Lifepo4 trolling battery

[Ronbow]

Hi folks

So have you taken the plunge to Lifepo4 battery for trolling motor? And if so, experiences, recommendations, pitfalls?

My current 35ah SLA is about at the end of it's life. Been a good little work horse for 4 years, but also #25. Seeing Lifepo4 with reasonable BMS, 50ah, at 12# and now coming in at $150 to $490. Wow, big range in price. Yes, you get what you pay for, but some of the $200 units are getting good reviews, 90% four and five stars on hundreds submitted.

I have been using Lion car starter battery with 12V 5 amp connector for Garmin Striker 4 and it has been flawless, good for 16 hours and charges back in less than 2. Weighs 18oz. And also starts my 6L GMC, has flash light, will charge cell phone, has flasher light as well as SOS. Will not power an air compressor. Maybe some new ones will, all about amps.

So experiences? I will take the plunge this week, and report back when I do.

Ron

 

[Ronbow]

So just received my 35ah LiFePo4 battery. Under $130. Fit right into the Noco Snap Top U-1 box. Came basically fully charged, reads 13.4 volts. It is 12 pounds in the box and fully externally wired. Supposed to be 32 amp max continuous discharge so should run my 20# mini trolling motor. Tested and it ran fine through my PWM. Tomorrow on the water test.

Also got a Noco Genius 10 charger. It has a Lithium setting that will work with the BMS in the LiFePo4 battery. Also has a "repair" mode for SLA, and it did bring back my 35ah AGM to a higher level, though I think that battery has reached its useful life.

Why 35ah? I'm using it on a 7.5' Backwater and I'm really an indicator guy, or cast and strip as opposed to trolling all over the lake. So don't need 50ah, or 100 ah like the bass folks, or a higher trust TM. I should be able to run up to 36# motors with this set up.

Will post experience after on the water tests.

 

[Josh]

I have been using Lion car starter battery with 12V 5 amp connector for Garmin Striker 4

Can you talk more about this? I'm curious about the specific setup. I have a Striker 4cv.

 

[onefish]

I have a 110ah Dakota LiPO4. It is half the weight of a SLA and can be operated down to 5% reserve without damaging the battery. I like everything about the battery except the cost. If it lasts for 10+ years as is claimed it will be a great buy. I will get back to you in 9 years.

 

[iveofione]

Ron, thanks for the good information on your battery upgrade. A lot of guys aren't even aware of the presence and advantage of AGM batteries, much less the more advanced lithium based battery that you purchased.

I was glad to hear that your PWM ran fine with the new battery-another useful technology that not enough are taking advantage of. I could easily convert over to LiFe but have been fully vested in AGM for several years now and have 7 of them on my bench along with battery tenders to keep them fed. My identical 35 AH AGM's are used for my 28# thrust MinnKota, I always carry two but have never even run the first one down. These are used on my 8' pram and my Scadden Predator for getting around on the bigger lakes.

If I was starting over now there is no doubt that I would use the more modern batteries and would urge anyone thinking about trolling motor or depth finder use to familiarize yourself with the newer technology. My AGM's at 23# will run my boats all day, compare that to the traditional lead acid monster at 60-80# and it is no contest. No leakage either because the sealed batteries can be used in any position. The newer batteries will be half the weight of my AGM's but several times the cost. For your money you get a battery that will probably last for a decade, be a fraction of the weight and can be discharged safely down to about 10%. A lead acid battery gives up around 50%. Money well spent.

Anyone that has ever had a dead battery or thinks they could have should have one of those battery powered starting packs that Ron mentioned. They are amazing in their capability and so easy to use. A dead battery used to require a call for help and someone to show up with a big assed starter battery to get things going again. The new battery packs will start a big V-8 and are small enough to fit in some glove compartments. You can teach your wife how to use it in about 2 minutes and at some point it will save you a lot of grief. Around $100 depending on how much power you need. (Subaru owners who camp out of their rigs REALLY need one of these because leaving the rear hatch open even with the lights off can run down the battery. You can guess how I know this but there is a simple workaround. That's another story.)

 

[Josh]

A lot of guys aren't even aware of the presence and advantage of AGM batteries, much less the more advanced lithium based battery that you purchased.

I admit, I'm kinda clueless about them. I would love to know what to replace my big ass deep cycle with.

 

[Matt B]

I admit, I'm kinda clueless about them. I would love to know what to replace my big ass deep cycle with.

