Battery

Abstract

A battery has current collectors and terminals in stable contacing status that represses the poor contact caused by applying impact such as falling, and fine quality and outer casing sealing performance. At a central portion of a lid (3) of a battery, a negative terminal (4), which has a T-shaped section view, is provided so as to be surrounded by a gasket (5) and pierce the lid (3). An insulator (6) is provided at the inner face side of the lid (3). A plate-like current collector (7) is placed in a recess (6a) of the insulator (6). Notches (72a) are provided at two positions of an insertion hole which is provided at one end portion side of the current collector (7). By inserting the negative terminal (4) into the insertion hole and crimping an end portion of a leg portion (42) of the negative terminal (4), the negative terminal (4) is fixed to the current collector (7) with a deforming part of the end portion eating into the notches (72a) and being locked.

Description

technical field [0001] The present invention relates to a battery formed by accommodating battery elements in a case and covering an opening of the case with a cover portion. Background technique [0002] In recent years, with the miniaturization, weight reduction and diversification of portable electronic devices such as video cameras, on-board computers, and mobile phones, there is a strong demand for the development of small and lightweight power supplies that have high energy density, storage stability, and high reliability. , A secondary battery that can be repeatedly charged and discharged for a long time. [0003] Secondary batteries satisfying these requirements include nonaqueous electrolyte secondary batteries containing a nonaqueous electrolyte. [0004] A lithium ion secondary battery is mentioned as a representative example of a nonaqueous electrolyte secondary battery. The lithium-ion secondary battery has a negative electrode composed of an active material c...

AI Technical Summary

Problems solved by technology

Therefore, there is a problem that when the lithium ion secondary battery is dropped or the like is impacted, the fastening portion 54c rotates, and the contact state between the negative electrode terminal 54 and the current collector 57 tends to deteriorate, and the connection resistance increases.

However, there is a problem that the process becomes complicated due to the addition of a welding process, and a part of the insulator 56 is melted due to the heat energy of welding, and the sealing performance of the cover portion 53 formed by the insulator 56 deteriorates, and the non-aqueous electrolyte may leak out.

[0017] In the battery disclosed in the above-mentioned Utility Application Publication No. 5-31108, the rotation of the rivet is suppressed, but when the battery is dropped or subjected to an impact, the fastening part of the rivet and the contact part of the gasket may be deformed, resulting in poor contact.

[0018] In the battery disclosed in Japanese Patent Laid-Open No. 2003-45404, protrusions are continuously provided in a circular shape around the periphery of the electrode lead-out plate. Therefore, there is a problem that when fastening the outer ends of the electrode lead-out pins to the electrode lead-out plate, It is difficult for the electrode lead-out pins to go deep into the electrode lead-out plate side. In addition, the electrode lead-out pins are easy to rotate relative to the ring-shaped protrusion. When an impact is applied to the battery, poor contact may occur.

[0019] In the battery disclosed in Publication No. 7-27051, the feet of the rivet terminals are oblong in plan view and have a long circumference. In addition, the distance from the central axis varies depending on the position of the end edges of the feet. Therefore, it is difficult to tighten them evenly. solid, there is a possibility of poor contact between the foot and the lead member

[0020] In the battery disclosed in JP-A-6-231740, similarly to the above, the process becomes complicated due to the addition of a welding process, and a part of the synthetic resin cover part may be melted due to the heat energy of the welding, and the cover part and the gasket are separated. Deterioration of contact performance, deterioration of sealing performance against non-aqueous electrolytes, etc.

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