NiCAD battery charger

[Noman Yousaf]

i want to know about some questions about NiCAD batteries
1: how can we know that battery cell of 1.2v is charged fully. how much voltage
will be when it is charged fully.
2: how can we calculate the value of resistor in series of cell to charge it completly
3: does rapid charge, reduce the life of battery?
any site which has circuits and theory of these types of batteries


Thanks in advance

 

[electronicus]

Look the link: https://www.ni-cd.net/accusphp/index2.php

 

[pavcostel]

1: how can we know that battery cell of 1.2v is charged fully. how much voltage
will be when it is charged fully.

Usually, when is full charger the cell had around 1,4Volts. Also, for NiMh and NiCd cells is used most of the time the "delta peak" detection, or fixed time at low C, around 0,1C.

does rapid charge, reduce the life of battery

I can tell you only that: I use this kind of cells in Hobby R/C. It is certain that this application and fast charge process make the life very short for those cells. But I charge around 1,5C to 2C, depend on the need I have. If you mean "fast charge" under 1C, I think it will be not such big problem. Also I use till 20C at discharge, even that is toxic for the life of cells.
So, please be more specific, what you intend for "fast charge", witch rate of discharge you use? The information from the producers is sometimes very confusing, because they try to protect their bussiness.

Regards,