Abstract:
Disclosed herein are electrochemical cells that generally relate to the conversion of chemical energy to electrical energy. More particularly, the present disclosure is directed to primary lithium electrochemical cells possessing insulator pocket structures, which substantially envelope cathode components to prevent lithium cluster formation therein.
Abstract:
A lithium electrochemical cell with increased energy density is described. The electrochemical cell comprises an improved sandwich cathode design with a second cathode active material of a relatively high energy density but of a relatively low rate capability sandwiched between two current collectors and with a first cathode active material having a relatively low energy density but of a relatively high rate capability in contact with the opposite sides of the two current collectors. In addition, a cathode fabrication process is described that increases manufacturing efficiency. The cathode fabrication process comprises a process in which first and second cathode active materials are directly applied to opposite surfaces of a perforated current collector and laminated together. The present cathode design is useful for powering an implantable medical device requiring a high rate discharge application.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
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.
Abstract:
A current collector for an electrochemical cell is described. Unlike conventional current collector designs, the current collector does not have an unperforated perimeter frame completely bordering or surrounding a perforated interior region. Instead, only that portion of the current collector adjacent to the connector tab is unperforated. Otherwise, perforations extend directly to the perimeter edge.
Abstract:
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.