The subject matter relates to a welding device as well as a welding method for producing a material bond connection between a conductor (10) and a connecting part (8), with at least one ultrasonic welding tool (4), wherein at least part of a contact surface (18) of the connecting part (8) contacts at least part of a contact surface (16) of the ultrasonic welding tool (4).

A laser welding method is usable to weld a material containing copper as a main component. The laser welding method includes heating the material by irradiation with a first laser light and welding the material by irradiation of a portion, which has been irradiated with the first laser light, of the material with a second laser light with which an energy absorption rate of the copper contained in the material increases by an increase in a temperature of the material. A wavelength of the first laser light is 400 nm to 470 nm.

The present disclosure provides a battery protection circuit board and a preparation method thereof. The battery protection circuit board includes a first battery protection board and a second battery protection board, a hardness of the first battery protection board being greater than a hardness of the second battery protection board. The soldering method includes: preparing a first to-be-soldered region of the first battery protection board and preparing a second to-be-soldered region of the second battery protection board; preparing a first copper paste in the first to-be-soldered region of the first battery protection board and preparing a second copper paste in the second to-be-soldered region of the second battery protection board; and bonding the first to-be-soldered region of the first battery protection board and the second to-be-soldered region of the second battery protection board by the first copper paste and the second copper paste.

To arrange an auxiliary member (2) having a greater absorption rate of laser light (LL) than a plurality of members (1) to be joined to each other so as to face a boundary exposed surface (12) of the plurality of members to be joined where a boundary (11) of the plurality of members to be joined is exposed, to melt the auxiliary member by applying laser light to the auxiliary member, to shift a boundary portion (13) in a state where laser light is easily absorbed by increasing a temperature of the boundary portion of the plurality of members to be joined by a melted portion (23) of the auxiliary member, and to weld a plurality of members to be joined by applying laser light to the boundary portion and melting the boundary portion.

According to the present disclosure, it is possible to inhibit the electrically conductive foreign substance from falling off and being peeled off from the electrode plate that has been already manufactured, so as to contribute in improving the safety property of the secondary battery. The manufacturing method of the electrode plate herein disclosed includes a precursor preparing step for preparing an electrode precursor 20A including an active material provided area A1 in which an electrode active material layer 24 is provided on a surface of the electrode core 22 and including a core exposed area A2 in which the electrode active material layer 24 is not provided and the electrode core 22 is exposed, and an active material provided area cutting step for cutting the active material provided area A1 by a pulse laser, and a core exposed area cutting step for cutting the core exposed area A2 by the pulse laser. Then, in the case where the pulse width (ns) of the pulse laser is represented by X and the lap rate (%) is represented by Y for the core exposed area cutting step, a condition represented by Y≥−3log X+106 is satisfied. According to the manufacturing method of the electrode plate as described above, it is possible to inhibit the electrically conductive foreign substance from falling off and being peeled off from the electrode plate that has been already manufactured, and thus it is possible to contribute in improving the safety property of the secondary battery.

An ultrasonic joining horn disclosed herein can generate ultrasonic vibration in a predetermined vibration direction and includes a base portion, a stand portion that rises from an upper surface of the base portion, and a pressure contact portion formed of a plurality of protrusions that protrude from an upper surface of the stand portion. Each of the protrusions is formed into a pyramid shape or a truncated pyramid shape, the protrusions are arrayed, and when viewed from top, at least a portion of a peripheral edge of a portion in which the protrusions are arrayed has a zigzag shape. The zigzag portion is formed along at least one of the vibration direction and a perpendicular direction to the vibration direction. The upper surface of the base portion has an exposed surface on which the stand portion is not formed.

A mechanical vibration machining method or the like is suitable for allowing a probe to provide vibration to a horn with high efficiency. A horn portion is supported by a first support portion and a second support portion configured as a double-support structure. A first probe unit and a second probe unit are coupled to both ends of the horn portion. The first probe unit and the second probe unit vibrate the horn portion by means of vibration generated by a first generation unit and a second generation unit. The horn portion provides nodal points at which elongation and contraction alternately occur. For example, in a case in which the contact portion is arranged at the center of the horn portion, the second generation unit is oscillated with a phase that is the opposite of that of the first generation unit.

A method and associated device for joining a battery cell tab to a plurality of foils associated with a plurality of electrodes of a battery cell are described. This includes arranging the plurality of foils in a stack, and joining, via a first joining device, the plurality of foils, wherein the first joining device defines a joining region. A portion of the battery cell tab is arranged on the plurality of foils, and joined, via a second joining device, to the plurality of foils. The second joining device generates a weld joint that is encompassed within the joining region defined by the first joining device. In doing so, weld quality and strength of internal welds in a battery cell may be improved by reducing the occurrence of porosities and cracks in the foil/tab weld joints.

According to the present invention, there is provided a copper/ceramic bonded body including: a copper member made of copper or a copper alloy; and a ceramic member made of silicon-containing ceramics, the copper member and the ceramic member being bonded to each other, in which a maximum indentation hardness in a region is set to be in a range of 70 mgf/μm.sup.2 or more and 150 mgf/μm.sup.2 or less, the region being from 10 μm to 50 μm with reference to a bonded interface between the copper member and the ceramic member toward the copper member side.

According to an embodiment, there are provided a method for manufacturing a battery module for an electric vehicle and a battery module manufactured by the method. The method comprises preparing an electrode assembly, the electrode assembly including a plurality of electrode plates, a plurality of electrode tabs, and a separator, forming a plurality of electrode leads by friction-welding a copper piece and an aluminum piece, attaching a sealing film to each of the plurality of electrode leads, packing the electrode assembly in a pouch case, with the aluminum piece exposed to an outside of the pouch case, injecting an electrolyte into the pouch case, sealing the pouch case to form each of the plurality of battery cells, stacking the plurality of battery cells one over another, and connecting the aluminum pieces of the plurality of battery cells to each other via a sensing bus bar.