I just noticed these too. They are unprotected. Why are they so cheap (price for 2 cells)??? Aren't the CGR series the high current draw ones that usually have lower capacity? (Wait, I see these are CGR18650CG - CG at the end.)
-Garry
CGR series are just generally LiCoO2 cells. Just like NCR series have high draw cells (e.g. NCR18650E, NCR18650PD), so do CGR-series (CGR18650CH), but both series have classic cells (NCR18650 / NCR18650A / NCR18650B, CGR18650CH / CGR18650D / CGR18650E).
So what is their benefit? Higher current draw? Safer chemistry? Or is this a "budget" line of lower max current draw?
What is the max current draw of this cell? That spec sheet doesn't say much (and it's 6 years old).
-Garry
We will have to see when someone reviews or has experience using them. I’m thinking of buying them, so I’ll let all of you BFLs know how well it performs if I do.
It’s just a typical cell that’s used in laptop battery packs, considering that laptops usually have 6, 9, or even 12 of them - they have to be cheap.
For example, $4/cell = $48 of cells in a 12-cell pack, $8-cell (such as NCR18650B) = double of that. So laptop manufacturers aren’t chasing the highest capacities, they’re chasing best value - and that’s what Li-Ion cell manufacturers cater to, as laptop manufacturers are one of their biggest clients.
They’re pretty much same thing as Sanyo 2600mAh and Samsung 2600mAh cells, just from a different manufacturer.
I have some cgr18650ea batteries bought from this thread. This is how you identify the date code for these batteries LINK
It looks like these batteries dates are 7-23-2010
Dont know if this is good or bad. Are 2010 batteries if new are they just as good as 2012 batteries?
I have read that a typical Li-ion loses about 20% irreversible capacity a year. I have also seen that this doesn’t exactly hold true. The temperature that they are subjected to and voltage stored at determines a big part of their life expectancy when stored. If they where made in 2010 and stored with a proper voltage plus stored in a cool environment. I would guess to say at least 20% is lost in capacity (just a wild guess). There’s really no way of knowing without testing them. Too many variables that could influence capacity especially the stored temperature over that amount of time.
Don’t know. I think 2900mah lose cells started hitting the flashlight world in early 2009. Be hard to say with out date code.
Why not buy these http://www.fasttech.com/products/1420/10001980/1141103-panasonic-protected-ncr18650a-rechargeable-3100mah and use coupon code BLF for 5% off.
Or unprotected version http://www.fasttech.com/products/1420/10001980/1141105-panasonic-ncr18650a-rechargeable-3100mah-37v-18650.
At full charge.
At 50% charge only 3-5%
I made an overlay of the curves in the official datasheets:
The colored ones are the curves of the CGR18650E.
X-Axis is 0 - 2800 mAh
Y-Axis is 2.5 - 4.25V
Datasheet CGR18650E: http://photos.fedcoelectronics.com/PDF/1/Panasonic_LiIon_CGR18650E.pdf
Datasheet UR18650F(M): http://www.panasonic.com/industrial/includes/pdf/ACA4000CE289-UR18650F.pdf
Info here Lithium-ion battery - Wikipedia. Scroll down to disadvantages, this is not the only place that I have read this. There’s to many variables to get a estimated capacity left in a battery that has been stored for 2 years or more. One may have only a 10% loss and another 20% loss from the same batch. When a laptop battery pack refuses charging its usually only one battery that causes the hole pack to fail. The other batteries can have quite a bit of life left. They are from the same batch and subjected to the same temperature over there life span. Yet only one will cause the failure of the pack.
I’am not saying that these batteries are not good. I just saying there’s no way to no how good they are without someone buying a few and testing them. But I would expect they do have some losses. With a newer higher capacity cell being a few bucks more I can’t see myself buying the lottery ticket. 
They’re good and fresh cells.
These 2900mAh have NOT been out since 2009, they’re new, high current model that allows up to 10A discharge. They have only been in production since 2012.
This was taken from batteryuniversity “Although a battery should deliver 100 percent capacity during the first year of service, it is common to see lower than specified capacities, and shelf life may have contributed to this loss.” and with your chart you can see the temperature stored at plays a big role in that. I think these batteries have been stored not cycled or used. Apt323 stated that the date code was 7-23-2010, about 2.5 years.
This quote was also in the box above that you left out “Table 3: Estimated recoverable capacity when storing Li-ion for one year at various temperatures. Elevated temperature hastens capacity loss. The capacity cannot be restored. Not all Li-ion systems behave the same.” As I stated early I have seen this 20% not hold true. I think the 20% statement I have read is from normally usage, cycling the cell. The more cycles the lower the capacity but these are supposedly stored cells.
My point was that there’s really no way to know what conditions these batteries have been stored in voltage wise or temperature.
Ya, you got me there shadowww. :bigsmile:
Was thinking of the old AW cells. Missed the PD.
AW 2900mAh batteries use Panasonic NCR18650 cell, which has later got updated with NCR18650A (3100mAh) and NCR18650B (3400mAh) 
Yep, that’s them came about early 2009. I missed seeing the PD on the cells at fasttech. Went by the capacity even though I had reviewed the thread less than a week ago where they were announced at fasttech. Fasttech - interesting new products - Flashlights, chargers, batteries and DIY and knives - please no discussions.
A year or so ago the whole forum bought Rev Jim panasonic batteries for under 2$ each...They were old ...and are still really good .
The numbers on the batteries are
D
8517
I think the 20% a year business is crazy talk
it hasn't been my experiance at all .
I do agree Boaz,
It does have a lot of variables to consider.
For instance me and you both buy the same battery at the same time. I use and deplete mine daily over discharging it slightly with a discharge load of 4amps. I leave mine in my car sometimes during the summer. I charge them with a charger that’s constantly over charging them not following the proper algorithm with a charge rate of 1.5C. Drop it on the floor a couple a times a week. In a year I may have 365 cycles
You on the other hand charge yours on a proper charger following the proper algorithm with a charge rate of .7C. You keep yours in a controlled temp room of 70. You never ever drop yours. You use it sparingly with only a 1amp discharge load over a month. Before the battery reaches 3.5v at rest you pull it and charge it to only 4.10v. In a year you may have 12 cycles.
I did everything that causes a loss in capacity and life of the cell over a year, you did ever thing to extend capacity and life over a year. Same battery but two different environments.
I was assuming 20% was a lion cell be subjected to several cycles over a year and maybe some flaws in proper usage (a typical user). From my experiences I would say that 20% doesn’t apply to my limited use cells. That 20% statement is just something I read more than once on the net. But if you where a heavy user with very bad cell care I guess it would be feasible to reach that number quite easily.