Why do protection circuits fail so easily?

[exodus454]

4/5 of the 14650's I've had for my epower, the protection circuits bit the dust.

Two of them I dropped and the batteries stopped working - remove the protection circuit and they work good as new again. When I took them apart they had separated from the little terminals that run to the positive end of the battery. I tried to fix the connections but nothing got them working again. I'm not comfortable soldering to a battery myself.

Two of the others just stopped working period. Would still charge and hold a charge, but when I put them in the epower the light would just blink whenever you hit it like the battery was dead. Remove protection circuits and good as new again.

Now, it scares me quite a lot knowing I'm currently using unprotected batteries, therefore I'm being obnoxiously careful with them. I don't have any other batteries to fall back on though at the moment. But on the other hand, this is RIDICULOUS to have to buy so many batteries and they fail because of the $.10 circuit onboard.

So how dangerous is it really to use them? The protection circuit only protects against high-drain (short or overload) situations damaging the cell, right? Do they limit the discharge also so you can't run the cell flat?

 

[cozzicon]

4/5 of the 14650's I've had for my epower, the protection circuits bit the dust.

Two of them I dropped and the batteries stopped working - remove the protection circuit and they work good as new again. When I took them apart they had separated from the little terminals that run to the positive end of the battery. I tried to fix the connections but nothing got them working again. I'm not comfortable soldering to a battery myself.

Two of the others just stopped working period. Would still charge and hold a charge, but when I put them in the epower the light would just blink whenever you hit it like the battery was dead. Remove protection circuits and good as new again.

Now, it scares me quite a lot knowing I'm currently using unprotected batteries, therefore I'm being obnoxiously careful with them. I don't have any other batteries to fall back on though at the moment. But on the other hand, this is RIDICULOUS to have to buy so many batteries and they fail because of the $.10 circuit onboard.

So how dangerous is it really to use them? The protection circuit only protects against high-drain (short or overload) situations damaging the cell, right? Do they limit the discharge also so you can't run the cell flat?

What brand are the batteries?

 

[thepassionofchad]

My girlfriend dropped her battery and it went kaput. Removing a protection circuit just sounds.... dangerous.

 

[donnah]

It may not be your batteries. On my vv box mod sometimes that atty I am using gets some crud in it just the right way and it registers too low of a resistance and trips the protection circuit. I can tell this because I can take the batt out, and put it right back in to reset it and I can take a draw and then it cuts off again. I bought some AW IMR's and this solved it. It drove me crazy trying to figure it out till someone told me what was happening.. haven't had any problems since.

 

[exodus454]

What brand are the batteries?

ultrafires and whatever the brand is that came with the epower

It may not be your batteries. On my vv box mod sometimes that atty I am using gets some crud in it just the right way and it registers too low of a resistance and trips the protection circuit. I can tell this because I can take the batt out, and put it right back in to reset it and I can take a draw and then it cuts off again. I bought some AW IMR's and this solved it. It drove me crazy trying to figure it out till someone told me what was happening.. haven't had any problems since.

I've pretty much ruled this out already.. even across different cartos with the same device, different batteries behave differently. And even so, the protection circuit should theoretically reset itself when it trips - every battery I've had giving me issues will just stop working.