A cylindrical secondary battery configured to have a structure to which an adhesion unit, including an adhesive material, a conductive material, and a gas-generating material, is provided. The adhesion unit is configured to couple a cap assembly, which functions as a positive electrode terminal of the cylindrical secondary battery, and a positive electrode tab of a jelly-roll type electrode assembly to each other.

Disclosed are a pole plate, cell, and battery. The pole plate includes a current collector and a coating layer formed on at least one surface of the current collector. The coating layer includes a first coating zone and a second coating zone arranged on two sides of the first coating zone. A compaction density of the second coating zone is larger than that of the first coating zone.

A lithium ion battery according to the present invention comprises a positive electrode, a negative electrode, a positive electrode lead that is connected to the positive electrode, an insulation tape that covers the positive electrode lead, and an electrolyte solution. The insulation tape comprises a base material layer that is mainly composed of an organic material, and a filler layer that is provided on the base material layer; the filler layer contains an oxide compound of an alkaline earth metal; and the electrolyte solution contains fluorine.

This non-aqueous electrolyte secondary battery comprises an electrode body in which a first separator, a positive electrode plate, a second separator, and a negative electrode plate are layered and coiled for 10 or more turns. The electrode body includes: a flat section in which the outer peripheral surface is flat; and two curved surface sections which are disposed at both ends in a first direction of the flat section and in which the outer peripheral surface is curved. The non-aqueous electrolyte secondary battery includes: a winding-end tape that is adhered to the outermost peripheral surface of the electrode body; and a positive electrode protective tape that is adhered to a winding-start-side end section on the inner peripheral side of the positive electrode plate. The winding-end tape is disposed on one of the two curved surface sections.

This non-aqueous electrolyte secondary battery comprises an electrode body in which a first separator, a positive electrode plate, a second separator, and a negative electrode plate are layered and coiled for 10 or more turns. The electrode body includes: a flat section in which the outer peripheral surface is flat; and two curved surface sections which are disposed at both ends in a first direction of the flat section and in which the outer peripheral surface is curved. The non-aqueous electrolyte secondary battery includes: a winding-end tape that is adhered to the outermost peripheral surface of the electrode body; and a positive electrode protective tape that is adhered to a winding-start-side end section on the inner peripheral side of the positive electrode plate. The winding-end tape is disposed on one of the two curved surface sections.

With respect to a secondary battery of one embodiment of the present invention, at least one of a positive electrode core body and a negative electrode core body is configured such that the tensile elongation in the central part in the width direction is higher than the tensile elongation in both end parts in the width direction. With respect to a secondary battery of another embodiment of the present invention, at least one of a positive electrode core body and a negative electrode core body is configured such that the number of crystal grains per unit area in the central part in the width direction is smaller than the number of crystal grains per unit area in both end parts in the width direction.

With respect to a secondary battery of one embodiment of the present invention, at least one of a positive electrode core body and a negative electrode core body is configured such that the tensile elongation in the central part in the width direction is higher than the tensile elongation in both end parts in the width direction. With respect to a secondary battery of another embodiment of the present invention, at least one of a positive electrode core body and a negative electrode core body is configured such that the number of crystal grains per unit area in the central part in the width direction is smaller than the number of crystal grains per unit area in both end parts in the width direction.

A first electrode current collector is joined to a multilayer of a positive electrode core in a part including no positive electrode active material layer of the first electrode core, by ultrasonic welding in a joint area. The joint area, at which the multilayers of the first electrode core where the first electrode cores are stacked is joined to the first electrode current collector by ultrasonic welding, includes a plurality of core recesses. A core projection is formed between each adjacent pair of the plurality of core recesses of the multilayer of the first electrode core with the first electrode core flexed in a convex shape. A gap in an arc shape is formed between the adjacent pair of the layers of the first electrode core forming the core projection. The gap has a length decreasing from an apex to a bottom of the core projection.

A first electrode current collector is joined to a multilayer of a positive electrode core in a part including no positive electrode active material layer of the first electrode core, by ultrasonic welding in a joint area. The joint area, at which the multilayers of the first electrode core where the first electrode cores are stacked is joined to the first electrode current collector by ultrasonic welding, includes a plurality of core recesses. A core projection is formed between each adjacent pair of the plurality of core recesses of the multilayer of the first electrode core with the first electrode core flexed in a convex shape. A gap in an arc shape is formed between the adjacent pair of the layers of the first electrode core forming the core projection. The gap has a length decreasing from an apex to a bottom of the core projection.

Provided is a secondary battery including an electrode assembly and an outer case configured to house the electrode assembly. The secondary battery includes a terminal member provided on the outer case with an insulating material interposed therebetween and connected to a tab of the electrode assembly. The outer case is provided with a cavity through which the tab passes, the terminal member is bonded onto a surface of the outer case with the insulating material interposed therebetween, the surface being positioned around the cavity, and a part of a width dimension of a bonding region provided to surround the cavity for the bonding is reduced.