DIY Li-ion Cell Charger Using TP4056 (intelligent and simple )

The Li-ion charger circuit from one of my project (8 pin IC near to the USB port)

Li-ion cell is one of the top chemical battery in now a days. It is widely used in portable devices. It is used in mobile phones, laptops, toys, satellites etc... It is widely used because of its unique properties. It has a high energy concentration than all other cells. It has less weight, that is its energy to weight ratio is very high. It has a high current discharging capability. These capabilities make it to be the king in battery industry. But it has some problems, it is little bit more danger than other cells. Improper use cause large explosion. Physical damage, over heat, short circuit, over charge etc.. make it to be a danger one. These make fire and explosion. So a good care is needed for this cell. So here I make a circuit which intelligently charge the cell safely. This charger charge the cell at a safe current and in the safe voltage range and cut the charger from the battery when it is fully charged. Also it has a charging and fully charged indicator. It is a best circuit for Li-ion cell charger. It safely charge the Li-ion cell.

Li ion cell Characteristics

Li-ion cell characteristics

Characteristics simply means that the behavior. Here the behavior of Li-ion cell is represented by using the voltage and amount of charge in the cell. Here in the above figure indicate cell statistics. This characteristics are needed for making our charging circuit. We set the charging and cut-off voltage using this characteristics. So observe the given graphs.

Circuit Diagram

Single Li-ion cell charger circuit diagram

R2 resistor values and charging current

The  circuit diagram is given above. 

The circuit is based on the IC TP4056. It is a single Li-ion cell charger IC. It is used in all common Li-ion charging circuits. Its charging current is easily controlled by changing the resistance value. The charging current and resistance value combination is given in the figure. It is obtained from the  datasheet. It has 2 indicator which shows charging and full charging status. Its output voltage is set at 4.2 volt. When cell reaches 4.2V it detect as full charge and auto cut the cell from the power source and indicate via LED. These features protect the battery from over charging. It has only less external components. So it is very good for portable type projects. 



In future I plan to add some more features to this battery charging system and modify it into a smart battery management system. 

OK. See you next time.....