Abstract: A structure suitable for a portable information terminal or a wearable device is provided. In addition, an electronic device having a novel structure that can have various forms is provided. It is preferable that a buffer layer which absorbs a difference in the amount of change in form be provided between adjacent film substrates which overlap with each other. As the buffer layer, a gelled resin material, a rubber resin material, a liquid material, an air layer, or the like can be used. Furthermore, an optical film such as a polarizing film or a color filter may be used as the buffer layer. A plurality of buffer layers may be provided in an electronic device.

Abstract: A wearable device needs to have a design corresponding to complicated surfaces of human bodies. Thus, an electronic device that can fit the characteristics of each individual human body after being purchased and can be worn naturally and comfortably is provided. The electronic device includes a secondary battery which can be transformed. By using a secondary battery which can be transformed, for example, a secondary battery can be efficiently placed in a narrow and elongated space in the electronic device, and the elongated secondary battery can be bent together with the electronic device. Furthermore, the weight balance of the electronic device can be easily adjusted.

Abstract: Provided is an electronic device with high portability and/or high browsability. The electronic device includes first and second support bodies, a first hinge, and a flexible display panel. The first hinge has a first rotation axis and connects the first and second support bodies to each other, and the first and second support bodies are capable of relatively rotating on the first rotation axis. The display panel includes at least first and second portions supported by the first and second support bodies, respectively; the first rotation axis and a first plane including the display surface overlapping with the first portion or a second plane including the display surface overlapping with the second portion are parallel to each other; and each of a distance between the first rotation axis and the first plane or the second plane is greater than zero.

Abstract: To provide a secondary battery that is suitable to a portable information terminal or a wearable device. To provide an electronic device having a novel structure that can have various forms and a secondary battery that fits the forms of the electronic device. The secondary battery includes a film provided with depressions or projections that can ease stress on the film due to application of external force. The sizes of the depressions or projections are different between a center portion and an end portion of the film. The end portion of the film is sealed with an adhesive layer. The depressions or projections of the film are formed by pressing such as embossing.

Abstract: A highly portable and highly browsable light-emitting device is provided. A light-emitting device that is less likely to be broken is provided. The light-emitting device has a strip-like region having high flexibility and a strip-like region having low flexibility that are arranged alternately. In the region having high flexibility, a light-emitting panel and a plurality of spacers overlap with each other. In the region having low flexibility, the light-emitting panel and a support overlap with each other. When the region having high flexibility is bent, the angle between normals of facing planes of the two adjacent spacers changes according to the bending of the light-emitting panel; thus, a neutral plane can be formed in the light-emitting panel or in the vicinity of the light-emitting panel.

Abstract: A structure suitable for a portable information terminal or a wearable device is provided. In addition, an electronic device having a novel structure that can have various forms is provided. It is preferable that a buffer layer which absorbs a difference in the amount of change in form be provided between adjacent film substrates which overlap with each other. As the buffer layer, a gelled resin material, a rubber resin material, a liquid material, an air layer, or the like can be used. Furthermore, an optical film such as a polarizing film or a color filter may be used as the buffer layer. A plurality of buffer layers may be provided in an electronic device.

Abstract: A sturdy electronic device is provided. A reliable electronic device is provided. A novel electronic device is provided. An electronic device includes a first board, a second board, a display portion having flexibility, and a power storage device having flexibility. The first board and the second board face each other. The display portion and the power storage device are provided between the first board and the second board. The display portion includes a first surface facing the power storage device. The first surface includes a first region not fixed to the power storage device. The first region overlaps with a display region of the display portion.

Abstract: A wearable device needs to have a design corresponding to complicated surfaces of human bodies. Thus, an electronic device that can fit the characteristics of each individual human body after being purchased and can be worn naturally and comfortably is provided. The electronic device includes a secondary battery which can be transformed. By using a secondary battery which can be transformed, for example, a secondary battery can be efficiently placed in a narrow and elongated space in the electronic device, and the elongated secondary battery can be bent together with the electronic device. Furthermore, the weight balance of the electronic device can be easily adjusted.

Abstract: In order to display 3D images by a parallax barrier method, a display screen and the eyes of a viewer need to have a specific positional relation. An object is to provide a display device with an extended area where the viewer can perceive 3D images with the naked eye. Attention is focused on the position of the viewer with respect to pixels provided in a display device and a mode of a parallax barrier provided between the viewer and the pixels. This leads to a structure in which the position of the viewer with respect to pixels is specified by using an ultrasonic wave to change a mode of a parallax barrier in accordance with the position of the viewer, thereby achieving the above object.

Abstract: A power storage system includes an AC/DC converter, a first control device, a power storage device, and a load. The first control device includes a measuring portion that measures the amount of power consumed by the load, a predicting portion that predicts the demand for power consumed by the load on the basis of the amount of power consumed by the load, and a planning portion that makes a charge and discharge plan of the power storage device on the basis of the demand for power predicted by the predicting portion. The power storage device includes a second control device, a DC/DC converter, a first battery cell group, and a second battery cell group. The power storage device is placed in an underfloor space surrounded by a base and a floor of a building.

