CST Level 1 Land Surveyor Certification Practice

Why is it generally recommended to fully discharge most NiCad batteries before recharging?

1. To prevent leaking

2. Variability of electrical current

3. To avoid developing "memory"

4. To maintain consistent voltage

The correct answer is: To avoid developing "memory"

NiCad batteries, or nickel-cadmium batteries, are known for a phenomenon often referred to as "memory effect." This effect occurs when a battery is repeatedly charged after being only partially discharged. If this happens, the battery can "remember" the smaller capacity, which leads to a reduction in the usable capacity over time. Essentially, the battery begins to think its full charge is the level it last reached before recharging, instead of its actual capacity. By discharging NiCad batteries fully before recharging, users can help ensure that the entire capacity of the battery can be accessed and maintained. This practice helps prevent voltage drop during use and preserves the overall health and longevity of the battery by ensuring that it is able to hold and deliver its full charge. Other factors such as leaking or variability in electrical current are not the primary reasons for fully discharging NiCad batteries before recharging. Instead, the goal is to maintain the battery’s ability to hold its full charge, which is directly impacted by the discharge-recharge cycle involving the memory effect.