I read reviews, reviews, settled on a Samsung power bank. Heavy, you immediately feel that there is something inside. For some reason, it doesn’t charge more than 5 volts with the cable included, but it can charge like that. With the Aukey PSU, it charges only from 5V, with Xiaomi 9V, but this phone does not take more than 9V. Any voltage is set manually by the USB tester. Fully discharged, charged only 4.8A, see screenshot, FIRST FNB48 tester.