Abstract: A secondary battery module capable of feeding power to a wearable device in a non-contact manner is provided. A power feeding system for an electronic device is provided. The power feeding system includes a secondary battery module and an electronic device. The secondary battery module includes a flexible secondary battery, a power sending portion for non-contact power transmission, a flexible thermoelectric power generating device, and a belt portion storing the flexible secondary battery and the flexible thermoelectric power generating device. The electronic device includes a power receiving portion for non-contact power transmission and is capable of power transmission from the power sending portion for non-contact power transmission which is included in the secondary battery module to the power receiving portion for non-contact power transmission which is included in the electronic device.

Abstract: A highly portable and highly browsable light-emitting device is provided. A light-emitting device that is less likely to be broken is provided. The light-emitting device has a strip-like region having high flexibility and a strip-like region having low flexibility that are arranged alternately. In the region having high flexibility, a light-emitting panel and a plurality of spacers overlap with each other. In the region having low flexibility, the light-emitting panel and a support overlap with each other. When the region having high flexibility is bent, the angle between normals of facing planes of the two adjacent spacers changes according to the bending of the light-emitting panel; thus, a neutral plane can be formed in the light-emitting panel or in the vicinity of the light-emitting panel.

Abstract: A novel electronic device is provided. Alternatively an electronic device of a novel embodiment is provided. An electronic device includes a ring portion and a display portion. The display portion is flexible. The display portion has a top surface and a first side surface in contact with at least one side of the top surface. The first side surface has a curved surface. The top surface includes a first display region. The first side surface includes a second display region. The first display region and the second display region are continuously provided. The electronic device is mounted such that the ring portion is in contact with a user's finger.

Abstract: A sturdy electronic device is provided. A reliable electronic device is provided. A novel electronic device is provided. An electronic device includes a first board, a second board, a display portion having flexibility, and a power storage device having flexibility. The first board and the second board face each other. The display portion and the power storage device are provided between the first board and the second board. The display portion includes a first surface facing the power storage device. The first surface includes a first region not fixed to the power storage device. The first region overlaps with a display region of the display portion.

Abstract: A novel electronic device is provided. Alternatively an electronic device of a novel embodiment is provided. An electronic device includes a support and a display portion. The support has a first curved surface. The display portion is provided over the support. The display portion has a top surface and a side surface in contact with at least one side of the top surface. The side surface has a second curved surface. The top surface includes a first display region. The side surface includes a second display region. The first display region and the second display region are continuously provided.

Abstract: An electronic device having a novel structure, specifically, an electronic device having a novel structure that can be changed into various appearances is provided. Specifically, after an active material layer is formed on one or both surfaces of a current collector, the active material layer in a bent region is partly removed. The removed region of the active material layer can be in a linear shape, a dot shape, or a matrix shape, for example. After the active material layer is formed on one or both surfaces of the current collector, laser processing for removing part of the active material layer in an irradiation region is performed using laser light or the like. On the region where the surface of the current collector is exposed, the active material layer is not provided, and this region is a region that does not function as a battery. Owing to this region, a secondary battery with a wide movable region can be achieved.

Abstract: Disclosed is a power storage unit which can safely operate over a wide temperature range. The power storage unit in a power storage device; a heater for heating the power storage device; a temperature sensor for sensing the to of the power storage device; and a control circuit configured to in charge of the power storage device when its temperature is lower than a first temperature or higher than a second temperature. The first temperature is exemplified by a temperature which allows the formation of a dendrite over a negative electrode of the power storage device, whereas the second temperature is exemplified by a temperature which causes decomposition of a passivating film formed over a surface of a negative electrode active material.

Abstract: A novel electronic device is provided. Alternatively an electronic device of a novel embodiment is provided. An electronic device includes a ring portion and a display portion. The display portion is flexible. The display portion has a top surface and a first side surface in contact with at least one side of the top surface. The first side surface has a curved surface. The top surface includes a first display region. The first side surface includes a second display region. The first display region and the second display region are continuously provided. The electronic device is mounted such that the ring portion is in contact with a user's finger.

Abstract: Provided is an electronic device with high portability and/or high browsability. The electronic device includes first and second support bodies, a first hinge, and a flexible display panel. The first hinge has a first rotation axis and connects the first and second support bodies to each other, and the first and second support bodies are capable of relatively rotating on the first rotation axis. The display panel includes at least first and second portions supported by the first and second support bodies, respectively; the first rotation axis and a first plane including the display surface overlapping with the first portion or a second plane including the display surface overlapping with the second portion are parallel to each other; and each of a distance between the first rotation axis and the first plane or the second plane is greater than zero.

Abstract: To provide a light-emitting device capable of being used in a wide temperature range. To provide a light-emitting device capable of being used in a low-temperature environment and a high-temperature environment. The light-emitting device includes a light-emitting panel, a secondary battery, a circuit, and a sealing structure. The light-emitting panel includes a light-emitting element. The light-emitting element can emit light with power supplied from the secondary battery. The circuit includes an antenna and can charge the secondary battery wirelessly. The light-emitting panel, the secondary battery, and the circuit are provided in the sealing structure. The sealing structure includes a portion through which light emitted from the light-emitting element passes.