Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: A negative electrode and a secondary battery including the negative electrode are provided. A plurality of projections and depressions are provided in a negative electrode active material layer and a negative electrode current collector. The plurality of projections and depressions in the negative electrode active material layer absorb expansion of the negative electrode active material and suppress deformation thereof. The plurality of projections and depressions in the negative electrode current collector suppress deformation of the negative electrode current collector caused by expansion and contraction of the negative electrode active material.

Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: A repeatedly bendable power storage device is provided. A highly reliable power storage device is provided. A long-life power storage device is provided. A repeatedly bendable electronic device is provided. A flexible electronic device is provided. The power storage device includes a positive electrode, a negative electrode, and an exterior body wrapping the positive electrode and the negative electrode. The exterior body includes a metal layer and a resin layer. The thickness of the metal layer in at least part of an outer edge of the exterior body is smaller than that in a region other than the outer edge. The exterior body has a plurality of slits in the outer edge.

Abstract: A negative electrode and a secondary battery including the negative electrode are provided. A plurality of projections and depressions are provided in a negative electrode active material layer and a negative electrode current collector. The plurality of projections and depressions in the negative electrode active material layer absorb expansion of the negative electrode active material and suppress deformation thereof. The plurality of projections and depressions in the negative electrode current collector suppress deformation of the negative electrode current collector caused by expansion and contraction of the negative electrode active material.

Abstract: A negative electrode and a secondary battery including the negative electrode are provided. A plurality of projections and depressions are provided in a negative electrode active material layer and a negative electrode current collector. The plurality of projections and depressions in the negative electrode active material layer absorb expansion of the negative electrode active material and suppress deformation thereof. The plurality of projections and depressions in the negative electrode current collector suppress deformation of the negative electrode current collector caused by expansion and contraction of the negative electrode active material.

Abstract: Silicon oxide which is an oxide containing at least silicon, in which part of silicon is replaced by boron, aluminum, or gallium, is provided.

Abstract: Although a material containing silicon attracts attention as a high-capacity negative electrode active material, it has a problem of having a large irreversible capacity at the initial charge and discharge cycle. As a negative electrode active material, a particle which is a mixture of silicon, lithium metasilicate, and lithium oxide is used. Because lithium metasilicate and lithium oxide are already contained in the particle of the negative electrode active material, a compound containing lithium and oxygen (lithium orthosilicate and lithium metasilicate), which is a cause of the irreversible capacity at the initial charge, is not generated any more. This enables a negative electrode active material with a small irreversible capacity.

Abstract: A repeatedly bendable power storage device is provided. A highly reliable power storage device is provided. A long-life power storage device is provided. A repeatedly bendable electronic device is provided. A flexible electronic device is provided. The power storage device includes a positive electrode, a negative electrode, and an exterior body wrapping the positive electrode and the negative electrode. The exterior body includes a metal layer and a resin layer. The thickness of the metal layer in at least part of an outer edge of the exterior body is smaller than that in a region other than the outer edge. The exterior body has a plurality of slits in the outer edge.

Abstract: A repeatedly bendable power storage device. A highly reliable power storage device. A long-life power storage device. A repeatedly bendable electronic device. A flexible electronic device. The power storage device includes a film, a positive electrode, and a negative electrode. The film includes a plurality of projections. A difference between the maximum height and the minimum height of a surface of the film is greater than or equal to 0.15 mm and less than 0.8 mm. The modulus of rigidity of the film is less than 6.5×109 N. The film includes a metal layer. The thickness of the metal layer is greater than or equal to 5 ?m and less than or equal to 200 ?m. The positive electrode and the negative electrode are surrounded by the film.

Abstract: Silicon oxide which is an oxide containing at least silicon, in which part of silicon is replaced by boron, aluminum, or gallium, is provided.

Abstract: A negative electrode and a secondary battery including the negative electrode are provided. A plurality of projections and depressions are provided in a negative electrode active material layer and a negative electrode current collector. The plurality of projections and depressions in the negative electrode active material layer absorb expansion of the negative electrode active material and suppress deformation thereof. The plurality of projections and depressions in the negative electrode current collector suppress deformation of the negative electrode current collector caused by expansion and contraction of the negative electrode active material.