Sanyo Electric Co., Ltd.

Takenori Kimura

Toshiyuki Nohma

Yasuhiro Yamauchi

Takayuki Hattori

Taiki Kamifuji

Kousuke Yamamoto

Yoshinori Yokoyama

The positive electrode substrate exposed portions or the negative electrode substrate exposed portions, or both, of an electrode assembly is split into two groups, and therebetween is disposed an intermediate member made of a resin material and holding one or more connecting conductive members. Collector members for the substrate exposed portions split into two groups is electrically joined by a resistance welding method to the substrate exposed portions split into two groups, together with the connecting conductive member(s) of the intermediate member. The resin material portion of the intermediate member protrudes, in the extension direction of the substrate exposed portions split into two groups, beyond the ends of the substrate exposed portions split into two groups and the ends of the collector member to a prismatic outer can. This structure enables enhanced resistance between the substrate exposed portions and the collector member and curbs variation in the welding strength.

Prismatic sealed secondary battery

A prismatic secondary battery is provided with a negative/positive electrode collector (), which are disposed on either one of a wound negative/positive electrode substrate exposed portion (), and a negative/positive electrode collector receiving member () which is disposed on another surface. At least one of the negative/positive electrode collector has a recess portion () formed in part on a surface on the side not facing the negative/positive electrode substrate exposed portions so as to be thinner than the thickness of the other portion. Resistance welding is carried out in this recessed part, thereby a large welding nugget is formed between the negative/positive electrode exposed portion and the negative/positive electrode collector.

Prismatic secondary battery

A prismatic sealed secondary cell that is excellent in current collection efficiency and current collection stability, and capable of high output discharge. In the prismatic sealed secondary cell a laminate-type or a wound laminate-type flat electrode assembly is housed in a prismatic cell case, a pair of current collector plates are disposed on a flat portion of the outermost surface of the core exposed portion of the first electrode plate constituting the flat electrode assembly so that the pair of current collector plates sandwich the flat portion in the thickness direction, and a columnar connection conductive member is interposed between two-divided core exposed portion laminates in the flat portion sandwiched between the pair of current collector plates, and the pair of current collector plates, the columnar connection conductive member and the two-divided core exposed portion laminates are welded to each other.

Prismatic sealed secondary cell and method of manufacturing the same

In a sealed battery, a metal current carrying blockA having a protrusionon each of the two opposing faces is placed between positive or negative electrode substrate exposed portions that are divided into two so as to bring the protrusionon each of the two opposing faces into contact with the positive or negative electrode substrate exposed portions that are stacked, a pair of electrodesandfor resistance welding are brought into contact with positive electrode collector membersor negative electrode collector members that are each placed on the outermost surfaces of the positive electrode substrate exposed portionsor negative electrode substrate exposed portions, and resistance welding is performed with pressure applied between the pair of electrodesandfor resistance welding.

Current carrying block for resistance welding, and method for manufacturing sealed battery and sealed battery each using the current carrying block

In a prismatic sealed secondary battery according to an embodiment of the present invention, at least one of positive electrode substrate exposed portions and negative electrode substrate exposed portions of an electrode assembly is split into two groups, and therebetween are disposed intermediate members that are made of a resin material and hold one or more connecting conductive members. The two split substrate exposed portions are electrically connected to collector members and to at least one of the connecting conductive members by resistance-welding. Voids are formed in resin material portions of the intermediate members that are located around the resistance-welded portions of the connecting conductive members. Therefore, lowered resistance between the substrate exposed portions and the collector members and stabilized quality of the welds are realized and the manufacturing yield of the prismatic sealed secondary battery is improved.

Growing community of inventors

Naruto, Japan

Takenori Kimura