LITHIUM SECONDARY BATTERY AND BATTERY APPARATUS EQUIPPED WITH THIS BATTERY

摘要

PROBLEM TO BE SOLVED: To provide a lithium secondary battery that does not cause overcharged state and a battery apparatus equipped with this battery that does not need a protective circuit by means of this lithium secondary battery. SOLUTION: Lithium secondary battery is constituted by disposing a negative pole (e.g. graphite) that can absorb and desorb lithium ions and a positive pole using lithium-contained metal oxide (e.g. Li-contained cobalt oxide) as a substance to activate the positive pole by sandwiching a separator containing poly-vinylidene fluoride(PVdF) in between, and then by injecting a nonaqueous electrolyte. In the lithium secondary battery constituted like this, battery voltage does not rise above the rated voltage as shown in Figure 5 even when overcharged.