Lithium Battery Question - 50AH LiFeP04 for a 55# thrust Minn Kota?

[Buster]

I have been told the battery meter built in the head of an electric motor and standard lead acid battery meters will not work with this battery. What battery meter are you using.

What you've heard is correct. The reason is clear in my earlier post with the discharge graph. Simple voltage meters work by measuring voltage of the lead acid battery. The voltage curves are different for different batteries. There are numerous battery meters available. I use the Victron SmartShunt and it's great, although expensive. Make sure you get a waterproof version or have a safe location in the boat for it.

 

[Shootstraight]

I have a Terrova 24 volt and some places are saying that I two 100 amp hour,and others two 65 amp hours. And at roughly $800 each or more, I'm very leery of dropping that kind of money. But I did get a 12 volt 33 amp hour lifepo for my electronics at$249.99 and I consider that a good deal. Some places are just trying to get as much money as they can before the prices start to drop significantly.

Two 50 amp Ionics would work fine. I have one 50 on my 12v Terrova and in six hours of fishing it’s still around 90%. Now I don’t have all electric, just use it for normal shore usage and holding Spotlock on points etc.

 

[dcbz]

For those that might have wondered about the useful discharge capacities and discharge efficiencies of Li ion vs Pb acid batteries, this chart from RELiON batteries might prove useful: Comparing Lithium Iron Phosphate with Lead Acid Batteries | RELiON
My main concern about Li ion batteries would be safety. I am confident that LiFePO4 chemistry is stable (I am a chemist). I have not studied the other Li ion chemistries enough to comment one way or the other. What I would make sure of before laying down my hard earned cash is that the batteries that I bought were UL or CSA (the Canadian equivalent of UL) certified. While LiFePO4 might be stable, and most cells come from a few factories, different manufactures' battery management systems (BMS systems, an integral part of most batteries) might differ a great deal from each other and I would want the peace of mind in knowing that they were tested for safety by a third party, especially since I charge my batteries in my attached garage. I certainly wouldn't overlook the importance of third party testing in this new (relatively speaking) and rapidly changing technology. I know that not many house fires are caused by Li ion batteries, but there will be more as more people put them in their boats or buy bicycles with Li ion batteries in them. Of the bicycle related fires that I have read about, none of them were started by batteries that were UL or CSA listed. A final note on the safety of batteries... Third party testing from UL and CSA testing is expensive and companies that go through the trouble of keeping their buyers safe will be proud of their UL marks. If you cannot find out whether a battery has gone through third party testing on a manufacturer's website, you can probably assume that it has not. I am not advocating for or against any type or brand of battery, but Dakota batteries are UL listed: Certifications & Quality - Dakota Lithium Batteries
So are RELiON batteries: Lithium Iron Phosphate Battery Certifications | RELiON
I am sure that others may be too. I would certainly check.

 

[InSaneFisherMan]

I have been told the battery meter built in the head of an electric motor and standard lead acid battery meters will not work with this battery. What battery meter are you using.

You can get good accuracy from a standard volt meter for LifePo4, most important is cutoff volage is around 10.4v for a 12v battery. That's when the BMS shuts down the battery.

If you look at the attached file, a lifepo4 at 12.5v has 14% capicity, if using a meter for a standard SLA battery, this voltage would indicate a fully charged battery.

 

[airshot]

If they are starting out over 14 volts, no wonder the trolling motors are faster !! By turning down the speed control to get less speed tour motor will use less battery power, thus making the battery charge last longer. Looking more and more positive for the Lifepo4 batteries !

 

[InSaneFisherMan]

If they are starting out over 14 volts, no wonder the trolling motors are faster !! By turning down the speed control to get less speed tour motor will use less battery power, thus making the battery charge last longer. Looking more and more positive for the Lifepo4 batteries !

14.6 is for charging, 13.6v is a full battery.

 

[Gstevens]

Update : I have been running my relion 50AH lifepo4 battery hard with multiple boats and its running and charging great. Dakota Lithium warranty replaced my 1 year old 60 AH dual starter/ deep cycle battery and it just came in- I will use it and update on functionality. It worked great all last year with starting a 20hp Suzuki, running a 7” garmin chartplotter fishfinder and Terrova 55lb with ipilot. I move the relion around between boats as its so light to pull and charge for boat off trailer, boat in trailer and as a deep cycle only supplement. I wired a marinco 3 prong plug into the minn kota battery box and can plug the bow mount 55 lb Terrova or 55 lb powerdrives from two other boat easily. One of the three boats has spent last 6 weeks in garage getting some fiberglass repair and bottom painted with herculiner… my aluminum boat just doesn’t need this level of coddling!

 

[sonny.barile]

I use a multimeter to check my voltage……….

 

[sonny.barile]

14.6 is for charging, 13.6v is a full battery.

Lifepo4 batteries can still read 14+ for hours after charging, then they settle down to 13.6 ish…….People test them right away and think it’s super high voltage.

 

[airshot]

Lifepo4 batteries can still read 14+ for hours after charging, then they settle down to 13.6 ish…….People test them right away and think it’s super high voltage.

