Abstract: A lead acid battery including: a positive electrode plate including a positive electrode grid and a positive electrode active material; a negative electrode plate including a negative electrode grid and a negative electrode active material; an electrode plate group including the positive electrode plate, the negative electrode plate, and a separator interposed between the positive electrode plate and the negative electrode plate; a battery container including a plurality of cell chambers each accommodating the electrode plate group and an electrolyte; and a lid sealing an opening of the battery container. A ratio P/N of mass P of the positive electrode active material to mass N of the negative electrode active material is 1.25 or more and 1.65 or less. The negative electrode grid contains bismuth in an amount of 1 ppm or more and 300 ppm or less.

Abstract: A lead acid battery including: a positive electrode plate including a positive electrode grid and a positive electrode active material; a negative electrode plate including a negative electrode grid and a negative electrode active material; an electrode plate group including the positive electrode plate, the negative electrode plate, and a separator interposed between the positive electrode plate and the negative electrode plate; a battery container including a plurality of cell chambers each accommodating the electrode plate group and an electrolyte; and a lid sealing an opening of the battery container. A ratio P/N of mass P of the positive electrode active material to mass N of the negative electrode active material is 1.25 or more and 1.65 or less. The negative electrode grid contains bismuth in an amount of 1 ppm or more and 300 ppm or less.

Abstract: A lead acid storage battery including: positive electrode plates each including a positive electrode grid and a positive electrode active material, and negative electrode plates each including a negative electrode grid and a negative electrode active material. The positive and negative electrode plates are stacked alternately with a separator therebetween to form an electrode plate group. The battery further includes: a battery container having cell chambers each containing the electrode plate group and electrolyte, and a cover sealing an opening of the battery container. The positive electrode active material has a pore distribution having a peak in region A from 0.03 ?m to 0.1 ?m and a peak in region B from 0.2 ?m to 1.0 ?m, and a ratio AM/BM of peak AM in region A to peak BM in region B is 0.34 or more and 0.70 or less. The negative electrode grid contains bismuth in an amount of 1 ppm or more and 300 ppm or less.

Abstract: A lead acid battery including: a positive electrode plate including a positive electrode grid and a positive electrode active material; a negative electrode plate including a negative electrode grid and a negative electrode active material; an electrode plate group including the positive electrode plate, the negative electrode plate, and a separator interposed between the positive electrode plate and the negative electrode plate; a battery container including a plurality of cell chambers each accommodating the electrode plate group and an electrolyte; and a lid sealing an opening of the battery container. A ratio P/N of mass P of the positive electrode active material to mass N of the negative electrode active material is 1.25 or more and 1.65 or less. The negative electrode grid contains bismuth in an amount of 1 ppm or more and 300 ppm or less.

Abstract: In a lead-acid battery including an electrode plate group housed in a cell chamber 6 with an electrolyte, each positive electrode plate includes a positive electrode grid made of lead or a lead alloy containing no antimony, and a positive electrode active material with which the positive electrode grid is filled. Each negative electrode plate includes a negative electrode grid made of lead or a lead alloy containing no antimony, a surface layer formed on a surface of the negative electrode grid and made of a lead alloy containing antimony, and a negative electrode active material with which the negative electrode grid is filled. A mass ratio MN/MP falls within a range of 0.70 to 1.10, where MP represents the mass of the positive electrode active material per cell chamber, and MN represents the mass of the negative electrode active material per cell chamber.

Abstract: In the storage battery system, from the same temperature and the same voltage as both batteries a decrease per day of an open-circuit voltage of the lead-acid storage battery by a self-discharge is ?V1(V/day) and a decrease per day of an open-circuit voltage of the sub-battery by a self-discharge is ?V2(V/day), and a relation of ?V1??V2 is satisfied. The sub-battery is a nickel hydride storage battery.

Abstract: In a lead-acid batter including an electrode plate group housed in a cell chamber with an electrolyte, each positive electrode plate includes a positive electrode grid made of lead or a lead alloy containing no antimony, and a positive electrode active material with which the positive electrode grid is filled. Each negative electrode plate includes a negative electrode grid made of lead or a lead alloy containing no antimony, a surface layer formed on a surface of the negative electrode grid and made of a lead alloy containing antimony, and a negative electrode active material with which the negative electrode grid is filled. A mass ratio MN/MP falls within a range of 0.70 to 1.10, where MP represents the mass of the positive electrode active material per cell chamber, and MN represents the mass of the negative electrode active material per cell chamber.

Abstract: A lead-acid battery grid used for an electrode of a lead-acid battery, wherein the lead-acid battery grid is made of a Pb alloy containing at least one of Sn or Ca, and includes an upper frame constituting an upper side of the lead-acid battery grid, a lower frame constituting a lower side of the lead-acid battery grid, and a meshed part being present between the upper frame and the lower frame and including intersecting strands, a ratio Wu/W of a mass Wu of an upper half of the meshed part to a total mass W of the meshed part is 62.5% or higher and 67% or lower, and a cover layer containing a larger amount of Sn than the strands is formed on at least part of a surface of the strands, and the cover layer is not formed on a surface of the lower frame.