Unihertz 8849 Tank Pad Review

Battery Tests

Unihertz 8849 Tank Pad boasts a 21200 mAh battery pack with 66W fast charging support and a respective charger included in the box. All battery tests we run on the devices we review are developed by us and performed with the screen of the device being calibrated to 200 cd/m². Battery-saving features (if any) are disabled. The battery of our review unit was charged in full for 1 hour and 46 minutes with the provided USB cable and charger. The charging process develops steadily from the start until the battery regains 96% of its charge when it slows down a bit. The stable process results in a stable battery temperature that fluctuates from 28°C to 32°C during charging. During our intensive browsing test with the display's refresh rate set at 60 Hz, the battery of our review unit lasted for 24 hours and 25 minutes. The discharging process is steady with a minor drop at the very beginning. The battery temperature starts at 25°C, reaches 28°C in 1 hour, and hits 29°C after the 15th hour, remaining at this level until the end. With the display's refresh rate set at 90 Hz, the battery of our review unit lasted for 23 hours and 9 minutes. The discharging process is identical to that observed from the 60Hz browsing test. The battery temperature starts at 24°C, reaches 29°C in 1 hour and 45 minutes, and remains at this level until the end. When the refresh rate is increased to 120 Hz, the result from the browsing tests drops a bit to 21 hours and 2 minutes. The discharging process draws an identical graph and the battery temperature shows a similar behavior. It starts at 24°C, hits 29°C in 1 hour and 25 minutes, and maintains this level until the end. The video test for battery life uses a 1080p video at 30 fps with a ~20Mbps rate. Our review unit's score is 23 hours and 30 minutes. The discharging process follows the same pattern observed during the browsing tests. The battery temperature starts at 27°C, reaches 28°C in 15 minutes, and maintains it for 15 hours and 30 minutes. After that, the temperature goes up a notch to 29°C and remains at this level until the end. The 4K video battery life test uses a 2160p video at 30 fps with a ~55 Mbps rate. In this test, the Tank Pad battery lasted for 22 hours and 33 minutes. The discharging process graph is identical to the one from the previous tests. The battery temperature starts at 31°C, drops to 28°C in 1 hour and 30 minutes, and maintains this level for 15 hours. After that, it reaches 29°C and remains at this level until the end. For the 3D Graphics/Gaming test, Real Racing 3 is used. The result from this 60Hz gaming test is 19 hours and 47 minutes. The discharging process follows the same pattern observed during the previous tests. The battery temperature starts at 25°C, reaches 29°C in 1 hour and 20 minutes, and remains at this level until almost the very end, when it goes up to 30.5°C. After the display's refresh rate is set to 120Hz, the result from the gaming test is 16 hours and 50 minutes. The discharging process follows the same pattern observed during the other tests. The battery temperature starts at 26°C, reaches 30°C in 1 hour and 30 minutes, and remains at this level almost until the end - 50 minutes before the end, it increases to 31°C.

Battery Settings

The Battery menu is quite simple. It gives the usual battery status information, usage data by app and service, a battery percentage toggle, and a battery saver with the option to set a schedule and turn off the saver automatically when the battery is charged at 90% or above.