Inside a rechargeable desktop lamp

I bought this lamp a while back on amazon

It is really handy, cheap, no cable attached, and  usb rechargeable.
Lately i noticed it was discharging REALLY fast, with very little use

Time to open it up :

1: SMD - 312F- Battery protection circuit
2: SMD - 8205- Mosfet
3: SMD - 57ba - Battery charge circuit
4 HC8T046 - small MCU

So there is a protection circuit on the main board, and none on the battery itself.

Let's look at the battery :


1200 mA/h on the package, that's not much to start with.
Let's check how much there is actually : ..... 600 mA ! It decayed really fast already.

Let's put a spare battery from an old laptop  instead, measured at 1300 mA and back in business



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