Prismatic battery

Abstract

According to an embodiment of the invention, a prismatic battery includes an electrode group 10 contained in a prismatic metal outer can. The electrode group 10 has a positive electrode substrate exposed part 11 at one end and a negative electrode substrate exposed part 12 at the other end. The positive and negative electrode substrate exposed parts 11 and 12 are bundled and welded to positive and negative electrode current collectors 13 and 14, respectively. The positive electrode substrate exposed part 11 and positive electrode current collector 13 and the negative electrode substrate exposed part 12 and negative electrode current collector 14 are covered with an insulating frame 16 having an angled U-shaped cross section and an angled U-shaped outline. It is therefore possible to provide a prismatic battery of a simple structure including an electrode group whose ends are covered with an easily manufactured insulating cover in which the battery's volume energy density is maintained and an internal short circuit is prevented.

Description

technical field [0001] The present invention relates to prismatic batteries such as lithium ion batteries and alkaline batteries, and more particularly to an electrode group in which a positive electrode core exposed portion is formed at one end and a negative electrode core exposed portion is formed at the other end. A prismatic battery in a rectangular parallelepiped-shaped metal case. Background technique [0002] In recent years, energy density (Wh Lithium secondary batteries with high volumetric energy density (Wh / l) among them, prismatic batteries with high volumetric energy density (Wh / l) are attracting attention. [0003] Such a prismatic battery is generally produced in the following steps as described in Patent Document 1, for example. That is, at first positive electrode core (usually aluminum foil) is coated with positive electrode mixture containing positive electrode active material to make strip-shaped positive plate, and negative electrode core (usually cop...

AI Technical Summary

Problems solved by technology

[0009] However, since the mechanical strength of the insulating resin tape is small, when the flat electrode group 20 pasted with such an insulating resin tape is inserted into the metal outer casing 27, due to the opening of the flat electrode group 20 and the outer casing 27, Partial contact may cause damage due to breakage of the insulating resin tape, etc.

In addition, if the number of places where the insulating resin tape is pasted increases, the number of steps will also increase.

In this case, it is conceivable to cover the side portion of the positive electrode current collector 22 including the positive electrode core exposed portion 21a and the side portion of the negative electrode current collector 23 including the negative electrode core exposed portion 21b with a resin molded product. Resin molded products have a large shape, so not only will the cost of the part increase, but also it will be difficult to reduce the thickness, so the volumetric energy density will also decrease

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