Battery and battery manufacturing method

A battery, comprising:

• a first current collector;
• a first electrode layer;
• a first counter electrode layer;
• and
• a second electrode layer,
• wherein the first counter electrode layer is a counter electrode of the first electrode layer and the second electrode layer,
• wherein the first current collector includes a first electroconductive portion, a first insulating portion, and a second electroconductive portion,
• wherein the second electroconductive portion includes a first edge region, a first front face region, a first rear face region, a first fold portion, a second front face region, a second rear face region, and a second edge region,
• wherein the first front face region is a region situated between the first edge region and the first fold portion,
• wherein the first rear face region is a region situated on a rear face of the first front face region,
• wherein the second front face region is a region situated between the second edge region and the first fold portion,
• wherein the second rear face region is a region situated on a rear face of the second front face region,
• wherein the first current collector is folded at the first fold portion, whereby the first rear face region and the second rear face region are positioned facing each other,
• wherein the first electrode layer is disposed in contact with the first electroconductive portion,
• wherein the first counter electrode layer is disposed in contact with the first front face region,
• wherein the second electrode layer is disposed in contact with the second front face region,
• wherein the first insulating portion links the first electroconductive portion and the first edge region,
• wherein the first current collector is folded at the first insulating portion, whereby the first electrode layer and the first counter electrode layer are positioned facing each other, and
• wherein the first current collector is folded at the first fold portion such that the first rear face region faces and is in contact with the second rear face region and conducts electricity causing electron mobility in the first fold portion.