Efest state a diameter of 26.26mm for their Purple 26500 IMR batteries. I need to know the inside diameter of the battery tube of a Mag C-cell as I don’t want to buy the Efest only to find they’re too fat and I don’t have a C-cell Mag to check.
I’m pretty sure the red Efest (@ 25.56mm) will fit but they’re hard to get locally whereas I can easily get my mits on the purple variety.
Are there any other 26500 size LiIon batteries worth considering?
No they wont fit.
the only ones that fit are sold by mtnelectronics
http://www.mtnelectronics.com/index.php?route=product/product&path=59_108&product_id=399
I have 4 IMR Kinoko 26500’s that also fit but I don’t know where to buy them and they don’t do really good at 5A or more.
bigC
Yes - they’re the red Efest I mentioned - pricey buggers - anyone know where I can get them with free delivery to the UK?
Efest 26500 3000mAh IMR Battery
Flat top Efest IMR 26500 3000mah 3.7v LiMn Rechargeable Battery
Unprotected, flat top.
This is a great cell for Maglite Mods, or in other places where you want to replace “C” sized cells with a lithium cell for driver/LED upgrades. This cell is about the same length as a standard “C” cell, and is also slightly narrower than most 26650s so that it can fit into most “C” sized tubes, which are often too tight for a 26650 cell.
Specifications:
Diameter: 25.6mm
Length: 49.4mm
Nominal Capacity: 3000mAh
Maximum Charge Voltage: 4.2v
Efest 26500 3000Mah with 48A discharging current purple flat top high drain battery
Brand: Efest Model: 26500V1
With 48A discharging current
Capacity:3000mah
Material: LiMn
Positive Pole: Flat top
Size:26.26(D)*50.07(L)mm
I wonder how many amps those calipers pull dead shorting that battery. :bigsmile: 
I jest, surely they were smart enough to put some tape over the contacts…….
Also remember that fitment will depend on what kind of Maglite yu are trying to fot the cell into. The old Mags without a C in the serial number generally have a larger inside diameter than the newer Mags with a C in the serial number. So if a given cell won’t fit in a new Mag, it MIGHT fit in an old Mag.
yes older C mags are a bit bigger, but they are not made since 90s iirc. not so easy to find one.
Hi all,
I just placed my order for the IMR Efest 26500’s that Mtnelectronics sells.
Both of mine are 25.6mm and do not fit my two C size Maglites.
I do have 2 Kinoko IMR 26500’s that do fit and those are 25.5mm.
Crazy how just 1mm makes them fit
Would you happen to own a DST (Defiant Super Thrower)? Im curious if your Kinoko’s would fit.
I would like to know this as well.
The 3C Defiant with big bezel I have purchased several from HomeDepot. They all fit even my IMR 26650’s, heck even the Keeppower protected 26650’s fit in those Defiant 3C hosts.
bigC
Thanks BigC. My King Kong 26650’s are too wide to fit the DST, so I might need to check out the other cells you mentioned.
I am looking at them for POP lites. I have only a stainless C POP at this time, a P673, which is not one of those I am considering the cell for.
An included cell measures 25.7mm and has around one mm. of clearance in the battery tube. The inside jaws of my caliper are too short to measure the ID directly.
26.7 - 26.26mm = 0.44. So I should have half a mm. of clearance if the POP lite models are all the same and I estimated accurately.
Added: Richard’s listing says:
Diameter: 25.6mm
Length: 49.4mm
That is the same as the included cells with the P673.
My alkaline cells measure 25.3mm.
It’s easy to make them fit, just buy a small brake hone and a drill, a 30 minute job…
Good. If I get a light and cells that don’t fit, I can buy a hone and make it fit.
What is the best source, now that Mtn. is out of the red ones?
According to http://lygte-info.dk/review/batteries2012/Efest%20IMR26500%203000mAh%20(Blue)%20UK.html, the blue Efests are not high drain cells, even though they say IMR on them.
Here is the red one: http://www.mister-e-liquid.com/efest-imr-26500-3000mah-battery/.
Can’t comment on a battery source, as I’d like to know that information as well. I was working on a Mag build for XHP50/XHP70, but now that Convoy has released the L6 I can’t decide if I should build or just buy. Was looking for for 26500’s myself and found this thread.
On the brake hone I do have a suggestion however, if you decide to go that route be sure to use fluid and finish with the higher grit stones. I had the wrapper get chewed up on some 2nd gen Eneloop’s a couple of years back because of a rough interior finish after honing. 
-Michael
Thanks.