I got a mi 2i 10000mah power bank and using since past 2 months. It gave a good power backup than the past others Power Banks I used, I have Lenovo k4 note which comes with 3300mah li-poly battery, it charges my phone 2.5 times and the most important(It charges my phone faster than compared to my phone’s original charger).
Really impressed with the product I got it looks premium with a metal casing outside.
SPECS; it has li-poly battery inside with a smart chipset which gives your power bank Over Charge protection.
OUTPUT= 2 2.4A 5V / 12V 15W max.
INPUT =5.0V 2.0A / 9V 2.0A.
CELL CAPACITY= 10000mah 3.7V.