To make the battery pack, you have to first finalize the nominal voltage and capacity of the pack. Either it will be in terms of Volt, mAh/ Ah, or Wh. You have to connect the cells in parallel to reach the desired capacity (mAh ) and connect such parallel group in series to achieve the nominal voltage (Volt ).
To make the battery pack, you have to connect the 18650 cells together by means of Nickel strips or thick wire. Generally, Nickel strips are widely used for this. In general two types of nickel, strips are available in the market: nickel-plated steel strips and pure nickel strips. I will suggest buying a pure nickel.
In this project I will show you how to combine common 18650 Li-Ion batteries in order to create a battery pack that features a higher voltage, a bigger capacity and most importantly useful safety measures. These can prevent an overcharge, overdischarge and even a short circuit of the batteries.
Charging the Battery Pack : You can charge the battery pack by a 12.6V DC adapter like this. You can get it easily from aliexpress or eBay. Hope you enjoyed reading about my project as much as I have enjoyed building it. If you’re thinking about making your own I would encourage you to do so, you will learn a lot.
That means that it takes 16 LiFePO4 cells to make a 48V pack, and NCA/NCM only require 13 cells for 48V. However, LiFePO4 is considered the most fire-safe (sometimes found as a starter battery on small aircraft), and they also typically last about twice as long as the common NCA/NCM 18650-cell packs.
Then apply hot glue at the base of the battery compartment, then secure the battery pack. So that it will seats firmly and prevent any loss of wire connections. Finally, screw the top lids in place!