After connecting the supply connect the 3.7V lithium ion cell you want to charge with the battery connections points shown in the image above. The li ion cell should be connected in right polarity or the cell or charger may damage. The IC also has a temperature input pin from which we can connect a temperature sensor NTC type. The temperature sensor must be attached with the body of the battery to detect the temperature of the battery while charging. The IC is also programed to disconnect the charging when the battery temperature goes above from a limit set inside the IC’s program. The module is also having two indicators LEDs also marked in the module pinout & details above. One LED indicates the battery charging in progress and when the battery become full charged it automatically gets deactivated and the another LED will become activated to indicate that the battery is fully charged. It is a tiny module with all the components mentioned in the above circuit diagram. If you notice, there is a Micro USB connector at the input side of the board. Using this, you can charge a Li-Ion battery from an USB source. Almost all the electronic devices and gadgets run on battery power now-a-days. You can find many devices like Mobile Phones, Tablets, Laptops, Cameras, etc. that run on battery.

This chip will not activate for battery voltage level problems (unless the TP4056 fails) since the TP4056: Outputs negative voltage from USB cable for charging battery. It should be connected to negative of the battery Over-discharge protection feature which prevents the battery from being discharged below 2.4V by cutting off output power until the battery is recharged above 3V. Using TP4056 module is very simple for providing input power to the circuit you can use a 5V 2A charger or you can also connect it with any USB outlet. Alternatively you can also connect a 5V 2A supply with the input terminals of the module. These two LEDs indicate the status of charging. When a battery is charging, Red LED glows, and when it is fully charged, the Green LED turns on. TP4056 FeaturesBAT: It is the battery connection pin connected to the positive terminal of the battery. The voltage at this pin is 4.2V. PROG: The charge current to the battery is set by connecting a Resistor called R PROG between this pin and GND. Based on the value of the resistor, the charge current can be anywhere from 130mA to 1000A. Once the module charges the Lithium battery completely, it will automatically stop charging and the Red LED will turn off and the Green LED will turn ON to indicate the completion. Now the circuit can be connected to the Circuit (Load) which has to be powered by this battery as shown in the pin diagram above. The module will monitor the voltage of the battery as its being consumed by the circuit (load). When it goes below the critical value (3.7V) the module will automatically disconnect your battery form the load and protect your battery from over discharge. CHRG: When the battery is charging, this pin is pulled low. An LED is connected to this pin to indicate battery charging. So If you are looking for a module using which you can safely use your Lithium battery for both charging it and for connecting it to your circuit, then this module could be the right choice for you.

Apart from the small devices mentioned above, Cars, Motorcycles, electric vehicles also contain battery and require a battery charger mechanism. As mentioned earlier, the PROG (Pin 2) is used to control the charge current to the battery. It is controlled with the help of a resistor called R PROG. The following table shows a list of charging current values for the corresponding R PROG values. Lithium-ion battery charging and discharging module which supports a constant current – constant voltage charging mechanism.Otherwise, there are connectors for Input Voltage as well as terminals for connecting the Battery. The R PROG resistor on this module is of 1.2KΩ. Hence, this module supports a 1A (1000mA) charging current. CE: It is an input pin for enabling the chip into operation or disabling it. When a HIGH input is given, the TP4056 is in normal mode and when a HIGH input is given, the IC is disabled. The charging current is 1A and it is adjustable. You can change it by connecting a resistor of 1kΩ at IN- pad. NOTE: This module and the circuit shown above doesn’t include the temperature measurement. Charging an 18650 Lithium Ion Battery with TP4056 The TP4056 is a low-cost Lithium Ion battery charger controller IC. It supports a constant current – constant voltage charging mechanism for s single cell Li-Ion Battery.