Yeah, I wouldn't mind having the PWM controller info and experience of this group over here on this site, too. That's something else, but related to running my trolling motor(s), that I've also been meaning to look into. When I bought my little smokercraft it came with two Minn Kotas and a big heavy lead-acid deep cycle battery so I've just been rolling with that, but I'm ready to find a better solution to battery power.

 

[Wanative]

My sled has a a 24v trolling motor and my back is ruined for a week each spring
when I lug those unbelievably heavy lead acid batteries out each spring to install them back in the boat.
This thread has me thinking seriously about new options.

 

[Sam Roffe]

I have a 110ah Dakota LiPO4. It is half the weight of a SLA and can be operated down to 5% reserve without damaging the battery. I like everything about the battery except the cost. If it lasts for 10+ years as is claimed it will be a great buy. I will get back to you in 9 years.

I think you will be very happy after 10 years. When you look at cost and energy, it will be cheaper over the 10 years than a lead acid battery

 

[iveofione]

Matt, just Google something like: "PWM controller for trolling motor" and a world of information will pop up. Same thing with YouTube to see a lot of how-to videos. The basic set up is 2 wires in from the battery and 2 wires out to the motor. Your grandmother could hook one up with a flat blade screwdriver.

MinnKota sells motors with built-in PWM circuitry but the tariff is over $100 more than the same motor without it. MK calls it Maximizer Digital Control. The PWM's we are buying to convert our motors to Maximizers cost on average about $25 and come with a forward/reverse switch, an off/on switch, a speed control knob and a digital readout panel that tells you what percentage of power you are using. I bought a plastic sandwich box at Walmart for a couple of bucks to put mine into. Be sure to provide ventilation.

What you will end up with is leaving your manual 5/3 speed motor in forward gear at the highest speed and doing all of the controls from the box you mount the unit in. In can be placed wherever convenient as you will no longer have to touch the motor except to steer. In my pontoon I mostly steer with my fins or oars. Battery life will essentially double and instead of 5 forward speeds and 3 reverse speeds you will now have infinite speed control between off and full power in both directions. One of the big gripes for guys with the standard motor is that speed #1 is still way too fast for normal trolling. The PWM solves that.

It is a fun and cheap project that has a lot of upside. To me the greatest advantage is being able to control the motor without ever reaching behind for off/on or to change speeds. It is as easy and convenient as the power window controls on your car.

 

[iveofione]

One thing I failed to mention is the use of quick connectors on the battery, PWM and trolling motor. I use the Anderson connectors but there are others that work also. The advantage of using these is that connection is instant as well as disconnection and is very positive. In the event that that the PWM should fail while in use (usually due to overheating) you can simply disconnect it from use and plug the motor directly to the battery and return to normal use.

I'll post some pics soon to show my entire setup.

 

[Josh]

So just received my 35ah LiFePo4 battery. Under $130.

@Ronbow which battery did you end up getting?

 

[Ronbow]

Which battery did I chose? As mentioned, my boat is small, as is my TM, and I really use it to get from place to place rather than trolling. And I had a Noco U-1 box already, and have been fine with a 35ah AGM, until it entered old age (like me) and started to have lapses (like me...).

What you look for, as best as I can tell is, sufficient ah for your needs, size, weight, warranty and continuous amp output. TM's have a fairly high draw; mine is max 20, a Minn Kota C-2 30# is 32, and a Newport NV 36# is 29. These would be a likely replacement if my 35 year old motor decides to retire (like me). So I went with a good review battery, that fit in my box, and was at least 35ah, and had at least 32amp CMD. It is the Miady. $129 Amazon. Also liked the looks, reviews of the Zoom 50ah, Ampere Time 50ah, and Dakota 50ah, the latter a lot more $, but local should there be an issue.. Just felt I didn't really need the extra power (Tim the tool man might disagree...) BTW, a direct replacement for my current AGM is $109......

From what I read, these things either fail rather quickly, or will out live me. So get 'em tested and cycled a few times, to take advantage of Amazon return or warranty.

Ron

 

[iveofione]

The pictures will show the 3 pieces not connected, connected, the installation in the box, the controls with readout, forward and reverse and speed control and the PWM bypassed with the battery into the trolling motor. Very similar to Ronbow but with quick connects. Note the very large ventilation holes in the box. There are more that aren't visible.

 

[Ronbow]

Ok, day one is water under, well the boat. Six hours on the water. Ran the length of the lake twice. Trolled for maybe an hour. Meter still reads 100%, voltage constant at 13.3.
Wish I had as good luck with truck. Battery dead as doornail, because I failed to unplug add on Garmin GPS backup camera (see other thread). Used my Li ion unit car starter/fish finder battery/flashlight to start (see other thread). So all good. Sort of.....

