Patent ID: 6632565
Filing Date: 2003-10-14
Classification: H01M,Y02E,Y02P

Abstract:
A lithium secondary battery comprising:a battery case; an internal electrode body contained in the battery case and including a positive electrode comprising lithium manganese oxide, a negative electrode comprising carbonaceous material and a separator film made of porous polymer, the positive electrode and the negative electrode being wound or laminated so that the positive electrode and negative electrode are not brought into direct contact with each other via the separator film, an organic electrolyte solution comprising LiPF6 contained in the battery case, and a zeolite having a moisture absorption characteristic, which is incorporated in the battery case so that the zeolite is brought into contact with the organic electrolyte solution within the battery case, wherein the zeolite is of an aluminosilicate family having at least one structure selected from among LTA type zeolites and FAU type zeolites, wherein the zeolite is incorporated into the battery case using a means that disposes the zeolite to be contained in a bag permeable to electrolyte solution inside the battery case, whereby the zeolite absorbs moisture to reduce or prevent decomposition of LiPF6 to separate out HP, thereby reducing or preventing dissolution of manganese from the positive electrode, said battery having a self-discharge amount of 0.69% per day or less.