Abstract: A lead-acid battery includes a positive electrode plate, a negative electrode plate, an electrolyte solution, and a polymer compound, in which the positive electrode plate includes a positive current collector and a positive electrode material, the negative electrode plate includes a negative current collector and a negative electrode material, the Ca content of the positive current collector is 0.13% by mass or less, and the polymer compound has a peak in a range of 3.2 ppm or more and 3.8 ppm or less in a chemical shift of 1H-NMR spectrum, or the polymer compound contains a repeating structure of oxy C2-4 alkylene units.

Abstract: A lead-acid battery includes a positive electrode plate, a negative electrode plate, and an electrolyte solution, in which the positive electrode plate includes a positive current collector and a positive electrode material, the negative electrode plate includes a negative current collector and a negative electrode material, the positive current collector contains Sn in an amount of 0.95% by mass or more, the negative electrode material contains a polymer compound, and the polymer compound has a peak in a range of 3.2 ppm or more and 3.8 ppm or less in a chemical shift of 1H-NMR spectrum, or the polymer compound contains a repeating structure of oxy C2-4 alkylene units.

Abstract: A lead-acid battery includes a positive electrode plate, a negative electrode plate, an electrolyte solution, and a polymer compound, in which the positive electrode plate includes a positive current collector and a positive electrode material, the negative electrode plate includes a negative current collector and a negative electrode material, the Ca content of the positive current collector is 0.13% by mass or less, and the polymer compound has a peak in a range of 3.2 ppm or more and 3.8 ppm or less in a chemical shift of 1H-NMR spectrum, or the polymer compound contains a repeating structure of oxy C2-4 alkylene units.

Abstract: The organic expander in a negative electrode material of a lead-acid battery contains an S polymer having an aromatic ring and an L polymer having an aromatic ring, and a mass MS1 of the S polymer and a mass ML1 of the L polymer satisfy 0.05?ML1/(ML1+MS1)?0.15.

Abstract: A lead-acid battery includes a positive electrode plate, a negative electrode plate, and an electrolyte solution, in which the positive electrode plate includes a positive current collector and a positive electrode material, the negative electrode plate includes a negative current collector and a negative electrode material, the positive current collector contains Sn in an amount of 0.95% by mass or more, the negative electrode material contains a polymer compound, and the polymer compound has a peak in a range of 3.2 ppm or more and 3.8 ppm or less in a chemical shift of 1H-NMR spectrum, or the polymer compound contains a repeating structure of oxy C2-4 alkylene units.

Abstract: A lead-acid battery includes a positive electrode plate, a negative electrode plate, and an electrolyte solution. The negative electrode plate includes a negative electrode material. The negative electrode material contains a polymer compound, and the polymer compound has a peak in a range of 3.2 ppm or more and 3.8 ppm or less in a chemical shift of 1H-NMR spectrum. Alternatively, the negative electrode material contains a polymer compound having a repeating structure of oxy C2-4 alkylene units. A ratio: Cn/Sn of a content Cn of the polymer compound in the negative electrode material to a specific surface area Sn of the negative electrode material is 25 ppm·m?2·g or more.

Abstract: A lead-acid battery includes a positive electrode plate, a negative electrode plate, and an electrolyte solution. The negative electrode plate includes a negative electrode material. The negative electrode material contains a polymer compound. The polymer compound has a peak in a range of 3.2 ppm or more and 3.8 ppm or less in a chemical shift of 1H-NMR spectrum, or the negative electrode material contains a polymer compound having a repeating structure of oxy C2-4 alkylene units.

Abstract: A lead-acid battery provided with a negative electrode plate, a positive electrode plate, and an electrolyte solution. The negative electrode plate includes a negative current collector and a negative electrode material. When it is defined in a log differential pore volume distribution of the negative electrode material that a) a region having a pore size of 1 to 3 ?m is a P region, b) a region having a pore size of 6 to 15 ?m is a Q region, c) a maximum value of the log differential pore volume in the P region is P, and d) a maximum value of the log differential pore volume in the Q region is Q, after initial degradation, during use, or after 1220 cycles in a light-load life test in which charge and discharge of constant current discharge at 25 A for one minute and constant voltage charge at 2.47 V/cell and an upper limit current of 25 A for ten minutes are repeated at a test temperature of 75° C.

Abstract: A lead-acid battery provided with a negative electrode plate, a positive electrode plate, and an electrolyte solution. The negative electrode plate includes a negative current collector and a negative electrode material. When it is defined in a log differential pore volume distribution of the negative electrode material that a) a region having a pore size of 1 to 3 ?m is a P region, b) a region having a pore size of 6 to 15 ?m is a Q region, c) a maximum value of the log differential pore volume in the P region is P, and d) a maximum value of the log differential pore volume in the Q region is Q, after initial degradation, during use, or after 1220 cycles in a light-load life test in which charge and discharge of constant current discharge at 25 A for one minute and constant voltage charge at 2.47 V/cell and an upper limit current of 25 A for ten minutes are repeated at a test temperature of 75° C.

Abstract: The organic expander in a negative electrode material of a lead-acid battery contains an S polymer having an aromatic ring and an L polymer having an aromatic ring, and a mass MS1 of the S polymer and a mass ML1 of the L polymer satisfy 0.05?ML1/(ML1+MS1)?0.15.