Johns Hopkins University

United States of America as Represented by the Secretary of the Air Force

Terry E Phillips

Rengaswamy Srinivasan

Richard C Benson

Bliss G Carkhuff

Harvey Wayne Ko

Micah A Carlson

Charles W Anderson

Allan B Fraser

Joseph Bohandy

Boris F Kim

Hassan M Saffarian

David R Kohler

Frank J Adrian

Kishin Moorjani

C Brent Bargeron

John D Groopman

Paul T Strickland

Jay C Poret

Joseph J Suter

Jason E Tiffany

Paul R Zarriello

Jeremy D Walker

Lawrence W Hunter

Thomas R Sanderson

Oscar M Uy

Subhas Chalasani

Andrew C Baisden

John A Thomas

Michael H Butler

Michael L Butler

Methods and systems to determine an internal temperature of a rechargeable lithium-ion cell based on a phase shift of the cell. Internal cell temperature may be determined with respect to an internal anode temperature and/or an internal cathode temperature. Internal anode temperature may be determined based on a phase shift of a frequency within a range of approximately 40 Hertz (Hz) to 500 Hz. Internal cathode temperature may be determined based on a phase shift of a frequency of up to approximately 30 Hz. A temperature sensor as disclosed herein may be powered by a monitored cell with relatively little impact on cell charge, may be electrically coupled to cell but housed physically separate from the cell, and/or may monitor multiple cells in a multiplex fashion. A rate of change in phase shift may be used to initiate pre-emptive action, without determining corresponding temperatures.

Battery phase meter to determine internal temperatures of lithium-ion rechargeable cells under charge and discharge

A time-temperature indication device includes a first reservoir having a fluid disposed therein, and a capillary tube. The capillary tube is disposed proximate to the first reservoir to receive fluid from the first reservoir responsive to changes in viscosity of the fluid based on changes in temperature. The capillary tube restricts flow of the fluid out of the first reservoir into the capillary tube to enable fluid flow only in a single direction.

Time-temperature indicator

A battery health monitor (BHM) that operates as a battery-mountable full-spectrum alternating current (ac) impedance meter that facilitates monitoring a state-of-charge and a state-of-health of a battery. The BHM is used for monitoring one or more electrical parameters, e.g., impedance, of a battery. The BHM includes: a current sink coupled to the first terminal and configured to sink therefrom an oscillatory current so as to cause the battery to produce at a first terminal thereof an oscillatory voltage equal to or less than a dc operating voltage of the battery that would be present at the first terminal in the absence of the oscillatory current; and a voltage sensor configured to sense the oscillatory voltage at the first terminal.

Battery health monitor

An embeddable corrosion rate meter (ECRM) for detecting and measuring corrosion in metal and concrete structures is provided. The system comprises an electrochemical cell with at least one working electrode evenly separated from a counter electrode, wherein a separation distance between electrodes determines an electrolyte medium resistance and the electrolyte medium resistance is less than or equal to a polarization resistance. The system further includes a signal generator connected to a plurality of resistances for creating a plurality of current amplitudes for generating a current source; a first selector for applying a current through each of the plurality of resistances to the working electrode and counter electrode; a second selector for selecting a duration of a current pulse; a voltmeter/A-D converter having an input impedance &#x3e;10ohms for measuring polarization of the working electrode; and an external reader-head with a data link and power link connected to a computing device for powering the system and collecting corrosion measurements data.

Embeddable corrosion rate meters for remote monitoring of structures susceptible to corrosion

A hand held, self-contained, automatic, low power and rapid sensor platform for detecting and quantifying a plurality of analytes. A sample solution potentially containing an unknown amount of an analyte is passed through an affinity column which contains antibodies to which the analyte binds thereby extracting the analyte. The affinity column is then rinsed to remove any other chemicals that may fluoresce. The rinsed affinity column is then eluted with a known volume of elution fluid causing the analyte to release from the antibody and dissolve in the fluid (eluant). The eluant is then placed in the quartz cuvette of a fluorometer. The analyte suspended in the eluant fluoresces at a waveband which is different than that of the light source that excites it. The amount of fluorescence is measured and the level of analyte determined. The rinsing and elution fluids, and/or the affinity column can be placed in a module for easy insertion and removal from the sensor when depleted or when the sensor is to be used against a different analyte.

Miniature immuno-optical rapid analyte sensor platform

A pair of interleaved finger-like electrodes are positioned over a pyro-electric sheet of polyvinylidine fluoride and a pair of coatings are formed upon the electrodes having different optical reflectance, and as a result, a light beam energy absorption differential will be produced between the coatings and the resulting change in temperature in the sheet material under the electrodes will cause a voltage to be generated. A differential amplifier is connected across the electrodes to sense this voltage, indicative of the detection of an incoming laser light beam. A light chopper is positioned to interrupt the light beam directed at a portion of the pyro-electric sheet.

Narrow band optical radiation sensor using pyroelectric material

Weak links in superconductors are detected by observing the effect of magnetic field modulation on the microwave resistance of superconductors. The phase detected response to the magnetic modulation can show a peak at T.sub.c. The presence of peak(s) at temperatures below T.sub.c indicates the presence of weak links in the superconductor.

Microwave method for detection of weak links in superconductors

Weak links in electrically continuous superconductors are detected by observing the effect of magnetic field modulation on the dc resistance of superconductors. The phase detected response to the magnetic modulation shows a peak at T.sub.c. The presence of a second peak at temperatures below T.sub.c, and concomitantly the appearance of a tail on the low temperature end of the dc resistance vs temperature curve indicates the presence of weak links in the superconductor.

Method for detection of weak links in the current path of electrically

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Ellicott City, MD, United States of America

Terry E Phillips