20 Among the rechargeable batteries, the NiCd remains a popular choice for applications such as portable radios, cell phones, laptop computers, video cameras, data loggers and power tools. There is a renewed interest in this chemistry and many equipment manufacturers are switching back to the NiCd after having recognized the limitations of other chemistries. Some of the distinct advantages of the NiCd over other battery chemistries are:

• Fast and simple charge.
  
• High number of charge-discharge cycles (if properly maintained, the NiCd provides several thousand cycles).
  
• Excellent load performance, even at cold temperatures.
  
• Simple storage and transportation (the NiCd is accepted by most air freight companies).
  
• Easy to recharge after prolonged storage.
  
• Forgiving if abused.
  
• Economical price.
  

The NiCd is a strong and reliable worker; hard labor poses no problem. It prefers fast charge over slow charge, and pulse-charge over DC charge. Improved performance is achieved by interspersing discharge pulses between charge pulses. Commonly referred to as burp or reverse load charge, this charge method promotes the recombination of gases generated during fast-charge. The result is a cooler and more effective charge than with conventional DC chargers. The battery is stimulated while charging, a function that improves battery performance. Research has shown that reverse load adds 15% to the life of the NiCd battery.

The NiCd does not like to be pampered by sitting in chargers for days and being used only occasionally for brief periods. In fact, the NiCd is the only battery type that performs best if periodically discharged to one volt per cell (full discharge). All other chemistries prefer shallow discharges. So important is this periodic full-discharge that, if omitted, the NiCd gradually loses performance due to crystalline formation, also referred to as memory.