| 摘要 |
PROBLEM TO BE SOLVED: To provide a charge state estimation device and a charge state estimation method for a secondary battery which estimate an SOC value more accurately for variations in SOC-OCV characteristics due to charging and discharging and reduce an estimation error of the SOC.SOLUTION: The charge state estimation device comprises: a plurality of SOC-OCV characteristics tables 4-1 each containing a full charge characteristic curve, a complete discharge characteristic curve, and at least one SOC-OCV characteristic curve dividing a region between the full charge characteristic curve and the complete discharge characteristic curve, each of the SOC-OCV characteristic curves being given a travel value; a travel amount calculation part 4-2 calculating, based on a current integration amount by charging and discharging and a travel value of the SOC-OCV characteristic curve used immediately before the charging and discharging, a travel amount of the SOC-OCV characteristic curve according to the current integration amount; an SOC-OCV characteristics selection part 4-3 determining a travel value closest to the travel amount and selecting an SOC-OCV characteristic curve of the travel value; and an SOC estimation part 4-5 estimating an SOC value from a measured OCV value by using the selected SOC-OCV characteristic curve. |
