It is my understanding that the Cree MT-G2 needs more amps than the 2.4 amps that the link you provided listed.
Good question CD. I have asked myself that question before.
I don’t know; that doesn’t make any sense. The MT-G2 forward voltage is very close to 2xXPL in series at ~2.5A, so I don’t see how the driver would even know the difference.
Ripple in the driver gives issues with all the dies? Idk
Would not this driver need batteries in series to drive the output current of 2.4 amp?
I know of only one Cree MT-G2 single cell flashlight that is in production.
What voltage requirements would be needed?
It is a 6 volt LED
“CREE MT-G2 Q0 on Noctigon MT-G20 MCPCB
6V Version
Approximate light output:
920-970 lumens @ 1100mA 25°C
2116-2232 lumens @ 3000mA 25°C”
None of that really answers the question…
Maybe we need to ask Mr. Hank Wang himself.
Thank you, but the original inquiry from my understanding was asking why the mentioned driver was not compatible with a single cell; did I misread this question?
The driver specs are:
“*Suitable for 1-2-3 18650, 16340 or 18350
*Input voltage: 3-16V
*Drives LEDs up 6.6V
*Output current 2.4A”
runs off 1, 2 or 3 cells. But the specs also state “Not suitable for MT-G2 LED.”
So, seems like the driver can’t deliver the full amps to make the MT-G2 run a maximum brightness. Or am I missing something??
Thank you MtnDon the specs are in agreement with your post. It seems the specs indicate all but larger batteries than 18650, 16340, or 18350 are suitable with the exception of a Cree MT-G2; does this imply that a 26650 battery would not work with this driver?
This turning out to be an educational question. 
This driver should still run the MTG2 at 80%? I am sure you can mod it for some extra power?
The driver can’t tell if the cell is 16, 18, 26 mm or larger in diameter. It can only sense the voltage. My guess is that the specs reflect the minimum size (capacity) cells they recommend.
Thank you again for your answer.
I have a Fenix PD40 a 26650 single battery light running a Cree MT-G2; is this light using a special driver? I have not seen any other single cell light using a MT-G2; is this true?
What about this?
http://www.kaidomain.com/p/S025264.FX35-22mm-3V-4_5V-2_5A-5-Mode-Boost-Driver-Circuit-Board-for-Cree-MT-G2
+1
Thank you.
I wonder if any one has tested that driver yet? You still have the issue that the MTG2 is under driven.
This may be the driver or a similar driver the Fenix PD40 uses. It has a 1600 lumen burst and four other modes. From my reading the Cree MT-G2 can be driven harder, but for my usage the PD40 does a fine job.