Hrl Laboratories, LLC

Gm Global Technolgoy Operations, Inc.

Souren Soukiazian

John S Wang

Shuoqin Wang

Ping Liu

Mark William Verbrugge

Jason A Graetz

Elena M Sherman

Tina T Salguero

Jocelyn Hicks-Garner

Brian James Koch

Chia-Ming Chang

Alok Warey

Jing Gao

Alfred Zhang

Daniel M Zehnder

Patrick J Webb

A vehicle, and a balancing device and method of controlling a state of charge of a reference electrode in a battery. The balancing device includes a measurement circuit and a charging circuit. The measurement circuit is configured to obtain a measurement of a reference voltage of the reference electrode. The charging circuit is configured to adjust the reference voltage based on the measurement. The state of charge of the reference electrode is controlled based on the reference voltage.

Automated reference electrode management

In some variations, a method of real-time monitoring of battery capacity comprises correlating electrode open-circuit voltage with electrode state of charge for a selected electrode; compiling a look-up table to correlate the electrode open-circuit voltage with the electrode capacity at different values of the active-material capacity; during real-time operation, identifying first and second times at which battery terminal voltages are approximated as battery open-circuit voltages; and calculating battery capacity based on the difference in battery open-circuit voltages at the first and second times, current integration, and the look-up table. No reference electrode is needed, and a complete battery charge/discharge is not necessary to determine the capacity. This technique can therefore be implemented on-board and in real time to provide reliable capacity estimation even as the battery ages. The methods are applicable to various metal-ion secondary battery systems, including lithium-ion batteries, with different material chemistries.

Methods for online estimation of battery capacity and state of health

The internal temperature of an electrochemical device may be probed without a thermocouple, infrared detector, or other auxiliary device to measure temperature. Some methods include exciting an electrochemical device with a driving profile; acquiring voltage and current data from the electrochemical device, in response to the driving profile; calculating an impulse response from the current and voltage data; calculating an impedance spectrum of the electrochemical device from the impulse response; calculating a state-of-charge of the electrochemical device; and then estimating internal temperature of the electrochemical device based on a temperature-impedance-state-of-charge relationship. The electrochemical device may be a battery, fuel cell, electrolytic cell, or capacitor, for example. The procedure is useful for on-line applications which benefit from real-time temperature sensing capabilities during operations. These methods may be readily implemented as part of a device management and safety system.

Methods and apparatus for sensing the internal temperature of an electrochemical device

The disclosed battery system comprises a three-electrode metal-ion battery configured with voltage meters connected between anode and cathode, between anode and a reference electrode, and between cathode and the reference electrode; a current source connecting the anode and cathode; and a programmable computer. The system is configured to control the current source to drive the battery with a current cycling profile, and to measure current signals between anode and cathode, and voltage signals derived from the voltage meters. An impulse response is then calculated for each of the anode and cathode, to dynamically estimate open-circuit potential and impedance of each of the anode and cathode. Battery aging, battery capacity fading, and other diagnostics are provided in real time. This invention can characterize each individual electrode of a battery, even when the battery is cycling away from equilibrium states, which is important for electric vehicles.

Methods and apparatus for real-time characterization of batteries with a reference electrode

In some variations, an apparatus provides real-time monitoring of voltage and differential voltage of both anode and cathode in a battery configured with at least one reference electrode. Voltage monitors are connected to a computer programmed for receiving anode voltage signals; receiving cathode voltage signals; calculating the derivative of the anode voltage with respect to time or with respect to capacity; and calculating the derivative of the cathode voltage with respect to time or with respect to capacity. Other variations provide an apparatus for real-time assessment of capacities of both anode and cathode in a battery, comprising a computer programmed for receiving electrode voltage signals; estimating first and second electrode open-circuit voltages at two different times, and correlating the first and second electrode open-circuit voltages to first and second electrode states of charge, respectively, for each of anode and cathode. The anode and cathode capacities may then be estimated independently.

