A more technical capacity measurement of the Flare powerbank from Cherry Mobile using a 1 Amp load and a watt meter.
I dismantle the power bank and desolder the battery pack from the control circuitry. We typically expect losses of around 10% where the board is boosting the batteries 3.7V up to 5V for USB output.
Directly from the batteries, we measured a total output of 26.16Wh compared to the earlier result of 23.27 Wh when drawing power through the USB port. That’s an 12% improvement which is pretty much exactly what we expected.
Even under these best case tests, without any losses from the PCB, this only results in a rating of around 7,000 mAh instead of the advertised 10,000 mAh.