Glad to know !! However, they are still a full volt higher to start so my same logic applies.....
My last question is...using my 12 v 55 lb powerdrive MK motor would two 50's or a single 100 give me the longest run time. Currently have two gp 31 agm batteries and can get up to 8 hrs trolling time.

 

[sonny.barile]

You won’t notice any difference.

 

[Skunked again]

View attachment 115533

That thing is beautiful!! Great work !

 

[AlanT]

For those that might have wondered about the useful discharge capacities and discharge efficiencies of Li ion vs Pb acid batteries, this chart from RELiON batteries might prove useful: Comparing Lithium Iron Phosphate with Lead Acid Batteries | RELiON
My main concern about Li ion batteries would be safety. I am confident that LiFePO4 chemistry is stable (I am a chemist). I have not studied the other Li ion chemistries enough to comment one way or the other. What I would make sure of before laying down my hard earned cash is that the batteries that I bought were UL or CSA (the Canadian equivalent of UL) certified. While LiFePO4 might be stable, and most cells come from a few factories, different manufactures' battery management systems (BMS systems, an integral part of most batteries) might differ a great deal from each other and I would want the peace of mind in knowing that they were tested for safety by a third party, especially since I charge my batteries in my attached garage. I certainly wouldn't overlook the importance of third party testing in this new (relatively speaking) and rapidly changing technology. I know that not many house fires are caused by Li ion batteries, but there will be more as more people put them in their boats or buy bicycles with Li ion batteries in them. Of the bicycle related fires that I have read about, none of them were started by batteries that were UL or CSA listed. A final note on the safety of batteries... Third party testing from UL and CSA testing is expensive and companies that go through the trouble of keeping their buyers safe will be proud of their UL marks. If you cannot find out whether a battery has gone through third party testing on a manufacturer's website, you can probably assume that it has not. I am not advocating for or against any type or brand of battery, but Dakota batteries are UL listed: Certifications & Quality - Dakota Lithium Batteries
So are RELiON batteries: Lithium Iron Phosphate Battery Certifications | RELiON
I am sure that others may be too. I would certainly check.

Great information. Thanks for posting. I noticed that some manufacturers specifically state the certification is on the cells. (Not the links you provided.) It appears they are not referencing the BMS in the certification. Do you know if the certification on the cells only? I have a tendency to pick apart marketing information to determine the information they are NOT telling me.

 

[sonny.barile]

I see it suggested a lot to look for batteries that specifically state use of Grade A automotive cells. Some of the strangely named batteries on Amazon are not……or they may use outdated BMS without thermal controls. If a deal seems too good to be true…..it usually is.
As stated earlier…..Buy from companies that have long been in the power business. This is fairly new tech in comparison to the standard and the bulk of information is coming from “influencers”. So we are all learning……..Better to be safe than sorry when adopting new hazardous tech. A reputable established company is going to try hard not to put out something that tarnishes the name.

 

[thill]

This is interesting to me. I see some "strangely named" batteries on Amazon for about half the price of many I see here.

Many are $159 - $169 and most have hundreds of reviews with 4.5 star ratings. Eco-Worthy, Nermark, and a few others have thousands of reviews and still maintain a very high rating. Very few failures, and the few duds replaced with a fairly simple process.

There are others that have 3 and 4 stars, but when you read the reviews, the customer service is lame.

I am considering buying two 50AH batteries for my 24V Terrova from the better reviewed economy batteries. The economics and numbers seem to support this.

That being said, I've had them in my cart since the beginning of this thread, but haven't pulled the trigger yet. Wimp!

 

[lightflyer1]

I am gambling on a couple of these myself. Got them the other day. Well packaged and look good so far. Need to try them out though.

 

[thill]

View attachment 115533

Awesomely clean build! VERY nice!

 

[thill]

I just watched this video, and this may steer me to go with the TimeUSB Pro 100 AH battery for $279:



Obviously, I can't use it for my 24V at this time, but IF I get it and IF it works as well as advertised on my 55# Riptide, I can buy another one later for the bigger TM.

 

[moedelawn]

The 12v 50ah Time Usb was on sale for 169.00. I thought about it for a while but decided I will go with a single 24volt. Whenever that will be.

 

[LDUBS]

This is interesting to me. I see some "strangely named" batteries on Amazon for about half the price of many I see here.

Many are $159 - $169 and most have hundreds of reviews with 4.5 star ratings. Eco-Worthy, Nermark, and a few others have thousands of reviews and still maintain a very high rating. Very few failures, and the few duds replaced with a fairly simple process.

There are others that have 3 and 4 stars, but when you read the reviews, the customer service is lame.

I am considering buying two 50AH batteries for my 24V Terrova from the better reviewed economy batteries. The economics and numbers seem to support this.

That being said, I've had them in my cart since the beginning of this thread, but haven't pulled the trigger yet. Wimp!

I see the same thing with a lot of other products on Amazon. It typically leaves me scratching my head. Clearly a lot of these items are made in SE Asia. Some are well made and some junk. @dcbz mentioned UL listing (and other recognized testing labs) above. That might be a good indicator for an important component from an unknown brand.