Has anyone tried these yet? Will they actually fit into a Mag tube? Are they worth the price?
Thank you
Thank you
BatterySpace D & F LiFePO cells?
- Thread starter BigusLightus
- Start date
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JimmyM
Flashlight Enthusiast
These are interesting. D size "A123"s. Hmmmmmmm.
I just ordered four. I'm hoping to sqeeze all four into a 6D Mag with AW switch, FM MOP, Boro, and a 64625 lamp. In the future I might put an FM 3" head on to help with cooling cause this sucker gets really hot. Currently using two BatteriesWholesale 4Ah MagCharger style sticks. They dim too easily from the 2.5C drain and don't last long enough. I expect my new project will be much lighter and brighter.
mudman cj
Flashlight Enthusiast
That sounds like a great light! I have a similar one using 4 of the original D size Li-ion cells from a few years ago. It screams along with an AWR hotdriver and some tailcap resistors to keep from blowing the driver by asking too much of it. Almost 3000 lumens for 30 minutes out of a 4D mag. But yours will be a bit safer than mine. Couldn't you fit yours into a 4D? Why are you using a 6D host if you don't mind my asking?
But yours will be a bit safer than mine. Couldn't you fit yours into a 4D? Why are you using a 6D host if you don't mind my asking?
Hi Mudman,
I could have used the LiFePO4 D cells but wanted the max runtime. Thus I'm using the F size cells (1.5 D cells in size). The Ah rating is a little better than the same LiFePO4 D cells. I'm hoping that four F cells will fit into a 6D Mag.
At nominal 3.2 x 4 = 12.8 Volts my 64625 lamp should really pump out the photons.:twothumbs
I could have used the LiFePO4 D cells but wanted the max runtime. Thus I'm using the F size cells (1.5 D cells in size). The Ah rating is a little better than the same LiFePO4 D cells. I'm hoping that four F cells will fit into a 6D Mag.
At nominal 3.2 x 4 = 12.8 Volts my 64625 lamp should really pump out the photons.:twothumbs
JimmyM
Flashlight Enthusiast
the "F"s are 90mm long. 90mm x 4 = 360mm. The length of 6 normal D cells.
You should be fine.
Keep in mind though. These cells are 3.6-3.8V of the charger. So that's 14.4-15.2V.
The 64625 is a sensitive bulb. It could very well instaflash on 4 freshly charged F cells. Especially since these won't sag all that much. Smaller cells would sag almost instantly to 3.3V each.
mudman cj
Flashlight Enthusiast
Ah yes, you did mention the F cells didn't you.
And JimmyM is right, the 64625 is likely to instaflash with this setup. You may find success by adding tailcap resistors as are used in my light to drop some voltage, but then that will also reduce output slightly (though it doesn't in my case because I am starting with 14.4V after sagging and need to drop about a volt so the regulator can handle the rest). A more elegant solution would be to use an NTC (possibly also in combination with a resistor). Look up posts by Northern Lights for more info on the use of NTCs.
And JimmyM is right, the 64625 is likely to instaflash with this setup. You may find success by adding tailcap resistors as are used in my light to drop some voltage, but then that will also reduce output slightly (though it doesn't in my case because I am starting with 14.4V after sagging and need to drop about a volt so the regulator can handle the rest). A more elegant solution would be to use an NTC (possibly also in combination with a resistor). Look up posts by Northern Lights for more info on the use of NTCs.
2xTrinity
Flashlight Enthusiast
I had the 64625 instaflash using 4 LiIon D-Cells, even with a PWM soft start, so I had to switch to 64623 (which is somewhat underdriven, but still a lot of lumens and just as capable of burning things).
Those are are 16.4V under no load fresh. However, I suspect that the LiFePO4s will have a lot less internal resistance than my LiIon D-Cells (the kaidomain 5AH types), so you will probably still have the same risk of instaflashing, especially if you don't have some form of soft start.
Those are are 16.4V under no load fresh. However, I suspect that the LiFePO4s will have a lot less internal resistance than my LiIon D-Cells (the kaidomain 5AH types), so you will probably still have the same risk of instaflashing, especially if you don't have some form of soft start.
