TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Properties: The moisture absorption material is equipped with a space for absorbing actively the moisture content which trespasses inside the cladding material. The moisture absorption material comprises supports radially extended from the gravity center position, and a peripheral portion connecting the supports. A circular or square hole is formed for penetration of the moisture absorption material. A hollow portion is formed at the surface of the moisture absorption material. The bottom face of the hollow portion is ball-shaped or square-shaped. The moisture absorption material is provided with a slit extending inside from the periphery. The size of the moisture absorption material is such that it includes the outer-edge portion of the battery element. The battery element has a laminate of dipolar electrode.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Materials: The moisture absorption material consists of synthetic zeolite, silica gel, phosphorus pentaoxide, barium oxide, or calcium oxide. The material couples a moisture absorption material powder with a binder. A lithium-transition-metal complex oxide is used as an active material which forms the anode layer. Carbon or lithium-transition-metal complex oxide is used as an active material which forms the cathode layer.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Materials: The moisture absorption material consists of synthetic zeolite, silica gel, phosphorus pentaoxide, barium oxide, or calcium oxide. The material couples a moisture absorption material powder with a binder. A lithium-transition-metal complex oxide is used as an active material which forms the anode layer. Carbon or lithium-transition-metal complex oxide is used as an active material which forms the cathode layer. EXAMPLE - A gel electrolyte was produced using a copolymer of polyethylene oxide and polypropylene oxide, a pre-gel solution consisting of polycarbonate and ethylene carbonate, and a lithium compound (Li(C2F5SO2)2N). Ground synthetic zeolite was dry-blended with pellets of high-density polyethylene, and heat-pressed at 200degreesC to obtain a moisture absorption material. A battery element was produced by laminating an anode and a cathode on both sides of the gel electrolyte. The moisture absorption material was interposed between both surfaces of the battery element, and sealed with aluminum lamination. The vacuum sealing of the aluminum lamination was carried out by heat-fusion, to obtain a lithium secondary battery. The battery had a capacitance maintenance factor of 91% after waterproof test, and 98% after vibration-resistance test.