1. Introduction
Li-ion batterieswere brought onto the consumermarket by Sony
Corp. in the early 1990s [1]. Desirable characteristics, such as high
energy density, low auto-discharge rate, and high potential dif-
ference, made these batteries preferable to the typical Ni–Cd and
Ni–MH batteries for many applications. Moreover, Li-ion batter-
ies are less harmful to the environment. For Li-ion batteries, the
main materials used are LiCoO2 in the cathode and carbon in the
anode [2]. High potentials obtained with these batteries (approxi-
mately 3.70V) hinder the utilization of aqueous electrolytes so that
a mixture of lithium organic solvents and inorganic salts is usually
required.