18650 Battery Store Legit? Will not answer the phone.

[toms]

Everyone thinking that because cells reach capacity and have low IR so they will be OK even if they failed initial QA tests is missing the point.

The first test after the initial charge cycle is a scanning electron microscope test that examines the SEI for initial formation.

If formation isn’t uniform the cell is rejected, and the remaining SEI formation regime isn’t done. You are gambling on lifespan that will be significantly shorter due to poor SEI formation. I wouldn’t pay more than 1/3 the price of a good cell for one that has failed QA. My experience is that they will likely have about 1/3 the lifespan.

Cell brokers have been selling factory rejects since 2008 with Thundersky’s. The sellers are getting better at making the rejects look better, i see no evidence they are making them last longer.

It’s a shame that even resellers can’t trust the cell brokers that distribute reject cells. They often claim everything they sell is “Grade A +++”

 

[Kornbread]

Everyone thinking that because cells reach capacity and have low IR so they will be OK even if they failed initial QA tests is missing the point.

The first test after the initial charge cycle is a scanning electron microscope test that examines the SEI for initial formation.

If formation isn’t uniform the cell is rejected, and the remaining SEI formation regime isn’t done. You are gambling on lifespan that will be significantly shorter due to poor SEI formation. I wouldn’t pay more than 1/3 the price of a good cell for one that has failed QA. My experience is that they will likely have about 1/3 the lifespan.

Cell brokers have been selling factory rejects since 2008 with Thundersky’s. The sellers are getting better at making the rejects look better, i see no evidence they are making them last longer.

It’s a shame that even resellers can’t trust the cell brokers that distribute reject cells. They often claim everything they sell is “Grade A +++”

Do you have some good reading material on sei formation?

 

[toms]

Do you have some good reading material on sei formation?

Nope - i’m more of an audio type person, all i know about LiFePO4 came directly from a manufacturer. I’ve tried previously to match up what i’ve been told with various online white papers, but what you find online is usually written by grad students as part of their studies and is lacking in specifics.

The basic explanation is if you start off the initial charge regime with too low current, you will get dendrite seeding. If you have too high current you will end up with a porous SEI layer.

I doubt you’ll get the exact procedure, but typically a cell will be need to be charged several times before the SEI is stable, and until that point the anode will be susceptible to dendrite seeding.

That is what will shorten the lifespan of a cell that has failed QA due to SEM anomaly. Which is why if someone is offering a cell that has passed manufacturer QA, they should be able to prove that to you.

 

[sunshine_eggo]

Nope - i’m more of an audio type person, all i know about LiFePO4 came directly from a manufacturer. I’ve tried previously to match up what i’ve been told with various online white papers, but what you find online is usually written by grad students as part of their studies and is lacking in specifics.

The basic explanation is if you start off the initial charge regime with too low current, you will get dendrite seeding. If you have too high current you will end up with a porous SEI layer.

got an approximate C rate or range?

 

[toms]

got an approximate C rate or range?

Initial charge around 0.2C to 3.65V. Cell is then scanned to check anode condition.
Four or five more charges ramping down to 0.05C.

Keep in mind the charge is terminated immediately the 3.65V is achieved. The cell never stays at that voltage.

 

[timselectric]

Everyone is going off the deep end with all of this.
The first thing that you have to understand is that every single cell that we are buying are rejects.
Otherwise, they would be installed into Chinese EV's.
But being rejects is not a bad thing. (For us)
It allows us to get great (for us) cells for a great price.
They're not good enough for EV's, but they're perfectly wonderful for solar storage.
That said, there are many levels of rejection.
And it's important to find the better quality rejects.
Buy paying attention to what others say about the cells that they purchased. You can make informed decisions about where to buy your own cells.
One markets trash, is another markets treasure.

 

[sunshine_eggo]

Initial charge around 0.2C to 3.65V. Cell is then scanned to check anode condition.
Four or five more charges ramping down to 0.05C.

Keep in mind the charge is terminated immediately the 3.65V is achieved. The cell never stays at that voltage.

So the manufacturer's 0.05C tail current at 3.65V is not adhered to? It's 0.2C and stop?

We've all seen bookcase-like banks of test rigs for these prismatic cells where many hundreds of cells can be tested simultaneously. Are we to assume the manufacturers are leaving this critical process, that's not documented, to the customers to accomplish instead of doing it themselves?

 

[toms]

So the manufacturer's 0.05C tail current at 3.65V is not adhered to? It's 0.2C and stop?

We've all seen bookcase-like banks of test rigs for these prismatic cells where many hundreds of cells can be tested simultaneously. Are we to assume the manufacturers are leaving this critical process, that's not documented, to the customers to accomplish instead of doing it themselves?

If you are buying cells that have failed QA for initial SEI formation, then yes - you have to do the best you can to finish the formation process.

The manufacturer isn’t interested, they have already rejected the cell.

If you are truly buying a cell that had passed QA, then it doesn’t matter how you charge as long as you don’t drop below 0.05C @ 3.65V.

 

[sunsurfer]

Initial charge around 0.2C to 3.65V. Cell is then scanned to check anode condition.
Four or five more charges ramping down to 0.05C.

Keep in mind the charge is terminated immediately the 3.65V is achieved. The cell never stays at that voltage.

I'm curious what is involved with "scanning" a cell. Are they doing a Spectro (EIS) type scan?

 

[A.Justice]

They are completely legitimate in my opinion. I vape, and that's where all of my 18650s come from, I've never got a bad cell from them either.

 

[42OhmsPA]

They are completely legitimate in my opinion. I vape, and that's where all of my 18650s come from, I've never got a bad cell from them either.

