Wrong behavior li-ion battery charger
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A word of advice: scrap it ASAP. This thing can be dangerous.

For debugging:


measure voltage across R2
measure voltage across R3
measure voltage across R4


From the circuit LED2 is supposed to be flashing during charging.

EDIT: forget the comment system, this is far better.


the transistor used is not strong enough
please keep in mind that the RED LED forward voltage can vary by as much as 15% from LED to LED at room temperature
please note also the temperature coeficient of the forward voltage: 2.1mV / C
TL431 would work, why the TLV then?