Features 1、Lithium battery charger for solar powered system. 2、Power supply voltage DC 4.4-6V, charging output voltage DC 4.2V. 3、Maximum charging current/output current is 1A, but you can change the current by changing the value of the R1 resistor. 4、Automatically adjust the charging current according to the output capacity of the input power supply. 5、Precharge adjustment for restoring deep discharge batteries and minimize heat dissipation at the initial charging stage. 6、Constant current/constant voltage operation with thermal regulation maximizes charging rate without overheating risk. 7、Automatic low power sleep mode when the input power voltage is removed. 8、C/10 charge termination. 9、Automatic recharge. 10、Battery overvoltage protection. Specification Item Type: Lithium Battery Solar Charge Module LED Indicator: ''CR'' LED is charge status indicator; ''OK'' LED is fully charged OR constant voltage mode Dimension: 18x10.16x2.7mm Options: with Pin, without Pin Weight: 0.9g(with Pin), 0.6g(without Pin) Instruction: The adaptive unit on the module can adjust charging current automatically based on the output capability of input power supply, so it is ideal for the solar-powered systems, or the applications that need to charge lithium-ion battery or lithium polymer battery with an input power supply whose output capability is limited. If your solar panel is 5V, then you can use it directly. Of course, the module can also be powered by a 5V DC power supply. Package List 1 x Solar Charge Module