M2CX4 suck battery power fast?

[picard]

holly s***. My M2XC4 sucks battery power like crazy. I used it on high intermittently for 20min and it shuts off. I have Ternergy 18650 3.7V 2600 maH.

Does anyone notice the M2 use up battery power that fast?

 

[richardcpf]

Thats weird.. mine did almost 1 hour with intermitent use, but the first time I left it alone for 20 minutes it got so hot I couldn't even hold it. The light shut off by itself and I was able to turn it on again when it cooled down.

 

[strinq]

Hi bro, it could be the batteries.
Cuz the few reviews and tests here shows that it should last about 1 hour with fully charged batteries.
I have one too but i haven't tested a continuous run but i'm pretty sure i've used it for more than 20 minutes on max already.

 

[picard]

Thats weird.. mine did almost 1 hour with intermitent use, but the first time I left it alone for 20 minutes it got so hot I couldn't even hold it. The light shut off by itself and I was able to turn it on again when it cooled down.

mine M2 doesn't get that hot. I have to recharge it and test again tomorrow night.

 

[tebore]

Sounds like the protection circuit of the battery is kicking in early.

 

[picard]

Sounds like the protection circuit of the battery is kicking in early.

why does protection circuit kick in early?

Can I use unprotect cells on the M2 so the light would last longer?

 

[FlashlightsNgear.com]

I just ran mine on high for 30 min straight, it got warm but no were near hot. My EZAA gets HOT! But not the Eagletac. I get atleast a hour (on high) out of 2 Protected Trustfire 2500maH 18650's. The Tenergy batteries could be the culprit in your case of short runtimes and the light getting hot.

 

[picard]

I just ran mine on high for 30 min straight, it got warm but no were near hot. My EZAA gets HOT! But not the Eagletac. I get atleast a hour (on high) out of 2 Protected Trustfire 2500maH 18650's. The Tenergy batteries could be the culprit in your case of short runtimes and the light getting hot.

Does Ternergy battery protection circuit tend to kick in early?

 

[Robert_M]

I haven't used my M2CX4 (cool tint) on rechargeable batteries yet ... but on primaries I would guess I've used it intermittently for about 45 minutes on turbo so far over the past month and according to my light meter & light box, the output has not dropped yet. You may want to consider doing a run time test using a cooling fan like Selfbuilt does (light meter + light box). Or just run it under a cooling fan until the battery protection circuits kick in or the light output is low. Then repeat for a different brand of rechargeable batteries and/or primaries. Then you'll know if your particular flashlight has a problem. Hopefully, its just your batteries.

 

[picard]

I test the same Ternergy battery on the DBS V2 and the light works fine. I think the M2 heat up quickly thus battery shut down.

 

[FlashCrazy]

I test the same Ternergy battery on the DBS V2 and the light works fine. I think the M2 heat up quickly thus battery shut down.

I'd suspect your batteries aren't holding voltage under load as well as they should. Fully charged, the batteries should read 4.1-4.2 volts each. When the flashlight is turned on, the batteries immediately sag to a voltage of about 3.7 volts each, assuming they're in good condition. When the batteries are worn, they may drop to 3.4 volts are less when the light is turned on. In this case, they'll reach the low-voltage protection threshold of ~2.8V per cell very quickly. I've seen worn batteries that instantly sag to the shutoff voltage in a matter of a couple of minutes. This can happen even though the batteries read normal voltage off the charger. The only true way to determine a batteries state of health is to do a measured discharge.

Ok, with all of the above taken into account, the M2 places a higher load on the batteries than the DBS does. This will cause worn batteries to sag in voltage much more quickly... that's why the batteries appear normal in the DBS... it's just not asking as much from them. Don't misread this as a negative against the M2, it's just due to the fact that the M2 is pushing a lot of current to it's quad-die LED... there's essentially four dies to feed, afterall. (or three regular LED's in the case of the M2X).

And as far as getting unprotected cells instead, I wouldn't recommend it. Protected cells protect not only against under-voltage, they also protect against over-charge (over-voltage) during recharging, over-current, and short-circuiting (which is also over-current). These are valuable safety features that may well save your house from fire, and save you from injury. Not bad insurance for giving up a couple of bucks and a few minutes of runtime.

 

[richardcpf]

Can I use unprotect cells on the M2 so the light would last longer?

Yeah you actually get better result using unprotected cells when the setup is in series.

Because no battery is same from any other, one will always drain faster than the other one, and the protection circuit will kick in first. Leaving an open circuit, so even that the other battery holds a reasonable amount of charge, the flashlight won't turn on.

Tried my new fire wrapping ultrafire 2400ma batteries and the runtime in high (not turbo) runtime was a little bit less than 3 hours. One battery went into ptotection mode, but the other one still provided about 30 minutes of light with my fenix tk11 in turbo.

 

[Yucca Patrol]

I use the same Tenergy 2600 batteries and mine has run over an hour on a dog walk on the brightest settings.

 

[jirik_cz]

M2XC4 lasts 90-105 minutes with good quality batteries (AW 2600, EagleTac 2400...). You should try them.

 

[strinq]

Just tested my unit and it was about an hour or plus a little more with my batts.
Did get pretty hot but it was a hot night with no wind but it was still well within the range of being holdable.

 

[strinq]

M2XC4 lasts 90-105 minutes with good quality batteries (AW 2600, EagleTac 2400...). You should try them.

Do they last so long?
Mev states 53 minutes for the AW and selfbuilt at 80 minutes.
Mine was like 60-70 minutes on 2 x Trustfires before the proctection circuit kicked in.

 

[richardcpf]

Do they last so long?
Mev states 53 minutes for the AW and selfbuilt at 80 minutes.
Mine was like 60-70 minutes on 2 x Trustfires before the proctection circuit kicked in.

Maybe it depends on the heatsinking... If the flashlight runs cool it will work more efficiently, I guess.

 

[strinq]

hmmm true that.
Mine was definately running a little hot.

 

[jirik_cz]

Do they last so long?
Mev states 53 minutes for the AW and selfbuilt at 80 minutes.
Mine was like 60-70 minutes on 2 x Trustfires before the proctection circuit kicked in.

Yes. These tests were done with a mild airflow to simulate a walk. But it shouldn't affect the runtime in a significant way.