I now use these very cheap chargers for my 18650’s … I have four of them and have fitted a heat-sink to the back of the boards … The heat-sink isn’t essential , but it reduces the chip temperature by 15C and they were easy to attatch with special double-sided tape.
Suits me fine as they come ready to charge at one amp , so no need to change the value of a resistor to reduce the charge current … My Panasonic 3100mAh protected cells are charged to perfection using these … Certainly at least as good as the majority of other ready-made Li-Ion chargers … There is also the option to parallel two of these boards to increase the charge current if needed.
Highly recommended.
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