"Cheap" LiFePO4 drop-in update

[sailorboy1]

Just an info update:

I have now had my $306 100Ah LFP drop-in Power Queen batteries 11 months (they are cheaper now). They are still babies really for LFP batteries and I have 4 of these for a 400ah house bank. These batteries have mostly only been charged by solar. They of course charge via the alternator while motoring and once in a while they get charged via battery charger either using shore power or my Honda EU2200. For the most part they operate in the range of 60-100% state of charge. So far the biggest problem turned out to be the idiot that installed them (me) not tightening all the terminals.

Since it has been cloudy for 4 days it seemed a good time to test them for the first time before heading out again in couple of months. So I just let them run down a couple days and then hurried the discharge along today by turning on every DC load I could. I finally stopped after -342Ah, which works out to be 14.5% charged by the math and was 19.6% by the battery monitor that has a PF of 1.05 programed into it. Voltage after a 10 minute wait with all DC power off was 12.67V, which works out pretty much to be about 15% SOC on most curves.

So my cheap batteries look good!!! they may have gone up in voltage more, but I wanted to turn the lights back on. In normal operation I never would have let my batteries get so low and the only time would be if I was gone a long time and solar failed or it was cloudy 4 days.

And to note I made NO changes to my electrical system at all changing from acid batteries to the LFPs. I had a "cruiser" type system already and all I did was change the various setpoints. Right now the charger is running on an AGM setting that will charge back o 14.1V and then float at 13.4V. That probably wouldn't be 100%, but who cares and I probably will turn it off once batteries are back in the 90% range.

Now I will say this, the same great things could have been written about my last set of FireFly carbon foam acid batteries at this time of use. Those lasted 2.5 years and then died a death that exactly matched partial state of charge problems they were not suppose to have.

[Fintry]

They look great on paper, and the price is certainly right, but 5% of the Amazon reviews are damning. Victrons and other name brands are 4 times the price, but what is peace of mind worth?

[Chotu]

Originally Posted by Fintry

They look great on paper, and the price is certainly right, but 5% of the Amazon reviews are damning. Victrons and other name brands are 4 times the price, but what is peace of mind worth?

Maybe, but you can replace the Amazon drop ins 4x for the same price. I took my chances on the drop ins. Very happy I did. At 13 months on mine. Flawless

[sailorboy1]

Originally Posted by Fintry

They look great on paper, and the price is certainly right, but 5% of the Amazon reviews are damning. Victrons and other name brands are 4 times the price, but what is peace of mind worth?

definitely not 4x the price

I can easily find as many damning Victron reviews

BTW I don't care what batteries others get. I posted a review of what my batteries have done.

[Iron E]

Originally Posted by sailorboy1

BTW I don't care what batteries others get. I posted a review of what my batteries have done.

I'm sure it's pretty satisfying.

I'll be moving from the AGM bank I have next Summer. I probably still have a couple of years left on them but I'm wanting to double my AH's.


Curious, do you still have a separate start battery, or did you just go with 1 battery bank?

[sailorboy1]

Originally Posted by Iron E

I'm sure it's pretty satisfying.

I'll be moving from the AGM bank I have next Summer. I probably still have a couple of years left on them but I'm wanting to double my AH's.


Curious, do you still have a separate start battery, or did you just go with 1 battery bank?

I have an acid start battery, the house feeds into it also

[grantmc]

For really CHEAP they also sell used batteries:
https://ipowerqueen.com/collections/like-new-batteries

[UFO]

Originally Posted by Fintry

They look great on paper, and the price is certainly right, but 5% of the Amazon reviews are damning. Victrons and other name brands are 4 times the price, but what is peace of mind worth?

LOL 4 x The price... And SOME!


I picked up 1120Ah EVE (16 Cells) direct from China for US $1850 Delivered a few years ago and they have not missed a beat, I dread to think how much the Victron equivalent would be... They were not drop in though and I did incur about another 3K setting the system up.

[Letterkenny]

I am very happy so far with my LiTime bank of 4x 100ah mini model. Got all with CA sales tax for under a boat buck. I heard some say just to do one larger but this is partially my redundancy as if one has the BMS or something crap out, I have three left. I am also running an AGM start.

