# US 2019/0170829 A1 · Battery Cell Evaluation System > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0170829 A1 - Document ID: US20190170829A1 - Status: Published application - Kind: A1 - Application number: 16/210,648 - Filed: 2018-12-05 - Published: 2019-06-06 - Earliest claimed: 2017-12-06 - Assignees: The Johns Hopkins University - Applicants: The Johns Hopkins University - Inventors: Rengaswamy Srinivasan; Bliss G. Carkhuff - Web page: https://patentgrep.com/patent/US20190170829A1 ## CPC - G01R 31/389: Measuring internal impedance, internal conductance or related variables - G01R 31/3648: {comprising digital calculation means, e.g. for performing an algorithm} - G01R 31/396: Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) ## Abstract An example battery cell diagnostic apparatus is provided that may include control circuitry, a current source, measurement circuitry, and a first and a second multiplexer. The control circuitry may be configured to control the first multiplexer to electrically connect the measurement circuitry to a battery cell and control the second multiplexer to electrically connect the current source to the battery cell to apply a current, output from the current source, at each of a set of frequencies to the battery cell. The control circuitry may also be configured to receive measurements from the measurement circuitry at each of the frequencies, which may include respective frequencies that correlate to an electrolytic resistance of the battery cell, an anode impedance of the battery cell, and a cathode impedance of the battery cell. Similar measurements may also be taken for each cell in a battery. ## Claims ### Claim 1 A battery cell diagnostic apparatus comprising: control circuitry; a current source; measurement circuitry configured to measure electrical attributes of a battery cell among a plurality of battery cells and provide measurements of the electrical attributes to the control circuitry; a first multiplexer operably coupled to the measurement circuitry and the control circuitry, the first multiplexer being configured to be removably coupled to each of the battery cells within the plurality of battery cells; and a second multiplexer operably coupled to the current source and the control circuitry, the second multiplexer being configured to be removably coupled to each of the battery cells within the plurality of battery cells; wherein the control circuitry is configured to: control the first multiplexer to electrically connect the measurement circuitry to the battery cell among the plurality of battery cells; control the second multiplexer to electrically connect the current source to the battery cell to apply a current, output from the current source, at each of a set of frequencies to the battery cell; receive the measurements from the measurement circuitry corresponding to each of the frequencies within the set of frequencies, the set of frequencies including a first frequency that correlates to an electrolytic resistance of the battery cell, a second frequency that correlates to an anode impedance of the battery cell, and a third frequency that correlates to a cathode impedance of the battery cell; and store the measurements for the battery cell in a memory device. ### Claim 2 (depends on 2) The battery cell diagnostic apparatus of claim 2, wherein the control circuitry is further configured to determine, based on stored measurements for each of the battery cells, one or more groups of battery cells that have measurements that match within a threshold difference for each of the frequencies within the set of frequencies. ### Claim 3 (depends on 1) The battery cell diagnostic apparatus of claim 1, wherein the control circuitry is further configured to: determine, based on stored measurements for each of the battery cells, a group of battery cells that have measurements that match within a threshold difference for each of the frequencies within the set of frequencies; and in response to determining that one of the plurality of battery cells is not within the group, output an alert. ### Claim 4 (depends on 1) The battery cell diagnostic apparatus of claim 1, wherein the control circuitry is further configured to derive the anode temperature based on the anode impedance and derive the cathode temperature based on the cathode impedance. ### Claim 5 (depends on 1) The battery cell diagnostic apparatus of claim 1, wherein the first frequency is in a range between approximately 200 Hz and 1 kHz, the second frequency is in a range between approximately 40 Hz and 100 Hz, and the third frequency is in a range between approximately 5 Hz and 15 Hz. ### Claim 6 (depends on 1) The battery cell diagnostic apparatus of claim 1, wherein the measurements received from the measurement circuitry include amplitude measurements. ### Claim 7 A system for assessing attributes of battery cells, the system comprising: a plurality of battery cells, each battery cell having terminals; and a battery cell diagnostic apparatus comprising: control circuitry; a current source; measurement circuitry configured to measure electrical attributes of a battery cell among the plurality of battery cells and provide measurements of the electrical attributes to the control circuitry; a first multiplexer operably coupled to each of battery cells, the measurement circuitry, and the control circuitry; a second multiplexer operably coupled to each of the battery cells, the current source, and the control circuitry; wherein the control circuitry is configured to: control the first multiplexer to electrically connect the measurement circuitry to the battery cell; control the second multiplexer to electrically connect the current source to the battery cell to apply a current, output from the current source, at each of a set of