# US 12,591,014 B2 · Battery measurement method and apparatus for complex impedance measurement > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,591,014 B2 - Document ID: US12591014B2 - Status: Granted - Kind: B2 - Application number: 18/399,074 - Filed: 2023-12-28 - Published: 2024-04-25 - Granted: 2026-03-31 - Earliest claimed: 2021-06-30 - Assignees: Denso Corporation - Applicants: Denso Corporation - Inventors: Masaaki Kitagawa; Shun Miyauchi; Isao Ishibe - Web page: https://patentgrep.com/patent/US12591014B2 ## CPC - G01R 31/3835: involving only voltage measurements - G01R 27/02: Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant (by measuring phase angle only G01R25/00) - G01R 31/36: Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC] - G01R 31/3648: {comprising digital calculation means, e.g. for performing an algorithm} - G01R 31/389: Measuring internal impedance, internal conductance or related variables - G01R 31/392: Determining battery ageing or deterioration, e.g. state of health - H01M 10/4285: {Testing apparatus} - H01M 10/48: Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte (constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569) - H02J 7/00: Circuit arrangements for charging or discharging batteries or for supplying loads from batteries - H02J 7/80: including monitoring or indicating arrangements - Y02E 60/10: Energy storage using batteries - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - H02J: ELECTRIC POWER NETWORKS; CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract In a battery measurement apparatus, a current controller sets a predetermined wavenumber of each of first and second alternating signals, and determines whether an input or an output of the predetermined wavenumber of one of the first and second alternating signals to or from a rechargeable battery has completed. The current controller switches, in response to determination that the input or output of the predetermined wavenumber of one of the first and second alternating signals to or from the rechargeable battery has completed, the completed one of the first and second alternating signals to a new alternating signal having another frequency while continuing the input or output of the other of the first and second alternating signals to or from the rechargeable battery. ## Claims ### Claim 1 A battery measurement apparatus for measuring a state of a rechargeable battery, the battery measurement apparatus comprising: a processing circuitry configured to; perform one of: a first task of causing the rechargeable battery to output a composite wave signal that is combination of at least first and second alternating signals, the first and second alternating signals respectively having first and second frequencies different from one another; and a second task of causing the first and second alternating signals to be inputted to the rechargeable battery as the composite wave signal; a voltage measurement unit configured to measure a voltage variation across the rechargeable battery in response to the composite wave signal; wherein: the processing circuitry is further configured to: analyze, for each of the first and second frequencies, the voltage variation in accordance with the first and second alternating signals and the voltage variation to accordingly calculate information on a complex impedance of the rechargeable battery, set a predetermined wavenumber of each of the first and second alternating signals; determine whether an input or an output of the predetermined wavenumber of one of the first and second alternating signals to or from the rechargeable battery has completed; and switch, in response to determination that the input or output of the predetermined wavenumber of one of the first and second alternating signals to or from the rechargeable battery has completed, the completed one of the first and second alternating signals to a new alternating signal having another frequency while continuing the input or output of the other of the first and second alternating signals to or from the rechargeable battery. ### Claim 2 (depends on 1) The battery measurement apparatus according to claim 1, wherein the processing circuitry is further configured to: estimate a magnitude of the complex impedance for each of the first and second frequencies, obtain the estimated magnitude of the complex impedance for each of the first and second frequencies; and determine, based on the estimated magnitude of the complex impedance for each of the first and second frequencies, an amplitude of the corresponding one of the first and second alternating signals. ### Claim 3 (depends on 1) The battery measurement apparatus according to claim 1, wherein: the processing circuitry is further configured to set (i) an amplitude of each of the first and second alternating signals and (ii) an input timing or an output timing of the first and second alternating signals such that an amplitude of the composite wave signal is within a predetermined range. ### Claim 4 (depends on 1) The battery measurement apparatus according to claim 1, wherein: the first frequency of the first alternating signal is higher than the second frequency of the second alternating signal; and the processing circuitry is further configured to set an output period of the first alternating signal such that the output period of the first alternating signal matches a period of the second alternating signal during which instantaneous values of the second alternating signal are closer to an average of the second alternating signal than to a maximum or minimum of the second alternating signal. ### Claim 5 (depends on 1) The battery measurement apparatus according to claim 1, wherein: the processing circuitry is further configured to select the first and second frequencies of the first and second alternating signals while preventing one of the first and second frequencies from becoming an integral multiple of the other of the first and second frequencies. ### Claim 6 (depends on 1) The battery measurement apparatus according to claim 1, wherein: the rechargeable battery is electrically connected to at least one electrical load; and the processing circuitry is further configured to change the wavenumber of each of the first and second alternating signals during the at least one electrical load being activated to be larger than the wavenumber of a corresponding one of the first and second alternating signals during the at least one electrical load being deactivated. ### Claim 7 (depends on 1) The battery measurement apparatus according to claim 1, further comprising: at least first and second lock-in amplifiers provided for the first and second alternating signals that constitute the composite wave signal, wherein: the first and second lock-in amplifiers are configured to analyze the response signal simultaneously for the respective first and second frequencies to accordingly calculate the information on the complex impedance of the rechargeable battery. ### Claim 8 (depends on 1) The battery measurement apparatus according to claim 1, wherein the processing circuitry is implemented by one or more hardware electronic circuits. ### Claim 9 (depends on 1) The battery measurement apparatus according to claim 1, wherein the processing circuitry is implemented by one or more hardware-software hybrid circuits. ### Claim 10 (depends on 1) The battery measurement apparatus according to claim 1, wherein the processing circuitry comprises at least one processor executing program instructions stored in a storage. ### Claim 11 A battery measurement method to be carried out by a battery measurement apparatus for measuring a state of a rechargeable battery, the battery measurement method comprising: a performing step of performing one of: a first task of causing the rechargeable battery to output a composite wave signal that is combination of at least first and second alternating signals, the first and second alternating signals respectively having first and second frequencies different from one another; and a second task of causing the first and second alternating signals to be inputted to the rechargeable battery as the composite wave signal; a measuring step of measuring a voltage variation across the rechargeable battery in response to the composite wave signal; and a calculating step of analyzing, for each of the first and second frequencies, the voltage variation in accordance with the first and second alternating signals and the voltage variation to accordingly calculate information on a complex impedance of the rechargeable battery, wherein: the performing step further includes: setting a predetermined wavenumber of each of the first and second alternating signals; determining whether an input or an output of the predetermined wavenumber of one of the first and second alternating signals to or from the rechargeable battery has completed; switching, in response to determination that the input or output of the predetermined wavenumber of one of the first and second alternating signals to or from the rechargeable battery has completed, the completed one of the first and second alternating signals to a new alternating signal having another frequency while continuing the input or output of the other of the first and second alternating signals to or from the rechargeable battery.