# US 2024/0201269 A1 · Capacity and state-of-charge estimation for a multi-battery energy storage system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0201269 A1 - Document ID: US20240201269A1 - Status: Published application - Kind: A1 - Application number: 18/541,220 - Filed: 2023-12-15 - Published: 2024-06-20 - Earliest claimed: 2022-12-20 - Assignees: Volvo Truck Corporation - Applicants: Volvo Truck Corporation - Inventors: Faisal ALTAF - Web page: https://patentgrep.com/patent/US20240201269A1 ## CPC - G01R 31/3842: combining voltage and current measurements - G01R 31/396: Acquisition or processing of data for testing or for monitoring individual cells or groups of cells within a battery - B60L 3/12: Recording operating variables {; Monitoring of operating variables} - B60L 58/18: of two or more battery modules - G01R 31/367: Software therefor, e.g. for battery testing using modelling or look-up tables - G01R 31/3835: involving only voltage measurements - H01M 50/249: specially adapted for aircraft or vehicles, e.g. cars or trains (constructional details of batteries specially adapted for electric vehicles B60L50/64) - H01M 50/512: Connection only in parallel - B60L 2240/547: Voltage - B60L 2240/549: Current - G01R 31/3828: using current integration - H01M 2220/20: Batteries in motive systems, e.g. vehicle, ship, plane - G01R: MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES (indicating correct tuning of resonant circuits H03J3/12) - B60L: PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES (arrangements or mounting of electrical propulsion units or of plural diverse prime-movers for mutual or common propulsion in vehicles B60K1/00, B60K6/20; arrangements or mounting of electrical gearing in vehicles B60K17/12, B60K17/14; preventing wheel slip by reducing power in rail vehicles B61C15/08; dynamo-electric machines H02K; control or regulation of electric motors H02P); SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES (electric coupling devices combined with mechanical couplings of vehicles B60D1/64; electric heating for vehicles B60H1/00); ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL (control or regulation of electric motors H02P); MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY ## Abstract A method of computing a state of charge of an energy storage system, ESS, with multiple parallel battery packs is provided. The method includes for each battery pack, predicting a time-evolved terminal voltage and current based on a respective measured terminal voltage; based on the predicted time-evolved terminal voltages and currents, computing a chargeable and/or dischargeable capacity of the ESS; and computing the state of charge of the ESS based on the chargeable and/or dischargeable capacity of the ESS. The method may seek to provide an accurate computation of SoC for an ESS with multiple parallel battery packs such that the full capability of the ESS is utilized. ## Claims ### Claim 1 A method of computing a state of charge of an energy storage system, ESS, with multiple parallel battery packs, the method comprising: for each battery pack, predicting a time-evolved terminal voltage and current based on a respective measured terminal voltage; based on the predicted time-evolved terminal voltages and currents, computing a chargeable and/or dischargeable capacity of the ESS; and computing the state of charge of the ESS based on the chargeable and/or dischargeable capacity of the ESS. ### Claim 2 (depends on 1) The method of claim 1, wherein the chargeable and/or dischargeable capacity of the ESS is computed using a Coulomb-counting approach. ### Claim 3 (depends on 1) The method of claim 1, wherein the chargeable capacity of the ESS is computed under an assumption of minimum charge time. ### Claim 4 (depends on 3) The method of claim 3, wherein the minimum charge time is calculated by: calculating an expected charge time for each battery pack based on its time-evolved terminal voltage; and selecting, from the expected charge times for all battery packs, the smallest expected charge time as said minimum charge time. ### Claim 5 (depends on 4) The method of claim 4, wherein the expected charge time is calculated by applying to the time-evolved terminal voltage a termination criterion including a charging limit voltage and an equilibrium condition. ### Claim 6 (depends on 1) The method of claim 1, wherein the dischargeable capacity of the ESS is computed under an assumption of minimum discharge time. ### Claim 7 (depends on 6) The method of claim 6, wherein the minimum discharge time is calculated by: calculating an expected discharge time for each battery pack based on its time-evolved terminal voltage; and selecting, from the expected discharge times for all battery packs, the smallest expected discharge time as said minimum charge time. ### Claim 8 (depends on 7) The method of claim 7, wherein the expected discharge time is calculated by applying to the time-evolved terminal voltage a termination criterion including a discharging limit voltage and an equilibrium condition. ### Claim 9 (depends on 1) The method of claim 1, wherein the time-evolved terminal voltages are predicted using a dynamic model of currents and voltages in a multi-battery system. ### Claim 10 (depends on 9) The method of claim 9, wherein the model is variable with respect to battery temperature and/or a setpoint charge/discharge-current profile. ### Claim 11 (depends on 1) The method of claim 1, wherein the current for each battery pack is predicted using current split prediction based on a total reference ESS current and a measured terminal voltage for the battery pack. ### Claim 12 (depends on 1) The method of claim 1, wherein the ESS is a vehicular ESS. ### Claim 13 (depends on 1) A processor device for computing a state of charge of an energy storage system, ESS, with multiple parallel battery packs, the device comprising: an interface for receiving sensor signals associated with the ESS; and processing circuitry configured to perform the method of claim 1. ### Claim 14 (depends on 1) A computer program product comprising program code for performing, when executed by a processor device performs the method of claim 1 ### Claim 15 (depends on 1) A non-transitory computer-readable storage medium comprising instructions which, when executed by the processor device cause the processor device to perform the method of claim 1.