18650 dangers?

[things]

Hi, i've just received my flashlight from dealextreme, and I also forgot to order some 18650's with it. Now, I've recently pulled apart a laptop battery that has lost it's capacity, and it turns out it has like 12 18650's in it

So i've extracted 2 of them, and they work in the light fine, and I also bought a ultrafire charger to charge em with. Would these batteries be fine in the flashlight, even though they are pretty dead? well, they may not even be dead, but I have had them on charge for about 2 hours now and they are barely even warm, which is good to know (Though I do check them every so often)

Should I be worried about fires/explosions more with these batteries, then, if I bought some new ones?

The flashlight is extremely bright (rated 900 lumens), which indicates the batteries are working fine (Although havent done any longetivity tests yet)

Is there any more dangers to using used batteries than new ones?

Cheers,
Dan

 

[Glock27]

I wouldn't use unprotected cells in a multi-cell light.
I use harvested laptop cells in single cell lights. My single cell lights shut off before over discharging the cells. I also use a Pila charger which charges cells correctly.
G27

 

[things]

I wouldn't use unprotected cells in a multi-cell light.
I use harvested laptop cells in single cell lights. My single cell lights shut off before over discharging the cells. I also use a Pila charger which charges cells correctly.
G27

Hi, this is just a single cell light

The batteries also have a small ring around the + terminal, I have thought that that would be protection?

Cheers,
Dan

 

[Black Rose]

Batteries from laptop packs are unprotected...the circuitry within the laptop handles the protection aspects.

 

[Glock27]

Protected cells have a small circuit board at the base or Negative end. Laptop cells will be unprotected.
I think the greatest Li-Ion danger is charging. Protected cells give a greater degree of safety as they "should" open the circuit if overcharged or overdischarged.
G27

 

[things]

So is it safe for me to use them with this flashlight? I guess it just means I have to be extra careful when I am charging them, and turn it off if the light starts to get noticeably dim?

Cheers,
Dan

 

[Bullzeyebill]

I would invest in new 18650's for your single cell light. Either protected or unprotected. You are just pulling too much from those old cells with that high drain light of yours. I use LG unprotected for single cell applications with fairly high drain and like the previous poster said, the light dims before there is an over discharge.

Bill

 

[putbinoot]

what a place, still waiting on my batteries to arrive i stumble upon this thread and so go down and get my dell laptop pack that i replaced with a bigger pack and open it up there staring me in the face was 6 lovely looking 18650 cells. Flashlight now on and bright.

cheers guys.

 

[ANDREAS FERRARI]

Protected cells have a small circuit board at the base or Negative end
G27

The protection circuit is at the base of the battery-no laptop I know of has this-absolutely no reason to! I know it's tempting to harvest batteries from expired laptops,but it's not worth the risk if you don't know what your doing!

 

[325addict]

I also use LG 18650s from old SWIT battery packs. They even work fine with my Wolf-Eyes MC-E light that draws two amps(!) from the battery....

This driver however, sucks them fairly empty. When you have barely over 3 Volts resting voltage after a 10 minutes rest, it has been over-discharged. No doubt about it!

From a certain moment, a fairly sharp decrease in brightness can be seen. After that, I ran it fro several minutes.... THAT was wrong!! Now I know, that as soon as the brightness drops, I'll have to turn off the light immediately.
With the 2A draw, it has a runtime of exactly 60 minutes, so it should be 2Ah in capacity. And this is what I measured: 1977mAh.



Timmo.