Patent ID: 7009402

Claim:
An estimating apparatus for a secondary cell, comprising: a current detecting section that detects a current (I) charged into and discharged from the secondary cell; a voltage detecting section that detects a terminal voltage (V) across the secondary cell; a parameter estimating section that integrally estimates all parameters (θ) at one time in at least one of the following equations (1) and (2) with the measured current (I) and terminal voltage (V) inputted into an adaptive digital filter using a cell model described in a corresponding one of the following equations (1) and (2) whose parameters are estimated; an open-circuit voltage calculating section that calculates an open-circuit voltage (Vo) using the current (I), the terminal voltage (V), and the parameter estimated values (θ); an input enabling power estimating section that estimates an input enabling power (P in ) of the secondary cell on the basis of the parameter estimated values (θ) and open-circuit voltage (Vo); and an output enabling power estimating section that estimates an output enabling power (P out ) of the secondary cell on the basis of the parameter estimated values and the open-circuit voltage (Vo), the equation (1) being V = B ⁡ ( s ) A ⁡ ( s ) · I + 1 C ⁡ ( s ) · Vo , wherein ⁢ ⁢ A ⁡ ( s ) = ∑ k = 0 n ⁢ ⁢ a k · s k , B ⁡ ( s ) = ∑ k = 0 n ⁢ ⁢ b k · s k , C ⁡ ( s ) = ∑ k = 0 n ⁢ ⁢ c k · s k , ( 1 ) s denotes a Laplace transform operator, A(s), B(s), and C(s) denote each poly-nominal of s (n denotes degrees), a 1 ≠0, b 1 ≠0, and c 1 ≠0 and the equation (2) being V = B ⁡ ( s ) A ⁡ ( s ) · I + 1 A ⁡ ( s ) · Vo , wherein ⁢ ⁢ A ⁡ ( s ) = ∑ k = 0 n ⁢ ⁢ a k · s k ⁢ ⁢ and ⁢ ⁢ B ⁡ ( s ) = ∑ k = 0 n ⁢ ⁢ b k · s k . ( 2 )