Well they are the 18650 battery store. ?

Now you gave me an idea, wiring up my spare 305ah prismatic to one of my dry herb vapes ?

I'd order from 18650, again, with 0 hesitation.

 

[sunshine_eggo]

Well they are the 18650 battery store. ?

Now you gave me an idea, wiring up my spare 305ah prismatic to one of my dry herb vapes ?

I'd order from 18650, again, with 0 hesitation.

Want to reiterate my earlier comments...

I wouldn't hesitate to buy from them either... as long as I'm not building an EV battery.

The $75 Envision cells are back, and I want 8 REALLY BAD! $750 DELIVERED.

 

[timselectric]

All of my cells have come from them. And so will the next 144.
(Also, not building an EV)

 

[42OhmsPA]

Want to reiterate my earlier comments...

I wouldn't hesitate to buy from them either... as long as I'm not building an EV battery.

The $75 Envision cells are back, and I want 8 REALLY BAD! $750 DELIVERED.

That was quick.

 

[SparkyJJO]

That was quick.
View attachment 188573

You know who to blame.

 

[G00SE]

Damn it. I’ve check their site twice today and they were still sold out both times.

 

[Alkaline]

Everyone is going off the deep end with all of this.
The first thing that you have to understand is that every single cell that we are buying are rejects.

Looks like you have been going to the grade B Kool-Aid stand and its starting to mess with your head.

This is the certification for the LF280K and its listed for UL1973 which is NOT rated for use in a vehicle so anyone claiming the 280K sold by 18650 are failed EV cells is an idiot: https://www.sunfunkits.com/MediaStorage/Product/Documents/Document/55_20231219082553974.pdf

This is the certification for the LF304 and its listed for UL2580 WHICH IS AN EV rated cell designed to be used in vehicles:https://www.sunfunkits.com/MediaStorage/Product/Documents/Document/55_20231220080717296.pdf now you could potentially say the 304 cells sold by 18650 battery store are failed EV cells, but you can only make that claim if you have proof that they are some how altered or don't have test reports (which I[m sure they do but hoping they start providing them to stop this bs rumor going around).

I see this thread as nothing more than attempt by the grade B mob to attempt to change the narrative to do what they have always wanted to do, muddy the waters to make it seem like there is no difference between grades: Cells with intact unaltered qr codes & test reports, Sanded off and re-lasered grade, Grade B or, Fraud grade.

18650battery store is legit, it was one of the first stores in the USA to offer cells at similar prices to Alibaba, it forced other usa vendors to lower prices and is established. Haters are just jealous because there little fly-by-night operation ghetto ebay / amazon store can't compete with them.

Sfk was the piñata for a while, you just watch, they are gonna start going after Ezeal and Batteryhookup soon too they are just looking for a "in" so they can inject there garabage "no difference between grade a or b bs"

Don't fall for it. I built batteries with both. Grade b sucks and in todays pricing extremely overpriced at near 85%-90% of the cost of grade A.

 

[G00SE]

@Alkaline is your position that 280k are made simply for us to buy as individual cells to make our own ESS?

 

[Sam Cho TX]

Looks like you have been going to the grade B Kool-Aid stand and its starting to mess with your head.

This is the certification for the LF280K and its listed for UL1973 which is NOT rated for use in a vehicle so anyone claiming the 280K sold by 18650 are failed EV cells is an idiot: https://www.sunfunkits.com/MediaStorage/Product/Documents/Document/55_20231219082553974.pdf

This is the certification for the LF304 and its listed for UL2580 WHICH IS AN EV rated cell designed to be used in vehicles:https://www.sunfunkits.com/MediaStorage/Product/Documents/Document/55_20231220080717296.pdf now you could potentially say the 304 cells sold by 18650 battery store are failed EV cells, but you can only make that claim if you have proof that they are some how altered or don't have test reports (which I[m sure they do but hoping they start providing them to stop this bs rumor going around).

I see this thread as nothing more than attempt by the grade B mob to attempt to change the narrative to do what they have always wanted to do, muddy the waters to make it seem like there is no difference between grades: Cells with intact unaltered qr codes & test reports, Sanded off and re-lasered grade, Grade B or, Fraud grade.

18650battery store is legit, it was one of the first stores in the USA to offer cells at similar prices to Alibaba, it forced other usa vendors to lower prices and is established. Haters are just jealous because there little fly-by-night operation ghetto ebay / amazon store can't compete with them.

Sfk was the piñata for a while, you just watch, they are gonna start going after Ezeal and Batteryhookup soon too they are just looking for a "in" so they can inject there garabage "no difference between grade a or b bs"

Don't fall for it. I built batteries with both. Grade b sucks and in todays pricing extremely overpriced at near 85%-90% of the cost of grade A.

100% agree, a lot of forum people tell you its OK to grade B its just as good. TOTAL BS I bought 4 grade B cells and 1 was a turd, I refuse to believe I was so unlucky. No reality is most people never even test and just assume its all good and just ignore the truth.

 

[Alkaline]

@Alkaline is your position that 280k are made simply for us to buy as individual cells to make our own ESS?

The 280K is an ESS cell designed to make packs, you could make one yourself or get one assembled by a manufacturer like eg4 or fortress power (who use eve cells).

Energy Storage System Testing and Certification

You can leverage our expertise with safety testing and certification for large energy storage systems.

www.ul.com

So based on this it would make sense its a better choice for people making cells.

I think 304 makes more sense if you need the most amount of power in the smallest space.

ALSO ABYC requires UL1973 cells/batteries now so I don't think you can get that with the 304 as they are not recognizing UL 2580.