Used the PB0059E Imported main chip, high integration, synchronous boost&switching, High efficiency.
1. 2.1A synchronous boost conversion, 2.1A synchronous switch charging
2. Boost efficiency up to 96% MAX
3. Charging efficiency up to 94% MAX
(it is chip theory efficiency, not equal to the final efficiency, but better than the normal charger module)
4. Constant voltage - constant current standard discharge curve
5. Turbulent-constant current-constant voltage standard charging curve
6. Adaptive charging current adjustment, matching various current adapters ◆ Charging voltage accuracy: 0.5%
7. Support 4.2/4.3/4.35V battery charing
8. The charging has OVP protection, the charging is turned off when it is over 6V, and the instantaneous withstand voltage is 10V.
9. Support battery capacity display
10. Press the button to power on, press and hold for 3 seconds to shut down, standby power consumption is less than 20uA
11. Load insertion automatically starts boosting, load removal automatically sleeps;
12. Power MOS built-in, single inductor for charging/discharging
13. Multiple protection: Output over-current, over-voltage, short-circuit protection; input over-voltage, over-charge, over-discharge, over-current discharge protection; typical application of over-temperature protection
14. Support charging and discharging at the same time
With over discharging（about 3.2V） / over charging(about 4.2V)/ over current protection,
suitable for lithium li-ion 18650 battery DIY
Power bank, phone charger.
Notes: the battery polarity should connect correctly, or will burn the board.
Positive feedback.
or Negative 
feedback, so that we can satisfactorily address your concerns.