Oh, got six to the boat largest 21"

Ron

 

[Ronbow]

Ok, day one is water under, well the boat. Six hours on the water. Ran the length of the lake twice. Trolled for maybe an hour. Meter still reads 100%, voltage constant at 13.3.
Wish I had as good luck with truck. Battery dead as doornail, because I failed to unplug add on Garmin GPS backup camera (see other thread). Used my Li ion unit car starter/fish finder battery/flashlight to start (see other thread). So all good. Sort of.....

Oh, got six to the boat largest 21"

Ron

OK, got an aux plug for 12 volt, like the cigarette lighter, some #14 wire, and an "add a circuit fuse tap" (very cool idea). Replaced the ignition fuse with the tap, put both fuses in, drilled a hole through the center console, wired it all up and now the GPS comes on automatically when the ignition is on. No more dead battery!!

 

[cdnred]

Late to the game but I'm looking to pickup a 12v 35-40ah (min) battery for running my Minn Kota Endura 34lb, 36in trolling motor that I just bought. I'm looking to add a depth/fishfinder and a possible 12v auxiliary plug in the future that I planned to hook into the system as well. I'm looking into just going from point A to point B and not trolling so I don't need a huge battery for getting around. These LifePO4 batteries seem to fit the bill for what I need plus I'm able to discharge to near empty without worry about damaging the battery..

I'm curious about battery chargers as some point out that chargers intended to be used for lead acid batteries aren't recommended for lithium style batteries. Any suggestions or comments regarding battery chargers to use on a LifePO4 battery..?

 

[Ronbow]

Do check the max amp draw of your motor and be sure the LiFePo4 has the guts to match. All the higher price ones will be fine. My little TM only max draw 20 amps. Think I saw yours might be up to 42 amps?

Charger, I went with the Noco Genius 10 which can do 6 or 12 volt, and has settings for SLA, AGM, Lithium, and a "repair" mode. A bit pricy. My old charger still worked, but this new one is smaller and likely the tech updates are worth it. Or not......

Many LiFePo4 come with a paired charger. I did want 10 amps; most of the paired are smaller which just takes longer. Not that I am in a hurry.

 

[cdnred]

I was looking at perhaps getting either the Amazon 12v 36ah or the 12v 40ah that comes with a charger. I think I should be safe with either one for my motor. I've heard about differences in charging rates between the lead acid batteries and the LifePO4 batteries so in that case I maybe better to just go with the Amazon 12v 40ah that already comes with the charger..

https://www.amazon.com/Miady-Phosphate-Lightweight-Replacement-Applications/dp/B089SDC497/ref=sr_1_17?crid=2W5BU0PUX4ZB&keywords=12v+lifepo4+batteries&qid=1649333185&refinements=p_72%3A1248861011%2Cp_36%3A1253496011&refresh=1&rnid=386419011&s=automotive&sprefix=12v+lifepo4+batteries%2Caps%2C126&sr=1-17

https://www.amazon.com/phosphate-Rechargeable-Charging-Discharging-Performance/dp/B08G89TJX8/ref=sr_1_27?crid=2W5BU0PUX4ZB&keywords=12v%2Blifepo4%2Bbatteries&qid=1649333279&refinements=p_72%3A1248861011%2Cp_36%3A1253496011&refresh=1&rnid=386419011&s=automotive&sprefix=12v%2Blifepo4%2Bbatteries%2Caps%2C126&sr=1-27&th=1

Based on the chart below showing a 30lb drawing 30 amp max and a 40/45lb drawing 42 amps max, I'd assume my 34lb should draw in the 34-36 amp max range..

 

[cdnred]

Okay, I bought a LifePO4 12v 40ah battery for running my Minn Kota 34lb and was intending to put it inside a plastic ammo box that's water tight and sealed. Question I have now is should I drill some holes in the lid for venting..? I know the lead acid batteries should be vented but not sure whether that applies to these LifePO4's as well..

edit: I thought I found the answer but then I found two different opinions so now I'm not sure which is corect but perhaps it's best to vent just in case..

One comment found on google search..
A lightweight option which offers charging efficiency and between 3000-5000 life cycles makes LiFePO4 the best choice for a better battery. To ensure the utmost safety and minimal impact, our chemistry utilizes only environmentally acceptable materials and has zero emissions with no venting needed.

From another comment found on google search..
While lithium batteries don't produce gas the same way the other two batteries do, they still require ventilation to prevent thermal runaway. If the battery gets too hot, it can reach a critical condition and explode.