These are made in China, and are made as cheep as possible, they have a AAA rechargeable Cell inside that is over worked and the one I have failed after 5 weeks. The charger states Voltage output 2.4v but is actually 5.07v output. There is NO full charge indicator (The LED dose not change colour even after 24Hrs). I replace the AAA Cell with a AA rechargeable Cell after making some extra space in side by removing some plastic and it works as new. The saying goes "you get what you pay for" In this case You DON'T.
Any updates on this? I have the same AAA 1.2v battery, I happen to have a 3.7v lithium ion battery, I'm thinking about replacing it, but will this burn the motor of the trimmer? If someone can help me here, would be awesome