To provide a secondary battery in which a side reaction does not easily occur at an interface between a positive electrode active material and a solid electrolyte, an interface between the positive electrode active material and a positive electrode current collector, or the like even when charge and discharge are repeated. In one embodiment of the present invention, a buffer layer or a protective layer is provided on a current collector surface or between a current collector layer and an active material layer to prevent deterioration such as oxidation of the current collector. As the buffer layer or the protective layer, it is possible to use a titanium compound such as titanium oxide, titanium oxide in which nitrogen is substituted for part of oxygen, titanium nitride, titanium nitride in which oxygen is substituted for part of nitrogen, or titanium oxynitride (TiO.sub.xN.sub.y, where 0<x<2 and 0<y<1). Titanium nitride is particularly preferable because it has high conductivity and has a high capability of inhibiting oxidation.

The solid electrolyte material consists essentially of Li, Ti, M, and F. Here, M is at least one selected from the group consisting of Al and Y.

The present invention provides: an electrode mixture manufacturing method comprising the processes of introducing a first binder, an electrode active material, and a conductive material into an extruder, performing a first mixing of the first binder, the electrode active material, and the conductive material in the extruder, additionally introducing a second binder into the extruder and performing a second mixing, and yielding an electrode mixture resulting from the first mixing and the second mixing; an electrode mixture manufactured thereby; and an electrode manufacturing method using the electrode mixture.

An apparatus comprises a reaction chamber and at least one negative electrode reservoir configured to contain a negative electrode material. A heating system is configured to heat negative electrode material within the at least one negative electrode material reservoir and the reaction chamber and to heat positive electrode material in reaction chamber. An electrode material distribution system is configured to manage the transfer of fluid electrode material between the at least one negative electrode reservoir and the reaction chamber.

An apparatus comprises a reaction chamber and at least one negative electrode reservoir configured to contain a negative electrode material. A heating system is configured to heat negative electrode material within the at least one negative electrode material reservoir and the reaction chamber and to heat positive electrode material in reaction chamber. An electrode material distribution system is configured to manage the transfer of fluid electrode material between the at least one negative electrode reservoir and the reaction chamber.

The adhesion between metal foil serving as a current collector and a negative electrode active material is increased to enable long-term reliability. An electrode active material layer (including a negative electrode active material or a positive electrode active material) is formed over a base, a metal film is formed over the electrode active material layer by sputtering, and then the base and the electrode active material layer are separated at the interface therebetween; thus, an electrode is formed. The electrode active material particles in contact with the metal film are bonded by being covered with the metal film formed by the sputtering. The electrode active material is used for at least one of a pair of electrodes (a negative electrode or a positive electrode) in a lithium-ion secondary battery.

The adhesion between metal foil serving as a current collector and a negative electrode active material is increased to enable long-term reliability. An electrode active material layer (including a negative electrode active material or a positive electrode active material) is formed over a base, a metal film is formed over the electrode active material layer by sputtering, and then the base and the electrode active material layer are separated at the interface therebetween; thus, an electrode is formed. The electrode active material particles in contact with the metal film are bonded by being covered with the metal film formed by the sputtering. The electrode active material is used for at least one of a pair of electrodes (a negative electrode or a positive electrode) in a lithium-ion secondary battery.

According to one embodiment, an electrospinning apparatus deposits a fiber on an electrode. The apparatus includes a transport section and a fiber deposition section. The transport section transports electrodes. The fiber deposition section deposits the fiber on first and second surfaces of the electrodes. The electrodes include coated and uncoated portions. The transport section transports the electrodes in a third direction in the fiber deposition section. The electrodes include first and second electrodes. The first electrode is positioned at one end in the second direction and transported so that the uncoated portion of the first electrode protrudes toward the one end side. The second electrode is positioned at other end in the second direction and transported so that the uncoated portion of the second electrode protrudes toward the other end side.

In a secondary battery including a large-sized electrode group including stacked positive and negative electrode plates, an electrode plate in which failures such as the separation and cracking of an active material layer and the abrasion and cracking of a current collector are unlikely to occur is provided. An electrode plate 21 includes a coated region CR where active material layers 21a are formed and an uncoated region NC where no active material layer is formed and has a configuration in which a boundary section between the coated region and the uncoated region is provided with a first buffer region C2 having a non-linear irregular shape in plan view.

In a secondary battery including a large-sized electrode group including stacked positive and negative electrode plates, an electrode plate in which failures such as the separation and cracking of an active material layer and the abrasion and cracking of a current collector are unlikely to occur is provided. An electrode plate 21 includes a coated region CR where active material layers 21a are formed and an uncoated region NC where no active material layer is formed and has a configuration in which a boundary section between the coated region and the uncoated region is provided with a first buffer region C2 having a non-linear irregular shape in plan view.