LiPo battery question

[hiyall]

i have a small 500mAh battery. it only has 2 wires and possibly a protective circuit. would i be able to remove the protective circuit and solder a new one on that is not the same as the old? considering that the voltage is 3.7v. this new circuit protector will then have 4 wires coming from it opposed to the old one that had only 2.

would this be safe?

what im doing is replacing a battery for a device that had a bad battery and i remove the old circuit protector from the dead battery and put it on a different one

 

[mrmez]

I wouldn't. Especially since you can probably buy a decent replacement for $10.
Lithium based batteries are delicate, and dangerous. Just google something like exploding battery for potential dangers.
Imagine charging that battery for the 1st or 100th time and it bursting into flames when you're not there. Best case you get some damage to your stuff. Worst case your house burns down when you're sleeping.
Worth saving $10?

 

[mrmez]

https://www.anker.com/products/variant/PowerCore-5000/A1109011

There's 10x the capacity (5,000mah) in one of the best brands for $15.99

 

[hiyall]

I wouldn't. Especially since you can probably buy a decent replacement for $10.
Lithium based batteries are delicate, and dangerous. Just google something like exploding battery for potential dangers.
Imagine charging that battery for the 1st or 100th time and it bursting into flames when you're not there. Best case you get some damage to your stuff. Worst case your house burns down when you're sleeping.
Worth saving $10?

i understand but if all cells add up to 3.7 volts for both batteries, why would there be harm for installing a new protective circuit onto the 2 tabs that protrude into the cells to make a connection. that battery is too big. i would assume inside is a 18650 battery. i just need a small 500mAh LiPo battery for a music device that needs a new battery

 

[InvalidError]

Unless you know for certain that the reused battery protection board has the correct voltage and current limits for the new cell (which I doubt you do), then I wouldn't recommend messing around with protection circuits. LiPo batteries have a handful of chemistry variants with slightly different end-of-charge voltages and different tolerance to over-charging.

Putting a protection circuit which has higher limits than what the new cell is comfortable with can lead to disaster as others have already pointed out.