Battery's state of charge estimation apparatus

• US 10,641,830 B2
• Filed: 04/01/2013
• Issued: 05/05/2020
• Est. Priority Date: 05/11/2012
• Status: Active Grant

• Current Assignee: Calsonic Kansei Corporation, KEIO University
• Original Assignee: Calsonic Kansei Corporation
• Inventors: Baba, Atsushi, Adachi, Shuichi
• Primary Examiner(s): Toatley, Jr., Gregory J
• Assistant Examiner(s): Stifter, Jr., Terence E
• Application Number:
  US14/400,160
• Publication Number:
  US 20150127280A1
• Time in Patent Office: 2,591 Days
• Field of Search: 702 63
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/367 Software therefor, e.g. for battery testing using modelling or look-up tables
• CPC Class Codes: G01R 31/382 Arrangements for monitoring battery or accumulator variables, e.g. SoC
• CPC Class Codes: G01R 31/3842 combining voltage and current measurements
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 2220/20 Batteries in motive systems, e.g. vehicle, ship, plane
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A battery'"'"'s state of charge estimation apparatus will be provided.

The battery'"'"'s state of charge estimation apparatus includes: a charge and discharge current detection unit; a terminal voltage detection unit; an open circuit voltage method state of charge estimation unit for estimating an open circuit voltage of the battery and an open circuit voltage method state of charge; a current integration method state of charge estimation unit for obtaining a current integration method state of charge as a state variable; and an error correction value calculation unit for calculating an error correction value for correcting the current integration method state of charge. The current integration method state of charge estimation unit corrects the current integration method state of charge by using the error correction value.

Claims

1. A battery'"'"'s state of charge estimation apparatus comprising:

a charge and discharge current detection unit for detecting a charge current and a discharge current of a battery;

a terminal voltage detection unit for detecting a terminal voltage of the battery;

a first processing unit for providing an open circuit voltage method state of charge estimate, the first processing unit configured to estimate an open circuit voltage of the battery based on the charge current and the discharge current detected by the charge and discharge current detection unit and the terminal voltage detected by the terminal voltage detection unit, and configured to estimate, based on the open circuit voltage, the open circuit voltage method state of charge from an open circuit voltage-state of charge characteristic of the battery;

a second processing unit for providing a current integration method state of charge, the second processing unit configured to use as a current integration model, a discrete state space model of a spreading system that uses a state variable of the spreading system in consideration of a current fluctuation Δ

i expressed by the following equation;

2. The battery'"'"'s state of charge estimation apparatus according to claim 1, wherein the third processing unit has Kalman filter and is configured to obtain the error correction value by multiplying a difference between the current integration method state of charge and the open circuit voltage method state of charge by Kalman gain.