Fun little gadget - limited practical values
This item ([[ASIN:B003EW82ZG T-5000 Hybrid Solar Battery Charger AA NiMH USB Power]]) looks like a versatile product. It is very compact (same size as a deck of playing cards), and offers multiple functions. You can:<br /><br />1. Use it as a solar-powered charger: to recharge two internal AA NiMH cells under direct sunlight<br />2. Use it as an USB-powered charger: to recharge internal AA cells from an USB port<br />3. Use is as an USB power source: to recharge cell phone or other gadgets from internal AA cells<br /><br />Upon closer examinations, however, each function turns out to be poorly implemented:<br /><br />1. The solar panel is quite small (4x7cm). Even under direct sunlight at noon time, with the panel perpendicular to the sun beam, the maximum charging current is just 100mA. In real life it will take about 3 sunny days to fully recharge a pair of 2100mAh cells. The case is not weather-resistant, so it should not be left in the open. But when I placed it under the windshield of my car, the charging current dropped by 50% because the glass is UV-filtered.<br /><br />2. When powered from an USB port, the two internal AA cells are continuously being charged at about 125mA. The problem is there is no 'charging done' signal. The little green LED simply remains on forever, even when there are no batteries inserted. You have to unplug the USB cable after about 20 hours, to prevent over-charging of internal batteries.<br /><br />3. When used as a USB power source, the 5V output it generates is limited to 300mA max., which is lower than the 500mA from a normal USB port. I have used it successfully to recharge my [[ASIN:B0024FAC16 Philips GoGear Aria MP3 Player]] and my Motorola W755 cell phone. However, if you want to use it to recharge a higher-power device (such as any smart phone or internet tablet), 300mA is just not sufficient.<br /><br />In summary, the T-5000 Solar charger is still a reasonable value if you can use it as a cell-phone charger. But it is not practical as a solar charger during hiking trips, because the case is not weather-resistant. For smaller size and less weight, you could bring an extra set of [[ASIN:B00003IEME Lithium AA Battery]].<br /><br />By the way, if you need a solar charger and battery pack that can provide at least 1000mA output current, consider the [[ASIN:B005ZSSBYY Opteka BP-SC4000]] instead.
Rating: 3 stars