Cycle life tests of High Energy density cylindrical cells

[Pajda]

Small update

Update:
- added more cycles at 90% and 100%.
- Samsung "58E" begins to die after 600 cycles at 100% DoD a similar fate is waiting for the Samsung 53G1. I would recommend to wait for the "2" generation, which is common rule in Samsung production line.

More to come:
Vapcell F63, N41 and finally LG M52VT are on the way to me.

 

[freesty]

oh yeah, the lg m52vt

 

[ediskrad]

Greetings! I previously wrote a review on the elements of FEB 6000mah (vapcell f60). I built a 16s14p battery. At a constant load of 60 amps, the battery overheated. In the end, I still put the battery on my electric bike. I'm taking 80 amps off it at its peak and there wasn't any overheating, not even close) I have gear motor wheels in all-wheel drive and it is problematic to keep almost 5 kW of power on them at all times ..) Although I drive extremely aggressively. Initially, the battery is assembled on FEB 6000 mAh cells. I'm currently building the same one on a Vapcell f60. When analyzing FEB and Vapcell, I saw the difference. Apparently, they produce batches for Vapcell separately on FEB, because Vapcell has clearly better characteristics and they do not heat up so much

 

[ediskrad]

Small update

Update:
- updated 5300mAh+ charts 100% and 90% DoD

Vapcell F60 died after 800 cycles at 100% (with 2.8V cut-off), when cycled down to 2.5V it was around 700 cycles.

Great news! Thank you for your work!

 

[BatteryMooch]

Greetings! I previously wrote a review on the elements of FEB 6000mah (vapcell f60). I built a 16s14p battery. At a constant load of 60 amps, the battery overheated. In the end, I still put the battery on my electric bike. I'm taking 80 amps off it at its peak and there wasn't any overheating, not even close) I have gear motor wheels in all-wheel drive and it is problematic to keep almost 5 kW of power on them at all times ..) Although I drive extremely aggressively. Initially, the battery is assembled on FEB 6000 mAh cells. I'm currently building the same one on a Vapcell f60. When analyzing FEB and Vapcell, I saw the difference. Apparently, they produce batches for Vapcell separately on FEB, because Vapcell has clearly better characteristics and they do not heat up so much

Thank you for posting your experiences with these cells!

It’s rare to have the same cell, even of different grades, perform so differently like that. And FEB would never sell “better” cells to a company as small as Vapcell instead of to their huge commercial customers (buying millions of cells a year). If anything, Vapcell would get the same cells or even a lower grade since they wouldn’t be a prime customer for the top grade cells.

I know it was the rumor that was going around but has it actually been confirmed that the F60 uses the FEB 6Ah cell? Have you compared the cells (with wraps off) and they are identical in appearance, even when using a magnifier?

 

[Pajda]

This is a good question. I still have no confirmation who is the manufacturer of the F60 series from Vapcell. It was my speculation that FEB might be the manufacturer, because at that time I had no information about any other manufacturer that had 6000 mAh cells in their lineup.
Also, to this day I have not been able to obtain samples of the original FEB cells for comparison. One of the distributors just told me that they have already removed FEB cells from their stock because customers complained about their quality. Since Vapcell now has F63 and FEB doesn't have anything like that on the site, I would be more inclined to think that Vapcell is getting cells from another manufacturer.

 

[BlueSwordM]

This is a good question. I still have no confirmation who is the manufacturer of the F60 series from Vapcell. It was my speculation that FEB might be the manufacturer, because at that time I had no information about any other manufacturer that had 6000 mAh cells in their lineup.
Also, to this day I have not been able to obtain samples of the original FEB cells for comparison. One of the distributors just told me that they have already removed FEB cells from their stock because customers complained about their quality. Since Vapcell now has F63 and FEB doesn't have anything like that on the site, I would be more inclined to think that Vapcell is getting cells from another manufacturer.

