Abstract: A battery comprising an electrode stacked body that includes a plurality of electrodes and a plurality of separators that are alternately stacked; and a film-made cover member that, by joining mutually overlapped peripheral portions of films, constitute a package for hermetically receiving therein the electrode stacked body, in which the plurality of separators include separators that are flat in shape and larger in size and separators that are flat in shape and smaller in size, and the separators that are flat in shape and larger in size project outward from a side of the electrode stacked body and joined to the films of the film-made cover member at a position inside the mutually joined peripheral portions of the film-made cover member.

Abstract: A positive electrode material for a lithium secondary battery includes a lithium manganese oxide having a spinel structure, expressed by one of the general formulae; LixMnyO4 (where 1≦x≦1.33 and 3−x<y≦3.1−x); and LixMnyMzO4 (where M is a metallic element other than Li and Mn, 1≦x≦1.33, 3−x−z<y≦3.1−x−z, and o<z≦1.0). The metallic element M may be at least one selected from the group consisting of Mg, Al, Cr and Ni. A lithium secondary battery includes at least a positive electrode of the positive electrode material.

Abstract: A battery set and a method for producing electric power output are disclosed as including a plurality of groups (A, B) of series-connected battery cells, wherein each group produces a voltage of x [V] in a normal state and a voltage of y [V] in an overcharged state and wherein each group includes more than y/(y−x) pieces and less than 400/x pieces of battery cells (12a, 12b, 12c, 12n; 14a, 14b, 14c, 14d, 14n) which are connected in series, and the plurality of groups of the series-connected battery cells are connected in parallel. Preferably, the battery set includes plural groups of more than four pieces of LiMn2O4 type lithium ion battery cells which are connected in series, with the plural groups being connected in parallel.

Abstract: A battery set and a method for producing electric power output are disclosed as including a plurality of groups (A, B) of series-connected battery cells, wherein each group produces a voltage of x [V] in a normal state and a voltage of y [V] in an overcharged state and wherein each group includes more than y/(y−x) pieces and less than 400/x pieces of battery cells (12a, 12b, 12c, 12n; 14a, 14b, 14c, 14d, 14n) which are connected in series, and the plurality of groups of the series-connected battery cells are connected in parallel. Preferably, the battery set includes plural groups of more than fourpieces of LiMn2O4 type lithium ion battery cells which are connected in series, with the plural groups being connected in parallel.

Abstract: A lithium ion secondary battery comprises a non-aqueous electrolytic solution, and a current collector which is coated with an active material and immersed in the electrolytic solution. By setting the coating thickness of said active material 5-80 &mgr;m, the power density of the lithium ion secondary battery is improved.

Abstract: A cell which has become inactive is detected in a multi-cell battery (15) comprising plural cells (Cn). An inactivity detecting circuit comprising a signal generator (Dn1) and a diode (Dn2) connected in series, is connected in parallel with the cell (Cn) When the cell becomes inactive, the signal generator (Dn1) emits a signal to indicate the state of the cell. Hence, it is possible to economically detect loss of cell activity.

Abstract: A positive electrode material for a lithium secondary battery includes a lithium manganese oxide having a spinel structure, expressed by one of the general formulae; LixMnyO4

Abstract: This invention relates to a lithium ion multi-cell battery (15) wherein plural lithium ion cells (C.sub.n) are arranged in series. Each cell comprises a positive electrode of manganese/spinal oxide and a negative electrode. A first Zener diode (Z.sub.n 1) and first resistor (R.sub.n 1) are connected in series between the electrodes. By setting the Zener voltage (VZ1) of the first Zener diode (Z.sub.n 1) equal to the cell voltage VL of the responding cell (C.sub.n) when positive electrode crystal phase transport stars in that cell (C.sub.n), the charge amount of each cell is made uniform.

Abstract: A state of charge indicator of a lithium ion battery computes a state of charge (SOC) corresponding to a cell open circuit voltage from a SOC-cell open circuit voltage characteristic map, and displays the SOC on a display device. Herein, the SOC-cell open circuit voltage characteristics are obtained by defining the battery charge amount when the open circuit voltage of the cell is 3.9 V as SOC=100%, and defining the battery charge amount when the open circuit voltage of the cell is 3.5 V as SOC=100%. By defining SOC=100% and SOC=0% in this way, the SOC can be correctly computed and displayed even if the battery has deteriorated.

Abstract: An inductor (L), capacitor (C) and alternator (OSC) are connected in series to the positive and negative poles of a battery (15). The temperature of the battery (15) is increased by causing the alternator (OSC) to generate an alternating current having the resonance frequency of the inductor (L) and capacitor (C). The alternating current is consumed by the internal resistance of the battery (15) due to the resonance of the inductor (L) and capacitor (C), and the temperature of the battery (15) therefore rises due to the heat thereby generated in the battery. In this way, the temperature of the battery (15) can be effectively increased with minimum power consumption.