Test/review of Xtar PB2 Charger & power bank

[ActiveAl]

@HKJ

Efficiency will be best with highest input voltage and fairly low current drain (How low depends on the consumption of the circuit itself), I would not expect much if any difference between one and two cells. The problem measuring efficiency is that I need to measure the battery current, this requires I put something between the battery and the boost converter in the box. I have only made one sensor for this, if I wanted to do it for two batteries I would need two sensors and four voltmeters on the battery side (Or open the box and mount a resistor between batteries and boost converter).

HKJ, thank you for the quick reply - and your good, hard work. Could you make a qualitative assessment of the PB2 power bank USB out efficiency in comparison to others that you have tested? Would you say it Is above average, for example? What do you think of the manufacturer's claim of up to 92% efficiency? Thanks.