Battery recommendation for an Eagletac M2XC4, and a few questions!

[mikekoz]

I currently have an Eagletac M2XC4 on its way, and an looking for a few 18650 cells for it. Right now, I have a bunch of these cells that I took from a few laptop battery packs. Most of them are Panasonic cells, and some are wrapped in a red covering, and I have no clue who makes them. I would first like some advice on which cells to use with my new light. I seee a lot of folks like the AW's, but I am looking for something with a bit more capacity than 2200 mAh. I would like at least 2400. I have seen Ultrafires rated at 3000 mah, but was told that figure was misleading. Any advice here?

Also, I have read about protected and unprotected cells. I would imagine these cells I have that were yanked from laptop battery packs are unprotected. I have not had any problems with them so far. I only use lights that take one of them, and from what I can gather, that is safer. The Eagletac uses two, but they are installed in a carrier side by side. I have had two unprotected cells go bad on me. They did not vent or anything, they just one day would no longer charge. These two cells I actually paid money for about a year ago. I think they were made by LG, so I will avoid that brand. I like the fact that these cells I have are made by Panasonic, which is a brand I have trusted for years. Are these cells dangerous in the way I am using them? I charge them in an Ultrafire charger in pairs, and I put the charger in a metal pan while they are charging. I normally do not use the lights they are in until the battery dies. After several uses of the light, I will take the cells out and top them off. Any advice here would be helpful.



Mike

 

[mikekoz]

 

[Bullzeyebill]

Mike, LG are very good cells, and I have owned several for years. they are, in fact my primarily used LiIon cells, that and two Pila 18650's. They are rated at least as good as Sanyo, Sony, Panasonic, and other top brands, maybe even better. Just need to pay a lot of attention to unprotected cells, and use a decent charger that will not top them off above 4.2 volts. Also, do not drain them too low, and if you do that accidentally make sure to charge them up right away. Do not leave them undercharged for any length of time. Important to have a DMM handy to measure their voltage. You do have a DMM, or voltage meter?

Bill

 

[mikekoz]

Mike, LG are very good cells, and I have owned several for years. they are, in fact my primarily used LiIon cells, that and two Pila 18650's. They are rated at least as good as Sanyo, Sony, Panasonic, and other top brands, maybe even better. Just need to pay a lot of attention to unprotected cells, and use a decent charger that will not top them off above 4.2 volts. Also, do not drain them too low, and if you do that accidentally make sure to charge them up right away. Do not leave them undercharged for any length of time. Important to have a DMM handy to measure their voltage. You do have a DMM, or voltage meter?

Bill

Yes I do. When I test these batteries, the voltage will at first read around 4.1 volts, then the tester will show a progressively lower voltage:thinking: They do this on two separate testers that I own. I have not used one in a while, as it has been this way for several months. The other one just "died"


Mike

 

[wapkil]

Also, I have read about protected and unprotected cells. I would imagine these cells I have that were yanked from laptop battery packs are unprotected. I have not had any problems with them so far. I only use lights that take one of them, and from what I can gather, that is safer. The Eagletac uses two, but they are installed in a carrier side by side.

Yes, the cells from laptop battery packs are unprotected.

In the M2XC4 they are placed side by side but I believe that they are connected in series so there is no difference in the electrical connections between the batteries in the M2XC4 and in other multi-cell lights.

It would be a good idea to check if the M2XC4 is prepared to take unprotected batteries. Some lights have a built-in protection logic that prevents batteries from overdischarging, some don't have it and rely on the protection circuit in the batteries (or the user).

If you are worried about the LiIon batteries safety, you may want to take a look at the supposedly safer chemistry versions (LiMN and LiFePO4).

EDIT: I just noticed that you wanted the batteries with at least 2400mAh so the safe chemistry ones, that are smaller than "regular" LiIons, may be not suitable for you. The safe chemistry batteries are also advertised as less likely to explode but most of them (if not all) currently don't have any protection circuit. They are also able to deliver much higher current than regular LiIons. If I understand correctly, it means that when they are shorted the current they will deliver is more likely to melt things or start fire.

 

[fareast]

I too have an M2XC4 on it's way :twothumbs. Can't wait.

So your looking for protected AW 18650's with protection but with at least 2400MaH? I ordered these:
http://www.cpfmarketplace.com/mp/showthread.php?t=197375
AW P18650 - 26 SPECIFICATIONS:

Constant Voltage : 3.7V
Capacity : 2600mAH ( rated at 0.2C discharge 4.2V - 2.8V @ 25℃ )
Operating Temp. : Charge 0 to 45℃ / Discharge -20 to 60 ℃
Max. Charge Rate : 2.6A ( ambient temp. 25 ℃ )
Max. Discharge Rate : 5.2A ( ambient temp. 25 ℃ )
Dimensions :18.52 X 68.16mm ( +/- 0.3mm )

I was just about to get a few more as spares myself.

 

[Bullzeyebill]

Yes I do. When I test these batteries, the voltage will at first read around 4.1 volts, then the tester will show a progressively lower voltage:thinking: They do this on two separate testers that I own. I have not used one in a while, as it has been this way for several months. The other one just "died"


Mike

Like I said earlier, my LG's are outstanding. Something is causing your problems with them, and maybe them being inactive for awhile and left charged above 3.80 volts or so is the the problem, not sure. Nobody posts about having problems with their LG's that I can recall. Does your charger charge cells above 4.1 volts? I think that LG cells, like most cells used in lap tops, need to be to charged to the fullest, 4.2 volts, or so. They were made to be hardy cells, and of course run in series/parallel with a quality protection circuit, but most computer batteries are abused over and over and still do pretty good over the long haul.

Bill