Stack, electrode structure, battery, flight vehicle, method for producing stack, and method for producing electrode structure

An electrode structure comprising:

• a first electrode and a second electrode;
• a third electrode and a fourth electrode;
• and
• a first separator, a second separator, and a third separator,
• wherein the first electrode, the first separator, the third electrode, the second separator, the second electrode, the third separator, and the fourth electrode are stacked in this sequence,
• each of the first electrode and the second electrode has:
• a current collector;
• and
• an active material layer arranged on at least one face of the current collector,
• the current collector includes:
• a support layer including a thermoplastic resin material;
• and
• a first metal layer and a second metal layer formed on both faces of the support layer,
• in a vicinity of an end of the first electrode and the second electrode, the first metal layer and the second metal layer of the first electrode as well as the first metal layer and the second metal layer of the second electrode are integrated by welding,
• the current collector has a region in which a plurality of through-holes extending through the current collector are formed in a vicinity of an integrated region, which is a region in which the first metal layer and the second metal layer are integrated by welding,
• a circular equivalent diameter of the plurality of through-holes is from 15 μm to 150 μm, and
• an interval of two adjacent through-holes among the plurality of through-holes is from 30 μm to 250 μm.

A method for producing a stack, comprising:

• preparing a welding target including a support layer including a thermoplastic resin material as well as a first metal layer and a second metal layer formed on both faces of the support layer;
• stacking a plurality of welding targets, each of which is identical to the welding target;
• softening the resin material of a softened region arranged in a part of the plurality of welding targets by applying energy to the softened region;
• pressing a welded region arranged in at least a part of the softened region;
• and
• welding the first metal layer and the second metal layer of the plurality of welding targets by applying current and/or voltage to the welded region, which has been pressed,
• wherein the first metal layer and the second metal layer of each of the plurality of welding targets are electrically connected,
• a plurality of through-holes extending through the support layer, the first metal layer, and the second metal layer are formed in at least a part of the softened region of each of the plurality of welding targets,
• a circular equivalent diameter of the plurality of through-holes is from 15 μm to 150 μm,
• an interval of two adjacent through-holes among the plurality of through-holes is from 30 μm to 250 μm, and
• the pressing includes:
• applying pressure to the plurality of welding targets that have undergone the stacking so that the resin material that has undergone the softening flows into at least a part of through-holes;
• and
• bringing the first metal layer and the second metal layer of each of the plurality of welding targets close to each other to a distance that allows welding.

A method for producing an electrode structure, comprising preparing a first electrode and a second electrode;

• preparing a third electrode and a fourth electrode;
• preparing a first separator, a second separator, and a third separator;
• stacking the first electrode, the first separator, the third electrode, the second separator, the second electrode, the third separator, and the fourth electrode in this sequence;
• and
• welding a part of the first electrode and the second electrode,
• wherein each of the first electrode and the second electrode includes:
• a current collector;
• and
• an active material layer arranged on at least one face of the current collector,
• the current collector includes:
• a support layer including a thermoplastic resin material;
• and
• a first metal layer and a second metal layer formed on both faces of the support layer,
• the first metal layer and the second metal layer are electrically connected,
• a plurality of through-holes extending through the support layer, the first metal layer, and the second metal layer are formed in at least a part of a softened region arranged in a part of the current collector,
• a circular equivalent diameter of the plurality of through-holes is from 15 μm to 150 μm,
• an interval of two adjacent through-holes among the plurality of through-holes is from 30 μm to 250 μm,
• the welding a part of the first electrode and the second electrode includes:
• stacking the current collector of the first electrode and the current collector of the second electrode;
• softening the resin material of the softened region by applying energy to the softened region of the current collector;
• pressing a welded region arranged in at least a part of the softened region;
• and
• welding the first metal layer and the second metal layer of the current collector of each of the first electrode and the second electrode by applying current and/or voltage to the welded region that has been pressed, and
• the pressing includes:
• applying pressure to current collectors that have undergone the stacking, each of which is identical to the current collector, such that the resin material that has undergone the softening flows into at least a part of a through-hole;
• and
• bringing the first metal layer and the second metal layer of each of the current collectors that have undergone the stacking close to each other to a distance that allows welding.