What do folks think of these cells?

[Dr. Dickie]

So, I am looking to add to my Powerwall (right now 14S 160p) as I feel I need more capacity. I would like to add 100 cells to each pack (I can simply stack a 100 P pack on to the back of existing packs to do this). My packs were made 100% of LG M26 (2600 mAh) cells gotten from medical packs that battery clearing house had. Sadly, those packs are gone. I have been looking for cells that would be close to the same capacity, as obviously if the add-on cells are of lower capacity, it will simply reduce the increase.
I found these:

3s3p Molicel Module with 9 2600mah 18650 Philips 86.58wh

Here are really nice Molicel medical modules. These have 9x ICR-18650K 2600mah cells inside and are in 3s3p configuration. The greatest thing about medical batteries is they don't get cycled too many times before they get recycled so these cells you can expect pretty good capacity readings. Also...

batteryhookup.com

I was so damn spoiled getting those LG cells for $0.50 a piece, it would hurt to get these, but they look like they would be a good fit. Anyone have any experience with these Moli Energy ICR-18650K cells?
Thanks

 

[Wolf]

I ran the ICR-18650K cell through my data and found I had processed 59 of them. Manufactures shows ≤80mΩ for acceptable IR and dam if they aren't spot on. Preferable would be <60mΩ..
Not a bad cell but the high IR kept me from mixing them into my powerwall.
If in a pack / battery by themselves or mixed with equal capacity and IR cells they should perform just fine.
Paralleling them into existing packs IDK. The study of how cells behave in parallel points to different discharge and charging curves.
That being said if the amp draw is low enough and the voltages stay between 4.1V to 3.65V I dont think there would be much of a problem
considering the volume of cells. (260 per pack)
I personally would build a seperate battery and parallel it into the system #1 for ease of maintenance if required and #2 so I can isolate that battery in case those packs / battery doesn't play well with the others.
Wolf

 

[Dr. Dickie]

I ran the ICR-18650K cell through my data and found I had processed 59 of them. Manufactures shows ≤80mΩ for acceptable IR and dam if they aren't spot on. Preferable would be <60mΩ..
Not a bad cell but the high IR kept me from mixing them into my powerwall.
If in a pack / battery by themselves or mixed with equal capacity and IR cells they should perform just fine.
Paralleling them into existing packs IDK. The study of how cells behave in parallel points to different discharge and charging curves.
That being said if the amp draw is low enough and the voltages stay between 4.1V to 3.65V I dont think there would be much of a problem
considering the volume of cells. (260 per pack)
I personally would build a seperate battery and parallel it into the system #1 for ease of maintenance if required and #2 so I can isolate that battery in case those packs / battery doesn't play well with the others.
Wolf
View attachment 25607

Thanks Wolf. Yeah, didn't think the IR would be different.
"I personally would build a separate battery and parallel it into the system #1 for ease of maintenance if required and #2 so I can isolate that battery in case those packs / battery doesn't play well with the others."

Mmmm, interesting. I could do that. But yeah, the IR difference is concerning.
Would require me doubling my Longmons, not sure if they could just go right into the BMS or not. I will have to look into that.
Not in any great hurry, so I may hang on and see it some M26s pop up somewhere.
Again, thanks.

 

[floydR]

check battery clearin house again they found some when they moved grey LG M26 2600mAh 10A Lithium Ion cells in 10 packs 200 cellsm ninebot packs and Purple LG M26 2600mAh 10A Lithium Ion cells in 10 packs 200cells in nine bot packs. They might have the cells you need. if you were closer I would sell you some of mine.
Later floyd

 

[Dr. Dickie]

check battery clearin house again they found some when they moved grey LG M26 2600mAh 10A Lithium Ion cells in 10 packs 200 cellsm ninebot packs and Purple LG M26 2600mAh 10A Lithium Ion cells in 10 packs 200cells in nine bot packs. They might have the cells you need. if you were closer I would sell you some of mine.
Later floyd

