Bipolar secondary battery

A bipolar secondary battery comprising:

• a plurality of bipolar electrodes stacked in a stacking direction, each bipolar electrode including a current collector with a first active material layer formed on a first surface of the current collector and the first active material layer having outer edges, and a second active material layer formed on a second surface of the current collector opposite the first surface and the second active material layer having outer edges;
• electrolyte layers disposed between the first active material layer and the second active material layer of immediately-adjacent pairs of bipolar electrodes of the plurality of bipolar electrodes;
• and
• seal members disposed between the current collectors of the immediately-adjacent pairs of bipolar electrodes and about an outer periphery thereof in order to prevent leakage of an electrolyte solution of the electrolyte layers;
• wherein the outer edges of the first active material layers are positioned further from a center of the battery in a planar direction than the outer edges of the second active material layers, the planar direction being perpendicular to the stacking direction of the plurality of bipolar electrodes;
• and
• wherein each of the seal members has an edge portion overlapping the outer edges of the first active material layer in the stacking direction with the current collector provided therebetween.