STATE ESTIMATING DEVICE OF SECONDARY BATTERY

• Main Authors: AMANO, Yasushi, TOMURA, Shuji, TAKEMOTO, Takeshi, HAGA, Nobuyasu, FUCHIMOTO, Tetsuya, UMENO, Takaji, NISHI, Yuji
• Format: Patent
• Language: English; French; German
• Published: 13.03.2019
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY; TESTING

A battery state estimating unit estimates an internal state of a secondary battery according to a battery model equation in every arithmetic cycle, and calculates an SOC based on a result of the estimation. A parameter characteristic map stores a characteristic map based on a result of actual measurement performed in an initial state (in a new state) on a parameter diffusion coefficient and a DC resistance in the battery model equation. The parameter change rate estimating unit estimates a DC resistance change rate represented by a ratio of a present DC resistance with respect to a new-state parameter value by parameter identification based on the battery model equation, using battery data measured by sensors as well as the new-state parameter value of the DC resistance corresponding to the present battery state and read from the parameter characteristic map.