I have been working on motorising my bicycle using a geared DC motor and now I need a battery pack for that. So to make a battery pack I have decided to go with the popular 18650 lithium ion cells from two old hoverboard batteries.
Since the cells are from used batteries so I need to balance charge all the cells before making the battery pack. Everytime I use these 18650 cells I need to go through this stage when I need to balance charge all the cells individually to get them at the same potential.
Now to get through efficiently I decided to built a dedicated charger for 18650 cells. Moreover, I have decided to make it a modular charger so that I can add up modules to form a larger grid that enables me to charge as many cells as I want simultaneously.”

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