Greetings:
I charged an AW RCR123 on a UF WF-139 charger using a spacer, and monitoring the cell voltage while connected to the charger with a multimeter.
When the green light came on, the cell voltage was 4.67V . Immediately upon removing the cell from the charger, the cell voltage was 4.16V .
The open circuit voltage from the charger is 4.96V .
I suspect what is actually happening is that the cell's protection circuit is opening the circuit to the charger before the charger senses that the cell is fully charged. This might be due to the tolerances on the protection circuit being a bit low. I don't observe this behavior with AW 18650 cells (which I can't recall what voltage they terminate at).
However, if this idea were true, then I might expect to measure the open circuit voltage of the charger across the cell. OTOH, the protection circuit might be drawing some current from the charger, slightly reducing the voltage, but not letting the cell receive the current.
I don't believe the cell is getting overcharged because the voltage is actually modest at 4.16V when I take it out. If it was over a safe voltage when taken out then I would be greatly concerned.
Has this been observed by anyone else? Ideas?
I charged an AW RCR123 on a UF WF-139 charger using a spacer, and monitoring the cell voltage while connected to the charger with a multimeter.
When the green light came on, the cell voltage was 4.67V . Immediately upon removing the cell from the charger, the cell voltage was 4.16V .
The open circuit voltage from the charger is 4.96V .
I suspect what is actually happening is that the cell's protection circuit is opening the circuit to the charger before the charger senses that the cell is fully charged. This might be due to the tolerances on the protection circuit being a bit low. I don't observe this behavior with AW 18650 cells (which I can't recall what voltage they terminate at).
However, if this idea were true, then I might expect to measure the open circuit voltage of the charger across the cell. OTOH, the protection circuit might be drawing some current from the charger, slightly reducing the voltage, but not letting the cell receive the current.
I don't believe the cell is getting overcharged because the voltage is actually modest at 4.16V when I take it out. If it was over a safe voltage when taken out then I would be greatly concerned.
Has this been observed by anyone else? Ideas?
