LiFePO4 – It’s a chemical Equation – Lithium Iron Phosphate

The new LiTime batteries has caused a lot of consternation

After watching a lot of YouTube videos the past year or so about Lithium Iron Phosphate batteries (LiFePO4) I was thinking about making the switch.

Then about a month ago one of my favorite Youtubers, who has The Engineered Angler channel did a two-part series on his decision to make the switch from Lead/Acid batteries to LiFePO4. Franco did a great job of convincing me that I too should make the switch. Afterall, the two lead acid batteries I had hooked up in series to create a 24 volt system to run my Minn Kota Terrova trolling motor were not holding their charge very well. I bought a load testing device and it proved what I already knew. That being that it was time for me to use them to save the core charge when I would purchase the LiFEPO4 batteries Franco had switched to.

I think Franco got his on the cheap or perhaps free from a company that was once named Ampere but is now LiTime (that’s short for Lithium Time and not Lee Time as many are calling it on YouTube). Franco did some great tests and gave his new batteries a rave review. 

So I bought two of them as well on the 4th of July. 

That’s when this mini adventure that has taken 26 days to get correct started. Yes, 26 days. I am writing this story as an educational review to make you aware of how this switch should take place.

It took about 10 days to get the batteries. Of course when they arrived it was like Christmas for me. At least it was in terms of my excitement. I don’t normally buy myself Christmas presents and if I did I would not spend $700+ dollars.

Yes, $700+ but that includes a 29.2 volt battery charger for Lithium Iron Phosphate batteries from LiTime. From here on out I will just call them Lithium batteries and chargers. 

The batteries arrived both showing a SOC (State of Charge) of 13.2 volts. According to the chart in the owner’s manual a 13.2 charge is equivalent to a 75% charge in them. Check the chart below to see how it all looks.

SOC (%) Voltage (V)

0 10 to 12
25 13 to 13.15
50 13.15 to 13.2
75 13.3 to 13.33
100 > 13.33

At the time and after chatting with technical experts at Johnson Outdoors I was told that I should have purchased two 12v chargers for LiFePO4 Batteries although one said I could use my current Minn Kota Digital two-bank charger to get the job done. However, to keep the warranty I needed to use a lithium charger or a 24 v lithium charger. I bought the 29.v 20 amp charger from the same company that I bought the batteries from.

The batteries come with a five-year warranty and are good up to 4000 cycles. That means I can run them down to nearly nothing and recharge them fully that many times. Many of the comments of Franco’s channel from his followers say that they seldom recharge them. Like 20-30 hours of use from them before charging.

In this entire process I actually managed to get my two batteries at different levels of charge. One was at 13.2 while the other was at 13.33. In order to recharge them with my 29.2v 20 Amp charger I needed to either charge up the 13.2 battery or discharge the 13.33 battery. I can’t charge one battery with a 29.2 v charge so I had to come up with a way to discharge just the one . 

Here was my system. 

I tried sticking the 12 volt trolling motor that came with my latest boat, the SeaArk, then filled a large tote with enough water from Rocky Run Creek to emerge the entire propeller in water. When I turned it on, water flew all over me, the floor, and anything near the motor. I quickly turned down the speed to 1. At that low level the motor would use less power and it still slurped, and slurped enough to add water to the floor of the garage. That didn’t bother because what garage floor doesn’t need a good washing? I turned it off a couple hours later and tested the voltage. Yikes! My battery still had 3.3 volts in it. 

The next morning when I went out to get the motor going again I was shocked when I saw that the tote I had under the water-filled tote had collapsed, spilling more water on the floor and breaking the cover on the bottom tote. The trolling motor idea wasn’t a good one.

In series my two batteries tested 26.4 volts which is plenty to run my Terrova 24 volt trolling motor so I did just That. I fished on Saturday, July 23rd with a new fishing partner ( a story to be told this week so stay tuned), I fished again the next day then fished two more days with Davy and on Thursday I went on the river alone and for an hour used only the trolling motor to go a mile up the river at a speed of 8 on the control or between 0.9 mph to 1.2 mph depending on the strength of the river current where I was. I did not recharge either battery after all that fishing. I figured there were about 17 hours of trolling motor operation and my batteries dropped to only 26.3 and actually the SOC Friday morning was 26.4

Even with that, 26.4 is only a 75% state of charge and I want a fully charged system. I decided to try another method to get my two batteries to the same State of Charge when they are at rest. 

A lot of years ago I purchased a used Lowrance Lo-K -Tor flashing fish finder. It was one of the original depth finder/fish locators ever produced. Old guys like me probably remember the green box that opened up to show a circular dial that lit up with a flashing light showing the depth a boat was and sometimes showed other blips on the dial if fish were between the bottom and the transducer. The power for those Lo-K-Tors was a pair of six volt batteries with the coils on the terminals and a simple circuit board that the batteries sat upon to give it power.

Over the course of several decades I accumulated a small collection of those green boxes and got them all working. I have transducers for them but I run them off small 12 v 9 AH or 7 AH batteries or I have even just hooked them up to my starter battery since it is 12 volts. It works and it’s fun from time to time to fish with original electrical technology. So today I hooked up all four of those green boxes to my battery that was higher in voltage than the other in an attempt to get it down to a restring charge of 13.20 volts. 

Laugh you might but it has worked better than the trolling motor attempt. I hooked up all four green boxes at 1 pm today. It’s now 8:50 pm at last check the battery is down to 13.20 volts under load but after resting for 30 minutes it’s at 13.21. So, I have to get it down one more tenth of a volt to even them out. When I accomplish that I need to connect the batteries in parallel for 24 hours in order for the BMS to balance them. Then I can fully charge them with the 29.2v 20 AH battery charger.

So there is some modern technological information for you. I always try to do several things within these Oshaukluta Outdoors stories: 1) entertain you 2) educate you 3) laugh at myself and hope that combination keeps you clicking in when I post a story.

I have four or five more stories in the hopper right now, including an exciting day in a new War Eagle with a Kowald, a day of learning about fishing from a 16-year old who is a great fisherman, several trips with Davy and my solo trip to explore a “Northeast Passage” on the Wisconsin River between the Dekorra landing and Portage.

Leave a comment if you’d like to and tell your outdoor friends about the stories. On Saturday met two people who read and enjoy the stories. The Second Bob’s parents were at the Lake Chippewa Campgound with the Second Bob, his wife and Larry and Mary, their sidekicks. Karol and I surprised them at the campground when we drove over there from our retreat west of Minong, WI.

Have a great day. If you have questions about LiFePO4 just click into YouTube or call me but remember – I do not consider myself a technical expert in the LiFePO4 field. I am an active learner though.

Bob