Pulsar Developments Ltd - NiCad / NiMH Battery Packs

NiCad / NiMH Battery Packs

We can duplicate any battery sample which you provide or alternatively a new pack can be designed.

It is good practice to incorporate over-temperature cut-outs and perhaps current limiting devices within the pack for safety reasons. Advice is available based upon the operating temperature range current drain and your other design criteria.

It is possible to combine NiCad or NiMH cells into any arrangement to create a battery pack. To create a useful drawing for us to work from there a few easy steps to follow.

Calculate your requirements in terms of Voltage and Capacity
Using the fact that each cell has a nominal voltage of 1.2V, calculate how many cells need to linked in series to achieve your overall Voltage requirement
Your design must use similar sized cells (otherwise current considerations become problematic). Unlike voltages, capacities do not add up when cells are joined in series. This gives you two options for obtaining your desired capacity
1. Choose a cell size that is sufficiently large
2. You can put similar series arrangements of cells in parallel, thereby adding capacity
From the previous steps you should now know how all the cells will be connected. You can now arrange them into a pack and sketch their layout

Example 1

1. I need a small 7.2V 1300mAh battery pack

2. 7.2V / 1.2V = 6 cells

3. Looking at the table on the previous webpage I can see that the AA or the 4/5 A cells have a high enough capacity. One of my requirements was a small pack so I shall choose the AA cells for lower overall volume

4. Either of the following configurations would work but the second suits my application better