[Ixium]

Will prowse does great reviews of the cheap batteries. Tests, tips them apart, etc

Currently have firefly batts that are 5+ years old from the previous owner, but if/when they go I’ll be using Will’s videos to find some decent replacements.

[jcapo]

Sailorboy, did you cable battery to battery as is common with lead acid or cable each battery to a bus bar?

[sailorboy1]

Originally Posted by jcapo

Sailorboy, did you cable battery to battery as is common with lead acid or cable each battery to a bus bar?

cabled as normal for acid batteries in parallel

[JBP]

I also really like my drop in. I tripled my battery capacity by switching out my old 75 Ah FLA for a 100 Ah LFP on my wee little boat. But I still get nervous when it drops below 50%. I have to tell myself "it's fine. It's supposed to go below 50%. Still plenty of power left. "

[pbiJim]

Originally Posted by sailorboy1

Just an info update:

I have now had my $306 100Ah LFP drop-in Power Queen batteries 11 months (they are cheaper now). They are still babies really for LFP batteries and I have 4 of these for a 400ah house bank. These batteries have mostly only been charged by solar. They of course charge via the alternator while motoring and once in a while they get charged via battery charger either using shore power or my Honda EU2200. For the most part they operate in the range of 60-100% state of charge. So far the biggest problem turned out to be the idiot that installed them (me) not tightening all the terminals.

Since it has been cloudy for 4 days it seemed a good time to test them for the first time before heading out again in couple of months. So I just let them run down a couple days and then hurried the discharge along today by turning on every DC load I could. I finally stopped after -342Ah, which works out to be 14.5% charged by the math and was 19.6% by the battery monitor that has a PF of 1.05 programed into it. Voltage after a 10 minute wait with all DC power off was 12.67V, which works out pretty much to be about 15% SOC on most curves.

So my cheap batteries look good!!! they may have gone up in voltage more, but I wanted to turn the lights back on. In normal operation I never would have let my batteries get so low and the only time would be if I was gone a long time and solar failed or it was cloudy 4 days.

And to note I made NO changes to my electrical system at all changing from acid batteries to the LFPs. I had a "cruiser" type system already and all I did was change the various setpoints. Right now the charger is running on an AGM setting that will charge back o 14.1V and then float at 13.4V. That probably wouldn't be 100%, but who cares and I probably will turn it off once batteries are back in the 90% range.

Now I will say this, the same great things could have been written about my last set of FireFly carbon foam acid batteries at this time of use. Those lasted 2.5 years and then died a death that exactly matched partial state of charge problems they were not suppose to have.

Thank you for this report. I am just starting to dabble with these, now that built in BMS systems, that appear to be ABYC E-13 compliant, have become commonly available. ...and the prices have come down.

I have read that these batteries are happiest running in the charge range of 20-80% & that they suffer from 100% state of charge as much as they suffer from very low state of charge. But this is just what I have read. I have not confirmed this with my own tests. I value first hand accounts like the one you provide here.

I think it was Wired magazine that recently carried an article explaining why lithium batteries don't like 100% SOC. It had something to do with an internal matrix collapsing.

Lead batteries love 100% SOC on a regular basis. That has been well documented for many years. Lithium, perhaps may present a different story, but I am still collecting data.

[sailorboy1]

Originally Posted by pbiJim

I think it was Wired magazine that recently carried an article explaining why lithium batteries don't like 100% SOC. .

Well if you can find an actural test that says that I would be interested in seeing. I am sure Wired is just parroting the same old same old under the "if it is on the internet it must be true" thinking. I have yet to find a real TEST that really shows a problem. The closest I have found was a storage test that showed a 3% capacity lost on LFP batteries STORED at 80-100% as compared to 40-80% after being that way for 9 months. To me that is a lot of worry about nothing.

But are you planning to just leave your battery at 100% all the time? My bank normally gets to 100% on 90% of days, but it is cycling all the time with use.

Batteries are consumables on boats, even LFP ones.