Thanks for testing!
As of now it seems to be the cell with the least voltage sag in the 5A range. I used your comparator and paired it with all of the usual high drain suspects - this one prevails.
As a result I bought 2 of these from FT. I have by no means the adequate equipment for proper testing (just a humble imax B6) but my quick and dirty test is to take all new cells, put them unter 1A load and measure the voltage with a DMM directly at the cells:
Examples:
Sanyo 2600 FM: 4.09V
Samsung 25R: 4.15V
Tensai 4500: 4.13V
MNKE 3500: 4.15V
Vappower 4200: 4.17V
At least that gives me a hint that I got some good stuff.
So the Vappower 4200 is very good for single cell / single emitter lights in 26650 format like the HD2010 and the UF-F13.
Where are these made? China? Nothing written on the battery.
EDIT: I think I just found my answer on a Dealer website:
Vappower IMR 26650 4200 mAh
New Lower Price
These high drain batteries come from a collaboration of engineers from the Canadian battery company, MOLI, and a factory in China. Produced on automated machines.
IT is hard to find,the few that I did were a few dollars more than where I got mine on Ebay from a reputable Dealer who i bought batteries before. I got it today w/ my EC60vn coming next week!
Not bad batteries but, as happens with many other random overpriced rewraps, the LiitoKala 26650-50As will smoke these with ease in every aspect. In the history of the 26650 li-ion cells, the Liitos are the messiah of a new age, combining good capacity, good power delivery and great price. 'Nuff said.
I have a group of these batteries and you are correct, but I use these only in my single cell lights. They are a good battery at a good price. I hope to see some test results from HJK.
It can be clearly seen these cells have an internal resistance of about 26mΩ, easily deduced from the discharge graph.
I've grossly home-made tested the IR of six LiitoKala 26650As: less than 23mΩ. I say grossly because I used a millivolt multimeter but with a load just a tad above 1A, registering a delta of 23mV.
My figure is consistent with other various results of users in the forum.
They are not as good why would you want them!!! lol!
I got 2 for $19.99 w/ free shipping. r-sales on Ebay.
At least $4 cheaper, USA dealer,free shipping,got them in 4 days. I RARELY order from China,the wait is NOT worth it, even when you can save a few dollars,obviously for these batteries that[saving money] is not even the case!
I just received my Acebeam EC50 II, and I notice that the Turbo mode only works with an almost fresh-off-the-charger battery (using the supplied Acebeam 26650). So I started looking at other 26650s, and this Vappower one seems to be one of the best, along with the Efest purple 3D 4200 mAh.
Has anyone seen a voltage graph of the LiitoKala 26650-50A? Is the LiitoKala an IMR? If not, I would expect that its voltage would sag more than the Vappower and Efest IMRs under higher loads.