This module is use a USB 5V mini to charge a Lithium ion battery. With LED indication. This module use IC TP4056 (Datasheet). If you want to change the charging current, you can change the resistor as in the table

The Module also has battery overcharging and over discharging function. It will cut the circuit if the battery are overdischarged to 2.5V and over 3A discharge current. This will protect the battery from dying