I need to get some 18650 batteries. I found those batteries listed on the new products section at Fasttech but could not find any review on them. Are they good batteries for the price? please advice.
Many thanks
At these price…
New? Or from battery pack?
Panasonic Protected NCR18650B $19.01 2-pack
Panasonic Protected NCR18650A $15.37 2-pack
Are there better prices than these? 
I saw the Panasonic CGR18650E today as well. It seems to be good cells from the datasheet: http://photos.fedcoelectronics.com/PDF/1/Panasonic_LiIon_CGR18650E.pdf
Even though I haven’t used one yet, I’m pretty sure they are genuine and good cells because they’re from PANASONIC and not any of the **fire brands that generally have overstated capacities. I’m probably going to buy one to test
Hm, these might be even better than 2600mAh Sanyo’s (UR18650FM), seeing how 2250mAh Panasonic (CGR18650CG) outperform 2250mAh Sanyo (UR18650A). And they’re cheaper, too. Interesting.
Hopefully HKJ will test these.
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.