Yeah, saw that, thanks.
The grey ones are the Chinese version, which makes me skeptical. However, I did get some of the grey ones before, and they tested okay.
Problem, is they only have about 3 packs, no where close to the number I need.
However, I have been thinking about this.
The largest draw from my pack I have seen (when the wife uses her iron with lights, fan, fridge, etc. on) is close to 30 amps. I am going to add a couple of misc areas in the house to the system, but it is all minor stuff (bathrooms). So let's say a max discharge of 40 amps, heck let's say 50 amps just to be on the safe side. With 14S 160+100 P, that would be a whopping 0.19 amps per cell, right? 50 amps spread over the 260 cells.
Would the IR mismatch really cause that much of a problem at that low draw? I guess being 80< mOhms compared to the 40< mOhms of the M26 cells that is pretty large difference, but even so. I would think the IR imbalance would be problematic at a high discharge or charge rate, and I am no where near that (max charge I have seen is 28 amps).
Still I will keep searching for about 2K of the M26 cells for a while longer; or at least look for cells with comparable IR and capacity.

 

[Wolf]

Gray ones are fine as they are built to LG specs whether Chinese or Korean.
I hate to break it to you but the purple LGGBM261865 and LGEBM261865 are made in China.
What makes you think Korea wouldn't outsource to China for cheaper labor. The US tech industry in not the only whore in the world.
My third battery is all gray LGFBM261865 and it performs just fine with an average IR per cell of 38.8mΩ.
Depending on your choice you could mix purple and gray it seems that battery clearing house has 5 of the purple and 5 of the gray 200 cell packages.
Wolf

 

[Dr. Dickie]

Gray ones are fine as they are built to LG specs whether Chinese or Korean.
I hate to break it to you but the purple LGGBM261865 and LGEBM261865 are made in China.
What makes you think Korea wouldn't outsource to China for cheaper labor. The US tech industry in not the only whore in the world.
My third battery is all gray LGFBM261865 and it performs just fine with an average IR per cell of 38.8mΩ.
Depending on your choice you could mix purple and gray it seems that battery clearing house has 5 of the purple and 5 of the gray 200 cell packages.
Wolf
View attachment 25611View attachment 25613

Yeah, but those are for Canada only (from what it says).
I was just in contact with Dan from Battery clearinghouse, he said that they had 4 or the rubber med packs. I told him that I needed 11 or 12.
Then had to run a quick errand. I was going to go and get the 4 for now.
They are listed again as sold out!!
I cannot believe I missed that quickly!

 

[OffGridInTheCity]

Yeah, but those are for Canada only (from what it says).
I was just in contact with Dan from Battery clearinghouse, he said that they had 4 or the rubber med packs. I told him that I needed 11 or 12.
Then had to run a quick errand. I was going to go and get the 4 for now.
They are listed again as sold out!!
I cannot believe I missed that quickly!

Getting the right quantity of cells at the right time can be difficult. In the early days I would buy 'a sample' (to verify) but then the source would be OUT. This puts you in the position of buying (large) quantity you might need based on the description alone - which is why there are so few places I trust. Its just difficult sometimes

 

[Wolf]

CA only that's odd. I wonder why that is? I would question that if I wanted to buy the lot.
So far BCH has not disappointed me yet.
Wolf

 

[Dr. Dickie]

CA only that's odd. I wonder why that is? I would question that if I wanted to buy the lot.
So far BCH has not disappointed me yet.
Wolf

I asked Dan, and he said, yeah Canada only. And he confirmed, someone sniped the 4 of rubber lots under me!
Dang it, just had to run out for 20 minutes!
I am committed to finding these. Or maybe I just should be committed! not sure which.

 

[Dr. Dickie]

Getting the right quantity of cells at the right time can be difficult. In the early days I would buy 'a sample' (to verify) but then the source would be OUT. This puts you in the position of buying (large) quantity you might need based on the description alone - which is why there are so few places I trust. Its just difficult sometimes

I was sooooo spoiled because Battery Clearinghouse had a ton or those rubber medical packs. I would order a couple, then a few days later a few more. Did that from September of last year to January of this year. Now, they are sold out. And I missed the 4 lots that Dan listed because I was slow (20 minutes) late to pull the trigger.
I am on a list to get notification if they get more of those cells in.
Not in a great rush, but wanted to get this done by the end of this year.