Nickel cadmium (NiCad) batteries are the first common battery type in notebook computers, and they may still be used in earlier notebook computers. Large bag type and open type nickel cadmium batteries are mainly used as starting or emergency power supply for railway locomotives, mines, armored vehicles, an aircraft engine, etc. Cylindrical sealed nickel cadmium battery is mainly used for portable electrical appliances such as electric tools and shavers. Small button nickel cadmium batteries are mainly used for cordless phones and electric toys with low current and low rate discharge. Due to the environmental pollution caused by waste nickel cadmium batteries, this series of batteries will gradually be replaced by nickel metal hydride batteries with better performance.

The most fatal disadvantage of nickel cadmium battery is that if it is not handled properly in the process of charging and discharging, there will be a serious "memory effect", which will greatly shorten the service life. The so-called "memory effect" is that the battery is not fully discharged before charging. Over time, it will reduce the battery capacity. In the process of battery charging and discharging (discharge is more obvious), some small bubbles will be generated on the battery plate. The accumulation of these bubbles over time reduces the area of the battery plate and indirectly affects the capacity of the battery. Of course, we can reduce the "memory effect" by mastering reasonable charging and discharging methods. In addition, cadmium is toxic, so nickel cadmium battery is not conducive to the protection of ecological environment. Therefore, in the import and export sales of nickel cadmium batteries, it is more necessary to test according to international standards in order to grasp the trend of the market.