Abstract:
A lithium-ion secondary battery with no negative electrode active material is provided. One embodiment of the present invention is a lithium-ion secondary battery including a positive electrode, a negative electrode, an electrolyte solution, and a separator between the positive electrode and the negative electrode. The negative electrode includes a negative electrode current collector which includes a region in direct contact with at least one of the electrolyte solution and the separator. The electrolyte solution contains fluorine. The negative electrode current collector has a function of making a deposit containing lithium to be deposited on a surface in charging. Furthermore, a spacer may be provided between the separator and the negative electrode. The electrolyte solution may contain an organic compound containing fluorine. Supply of fluorine from the electrolyte solution to lithium deposited on the surface of the negative electrode can suppress deposition of lithium dendrites (whiskers) in further deposition.
Abstract:
A lithium ion secondary battery includes a positive electrode including a positive electrode active material layer containing lithium iron phosphate, a negative electrode including a negative electrode active material layer containing graphite, and an electrolyte including a lithium salt and a solvent including ethylene carbonate and diethyl carbonate between the positive electrode and the negative electrode. When the battery temperature of the lithium ion secondary battery or the temperature of an environment in which the lithium ion secondary battery is used is T and given temperatures are T1 and T2 (T1
Abstract:
A lithium ion secondary battery includes a positive electrode including a positive electrode active material layer containing lithium iron phosphate, a negative electrode including a negative electrode active material layer containing graphite, and an electrolyte including a lithium salt and a solvent including ethylene carbonate and diethyl carbonate between the positive electrode and the negative electrode. When the battery temperature of the lithium ion secondary battery or the temperature of an environment in which the lithium ion secondary battery is used is T and given temperatures are T1 and T2 (T1
Abstract:
A semiconductor device in which a circuit and a battery are efficiently stored is provided. In the semiconductor device, a first transistor, a second transistor, and a secondary battery are provided over one substrate. A channel region of the second transistor includes an oxide semiconductor. The secondary battery includes a solid electrolyte, and can be fabricated by a semiconductor manufacturing process. The substrate may be a semiconductor substrate or a flexible substrate. The secondary battery has a function of being wirelessly charged.
Abstract:
An object is to reduce variation in shape of crystals that are to be formed. Solutions containing respective raw materials are made in an environment where an oxygen concentration is lower than that in air, the solutions containing the respective raw materials are mixed in an environment where an oxygen concentration is lower than that in air to form a mixture solution, and with use of the mixture solution, a composite oxide is formed by a hydrothermal method.
Abstract:
To provide a highly reliable power storage device, to improve the security of a power storage device, and to suppress deterioration of a power storage device, a power storage device includes, inside an exterior material, a positive electrode, a negative electrode facing the positive electrode, an electrolyte solution between the positive electrode and the negative electrode, and an adsorbent. A separation body which is impermeable to the electrolyte solution and permeable to a gas is provided between the electrolyte solution and the adsorbent.
Abstract:
To inhibit degradation of charge and discharge cycle characteristics of a secondary battery. To suppress generation of defects due to expansion and contraction of an active material in a negative electrode. To inhibit deterioration of an electrode due to changes in its form. An electrode member including a current collector, an active material, and a porous body is used. The porous body is in contact with one surface of the current collector and includes a plurality of spaces. The active material is located in the space in the porous body. The space has a larger size than the active material.
Abstract:
Disclosed is a power storage unit which can safely operate over a wide temperature range. The power storage unit includes: a power storage device; a heater for heating the power storage device; a temperature sensor for sensing the temperature of the power storage device; and a control circuit configured to inhibit 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 thin energy storage device having high capacity is obtained. An energy storage device having high output is obtained. A current collector and an active material layer are formed in the same manufacturing step. The number of manufacturing steps of an energy storage device is reduced. The manufacturing cost of an energy storage device is suppressed. One embodiment of the present invention relates to an electric double layer capacitor which includes a pair of electrodes including a porous metal material, and an electrolyte provided between the pair of electrodes; or a lithium ion capacitor which includes a positive electrode that is a porous metal body functioning as 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 provided between the positive electrode and the negative electrode.
Abstract:
Disclosed is a power storage element including a positive electrode current collector layer and a negative electrode current collector layer which are arranged on the same plane. The power storage element further includes a positive electrode active material layer over the positive electrode current collector layer and a negative electrode active material layer over the negative electrode current collector layer. An electrolyte layer in contact with at least the positive electrode active material layer and the negative electrode active material layer is provided. The electrolyte layer may be a solid electrolyte layer.