Input port with micro USB female, can directly use mobile charger for input to the lithium battery, and still retain the input voltage wiring solder joints, can be very convenient.

Connect the battery to B + B -, insert mobile phone charger to the USB Female then red light is charging and green is full of charged.

This tiny module is perfect for charging single cell 3.7V 1 Ah or higher LiPo cells such as the 18650s that do not have their own protection circuit.
Based around the TP4056 charger IC and DW01 Deep Drain Battery Protection IC this module offers a 1A charge current.
The module cuts off the charging current when finished.

Furthermore when the battery voltage drops below 2.4V the protection IC will switch the load off to protect the cell from running at too low of a voltage – and also protects against over-voltage and reverse polarity connection (it will usually destroy itself instead of the battery) however please check you have it connected