frequencies to the battery cell; receive the measurements from the measurement circuitry corresponding to each of the frequencies within the set of frequencies, the set of frequencies including a first frequency that correlates to an electrolytic resistance of the battery cell, a second frequency that correlates to an anode impedance of the battery cell, and a third frequency that correlates to a cathode impedance of the battery cell; and store the measurements for the battery cell in a memory device. ### Claim 8 (depends on 7) The system of claim 7, wherein the battery cells within the plurality of battery cells are not electrically connected to each other. ### Claim 9 (depends on 7) The system of claim 7, wherein the control circuitry is further configured to determine, based on stored measurements for each of the battery cells, one or more groupings of battery cells that have measurements that match within a threshold difference for each of the frequencies within the set of frequencies. ### Claim 10 (depends on 7) The system of claim 7, wherein the battery cells are connected to each other to form a battery that operates as a power source to an electronic device; wherein the control circuitry is further configured to: receive a signal representing a diagnostic request to perform an evaluation process on each of the battery cells prior to providing operational power to the electronic device, wherein the evaluation process includes storing the measurements for the battery cell in the memory device; in response to receiving the signal, determine, based on stored measurements for each of the battery cells, a group of battery cells that have measurements that match within a threshold difference for each of the frequencies within the set of frequencies; and in response to determining that one of the plurality of battery cells is not within the group, prevent operational power to be provided to the electronic device or output an alert. ### Claim 11 (depends on 7) The system of claim 7, wherein the battery cells are electrically connected to each other to form a battery for subsequent installation into an electronic device to operate as a power source for the electronic device. ### Claim 12 (depends on 11) The system of claim 11, wherein electrical connections among the battery cells comprise welds. ### Claim 13 (depends on 7) The system of claim 7, wherein the control circuitry is further configured to derive the anode temperature based on the anode impedance and derive the cathode temperature based on the cathode impedance. ### Claim 14 (depends on 7) The system of claim 7, wherein the first frequency is in a range between approximately 200 Hz and 1 kHz, the second frequency is in a range between approximately 40 Hz and 100 Hz, and the third frequency is in a range between approximately 5 Hz and 15 Hz. ### Claim 15 A method for assessing attributes of battery cells, the method comprising: controlling, by control circuitry, a first multiplexer operably coupled to each battery cell within a plurality of battery cells to electrically connect measurement circuitry to a battery cell among the plurality of battery cells; controlling, by the control circuitry, a second multiplexer operably coupled to each battery cell within the plurality of battery cells to electrically connect a current source to the battery cell to apply a current, output from the current source, at each of a set of frequencies to the battery cell; receiving, at the control circuitry, measurements from the measurement circuitry corresponding to each of the frequencies within the set of frequencies, the set of frequencies including a first frequency that correlates to an electrolytic resistance of the battery cell, a second frequency that correlates to an anode impedance of battery cell, and a third frequency that correlates to a cathode impedance of the battery cell; and storing the measurements for the battery cell in a memory device. ### Claim 16 (depends on 15) The method of claim 15, wherein the battery cells within the plurality of battery cells are not electrically connected to each other. ### Claim 17 (depends on 15) The method of claim 15, further comprising determining, based on stored measurements for each of the battery cells, one or more groupings of battery cells that have measurements that match within a threshold difference for each of the frequencies within the set of frequencies. ### Claim 18 (depends on 15) The method of claim 15, wherein the battery cells are connected to each other to form a battery that operates as a power source to an electronic device; and wherein the method further comprises: receiving a signal representing a diagnostic request to perform an evaluation process on each of the battery cells prior to providing operational power to the electronic device, wherein the evaluation process includes storing the measurements for the battery cell in the memory device; in response to receiving the signal, determining, based on stored measurements for each of the battery cells, a group of battery cells that have measurements that match within a threshold difference for each of the frequencies within the set of frequencies; and in response to determining that one of the plurality of battery cells is not within the group, preventing operational power to be provided to the electronic device or outputting an alert. ### Claim 19 (depends on 15) The method of claim 15, wherein the battery cells are electrically connected to each other to form a battery for subsequent installation into an electronic device to operate as a power source for the electronic device. ### Claim 20 (depends on 15) The method of claim 15, wherein the measurements provided by measurement circuitry include a battery cell impedance at each of the frequencies within the set of frequencies.