Amazfit has launched its $649.99 T-Rex Dual Solar, a rugged smartwatch with a 1.32-inch AMOLED screen and solar panels on both sides. It is rated for 25 days of typical use, but early tests suggest sunlight may add only modest battery life.
Amazfit says three hours of daily exposure to 50,000 lux can extend battery life to 34 days using the front panel or 51 days using the rear panel. Its 180-day figure requires Outdoor Extreme Mode and the same daily exposure through the rear panel; the mode reduces power demands and is intended for extended outdoor trips.
One hands-on test found that three hours of direct sunlight on the rear panel added about 2% to battery capacity. Another tester found that a full day outdoors could largely offset normal battery drain, but did not produce a dramatic increase in charge. Solar is therefore a supplement to charging, not a replacement.
