Is this normal behaviour for 10440 cells?

[hazna]

I have a couple of ultrafire 10440 batteries which I run on my fenix LOD Q4. When I run these batteries on high, it starts of very bright but after ~30 secs, it starts dimming down to the level of medium (or lower). This happens on a fully charged battery, and happens with all 3 of my batteries. Some batteries seem to stay bright slightly longer than others.

I was wondering is this behaviour normal for running 10440 on the LOD Q4? Is overheating protection kicking in and reducing the brightness? Or do I have 3 defective cells. It would not surprise me if I have damaged the cells. My previous charger TR-001 isn't really suited for 10440, even though the packaging claims to. I have ordered a cheap multimeter to monitor my cells, but it is still on the way.

 

[Marduke]

10440 cells in the L0D don't last very long, life cycle wise. So I would expect the cells to simply be dead and dying.

 

[mudman cj]

I am curious about the brand of the cells too.

 

[Marduke]

He said ultrafire...

 

[DM51]

Ultrafire :green:

 

[45/70]

hazna, from the labeled charge rate, and what some have said is the actual rate that the TrustFire TR-001 charger charges cells at, it can be detrmined that this charger, at least initially, charges at a rate of well over 1C for a 10440 LiCO cell. The charge rate should not exceed 1C, or about 300 mA. It probably should be lower as, in my experience with UltraFire 10440 cells, they are actually no where near even 300 mAh (my UltraFire 10440's say "600 mAh" on them:laughing, more like 250 mAh and that is being optimistic. You could very well have damaged your cells with this charger.

In addition to the charger issue, I will say that in my LiteFlux LF-2 (which is the only AAA light that the UltraFire 10440's will fit in, as they are so long) the UltraFire's only run about half (or less) as long as AW's 320 mAh 10440's. Not very impressive cells.

One question, if you charge the cells up to 4.20 Volts, what is the open circuit voltage after you let them sit for a few hours? If the voltage drops in that time to anything below 4.00 Volts, the cells are at EOL.

Dave

EDIT: Sorry hazna, I reread your post and see you do not have your meter yet. Please let us know what voltage you get after the cells rest a few hours after charging, when you receive your DMM.

 

[hazna]

So most people seem to believe it is an issue with the battery and not anything to do with the flashlight?

 

[VidPro]

So most people seem to believe it is an issue with the battery and not anything to do with the flashlight?

mabey you could also include the probability that running a 3.6v cell in a 1.5v flashlight that the light probably uses a Boost Curcuit, and goes more into a direct drive when the batt is fully charged.
so the drain on the cell at first is very high, the cell probably cant even keep up with the drain, therefore choking a bit anyways.

the 10440 is a Unprotected cell, and you put it into a Boost curcuit item, after a few runs of it, without noticing the critical low battery levels, you will destroy the battery, overheat the light, and have Loads of fun and bright output for a while. :thinking:

the cells themselves are not durable, they are doubly overrated, and have from 260-300ma , and in the light are probably being hard hit at first.
so at 4.2v-4.1V they are being drained quicker than normal, and at low voltages nothing Stops, because there is nothing TO stop it, so they Can be discharged to low, and ruined.

soo, you had your fun, now Pay for it lol, sorry just joking.
its not just the battery, its what your also asking it to do. take a few readings, and do a discharge reading on them, before you write them off. but you need to MANUALLY protect these cells.
The light itself should be able to handle it, so even though the voltage (charged) is proably to high, it probably is not an issue with such a lightweight battery item, so the light will be ok.

add to that the 10440s are all short lived in Age , so after a year or 2 they will be completly useless.
its a great battery and i am glad it exists, but there are many caveats to its lack of protection and small size , and those should be taken into concideration, even beyond it being a DX special

boost curcuit, boost voltage for battery voltages LOWER than the Led voltage, ex: battery actually outputting 4.0v in a boost drive (under load) will overdrive led
Boost curcuits are capable of battery depletion down to .7-.4v depending on the curcuit.
li-ion cell max discharge level 2.4v a few rounds at .9v even and its toast.

max charge for li-ion is about 1C when not pulsed, anything over and the cell becomes loose, and doesnt actually charge any faster, this internal "resistance" during too fast of charging, is probably not to good for it either.

when you get your meter thing in , you will find out everything you cant see now, and that will be a huge help.

 

[mudman cj]

My experience agrees with that of 45/70: if you want a 10440 that gives higher output for a longer time, then go with AW cells. They are still subject to the same issues that VidPro described, but they will definitely outperform Ultrafire cells. Not only do they have more capacity, but they hold their voltage under this type of load much longer, and therefore you can stay in high mode about twice as long.