Today I was checking the voltage between charging terminals going to the battery of emergency lantern using a multimeter.
The multimeter showed a DC voltage of 9V and an AC voltage of 4V.
Could this AC voltage have damaged by old battery?
The DC voltage while being measured was not constant and the decimal part was changing in a cyclic pattern.
I only saw 3 diodes on the board. Is this a half-wave rectifier and is the multimeter mistakingly showing the ripple of half-wave as an AC voltage.
Please see the image of the circuit.