Sanyo Electric Co., Ltd.

Yoshinobu Okumura

Hitoshi Tanaka

Ryuji Ohshita

Takashi Oda

Hideki Okajima

Yoshikumi Miyamoto

Yukichi Uesugi

Jun Okazaki

Toshiyuki Nohma

Yasuhiro Yamauchi

Naoya Nakanishi

Toshio Yanagida

Toshirou Yanagawa

Tadatoshi Fukuta

A nonaqueous secondary batteryof the invention has an active material compound layerdeposed over at least one face of a collectormade of metal foil and is equipped with a positive electrodehaving a portionin a part of which metal is exposed. The positive electrodetogether with the exposed-metal portionfaces a negative electrodethrough an interposed separator, and on that part of the exposed-metal portionthat faces the negative electrodethrough the interposed separatorthere is formed a protective layermade of a material whose electronic conductivity is lower than that of the metal and which moreover is non-insulative. With such nonaqueous secondary battery, should part of an electrode pierce the separator and contact with the other electrode, the battery will be gently discharged, thereby averting abnormal heat generation by the battery and additionally enabling the battery's abnormality to be sensed by the equipment via the fall in battery voltage. Thus, there is provided a nonaqueous secondary battery of excellent safety that can prevent abnormal heat generation due to a short circuit caused by burr, powder or the like piercing the separator.

Nonaqueous secondary battery

To provide a non-aqueous electrolyte secondary battery adapted to prevent an internal short circuit between an positive electrode and a negative electrode caused by the penetration of electrically conductive micro particles through a separator, which occurs when winding up electrodes, and manufacturing methods of an electrode used therein, whereby the non-aqueous electrolyte secondary battery having a coiled electrode assembly is formed through the multilayer winding of an positive electrodehaving a metallic collectorcoated with an positive electrode mixturecomposed of an positive electrode active material that occludes and liberates lithium ions, a negative electrodehaving a metallic collectorcoated with a negative electrode mixture, composed of a negative electrode active material that occludes and liberates lithium ions, and a separatorinterposed between the positive electrode and the negative electrode, wherein the positive electrodehas an insulating layerformed by means of the dried coating method, the heat seal tape method, or the hot melt coating method on a portion of the metallic collectorwhich is uncoated with the positive electrode mixtureand opposed to the negative electrodecoated with the negative electrode mixture, through the separator

Non-aqueous electrolyte secondary battery and manufacturing methods of an electrode used therein

An electrode plate for a secondary battery is provided for reducing adverse influences caused by paste of an insulating sheet in an electrode body and a battery specification. Active material layerstoand 22' to&#x2032; are formed on at least one surface of an electrode sheetover a wider range than a predetermined width of an electrode and over a predetermined length. An insulating sheetis made to adhere to a possible short-circuit portion of the electrode sheetwhich portion is opposed to another electrode. The electrode sheetand an insulating member are simultaneously cut to form an electrode plate having a predetermined shape, wherein the insulating member has a low-temperature thermoplastic paste material applied on one side thereof, and is made to adhere to the electrode sheetthrough heat adhesion.

Electrode plate for secondary battery, method of manufacturing the same, and secondary battery using the same

In the method for manufacturing the battery module according to this invention, after a pair of welding upper/lower electrodes or are arranged in contact on the cases of adjacent unit cells of a plurality of unit cells aligned in a line, a welding current is passed between the pair of welding upper electrodes from a welding power source while both ends of the unit cells are pressurized by pressurizing members under a prescribed pressure. Thus, Joule heat is generated at the contact portion between the bottom of the outer case of the unit cell and the positive polarity terminal of the unit cell so that the contact portion melts. Accordingly, the bottom of the outer case of the unit cell and the positive polarity terminal of the unit cell are welded to each other at the contact portion.

Method and apparatus for manufacturing battery module and unit battery cell for use in battery module

A battery module of the present invention comprises an annular connecting member having an aperture at a position corresponding to a cap provided on a sealing plate and between the sealing member of one cell B and a bottom of a can of the other cell A. The annular connecting member comprises an annular base portion having its outer diameter smaller than an inner diameter of the opening portion of the can , a convex portion with bottom protruding upward or downward alternately from the annular base portion , and a projection projecting from the bottom of the convex portion . Thereby, the connecting portion between the cell A and the cell B has a collecting path of a length between both projections , namely, a length between the sealing plate of the cell B and the bottom of the can of the cell A, whereby the voltage drop across the connecting portion decreases, resulting in a battery module having high operation voltage.

Battery module and method of manufacturing thereof

Growing community of inventors

Sumoto, Japan

Yoshinobu Okumura