Lead-acid battery

A lead-acid battery comprising:

• a container;
• a partition wall which forms a plurality of cell chambers by partitioning the container;
• a plurality of elements each of which is accommodated in each of the plurality of cell chambers;
• an electrolyte solution accommodated in the plurality of cell chambers respectively;
• and
• a lid which closes opening portions of the plurality of cell chambers,
• wherein
• each of the elements includes a plurality of positive electrodes, a positive electrode shelf which connects the plurality of positive electrodes parallel to each other, a plurality of negative electrodes, a negative electrode shelf which connects the plurality of negative electrodes parallel to each other, and a separator which is interposed between the positive electrode and the negative electrode disposed adjacently to each other,
• the plurality of positive electrodes include a positive active material, a positive electrode grid portion which carries the positive active material, and a positive electrode lug portion which is integrally formed with the positive electrode grid portion for connecting the positive electrode to the positive electrode shelf,
• the plurality of negative electrodes include a negative active material, a negative electrode grid portion which carries the negative active material, and a negative electrode lug portion which is integrally formed with the negative electrode grid portion for connecting the negative electrode to the negative electrode shelf,
• the positive electrode shelf of one of two said elements accommodated in the respective cell chambers disposed adjacently to each other and the negative electrode shelf of the other element are electrically connected to each other through a penetrating connection body penetrating the partition wall,
• the penetrating connection body includes a positive electrode side member continuously formed with the positive electrode shelf and a negative electrode side member continuously formed with the negative electrode shelf, and the positive electrode side member and the negative electrode side member form a welded portion filled in a penetration hole formed in the partition wall and are brought into close contact with a periphery of the penetration hole,
• a distance A between upper end surfaces of the positive electrode shelf and the negative electrode shelf and a lower end portion of the penetration hole is set to 3 mm to 5 mm,
• a distance B between an upper end portion of the penetration hole and an upper end portion of the penetrating connection body is set to 3 mm to 5 mm,
• a distance C between the upper end portion of the penetrating connection body and a level of the electrolyte solution is set to 0 mm or more, and
• a height of the positive electrode grid portion and the negative electrode grid portion is set to 100 mm or more.