Patent application number | Description | Published |
20130067726 | LITHIUM SECONDARY BATTERY AND MANUFACTURING METHOD THEREOF - An object is to improve the cycle performance by improving the reactivity between lithium and a negative electrode active material in the case where an alloy-based material such as silicon is used as the negative electrode active material. A method of manufacturing a lithium secondary battery including a positive electrode including a positive electrode active material into/from which lithium can be inserted/extracted, a negative electrode including a negative electrode active material into/from which lithium can be inserted/extracted, and an electrolyte solution is provided. The method includes the steps of electrochemically inserting lithium into the negative electrode with use of a counter electrode before the lithium secondary battery is assembled, electrochemically extracting part of the lithium inserted into the negative electrode after the insertion, and assembling the lithium secondary after the extraction. | 03-21-2013 |
20130323585 | NEGATIVE ELECTRODE FOR POWER STORAGE DEVICE AND POWER STORAGE DEVICE - A decomposition reaction of an electrolyte solution and the like caused as a side reaction of charge and discharge is minimized in repeated charge and discharge of a lithium ion battery or a lithium ion capacitor, and thus the lithium ion battery or the lithium ion capacitor can have long-term cycle performance. A negative electrode for a power storage device includes a negative electrode current collector and a negative electrode active material layer which includes a plurality of particles of a negative electrode active material. Each of the particles of the negative electrode active material has an inorganic compound film containing a first inorganic compound on part of its surface. The negative electrode active material layer has a film in contact with an exposed part of the negative electrode active material and part of the inorganic compound film. The film contains an organic compound and a second inorganic compound. | 12-05-2013 |
20140099554 | MATERIAL FOR ELECTRODE OF POWER STORAGE DEVICE, POWER STORAGE DEVICE, AND ELECTRICAL APPLIANCE - To improve the reliability of a power storage device. A granular active material including carbon is used, and a net-like structure is formed on part of a surface of the granular active material. In the net-like structure, a carbon atom included in the granular active material is bonded to a silicon atom or a metal atom through an oxygen atom. Formation of the net-like structure suppresses reductive decomposition of an electrolyte solution, leading to a reduction in irreversible capacity. A power storage device using the above active material has high cycle performance and high reliability. | 04-10-2014 |
20140127566 | POWER STORAGE DEVICE ELECTRODE, METHOD FOR FORMING THE SAME, POWER STORAGE DEVICE, AND ELECTRICAL DEVICE - Irreversible capacity which causes a decrease in the charge and discharge capacity of a power storage device is reduced, and electrochemical decomposition of an electrolyte solution and the like on a surface of an electrode is inhibited. Further, the cycle characteristics of the power storage device is improved by reducing or inhibiting a decomposition reaction of the electrolyte solution and the like occurring as a side reaction in repeated charging and discharging of the power storage device. A power storage device electrode includes a current collector and an active material layer that is over the current collector and includes a binder and an active material. A coating film is provided on at least part of a surface of the active material. The coating film is spongy. | 05-08-2014 |
20150086860 | POWER STORAGE DEVICE - A power storage device with reduced initial irreversible capacity is provided. The power storage device includes a positive electrode, a negative electrode, and an electrolyte solution. The negative electrode includes a negative electrode active material and a water-soluble polymer. The electrolyte solution includes an ionic liquid. The ionic liquid includes a cation and a monovalent amide anion. | 03-26-2015 |
20150111107 | ELECTRODE AND SECONDARY BATTERY, AND MANUFACTURING METHOD THEREOF - To improve the adhesion between a current collector and an electrode active material so as to improve long-term reliability. An electrode is formed in the following manner: an electrode active material (a negative electrode active material or a positive electrode active material) is formed over a base, a conductive film is formed over the electrode active material by a sputtering method, the base and the electrode active material are separated at the interface therebetween, and the electrode active material is made in contact with a current collector. The conductive film has a surface with projections and depressions because the conductive film is formed on the electrode active material containing particles. Accordingly, moderate adhesion can be provided between the conductive film and the current collector, with which stress at the interface between the conductive film and the current collector can be reduced while conductivity is maintained. | 04-23-2015 |