6PCS 18650 Battery Charger Protection Module Dual USB 5V 1A 2.1A Power Bank PCB Module Board with BMS Protection for Phone DIY Mobile Power Bank Board

Specifications: Micro USB input: 5V 1A USB Output: 5V 2.1A / 5V 1A(Dual USB interface) Charging display: intelligent digital display Batteries Type: liquid lithium-ion batteries (18650) Attention: 1. The B+ and B- connected to the boosted battery must not be reversed. 2. Long press the switch, the manboard will turn on the USB output,long press it again to turn off the USB output; Press the switch twice to turn on the lamp, and press twice again to turn off the lamp 3. When use the board at first time, please connect 5V power adapter to the micro USB port to activate the board. 4. It support multi battery in parallel connection. How to choose the right battery: The battery should be flat 186 50 battery, 65mm long, pointed battery can not be used. If you use old batteries, different capacities, different brands are not available, disassemble the battery to ensure that each voltage is at least 3.5V or more, if the voltage is too low, then you can put it into the battery. (Note: You can also use lithium battery, mobile phone tablet battery) How to distinguish between battery +-pole and power box +-pole: In general, the 186 50 battery has a negative electrode in the plane, and a positive hole in the hole. Must not be installed anti-battery, anti-burn once installed, and then loading pairs is useless. Why is there no power output after the battery is installed: After installing the battery, you must plug in the 5V charger to activate it. Why can't continue charging when charging capacity is 99%? You just assembled the battery, why the display percentage is not accurate, the battery power is only 50%, but it shows 80% after assembly?--Whether you are using a new battery or an old one all need to be discharged before use(charge your mobile phone), then turn it off charge it once gain. If it stil