Another supplier of the FEB 6000mAh cell did tell me that FEB might have done some naughty things around the cell's release regarding battery grades.

Apparently, most of those cells on the market are actually B-grade currently, and only recently have true A-grade cells been a thing; FEB/FST's definition of A-grade for this cell might have changed with time to increase valuable yields.

 

[BatteryMooch]

Another supplier of the FEB 6000mAh cell did tell me that FEB might have done some naughty things around the cell's release regarding battery grades.

I’d be stunned if that was true as it would be ”corporate suicide”. Their large customers would drop them quickly and buy from another manufacturer rather than deal with the nightmare of changing cell performance…IMHO.

But in the cutthroat world that is cell manufacturing, especially when China gets involved, I guess we can never say never.

Apparently, most of those cells on the market are actually B-grade currently, and only recently have true A-grade cells been a thing; FEB/FST's definition of A-grade for this cell might have changed with time to increase valuable yields.

I completely agree that many, even most, of the cells we buy are likely not top grade. At least until demand drops for the top grade cells or the big customers start selling off excess top grade inventory.

We are in the terrible situation of only being able to get info via rumors and (almost) never having access to known top grade cells to use as a performance reference when testing. Incredibly frustrating!

 

[BlueSwordM]

I’d be stunned if that was true as it would be ”corporate suicide”. Their large customers would drop them quickly and buy from another manufacturer rather than deal with the nightmare of changing cell performance…IMHO.

But in the cutthroat world that is cell manufacturing, especially when China gets involved, I guess we can never say never.


I completely agree that many, even most, of the cells we buy are likely not top grade. At least until demand drops for the top grade cells or the big customers start selling off excess top grade inventory.

We are in the terrible situation of only being able to get info via rumors and (almost) never having access to known top grade cells to use as a performance reference when testing. Incredibly frustrating!

Of course, but there's the corporations' market, and then there's the small business market.

I wouldn't be surprised "smaller" companies like FEB prioritize the highest grade cells for those who order 500k+ cells to millions of cells every year, and then we got the "scraps" for a while.

But yeah, this kind of informed speculation is killing.

If I was rich, I'd just pose as a large customer and try to extract blood from the stones, but even then, I doubt I'd get the answers we want.

In the meantime, I can now order EVE 50PLs
Perfect cold weather cells, although they're 2x more expensive than 50Es.

 

[riba2233]

Of course, but there's the corporations' market, and then there's the small business market.

I wouldn't be surprised "smaller" companies like FEB prioritize the highest grade cells for those who order 500k+ cells to millions of cells every year, and then we got the "scraps" for a while.

But yeah, this kind of informed speculation is killing.

If I was rich, I'd just pose as a large customer and try to extract blood from the stones, but even then, I doubt I'd get the answers we want.

In the meantime, I can now order EVE 50PLs
Perfect cold weather cells, although they're 2x more expensive than 50Es.

50PL where, I need to know

 

[BlueSwordM]

50PL where, I need to know

Something something Alibaba supplier sent me a message that they're now available if I'm willing to pay 15-20% extra than the BAK 45Ds I've been eyeing.

 

[riba2233]

Something something Alibaba supplier send me a message that they're now available if I'm willing to pay 15-20% extra than the BAK 45Ds I've been eyeing.

Awesome, I hope they pop up on nkon soon. I need 40 pcs for some battery packs. Shipping from China would probably make them too expensive.

 

[ediskrad]

The person who cooked the battery cut both elements. The element from Vapcell is different from FEB. Despite the fact that I contacted Vapcell directly and asked them about the manufacturer of the elements. They said about FEB. And about the fact that the grade was B... I highly doubt it. I agree that the company would have buried its reputation, because there is high competition in the market and such stupid steps would have hurt the company.

 

[Pajda]

Small update

Update:
- added more cycles at 90% and 100%.
- Lishen 58SK finished 1,000 cycles in both DoD tests with outstanding results. I will continue with the test up to 2,000 cycles or sudden death.