PROPER CHARGING TECHNIQUES ARE EXTREMELY IMPORTANT IF A USER EXPECTS TO OBTAIN LONG BATTERY LIFE OVER MANY DISCHARGE-CHARGE CYCLES. METHODS OF CHARGING SUCH BATTERIES ARE DESCRIBED, EMPHASIZING THE CHARGING METHODS FOR SEALED SECONDARY BATTERIES, PARTICULARLY SEALED NICKEL-CADMIUM TYPES. THE ADVANTAGES AND DISADVANTAGES OF VARIOUS COMMONLY USED CHARGING SYSTEMS ARE NOTED. FASTCHARGE SYSTEMS ARE ALSO DISCUSSED, STRESSING WAYS OF DETERMINING WHEN A FULL CHARGE ON THE BATTERY HAS BEEN ATTAINED. THE AUTHOR CONCLUDES WITH A LIST OF APPROVED PRACTICES AND RECOMMENDATIONS FOR THE USE OF NICKELCADMIUM BATTERIES. THIS BOOKLET WILL SERVE AS A HANDY REFERENCE GUIDE FOR USERS OF RECHARGEABLE BATTERIES AND CHARGING SYSTEMS. FOR INFORMATION RELATING TO THE PERFORMANCE CAPABILITIES OF DIFFERENT TYPES OF BATTERIES AND GUIDELINES FOR DETERMINING THE TYPE OF BATTERY TO USE IN A GIVEN PIECE OF EQUIPMENT, SEE NCJ-07031, BATTERIES USED WITH LAW ENFORCEMENT COMMUNICATIONS EQUIPMENT, COMPARISON AND PERFORMANCE CHARACTERISTICS. (SNI ABSTRACT)