Li-Ion safety circuit woes

[Kyosho]

I've got one of those portable DVD battery pack things. Basically the same one Ben used in his PS2p. All the cells seem fine and work fine. But the stupid safety board thing doesn't want to work most of the time. It'll work fine as long as you don't touch it, but if you so much as bump it, it throws its internal safety switch and kills the battery power. The only way to reset it is to plug it into its charger. I've checked to make sure all the components and wires have secure connections and cannot figure out what is wrong with it. It's driving me nuts.

I could probably buy a new safety circuit but honestly, I'm broke. That's not going to happen. From my understanding, the dangers with Li-Ion batteries lie mostly with over-charging them or draining them too far. If I'm very careful, do you think it'll be alright?

Here's what I'm thinking of doing: Rather than connect my portable to the power port on the safety circuit, I would connect it directly to the batteries, in parallel with the safety circuit. I realize this removes any function of "safety" that it provides while in use. However, doing it this way, the safety circuit would still be used when charging. That way, I won't risk overcharging the cells.

Would that be okay or would it still be too dangerous? I really don't want my portable to explode or catch fire or something, but I don't have any other batteries I can use.

 

[XCVG]

If you do it that way it will give you overcharge but no overdischarge or thermal protection. Meaning you could kill your batteries by draining them too much. You could also pull too much power at once from the batteries, but in a low-draw device like a portable it's not really a problem.

 

[Basement_Modder]

Your broke? Save up $10, and you can get one off batteryspace shipped.

 

[Kyosho]

There is no saving when there is no income. I'm currently unemployed.

XCVG, didn't think about the too-many-amps-at-once thing. Hmm. I think I'll be okay in that regard.

So, lets say that I did over-discharge the batteries, hypothetically speaking. Would it be bad to charge them, then? If I'm using the safety circuit to charge them?

 

[XCVG]

If you over-discharge your batteries you could swell them up. They would be dead. If you don't swell them up, you might have still killed them. If you've killed them they shouldn't explode but they won't charge and won't hold a charge.

 

[Kyosho]

Hmm. Alright, thanks. Definitely something to keep in mind.