Assembled battery and manufacturing method of assembled battery

Abstract

In an assembled battery 1 disclosed herein, each of adjacent single cells 10 is electrically connected by a busbar 30. The busbar 30 of the assembled battery 1 includes a plate-shaped base portion 32 which extends along an arrangement direction X, and a joining projection 36 extending along electrode terminals 12 and 14 and a locking biasing portion 38 which locks the electrode terminals 12 and 14 and the busbar 30 to each other and which biases the electrode terminals 12 and 14 toward the joining projection 36 are formed at both ends of the base portion 32. Furthermore, in the assembled battery 1 disclosed herein, the electrode terminals 12 and 14 and the joining projection 36 come into surface contact with each other and tip portions 12a and 14a of the electrode terminals 12 and 14 and a tip portion 36a of the joining projection 36 are welded to each other. Accordingly, welding between the electrode terminals 12 and 14 and the busbar 30 can be performed in an appropriate manner.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]The present application claims priority on the basis of Japanese Patent Application No. 2018-58566 filed in Japan on Mar. 26, 2018, the entire contents of which are incorporated herein by reference.BACKGROUND1. Technical Field[0002]The present disclosure to an assembled battery in which a plurality of single cells are electrically connected and to a method of manufacturing the assembled battery.2. Description of the Related Art[0003]Assembled batteries using a secondary battery such as a lithium-ion secondary battery or a nickel-hydrogen battery or a storage element such as a capacitor as a single cell and including a plurality of the single cells are growing in importance as vehicle-mounted power supplies and as power supplies for personal computers, mobile phones, and the like. In particular, assembled batteries using a lithium-ion secondary battery which is lightweight and which is capable of producing high energy density as a single c...

AI Technical Summary

Benefits of technology

The patent aims to solve issues in welding busbars and electrode terminals in batteries. The invention provides a technique that can appropriately perform joint welding and prevent damage to cells or poor welds. The method allows for the use of various welding means, including laser welding and ultrasonic welding, which can ensure proper positioning and surface contact between the electrode terminal and busbar for better weld quality.

Problems solved by technology

However, with the assembled battery 100 structured as described above, there is a risk that the welding of the busbar 130 and the electrode terminals 112 to each other may not be appropriately performed and damage to the single cell 110, a poor weld, or the like may occur.

As a result of the studies, the fact that a state of welding cannot be checked from the outside of the busbar in conventional assembled batteries was considered to be one of the causes of occurrences of the problems described above.

As a result, it is difficult to appropriately adjust the irradiation condition of the laser beam L and a likelihood of an occurrence of damage to the single cell 110 due to the laser beam L being excessively strong or a connection failure due to the laser beam L being excessively weak increases.

In addition, the present inventors considered that, with conventional techniques, it is difficult to bring welded objects into contact with each other in an appropriate manner.

Furthermore, with conventional techniques, even when a gap has been created between the welded objects, the creation of the gap cannot be confirmed.

However, since a laminated film is less rigid than a metallic case, there is a problem in that it is difficult to position single cells when arranging the single cells.

Furthermore, since a laminated film is less heat-resistant than a metallic case, there is another problem in that, when welding the electrode terminal and the busbar to each other using a laser beam, a single cell may become readily damaged when the outer package is irradiated by the laser beam.

As described earlier, with conventional techniques, various problems including damage to a single cell and a poor weld may occur when performing laser welding.

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