Sanyo Electric Co., Ltd.

Tooru Amazutsumi

Yasuhiro Yamauchi

Satoshi Narukawa

Mitsunori Hara

Hiyoshi Tamaki

Kenji Kawaguchi

Mikitaka Tamai

Toyoji Machida

Kazuro Moriwaki

Seiji Morita

Hideki Fukuda

Hideki Kishi

Hidenori Tsuda

Nobuaki Masaki

Keiichi Tsujioku

Nobuhiro Nagao

Kanji Urushihara

Hideyuki Nagaya

Syouzaburou Saji

In a residual capacity correction method for a battery, a count of one cycle is made each time an accumulated quantity of a charge capacity of a battery reaches a learning capacity of the battery at that time, and the learning capacity is decreased by a specified cycle degradation capacity per charge of the one cycle, alternatively a decreasing rate of the learning capacity is specified as a keeping degradation capacity while a keeping temperature and a residual capacity of the battery are used as parameters, and as a keeping time passes, the learning capacity is decreased by the keeping degradation capacity specified from the keeping temperature and the residual capacity of the battery.

Residual capacity correction method for battery

A battery is provided which includes: an electrode roll having a positive-electrode plate, a negative-electrode plate and a separator interposed therebetween; a battery casing accommodating the electrode roll; and a sealing plate laser-welded to an open end of the battery casing. On the outermost periphery of the electrode roll is located an electrode-base-exposed portion of either one of the positive-electrode plate and the negative-electrode plate. The sealing plate is laser-welded to the battery casing in a state that a collector tab formed by incising the electrode-base-exposed portion and folding the incised portion is held between the periphery of the open end of the battery casing and the sealing plate. With this construction, the electrical connection between the collector tab and the battery casing is assuredly achieved simultaneously with the sealing of the battery to suppress a reduction in the closed-circuit voltage and an increase in the internal resistance. In addition, the battery of this construction can be fabricated by a simplified battery fabrication process.

Laser-sealed battery

The outside edges of a sealing plate are weld attached to close off an opening in a metal case of a prismatic battery of this invention. The sealing plate has an electrode rivet which passes through an electrode hole and sandwiches an insulating gasket to attach in an electrically insulating fashion. The battery case houses an electrode group with either its positive or negative electrode plate connected to the electrode rivet. The sealing plate has a periphery region or reinforcement rib which is formed thicker than the rivet region where the electrode rivet attaches, and the outside edges of this reinforcement rib are weld attached to the case.

Prismatic battery

A charging apparatus charges a secondary battery in alternating charging and rest periods. The charge amount supplied in the charging periods is restricted to an amount which reduces or eliminates deterioration of the secondary battery by overcharging.

Secondary battery charger

A nonaqueous electrolyte battery has a positive electrode, a negative electrode and separator laminate rolled into a spiral electrode unit contained in an external case filled with nonaqueous electrolyte. Battery voltage is between 3.5 V and 5.0 V when charged. A positive electrode supporting member material and the external case are both aluminum. The positive Electrode supporting member is exposed for at least a portion of the outermost winding of the spiral electrode unit, and this exposed supporting member contacts the inner surface of the external case to make an electrical connection.

Nonaqueous electrolyte battery

The present invention relates an enclosed cell and fabricating methods of the cell which has a safety valve mechanism for releasing gas from inside the cell when an internal pressure of the cell rises to an excessive degree. The characterizing feature of the invention resides in the use of a resin packing as sealing element, junctions between the resin packing and a metal lid and between the resin packing and a polar terminal being closed tight by thermal fusion. This construction assures reliable sealing in normal state, and permits the packing to break with an excessive rise in the internal pressure thereby to release gas from inside the cell. The cell of this invention is readily fabricated by injection molding or by a hot press process. Therefore, the enclosed cell according to this invention is fabricated very rationally and inexpensively, assures excellent sealing and safety, and has wide application.

Enclosed cell having safety valve mechanism and fabricating method of

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Tsuna-gun, Japan

Tooru Amazutsumi