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Lithium battery built in protection circuit

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LittleRain:
I got some batteries that I am using for a project, they have a small board on them, but I cant tell if they have any protection IC's on them due to it being folded over.
All I can see is its wires, but I'm pretty sure it does.

Even if it does have protection IC's, do I still need to add a charging circuit to my board?
The battery is just a standard 600mAh lipo, theone in this picture.

I was going to use this IC to handle its charging, but I'm not sure if I need it.
I have no idea what the protection IC's on lipos are, I'm guessing short circuit and over current, but does it handle charging as well?
The IC I plan to use is the LTC4054, here is link to datasheet.

So I guess what I need to know is, do I need to add that charging IC?

Siwastaja:
Yes, even if it has a protection circuit, you'll need a charger circuit, which actively controls charging current and voltage, and hopefully monitors temperature to prevent low-temperature charging.

The usual protection circuits just cut off completely with severe overcurrents, and with slight overvoltages, and have no means to actually limit current to safe values, just act like a resetable fuse in case they are greatly exceeded. Also, the protection voltages tend to be a bit over the normal operating values (like 4.25V or 4.30V instead of 4.20V) so that they won't trig at normal, intended operation.

MarkF:
It may be cheaper to just buy a charger...
For example:

  Mini-USB jack:  https://www.adafruit.com/product/1905
  Micro-USB jack:  https://www.adafruit.com/product/1904

LittleRain:
Ok thanks Siwastaja, very helpful.

MarkF, I'm not building a charger... I'm building a HID USB/Bluetooth device that charges via USB.

LittleRain:
Do I also need to provide under voltage protection?

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