Greatbatch Ltd.

Xiangyang Steve Dai

Mark J Roy

Gary Freitag

Robert S Rubino

Kenneth L Grubb

Robert D Miller

Paul T Hallifax

Kenneth B Talamine

Brian D Panzer

Lou Serpe

Gregory A Voss

A new weld configuration is used to obtain a robust and consistent resistance weld between the tabs of an anode current collector and the casing of an electrochemical cell. This is done by adding a resistive transferable electrode tip between at least one of the welding electrodes, preferably the movable welding electrode, and the stacked parts that are being joined together. The purpose of the transferable electrode tip is to generate a sufficient amount of heat during the welding process so that the stacked parts are joined together without adding any product functionality. In one embodiment of the present invention, the transferrable electrode tip is a stainless-steel ball, the stacked anode current collector tabs are of nickel, and the cell casing is of stainless-steel.

Transferable electrode tip for resistance welding an anode tab to the casing of an electrochemical cell

An electrochemical cell, preferably a secondary, rechargeable cell, including a casing comprised of a main body portion having opposed lower and upper open ends closed by respective lower and upper lids is described. The main body portion is composed of titanium Grades 5 or 23 having a relatively high electrical resistivity material while the lower and upper lids are composed of titanium Grades 1 or 2. The lids are preferably joined to the main body portion using laser welding. The combination of these differing titanium alloys provides a cell casing that effectively retards eddy current induced heating during cell recharging.

Method of providing an electrochemical cell casing having an open-ended main body portion of grade 5 or 23 titanium closed by upper and lower lids of grade 1 or 2 titanium

Electrochemical cell casing having an open-ended main body portion of grade 5 or 23 titanium closed by upper and lower lids of grade 1 or 2 titanium

A process for creating a laser braze weld joint between a current collector and a terminal pin in the construction of electrochemical cells is described. The laser braze welding process utilizes a laser weld instrument to create a braze-like joint between two work pieces. The weld joint is created by controlling the amount of laser heat and energy imparted to the work pieces through proper control and positioning of the laser beam with respect to the work pieces. Preferably, the method is used to bond the terminal pin to the cathode current collector. This method of attachment is suitable for either primary or secondary cells, particularly those powering implantable biomedical devices.

Connector from the tab of an electrode current collector to the terminal pin of a feedthrough in an electrochemical cell

An electrochemical cell comprising an electrode assembly having a plurality of cathodes in which the plurality of cathodes is electrically connected together at a connection tab junction is disclosed. The junction preferably comprises a plurality of cathode connection tabs that are folded over each other to construct a junction that is mechanically and electrically robust. The junction is comprised of a plurality of connection tabs that each extend from a cathode. Each of the respective tabs is folded over each other to form a compact electrode junction having redundant connections. An elongated lead extends from the junction to provide an electrical connection to the plurality of cathodes. The junction is welded together such as by a laser, resistance or ultrasonic weld joint. The cathode junction is suitable for either primary or secondary cells, particularly those powering implantable biomedical devices.

Electrochemical current collector screen designs utilizing ultrasonic welding

An electrode used for resistance welding is described. In an embodiment, the electrode comprises a two-part construction having an electrode tip portion that is removably contactable to an electrode base. The electrode is constructed such that the respective base and electrode tip portions may be composed of metals having differing melting temperatures, in particular a significant difference in melting temperature of at least 100&#xb0; C. or more. The electrode is preferably constructed so that the electrode tip portion can be easily removed, thereby leaving the base portion within the fixture.

Sacrificial resistance weld electrode

The present invention is directed to an electrochemical cell having plate electrodes housed inside a mating 'clamshell' casing. When mated together, the casing components are form-fitting with respect to the internal battery structure so as to reduce the overall size of the electrochemical package. A header assembly containing both a glass-to-metal seal opening for a terminal lead and an electrolyte fill opening is used in conjunction with the clamshell casing. The electrolyte fill opening is constructed with an elongated opening with at least two different radii. A first and second sealing element is welded within the electrolyte fill opening at different depths within the header to block the flow of electrolyte and form a hermetic seal.

Dual weld plug for an electrochemical cell

A direct welding process for joining a current collector to a terminal pin in the construction of electrochemical cells is described. The resistance welding process utilizes increased current combined with an applied force to bond dissimilar metals with a melting temperature differential of preferably more than 500&#xb0; C. Preferably, the method is used to bond the terminal pin to the cathode current collector. This method of attachment is suitable for either primary or secondary cells, particularly those powering implantable biomedical devices.

Method of direct resistance welding&#x2014;self brazing of aluminum to molybdenum pin

A magnetic pulse welding process for joining a current collector to a terminal pin in the construction of electrochemical cells is described. The magnetic pulse welding process utilizes a pulsed direct current and an electrically conductive coil to generate an electro-magnetic force that causes two work pieces to collide with each other and form a bond therebetween. Preferably, the method is used to bond the terminal pin to the cathode current collector. This method of attachment is suitable for either primary or secondary cells, particularly those powering implantable biomedical devices.

Magnetic pulse welding in medical power manufacturing

An ultrasonic welding process for joining a current collector to an anode or cathode material of electrochemical cells is described. The ultrasonic welding process utilizes an ultrasonic welding frequency which may be combined with an applied force to bond dissimilar metals comprising the electrode material and the current collector. Preferably, the method is used to bond the anode material to the anode current collector. This method of attachment is suitable for either primary or secondary cells, particularly those powering implantable biomedical devices.

Ultrasonic welding of lithium onto a current collector

A fixture in which an attractive magnetic force is utilized to join two parts of a container or housing together is discussed. The fixture comprises a fixture body portion, a fixture base portion and a removable fixture plate portion. At least one body magnet resides within the fixture body portion and at least one plate magnet resides within the removable fixture plate. The fixture body and plate magnets are positioned such that when they are brought together, an attractive magnetic force pulls the plate towards the fixture body. Therefore, when the respective housing portions are positioned within the fixture, the magnetic force compresses the housing portions together.

Growing community of inventors

Saginaw, MI, United States of America

Xiangyang Steve Dai