A lead member for a secondary battery includes a conductor, and a covering material. The conductor has an upper surface and a lower surface that extend in a length direction and a width direction and are opposite to each other, and a first side surface and a second side surface that extend in the length direction and a thickness direction, connect the upper surface to the lower surface, and are opposite to each other. The covering material is formed by sticking a plurality of insulating films together to surround the upper surface, the first side surface, the lower surface, and the second side surface. Each of the plurality of insulating films includes an inner layer and an outer layer, in an order from a side closer to the conductor. The lead member includes a first insulator and a second insulator on the first side surface and the second side surface of the conductor respectively, in an area surrounded by the covering material of the conductor. The first insulator and the second insulator have a lower melting point than the inner layer. The first insulator and the second insulator are placed to be separated from each other.

A lead member for a secondary battery includes a conductor, and a covering material. The conductor has an upper surface and a lower surface that extend in a length direction and a width direction and are opposite to each other, and a first side surface and a second side surface that extend in the length direction and a thickness direction, connect the upper surface to the lower surface, and are opposite to each other. The covering material is formed by sticking a plurality of insulating films together to surround the upper surface, the first side surface, the lower surface, and the second side surface. Each of the plurality of insulating films includes an inner layer and an outer layer, in an order from a side closer to the conductor. The lead member includes a first insulator and a second insulator on the first side surface and the second side surface of the conductor respectively, in an area surrounded by the covering material of the conductor. The first insulator and the second insulator have a lower melting point than the inner layer. The first insulator and the second insulator are placed to be separated from each other.

Provided is a secondary battery, including: an electrode assembly, a packing bag, an electrode lead and an insulation part; the electrode assembly is housed in the packing bag having a sealing part on edge, and the electrode lead is connected to the electrode assembly and passes through the sealing part. The sealing part includes a main body area, a first step area and a first transition area which are located on same side of the electrode lead along width direction, and the main body area, first transition area and first step area are successively arranged along direction approaching the electrode lead; the insulation part is wrapped around the electrode lead, and has a first portion which is located on a side of the electrode lead close to the main body area along width direction and covered by the first step area on both sides in thickness direction.

The present disclosure provides a battery core assembly, a battery, a battery pack, and a vehicle. The battery core assembly includes an encapsulation film and an electrode core assembly encapsulated in the encapsulation film. The electrode core assembly includes an electrode core assembly body and two electrode lead-out members of opposite polarities electrically connected to the electrode core assembly body. The electrode core assembly body includes at least two electrode cores connected in parallel. Each of the electrode cores includes an electrode core body and two tabs of opposite polarities that are electrically connected to the electrode core body. The electrode core assembly body further includes a tab support. The two electrode lead-out members are respectively electrically connected to one of the tab supports located two sides of the electrode core assembly body in a first direction.

A battery core assembly includes an encapsulation film and multiple electrode core assemblies disposed in the encapsulation film. The electrode core assemblies are connected to form an electrode core string, and each of the electrode core assemblies includes at least one electrode core. A spacer is disposed between two adjacent electrode core assemblies, the first spacer divides an accommodating space inside the encapsulation film into multiple accommodating cavities, cavity walls of the accommodating cavities includes the first spacer and the encapsulation film connected to the first spacer, and the electrode core assemblies are respectively accommodated in the accommodating cavities. The first spacer includes at least one first liquid reservoir, and the at least one first liquid reservoir communicates with one of accommodating cavities on both sides of the first spacer.

An electrical contact assembly includes a first component and a second component having a stem with a first end and a second end opposite the first end. A flange extends from the first end and defines an electrical contact surface area. The second end is permanently joined to the first component at a mating surface. The mating surface defines a first surface area at the second end and the electrical surface area is equal to or greater than the first surface area.

An electrical contact assembly includes a first component and a second component having a stem with a first end and a second end opposite the first end. A flange extends from the first end and defines an electrical contact surface area. The second end is permanently joined to the first component at a mating surface. The mating surface defines a first surface area at the second end and the electrical surface area is equal to or greater than the first surface area.

A secondary battery includes outer package members each having flexibility and a battery device. The outer package members each include a thermal-fusion-bonding layer. The battery device is contained in an inside of the outer package members, and includes a positive electrode, a negative electrode, and an electrolytic solution. The outer package members are sealed at a thermal-fusion-bonding part. The thermal-fusion-bonding part is formed by the thermal-fusion-bonding layers being thermal-fusion-bonded to each other. The thermal-fusion-bonding layer includes polypropylene. The electrolytic solution includes a solvent and an electrolyte salt. The solvent includes a chain carboxylic acid ester. The thermal-fusion-bonding layer has a thickness of greater than or equal to 25 μm and less than or equal to 60 μm. The thermal-fusion-bonding part has a length of greater than or equal to 160 mm and less than or equal to 650 mm. The thermal-fusion-bonding part has a width of greater than or equal to 3 mm and less than or equal to 6 mm. A dimensional ratio defined by the thickness of the thermal-fusion-bonding layer, the length of the thermal-fusion-bonding part, and the width of the thermal-fusion-bonding part satisfies a condition represented by Expression (1). A drawn amount of the outer package members is less than or equal to 7.8 mm. A content of the chain carboxylic acid ester in the solvent is greater than or equal to 30 vol % and less than or equal to 60 vol %.

0.16≤(T×L)/W≤0.32   (1)

Where:
(T×L)/W is the dimensional ratio;
T is the thickness (cm) of the thermal-fusion-bonding layer;
L is the length (cm) of the thermal-fusion-bonding part; and
W is the width (cm) of the thermal-fusion-bonding part.

A battery cell electrode alignment inspection method for inspecting an alignment state of a jelly roll configured of negative and positive electrode plates and a separator of a battery cell includes: obtaining electrode vision image data by capturing vision images of individual negative and positive electrode plates configuring the jelly roll by a vision camera; obtaining dimensional data of the individual negative and positive electrode plates; storing the obtained dimensional data of the individual negative and positive electrode plates; marking a cell barcode for identification of the jelly roll; scanning the cell barcode to receive dimensional data of individual negative and positive electrode plates; X-ray-capturing the jelly roll to obtain X-ray image data of the individual negative and positive electrode plates; and substituting the dimensional data of the individual negative and positive electrode plates to the obtained X-ray images of the individual negative and positive electrode plates.

A manufacturing method of a welded structure in which metal members are welded to each other includes bringing the metal members into contact with each other so as to form a space surrounded by the metal members, a pressure reducing port is formed between the metal members or in at least one metal member of the metal members, the manufacturing method of the welded structure further includes performing a suction operation on the space through the pressure reducing port to depressurize the space so as to bring the first portion of the metal member into contact with the second portion of the metal member, or to make a distance between the first portion and the second portion smaller than that when the space is not depressurized; and welding the first portion and the second portion to each other in a state where the space is depressurized.