All of the modern electronics that we use, including smartphones, laptops, power banks, etc., use Li-Ion batteries (18650 cells). These batteries are a steady source of power and a decent backup, making them excellent for DIY projects. However, given the high cost of commercial chargers, charging these batteries is still a nuisance. For Li-Ion batteries, a high-quality charger is also necessary; otherwise, the battery life would be shortened quickly. While a balanced charger is more expensive, it does the job well.
As a result, I made a Li-Ion battery charger for this tutorial that can charge four 18650 cells at once. By cutting off electricity to the individual cells once the battery has fully charged, this charger, which is incredibly easy to construct, accomplishes the task of a balanced charger.
Components Required
- General Purpose PCB Board
- TP4056 Module
- Office Paper Clips
- Header Pins
- PCB Switch
- 3.7v Li-Ion Battery
- Soldering Iron
Let’s Begin
- Place the batteries on top of the general-purpose PCB board.
- On the PCB board, make a mark indicating the width and distance between the battery edges. (If the PCB board is large, it is simple to cut it to size.)
- As seen in the image above, unfold 8 office paper clips, then cut them from the edges with pliers.
- Depending on how many batteries need to be charged, a total of 8 U-clips need to be produced.
- So that the batteries may be placed between the U-clips, place them on the PCB board.
- The battery holders will be the clips.
- Additionally, create the side rails using the remaining section from the clips.
- As seen in the picture, thoroughly solder the clips onto the PCB board. Be careful during soldering to prevent the clips from connecting to one another.
Add the Components
- Put a TP4056 charging module where it is indicated in the above image on the PCB board.
- Mark the module’s holes on the PCB board with a marker.
- For each of the designated holes, solder a header pin.
- Carefully solder the module after placing it over the header pins.
- Use one module per battery, or the same number of modules as there are batteries to be charged.
- As illustrated in the picture, solder each module to the PCB board.
- Solder a switch made from PCB switches between each module on the PCB board.
Connect the Components
- Solder all the components together while keeping in mind the connection layout shown above.
- Be sure to mark the polarity on the U-clip battery holder.
- In accordance with the polarity, connect the battery holder terminals to the input terminals of the TP4056 charging module.
- So that each module can get electricity from a single wall charger, connect the modules together.
- Additionally, connect the switches so that each one can independently regulate the electricity going to the modules.
Test the Battery Charger
- Placing the batteries in the holder over the PCB board is a good idea.
- Switch on the power and attach a mobile phone charger to one of the modules.
- The module’s indicator will illuminate to show that it is charging.
- Control the power delivered to the batteries using the switches.
- If you simply want to charge one battery, turn all the switches OFF.
- Switches for the number of batteries charging at a specific time should be turned ON.
- Since each battery has its own charger, the issue of overcharging and undercharging never arises (most common problem that damages Li-ion cells)
Note: A TP4056 charging module has a 1A at 5v output capacity. Since I created a 4 battery charger, I must use a 2A mobile charger to ensure that each cell receives at least 500mA.
Hope you find this project simple. Superkitz will be back soon with more informative blogs. Thank You Bye.
