Today we are looking at Mi power bank, a budget power bank that is really getting everyone hyped up, but can cheap be cheerful? Let’s find out. On the website is promoting itself to have also those fancy features common among other branded power banks, what is unique is the nine layer circuit protection built by Texas Instruments so expect the controller to be absolute best but you might be disappointed.
Its weighs 156 grams, 9.9mm thick making it one of the lightest and slimmest power bank in the market. The anodized aluminium finish gives it the premium look and toughness to withstand any abuse but it prone to scratches over time AKA cosmetic wear and tear. Just one USB port and a 4 step power level indicator.
Now to the performance bit. The basic specification detail shows the rated cell capacity is 5Ah at 3.7v or 18.5Wh, the minimum capacity guaranteed is 4.88Ah or 18.05Wh at 3.7V and the minimum output guarantee is 3300mAh at 5V. The rated input is 5V at 2 amp which we gotten 1.88amp that is the best we gotten from different setup and device. The rated output for the one port is 2.1 amps which we gotten 2amps max. So is close to what is advertise, nice.
So here is the diagram to show the total output and input in mAh.
The total input: Total received is 4728 mAh at 5V or 23.64Wh converting to 3.7 equiv is 6389mAh
Total total output: Total charge is 3207 mAh at 5V or 16.04Wh converting to 3.7 equiv is 4335mAh
So the total out almost match the minimum guarantee total out of 3300mAh which we gotten 3207mAh which is close. Based on total output against total input the actual conversion charge received is 67.83%. Under 75% which I set as minimum standard (check out the youtube video for the graph comparison against different power bank), not sure how they calculate the 90% rate but I hope they reply my email.
I would recommend getting a slim power bank as it can fit well in bags without taking much space which I also like putting it my pants to travel around with it as I may not carry a bag all the time. It does perform as advertised for the input and output amps and the minimum capacity it can hold up but the Texas Instrument controller is a mere marketing tool and the conversion is under 70%, yes its cheap but cheap controller is not good, I’m hoping the make the next version to be better.