic device! Has not been made in 40 years! Love these!

 

When you use this device virtually all battery energy is used for thrust, and none wasted as excess heat. Well almost none. "Fish DAYS instead of HOURS before recharging!" Where do you think Minn Kota is suggesting all that wasted battery power is going to? Only one place. Resistors hidden inside the motors.

 

Just think about what Minn Kota is telling all of us here. They are saying the difference is just hours on speed coils wasting energy as heat compared to 3 days trolling around on one charge. They are saying the speed coils burn off the difference between hours to Days! That is a HUGE amount of wasted energy just thrown away! All admitted by Minn Kota in this ad.