ZUK, Lenovo-backed startup introduced ZUK Z1 smartphone in China back in August. We already brought you the review of the smartphone, here we have its battery test results. The ZUK Z1 packs a 4100mAh built-in battery and has fast charging capabilities. It has a 5.5-inch 1080p display and is powered by a 2.5GHz quad-core Snapdragon 801 SoC. Check out the battery life test charts below.