How to Build a NiCad Battery Pack

A NiCad battery is an abbreviation for Nickel-Cadmium batteries. The NiCad battery is a rechargeable battery which uses cadmium and nickel hydroxide as its electrodes. Nowadays, the battery packs in many electronic gadgets are quite costly to replace. Sometimes these packs are either unavailable in the market or are quite problematic to find. You can save money and time by making these battery packs yourself. Just follow the simple steps described below.

Tools and Materials Required

  • Blow dryer
  • Heat shrink (a tube that shrinks in diameter when heated)
  • Wires of lead
  • Battery strips made of Nickel
  • NiCad Cells that are rechargeable
  • Spot welder
  • Voltmeter

Step 1 – Determination of Voltage

To know how much power is required for your application, find out the voltage needed. You can find this out either by finding the inscription on the back of the appliance you want to run or by using an easily available digital voltmeter to measure the input and output voltages. Once that is done, buy 1.2 volt NiCad cells that can be recharged. For instance, if you are building up a battery pack of 12 volts, you will need (12/1.2 =) 10 cells. Use the Internet or skim through your local market to find the best quality cells at the best price.

Step 2 - Arranging the Cells

Before using the spot welder on the cells, it is essential to considered the topology of the battery pack. You may want it to be in a ladder, F-type, linear or radial fashion. Remember that the cells make up the battery pack. They may be piled together in a center cubic packing, alternate long and short rows packing, nested packing or arranged in any other way that suits the arrangement required. The choice is yours to make. Research on the voltage requirement of the appliance and choose the arrangement that will add to an optimized design for the battery pack.

Step 3 – Connecting the Positives with the Negatives

Now, use a spot welder to place the nickel strips between cells in such a way that the positive end of one cell connects to the negative end of the other. This will lead to a combination of voltage of all the cells. If the cells are even in number, the strips will come off the top. If the cells are odd in number, the strips will come one off the bottom and the other off the top.

Step 4 – Using Lead Wiring

Now use the spot welder to weld lead wiring to the negative and positive of the cells next to each other. Do it in pairs.

Step 5 – Inserting the Cells in a Heat Shrink Tubing

After the cells have been welded together with the help of lead wiring and spot welder, put them in the heat shrink tubing. Now use a blow dryer and blow dry the heat shrink in such a way that it shrinks around the batteries. The shrink tubing will snug the cells together and this step will lead to the completion of building a NiCad battery pack.