Voltage protection and health monitoring of batteries with reference electrodes

A lithium-ion battery structure with a third electrode as reference electrode is disclosed. The reference electrode may be fabricated from lithium metal, lithiated carbon, or a variety of other lithium-containing electrode materials. A porous current collector allows permeation of reference lithium ions from the reference electrode to the cathode or anode, enabling voltage monitoring under actual operation of a lithium-ion battery. The reference electrode therefore does not need to be spatially between the battery anode and cathode, thus avoiding a shielding effect. The battery structure includes an external reference circuit to dynamically display the anode and cathode voltage. The battery structure can result in improved battery monitoring, enhanced battery safety, and extended battery life.

Battery with reference electrode for voltage monitoring

This invention provides batteries with improved calendar and cycle lifetimes. A rechargeable battery comprises an additional electrode that includes active ions, such as lithium ions. Cell capacity of the battery can be increased by supplying these active ions to the anode or the cathode. In some variations, this invention provides a lithium-ion battery comprising an anode, a cathode, an electrolyte, and an additional lithium-containing electrode, wherein the additional lithium-containing electrode is capable of supplying lithium ions to the anode or the cathode in the presence of an electrical current.

Batteries with replenishable storage capacities

A method and an apparatus is provided for increasing biofilm formation and power output in microbial fuel cells. An anode material in a microbial fuel cell has a three-dimensional and ordered structure. The anode material fills an entire anode compartment, and it is arranged to allow fluid flow within the anode compartment. The power output of microbial fuel cells is enhanced, primarily by increasing the formation and viability of electrogenic biofilms on the anodes of the microbial fuel cells. The anode material in a microbial fuel cell allows for the growth of a microbial biofilm to its natural thickness. In the instance of members of the Geobacteraceae family, the biofilm is able grow to a depth of about 40 microns.

Methods and apparatus for increasing biofilm formation and power output in microbial fuel cells

A method for monitoring a lithium-ion battery cell includes monitoring a battery cell voltage and a corresponding charge capacity of the battery cell during an electric power event which may include either an electric power charge event or an electric power discharge event. A measured charge-capacity-derivative is determined by differentiating the charge capacity in relation to the corresponding battery cell voltage during the electric power event. The measured charge-capacity-derivative is compared with a preferred anode charge-capacity-derivative of an anode charge curve (for electric power discharge events) or an anode discharge curve (for electric power charge events), and with a preferred cathode charge-capacity-derivative of a cathode charge curve (for electric power charge events) or a cathode discharge charge curve (for electric power discharge events). A first state of health parameter of the battery cell corresponding to the comparison of the measured charge-capacity-derivative with the preferred anode charge-capacity-derivative of the anode curve is determined. And, a second state of health parameter of the battery cell corresponding to the comparison of the measured charge-capacity-derivative with the preferred cathode charge-capacity-derivative of the cathode curve is determined.

Method and apparatus for assessing battery state of health

A method for monitoring a lithium-ion battery cell includes monitoring a battery cell voltage and a corresponding state of charge of the battery cell during an electric power event which may include either an electric power charge event or an electric power discharge event. A measured potential-derivative is determined by differentiating the battery cell voltage in relation to the corresponding state of charge of the battery during the electric power event. The measured potential-derivative is compared with a preferred anode potential-derivative of an anode charge curve (for electric power discharge events) or an anode discharge curve (for electric power charge events), and with a preferred cathode potential-derivative of a cathode charge curve (for electric power charge events) or a cathode discharge charge curve (for electric power discharge events). A first state of health parameter of the battery cell corresponding to the comparison of the measured potential-derivative with the preferred anode potential-derivative of the anode curve is determined. And, a second state of health parameter of the battery cell corresponding to the comparison of the measured potential-derivative with the preferred cathode potential-derivative of the cathode curve is determined.

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Burbank, CA, United States of America

Souren Soukiazian