# US 12,000,902 B2 · Multispectral impedance determination under dynamic load conditions > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,000,902 B2 - Document ID: US12000902B2 - Status: Granted - Kind: B2 - Application number: 17/608,205 - Filed: 2020-05-01 - Published: 2022-06-30 - Granted: 2024-06-04 - Earliest claimed: 2019-05-02 - Assignees: Dynexus Technology, Inc. - Applicants: Dynexus Technology, Inc. - Inventors: John Morrison - Web page: https://patentgrep.com/patent/US12000902B2 ## CPC - G01R 31/389: Measuring internal impedance, internal conductance or related variables - 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 31/3648: {comprising digital calculation means, e.g. for performing an algorithm} - G01R 31/386: {using test-loads} - 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 Impedance testing devices, circuits, systems, and related methods are disclosed. A Device Under Test (DUT) is excited with a multispectral excitation signal for an excitation time period while the DUT is under a load condition from a load operably coupled to the DUT. A response of the DUT is sampled over a sample time period. The sample time period is configured such that it includes an in-band interval during the excitation time period and one or more out-of-band intervals outside of the in-band interval. A response of the DUT to the load condition during the in-band interval is estimated by analyzing samples of the response from the one or more out-of-band intervals. Adjusted samples are computed by subtracting the estimated load response during the in-band interval from the samples from the in-band interval. An impedance of the DUT is estimated by analyzing the adjusted samples. ## Claims ### Claim 1 A method of measuring impedance using an impedance measurement device, comprising: exciting a device under a load condition with a multispectral excitation signal having an excitation time period; sampling a response of said device over a sample time period including an in-band interval during said excitation time period disposed between out-of-band intervals outside of the in-band interval; estimating a load response of said device to said load condition during said in-band interval by analyzing said response included in said out-of-band intervals using a sum of sines analysis using a fundamental frequency including a period having a duration greater than said response including said in-band and said out-of-band intervals; subtracting said load response during said in-band interval from said response during said in-band interval; analyzing said response having said load response subtracted from said response using a sum of sines analysis; and generating an impedance measurement of said device. ### Claim 2 (depends on 1) The method of claim 1, wherein said device comprises a battery. ### Claim 3 (depends on 2) The method of claim 2, wherein sampling said response of said battery comprises sampling said response of said battery under a charging load condition. ### Claim 4 (depends on 2) The method of claim 2, wherein sampling said response of said battery comprises sampling said response of said battery under a discharging load condition. ### Claim 5 (depends on 1) The method of claim 1, wherein exciting said device comprises applying a current signal, and wherein sampling said response of said device comprises sampling a voltage response. ### Claim 6 (depends on 1) The method of claim 1, wherein exciting said device comprises applying a voltage signal, and wherein sampling said response of said device comprises sampling a current response. ### Claim 7 (depends on 1) The method of claim 1, wherein said out-of-band intervals comprise a pre-band interval immediately before said excitation time period, and a post-band interval immediately after the excitation time period. ### Claim 8 (depends on 1) The method of claim 1, wherein said excitation time period includes two excitation time periods and said out-of-band intervals further includes an interval between said two excitation time periods. ### Claim 9 (depends on 1) The method of claim 1, wherein estimating the load response comprises: fitting said sum of sines analysis to samples of said response from said out-of-band intervals using said fundamental frequency including a period having a duration greater than said response including said in-band and said out-of-band intervals. ### Claim 10 (depends on 9) The method of claim 9, further comprising adjusting fundamental frequency to correct fit of said sum of sines analysis to said samples from said out-of-band intervals. ### Claim 11 (depends on 10) The method of claim 10, wherein adjusting said fundamental frequency comprises decreasing said fundamental frequency to correct said fit of said sum of sines analysis to said samples from said out-of-band intervals. ### Claim 12 (depends on 11) The method of claim 11, wherein decreasing said fundamental frequency to correct said fit comprises a multiple of a duration of said out-of-band interval immediately before said excitation time period, said multiple of said duration occurring in a range of about 4 times and about 1000 times. ### Claim 13 (depends on 11) The method of claim 11, further comprising using said fit corrected by adjustment of said fundamental frequency for analyzing said sum of sines analysis at time points corresponding to said samples from said in-band interval. ### Claim 14 (depends on 9) The method of claim 9, further comprising including one or more integer harmonic frequencies of said fundamental frequency. ### Claim 15 (depends on 14) The method of claim 14, wherein said one or more integer harmonic frequencies occurs in range of between about 1 and about 100 integer harmonic frequencies. ### Claim 16 (depends on 14) The method of claim 14, further comprising using said fit corrected by including said one or more integer harmonic frequencies for analyzing said sum of sines analysis at time points corresponding to said samples from said in-band interval. ### Claim 17 (depends on 9) The method of claim 9, wherein said fitting comprises: discarding said in-band interval; and using time cross talk compensation analysis to fit said response time record during said in-band interval and out-of-band intervals. ### Claim 18 (depends on 17) The method of claim 17, wherein said estimating said impedance of said device comprises analyzing said response using an impedance spectrum algorithm. ### Claim 19 (depends on 18) The method of claim 18, wherein said impedance spectrum algorithm includes one or more of TCTC, HOST, HSCD, FST, and GFST.