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I bought this light from banggood, partly because it looked like it had a decent solar panel and partly because it wasn't getting good reviews.
It's definitely not designed for maintenance.
Provisional tests show that on a bright but cloudy winter day the panel output was about 70mA. I'm going to have to do side by side comparisons with other solar modules. It is indicative of what I'd get here on a typical December day with good panel placement. At the moment it doesn't bode well for all-night illumination. It's probably going to spend a lot of time at a very low battery voltage in the winter here. Probably much better in sunnier parts of the world though.
I still have to finish testing the lithium cell which turns out to be Lithium Iron Phosphate (LiFePO4) (The charging stopped at 3.65V) with an early indication of about 3000mAh, but further full cycle tests are in progress. This has probably been chosen for its stability and high charge/discharge cycle capability. That also explains the need for a boost regulator circuit to allow a stable 3V supply to be obtained for the sense circuitry. It also blows my current test figures out the water. A retest shows:-
Full charge (3.6V) high output 1100mA (3W at an LED voltage of 2.9V)
Full charge (3.6V) low output 140mA (0.4W at an LED voltage of 2.65V)
Low charge (2.8V) high output 269mA
Low charge (2.8V) low output 40mA
The power resistors run at a very acceptable 40C above ambient when the high setting is triggered continuously.
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