Patent ID: 8615372
Filing Date: 2013-12-24
Classification: G01R,G16Z,H01M,Y02E

Abstract:
1. A state estimating device for a secondary battery ( 10 ), comprising: a detecting unit for detecting a battery voltage, a battery current and a battery temperature of said secondary battery; a battery state estimating unit configured to successively estimate, based on a detected value of said battery temperature and a detected value of a first state quantity which is one of said battery voltage and said battery current, a charging rate of said secondary battery, an open-circuit voltage of said secondary battery and a second state quantity which is the other of said battery voltage and said battery current, in accordance with a battery model equation; and a parameter estimating unit configured to calculate an estimation error indicating a difference between a detected value and an estimated value of said second state quantity, based on the detected value and the estimated value of said second state quantity, and to estimate a predetermined parameter changing in accordance with a change in a state of said secondary battery, of a parameter group used for said battery model equation, based on said estimation error and one of said charging rate and said open-circuit voltage, wherein said battery state estimating unit corrects a positive electrode open-circuit potential and a negative electrode open-circuit potential by reflecting an estimation result of said predetermined parameter estimated by said parameter estimating unit in said battery model equation, and estimates said open-circuit voltage based on the corrected positive electrode open-circuit potential and the corrected negative electrode open-circuit potential.