STATE ESTIMATING DEVICE FOR SECONDARY BATTERY
First Claim
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 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, whereinsaid 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.
1 Assignment
0 Petitions
Accused Products
Abstract
A battery state estimating unit estimates an internal state of a secondary battery in accordance with a battery model equation in every arithmetic cycle, and estimates a charging rate and a battery current based on a result of the estimation. A parameter estimating unit obtains a battery current measured by a sensor as well as the charging rate and the battery current estimated by the battery state estimating unit. The parameter estimating unit estimates a capacity deterioration parameter such that a rate of change in difference (estimation error) between a summed value of an actual current and a summed value of an estimated current with respect to the charging rate is minimized. A result obtained by estimating the capacity deterioration parameter is reflected in the battery model by the battery state estimating unit.
-
Citations
23 Claims
-
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 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. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23)
-
Specification