Abstract: The present invention provides a positive electrode of a nonaqueous electrolyte secondary cell which is prepared using an active substance containing a composition of LiNiaCobMcO2 (a+b+c=1;0≦c≦0.5) wherein M is at least one metal selected from among Mn, Fe, Zn, Ti, Cr, Mg, Al, Cu, or Ga and a composition of AlX(SO4)2 wherein X is at least one material selected from among Na, Rb, Cs, or NH4. This enables the secondary cell to diminish the reduction of a cell capacity when allowed to store and thus the storage characteristics of the secondary cell is improved.

Abstract: A lithium secondary battery according to the present invention includes a positive electrode in which an aluminum foil containing manganese is used as a current collector, a negative electrode, and a non-aqueous electrolyte solution formed by dissolving lithium salt in a non-aqueous solvent wherein divalent manganese salt is added to said non-aqueous electrolyte solution.

Abstract: A nonaqueous electrolyte secondary cell having a rolled-up electrode unit housed in a cell can and comprising a positive electrode and a negative electrode each formed by coating a surface of a striplike current collector with an electrode material. According to a first embodiment, the current collector of at least one of the positive electrode and the negative electrode comprises a plurality of current collector pieces 42 arranged along one direction and a PTC element 5 interconnecting each pair of adjacent current collector pieces 42. Alternatively with a second embodiment, at least one of the positive electrode and the negative electrode comprises a PTC element held between opposed faces of an uncoated portion of the current collector thereof and a base end portion of a current collector tab. The PTC element serves to prevent continuous occurrence of a current in excess of a predetermined value and realizes a high energy density.

Abstract: The lithium secondary battery of this invention uses a nonaqueous electrolyte including lithium tetrakis(pentafluorophenyl)borate as a part or whole of an electrolytic salt. As a result, the lithium secondary battery exhibits better charge-discharge cycle performance than a lithium secondary battery using a conventional lithium salt as the electrolytic salt.

Abstract: A nonaqueous electrolyte secondary cell having a rolled-up electrode unit housed in a cell can and comprising a positive electrode and a negative electrode each formed by coating a surface of a striplike current collector with an electrode material. According to a first embodiment, the current collector of at least one of the positive electrode and the negative electrode comprises a plurality of current collector pieces 42 arranged along one direction and a PTC element 5 interconnecting each pair of adjacent current collector pieces 42. Alternatively with a second embodiment, at least one of the positive electrode and the negative electrode comprises a PTC element held between opposed faces of an uncoated portion of the current collector thereof and a base end portion of a current collector tab. The PTC element serves to prevent continuous occurrence of a current in excess of a predetermined value and realizes a high energy density.

Abstract: A method is disclosed for manufacturing a nonaqueous battery which includes a negative electrode containing lithium or a material capable of occluding and discharging lithium, a positive electrode containing an oxide of manganese or cobalt, and a nonaqueous electrolyte. In the method the nonaqueous electrolyte is treated with an oxide of the metal of the positive electrode before the nonaqueous electrolyte is assembled into the battery. The method provides a nonaqueous electrolyte battery having an improved self-discharge property.