This website will help the surveyor using Ni-Cd batteries to understand some of the reasons for their premature battery failure. You will also be surprised to learn - what the battery industry is reluctant to admit - that an average of 60% to 70% of discarded batteries can be revived to full service when using basic exercise and recondition methods. In other words, many of the survey batteries under two years old will meet this criteria. more... See more text