Sanyo Electric Co., Ltd.

Toru Amazutsumi

Satoshi Narukawa

Yasuhiro Yamauchi

Hiyoshi Tamaki

Hideki Fukuda

Kazuro Moriwaki

A piece of portable electric equipment is provided with a case, a battery pack housed in the case, and an input/output (I/O) connector which is exposed outside the case and has charging terminals. The I/O connector is accessible inside the case and has connecting terminals which contact battery terminals on the battery pack housed in the case. The portable electric equipment case holds the battery pack with its battery terminals in direct contact with the connecting terminals of the I/O connector.

Battery carrying portable electric equipment

A method of manufacturing a battery containing a non-circular spiral electrode unit forms a true circular or elliptical cylindrical electrode unit by winding positive and negative electrode plates with a micro-porous polymer film separator disposed between the two electrode plates. The cylindrical electrode unit is pressed from both sides into a non-circular spiral electrode unit and inserted into an external case to form a battery. When the cylindrical electrode unit is pressed into a non-circular spiral electrode unit, the separator gurley value of the pressed non-circular spiral electrode unit is arranged to be in the range from 110% to 150%, where the separator gurley value of the cylindrical electrode unit is 100%.

Method of manufacturing a battery containing a non-circular spiral

The battery of the present invention includes a case, an electrode group introduced into the case and a cover sealing the open side of the case. The cover has a battery electrode, an insulation panel, spacers, and a cover tab, fixed thereto. The battery electrode and the cover tab are electrically welded, and are insulated from the cover. The spacers and the insulation panel are made of an insulating material. A connection opening is formed between the introduction of the spacers and enables welding material to weld the cover tab to the electrode group.

Battery with a spacer between the electrode group and the cover

Corner region vacancies resulting from insertion of a spiral electrode unit into a prismatic can are fully utilized to reinforce the can and produce superior battery characteristics. A non-circular spiral electrode unit is made by rolling a negative electrode-separator-positive electrode sandwich. A prismatic shaped can has corners which are thicker than the straight-line regions of the can. The can houses the the electrode unit In a tightly sealed fashion with the outer winding of the electrode unit mechanically held in electrical contact with the can.

Tightly sealed prismatic battery

Novel lead location and winding configuration allow more efficient spiral electrode fabrication for a battery that is less susceptible to internal short circuits. The battery has separator material sandwiched between positive and negative electrode strips, which are rolled into a spiral electrode unit. The electrodes have active material that covers a core except in regions where leads are attached. One lead is positioned at the outermost winding, and both sides of each lead face either separator material only or the same polarity electrode via separator material. A special lead taping processing step is eliminated.

Growing community of inventors

Tsuna-gun, Japan

Toru Amazutsumi