Wow...looks real good at 3A too at 4.2AH and i suppose your room is quite cool too? If running at 1A / medium and the cell is kept warm (well my country is always warm heh), probably get close to my results. I digged it down to about 2.7-2.8V too and the knee might extend a bit and not fall off as sharp as at 3A.
The MKNE IMR doesn't even flinch and experience any change in capacity at 3A. I got ard the same numbers as you at 1A.
68F/20C. Since I intend on using these in the JM07 PRO, this is really highest amperage test I needed to see, but for the sake of science I’ll push them harder tomorrow.
EDIT: Another interesting thing to think about is the additional POWER of the 26650. Its not just the Ah, it is the watt hours. We've got 3.1Ah 18650s and the 26650 only bumps it up over 4Ah, BUT if you take voltage into account, the story is a little different.
Now I'm making up my own rules a bit, but If I compare my best Panasonic 3100 to my MIDDLE KK 26650 at 3A and cut it off at 3v the power is 8.90Wh vs 14.82 Wh. That means in that particular example, the 26650 has 66% more power than the 18650. If the cut-off was set lower the 3100 would gain a little on the 26650, but I think 3v is reasonable. The advantage is also very similar over a Sanyo 2600.
Well, temperature plays a small but noticeable part. If you are discharging a JM07 at 20 deg C ambient @ 3A, the cell would definitely discharge at at least 50 deg C after 10 minutes. :) My JM07 does 2.6A, btw.
If you look at all Sanyo official discharge graphs for Li-ion batteries you will notice that at 40 Celsius the result capacity is larger than at 20 Celsius.
That is good to know, I thought ( I thought wrong) at high temps they would work worse than at at 20º for example as normally heat in electricity is related to losses.
20 amps, the springs, switch and components would smoke first probably...heh.
Actually > 5A it is already not in the realm of budget lights already, but stuff like Elektrolumens, Lambda, HID searchlights with relays built in for switching. (my HID has a 10A rated relay in it)