Medtronic, Inc.

Medtronics, Inc.

Ann M Crespi

William G Howard

Paul M Skarstad

Douglas J Weiss

Kaimin Chen

John Daniel Norton

Darrel F Untereker

Roger W Kelm

Fred J Berkowitz

Kevin Chen

Andrew J Ries

Craig L Schmidt

John D Wahlstrand

Joachim Hossick-Schott

James W Busacker

David P Haas

Gregory A Younker

Frank A Duva

Anthony R Rorvick

Jenn-Feng Yan

John W Cretzmeyer

Steven G Rockow

Fred J Berkcwitz

System and method for estimating a remaining capacity of a battery of an implantable medical device. The implantable medical device has a battery producing a current and having a remaining battery capacity, the implantable medical device being configured to utilize a relatively low amount of the current and, in specific instances, a relatively large pulse of the current. The processor is coupled to the battery and configured to calculate an estimate of the remaining battery capacity based, at least in part, on a measured battery parameter and occurrences of the specific instances of delivery of the relatively large pulse of the current.

Battery longevity estimator that accounts for episodes of high current drain

Methods for estimating a remaining service life of an implantable medical device (IMD) battery are presented. In one embodiment, a characteristic discharge model of the battery is employed. Systems employing the methods may include an external device coupled to the IMD, for example, via a telemetry communications link, wherein a first portion of a computer readable medium included in the IMD is programmed to provide instructions for the measurement, or tracking, of time and the measurement of battery voltage, and a second portion of the computer readable medium included in the external device is programmed to provide instructions for carrying out the calculations when the voltage and time data is transferred via telemetry from the IMD to the external device.

Estimating remaining battery service life in an implantable medical device

Wet-tantalum capacitors used in a medical device are charged to and maintained at a maintenance voltage between full energy charges so that deformation in the wet-tantalum capacitor is substantially inhibited.

Method of maintaining wet-tantalum electrolytic capacitors

An improved manufacturing and packaging process for optimizing the size of various implanted medical devices is disclosed. Specifically, complex shapes involving ceramic capacitors with various other shapes are manufactured to optimize fit and shapes within the device housing. The manufacturing process includes various techniques and electrode material selections, including manufacturing processes that enable high energy discharge capacitors to be made in compliant shapes to fit in small ICD footprints.

Complex-shaped ceramic capacitors for implantable cardioverter defibrillators and method of manufacture

Methods are provided for manufacturing an electrode. In one exemplary embodiment, the method includes the steps of contacting the silver layer with vanadium oxide, and heating the silver layer and vanadium oxide in an oxygen-containing atmosphere to form a silver vanadium oxide layer chemically bonded to the metal substrate.

High capacitance low resistance electrode

Implantable medical devices (IMDs) and their various components, including flat electrolytic capacitors for same, and methods of making and using same, particularly an improved electrolytic capacitor with optimized ESR and anode layer surface area. An electrode stack assembly and electrolyte are located within the interior case chamber of a hermetically sealed capacitor case. The electrode stack assembly comprises a plurality of capacitor layers stacked in registration upon one another, each capacitor layer comprising a cathode layer having a cathode tab, an anode sub-assembly comprising at least one anode layer having an anode tab, and a separator layer located between adjacent anode and cathode layers, whereby all adjacent cathode layers and anode layers of the stack are electrically insulated from one another by a separator layer. Anode terminal means extend through the capacitor case side wall for electrically connecting a plurality of the anode tabs to one another and providing an anode connection terminal at the exterior of the case. Cathode terminal means extend through or to an encapsulation area of the capacitor case side wall for electrically connecting a plurality of the cathode tabs to one another and providing a cathode connection terminal at the exterior of the case. A connector assembly is electrically attached to the anode connection terminal for making electrical connection with the anode tabs and to the cathode connection terminal for making electrical connection with the cathode tabs. The anode layers are formed of one or more nonthrough-etched anode sheet bearing an oxide layer and formed with a plurality of punctures therethrough.

Implantable medical device having flat electrolytic capacitor formed with nonthrough-etched and through-hole punctured anode sheets

An electrochemical cell and electrode assembly in which an alkali metal anode and a cathode assembly are wound together in a unidirectional winding having substantially straight sides such that the winding will fit into a prismatic cell. The anode and cathode are arranged in the winding to provide for even utilization of reactive material during cell discharge by placing cathode and anode material in close proximity throughout the electrode assembly in the proportions in which they are utilized. The winding also contributes to even utilization of reactive material by employing multiple tabs on the cathode assembly to ensure that cathode material is evenly utilized throughout the electrode assembly during cell discharge and also so that connections to the tabs are readily made.

High reliability electrochemical cell and electrode assembly therefor

The invention provides heat-treated silver vanadium oxide for use in the cathodes of electrochemical cells, particularly in implantable medical devices. The heat-treated silver vanadium oxide is capable of being pressed into a pellet having a pressed pellet density of about 3.10 g/cm.sup.3 to about 3.45 g/cm.sup.3 when about 2 grams of the heat-treated silver vanadium oxide are uniaxially pressed into a pellet using a 1.6 cm diameter cylindrical die with a 7500 pound force applied for 5 seconds.

Heat treated silver vanadium oxide for use in implantable medical

This present invention provides a method for forming C-SVO without the need for flowing O.sub.2 during its synthesis. A method of forming silver vanadium oxide in accordance with the present invention includes combining AgO with a vanadium-containing compound to form a mixture; and exposing the mixture to a sufficient temperature for a time effective to form silver vanadium oxide. A method of forming the silver vanadium oxide for use as a cathode material is disclosed.

Synthesis of silver vanadium oxide for cathode material

Method for making a high reliability electrochemical cell and electrode

A high rate battery having a coiled electrode assembly housed in a case that efficiently utilizes the space available in many implantable medical devices is disclosed. The battery case provides a planar surface opposite an arcuate surface to allow for the close abutting of other components located within the implantable device while also providing for efficient location of the battery within an arcuate edge of the device. The battery cases include at least three planar sides extending between a top and a base of the battery case, wherein the arcuate side is located directly opposite one of the planar sides. The battery case may form a prismatic solid shape with one arcuate surface and five planar surfaces. The batteries may include a coiled electrode assembly including an anode and a cathode; electrolyte; and a case liner containing the electrode assembly. The coiled electrode assembly can have an elliptical cross-section including two arcuate ends, wherein one of the arcuate ends is nested within an arcuate side of the case. The batteries are capable of delivering about 20 joules or more in about 20 seconds or less; and may also be capable of delivering about 20 joules or more at least twice in a period of about 30 seconds. Also included are implantable defibrillator devices incorporating the batteries and methods of manufacturing the batteries including drawing the battery case from metal.

Volumetrically efficient battery for implantable medical devices

An electrochemical cell containing a cathode comprising silver vanadium oxide and an anode comprising lithium is disclosed that includes an improved electrolyte composition having the solvents propylene carbonate and 1,2-dimethoxyethane, and an additional third solvent that reduces the solubility of the composition of the silver vanadium cathode material. Preferably, the third solvent is a dialkyl carbonate such as dimethyl carbonate, diethyl carbonate or ethylmethyl carbonate. The improved electrolyte composition reduces the build up of resistance in the cell during cell discharge, and may affect the cell's performance in implantable cardiac defibrillator applications. The cell of the present invention may include a hybrid cathode containing a mixture of silver vanadium oxide and carbon monofluoride (CF.sub.x).

Growing community of inventors

Minneapolis, MN, United States of America

Ann M Crespi