A new, reliable and easily implemented NiCd/NiMH battery state estimation method

This paper presents a new and reliable battery state estimation method for Ni-Cd and Ni-MH batteries used in portable applications. The proposed method performs the following two basic functions. The first one determines battery state, detecting deteriorated batteries. The second one guarantees a safe fast-charge without negative effects on battery life, analyzing the previous charge state of the battery. Due to this easily implemented method, effective and universal NiCd/NiMH battery fast-chargers can be obtained by using few and inexpensive components.