Abstract:
An object is to inhibit a decrease in the capacity of a power storage device or to compensate the capacity, by adjusting or rectifying an imbalance between a positive electrode and a negative electrode, which is caused by decomposition of an electrolyte solution at the negative electrode. Provided is a charging method of a power storage device including a positive electrode using an active material that exhibits two-phase reaction, a negative electrode, and an electrolyte solution. The method includes the steps of, after constant current charging, performing constant voltage charging with a voltage that does not cause decomposition of the electrolyte solution until a charging current becomes lower than or equal to a lower current value limit; and after the constant voltage charging, performing additional charging with a voltage that causes decomposition of the electrolyte solution until a resistance of the power storage device reaches a predetermined resistance.
Abstract:
A lithium-ion secondary battery having stable charge characteristics and lifetime characteristics is manufactured. Before the secondary battery is completed, a positive electrode is subjected to an electrochemical reaction in a large amount of electrolyte solution in advance, so that the positive electrode can have stability. The use of the positive electrode enables the secondary battery to be highly reliable. If a negative electrode is also subjected to an electrochemical reaction in a large amount of electrolyte solution in advance, the secondary battery can be more highly reliable.
Abstract:
A flexible power storage device or a power storage device of which the capacity and cycle characteristics do not easily deteriorate even when the power storage device is curved is provided. An electrode in which an active material layer, a current collector, and a friction layer are stacked in this order is provided. Furthermore, a power storage device that includes the electrode as at least one of a positive electrode and a negative electrode is provided.
Abstract:
To provide a lithium-ion storage battery or electronic device that is flexible and highly safe. One embodiment of the present invention is a flexible storage battery including a positive electrode, a negative electrode, a separator between the positive electrode and the negative electrode, an exterior body that surrounds the positive electrode, the negative electrode, and the separator, and a wiring provided along the exterior body. At least part of the wiring is more easily breakable by deformation than the exterior body. The wiring is more vulnerable to deformation than the exterior body and thus damaged earlier than the exterior body. Damage to the wiring is detected and an alert is sent to a user; thus, the use of the storage battery can be stopped before the exterior body is damaged.
Abstract:
To provide a fabricating method and a fabricating apparatus for a lithium-ion secondary battery having stable charge characteristics and lifetime characteristics. A positive electrode is subjected to an electrochemical reaction in a large amount of electrolytic solution in advance before a secondary battery is completed. In this manner, the positive electrode can have stability. The use of the positive electrode enables fabrication of a highly reliable secondary battery. Similarly, a negative electrode is subjected to an electrochemical reaction in a large amount of electrolytic solution in advance. The use of the negative electrode enables fabrication of a highly reliable secondary battery.
Abstract:
To provide a carbon-based negative electrode material which can be used with an electrolyte containing PC as a main ingredient, a carbon-based negative electrode material having a graphene layer structure is crystalline and has pores. That is, the crystal structure of the carbon-based negative electrode material is distorted more significantly than that of graphite. Accordingly, the carbon-based negative electrode material has a larger interlayer distance between graphenes than graphite. It has been shown that such a negative electrode material can be used for a secondary battery which contains an electrolyte containing PC as a main ingredient.
Abstract:
A decrease in the capacity of a power storage device is inhibited by adjusting or reducing imbalance in the amount of inserted and extracted carrier ions between positive and negative electrodes, which is caused by decomposition of an electrolyte solution of the negative electrode. Further, the capacity of the power storage device can be restored. Furthermore, impurities in the electrolyte solution can be decomposed with the use of the third electrode. A power storage device including positive and negative electrodes, an electrolyte, and a third electrode is provided. The third electrode has an adequate electrostatic capacitance. The third electrode can include a material with a large surface area. In addition, a method for charging the power storage device including the steps of performing charging by applying a current between the positive and negative electrodes, and performing additional applying a current between the third electrode and the negative electrode is provided.
Abstract:
A power storage device with high output is provided, in which the specific surface area is increased while keeping the easy-to-handle particle size of its active material. The power storage device includes a positive electrode including a positive electrode current collector and a positive electrode active material layer, a negative electrode including a negative electrode current collector and a negative electrode active material layer, and an electrolyte. The negative electrode active material layer includes a negative electrode active material which is a particle in which a plurality of slices of graphite is overlapped with each other with a gap therebetween. It is preferable that the grain diameter of the particle be 1 μm to 50 μm. Further, it is preferable that the electrolyte be in contact with the gap between the slices of graphite.
Abstract:
An information processing system including a first information processing device and a second information processing device is provided. The first information processing device generates a first processing result including a first translation and a second translation in accordance with a first prompt and transmits the first processing result. The first information processing device generates a second processing result including a third translation and a fourth translation in accordance with a second prompt and transmits the second processing result. The second information processing device is configured to receive a document, metadata, a summary, a first processing result, and a second processing result. The second information processing device is configured to cut a character string with a predetermined length from the beginning of the document.
Abstract:
Provided is an electronic device that can be operated without contact. The electronic device includes a display portion, a processing portion, and a memory portion. The display portion includes a display apparatus including a light-emitting device and a light-receiving device. The display portion has a function of displaying an image using the light-emitting device and a function of capturing an image using the light-receiving device. The memory portion has a machine learning model using a neural network. The processing portion has a function of inferring position data of an object not in contact with the electronic device using the machine learning model from image capturing data captured by the display portion.