Deterioration state detection apparatus and deterioration state detection method for energy storage device, and energy storage system

• US 10,295,609 B2
• Filed: 06/18/2014
• Issued: 05/21/2019
• Est. Priority Date: 07/23/2013
• Status: Active Grant

• Current Assignee: GS Yuasa International Ltd. (GS Yuasa Corporation)
• Original Assignee: GS Yuasa International Ltd. (GS Yuasa Corporation)
• Inventors: Ikeda, Yuichi, Tao, Yohei, Yamate, Shigeki
• Primary Examiner(s): Koval, Melissa J
• Assistant Examiner(s): Maini, Rahul
• Application Number:
  US14/905,137
• Publication Number:
  US 20160195588A1
• Time in Patent Office: 1,798 Days
• Field of Search: 324430
• CPC Class Codes: G01R 31/36 Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
• CPC Class Codes: G01R 31/3648 comprising digital calculation means, e.g. for performing an algorithm
• CPC Class Codes: G01R 31/389 Measuring internal impedance, internal conductance or related variables
• CPC Class Codes: G01R 31/392 Determining battery ageing or deterioration, e.g. state of health
• CPC Class Codes: G01R 31/44 Testing lamps
• CPC Class Codes: H01M 10/4257 Smart batteries, e.g. electronic circuits inside the housing of the cells or batteries
• 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 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 2010/4278 Systems for data transfer from batteries, e.g. transfer of battery parameters to a controller, data transferred between battery controller and main controller
• CPC Class Codes: H01M 2220/30 Batteries in portable systems, e.g. mobile phone, laptop
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/007 Regulation of charging or discharging current or voltage
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A deterioration state detection apparatus for detecting a deterioration state of capacity enabling charge or discharge of a nonaqueous electrolyte secondary battery includes: an acquisition unit that acquires a capacitance of the nonaqueous electrolyte secondary battery: and a determination unit that determines the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery, from change of the acquired capacitance.

Claims

1. A deterioration state detection apparatus for detecting a state before performance degradation, which is a state right before a rapid performance degradation of a nonaqueous electrolyte secondary battery, comprising:

an acquisition unit that acquires a capacitance of the nonaqueous electrolyte secondary battery; and

a determination unit that determines whether or not the nonaqueous electrolyte secondary battery is in the state before performance degradation as a deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery, from change of the acquired capacitance,

wherein the determination unit limits a charging upper limit voltage of the nonaqueous electrolyte secondary battery or an energizing maximum current to the nonaqueous electrolyte secondary battery based on a determination result of the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery.

2. The deterioration state detection apparatus according to claim 1,

wherein the determination unit determines whether or not a determination capacitance which is a capacitance calculated at a predetermined determination time point is smaller than a reference value, so that the determination unit determines the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery at the determination time point.

3. The deterioration state detection apparatus according to claim 2,

wherein the determination unit employs a value obtained by multiplying a capacitance average value being an average value of capacitances calculated before the determination time point by a predetermined constant, as the reference value, and determines whether or not the determination capacitance is smaller than the reference value, so that the determination unit determines the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery at the determination time point.

4. The deterioration state detection apparatus according to claim 3,

wherein the determination unit employs a value between 0.8 and 0.9 as the constant, and determines whether or not the determination capacitance is smaller than the reference value, so that the determination unit determines the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery at the determination time point.

5. The deterioration state detection apparatus according to claim 3,

wherein the acquisition unit acquires capacitances of the nonaqueous electrolyte secondary battery at a plurality of time points up to the determination time point, and the determination unit averages the plurality of capacitances acquired before the determination time point to calculate the capacitance average value, so that the determination unit determines the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery at the determination time point.

6. The deterioration state detection apparatus according to claim 1,

wherein the acquisition unit calculates the capacitance based on measurement using a complex impedance method, to acquire the capacitance.

7. The deterioration state detection apparatus according to claim 6,

wherein when a frequency at a point, where an imaginary axis component of an arc appearing when drawing a Nyquist diagram based on the measurement using the complex impedance method is a maximum value, is defined as a top frequency, the acquisition unit acquires the capacitance in a case where the top frequency is a predetermined threshold value or less.

8. The deterioration state detection apparatus according to claim 7, wherein the acquisition unit does not acquire the capacitance in a case where the top frequency is larger than the predetermined threshold value.

9. The deterioration state detection apparatus according to claim 7, wherein the determination unit determines the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery without including the capacitance acquired in a case where the top frequency is larger than the predetermined threshold value.

10. The deterioration state detection apparatus according to claim 1,

wherein the capacitance, an impedance R, and a top frequency f satisfy a relational expression of capacitance C=1/(2π

fR),

the impedance R is equivalent to the width of the real axis impedance in an arc represented in a Nyquist diagram based on a data row formed by combining a frequency, a real axis impedance, and an imaginary axis impedance, the data row being acquired by measurement using the complex impedance method,

the top frequency f is equivalent to a frequency at a point where an imaginary axis impedance is a maximum value in the arc.

11. An energy storage system comprising:

a nonaqueous electrolyte secondary battery; and

a deterioration state detection apparatus according to claim 1, wherein the deterioration state detection apparatus detects the state before performance degradation, which is the state right before a rapid performance degradation of the nonaqueous electrolyte secondary battery.

12. A deterioration state detection method for detecting, by using a computer, a state before performance degradation, which is a state right before a rapid performance degradation of a nonaqueous electrolyte secondary battery, comprising:

an acquiring step of acquiring a capacitance of the nonaqueous electrolyte secondary battery;

a determining step of determining whether or not the nonaqueous electrolyte secondary battery is in the state before performance degradation as a deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery, from change of the acquired capacitance; and

a limiting step of limiting a charging upper limit voltage of the nonaqueous electrolyte secondary battery or an energizing maximum current to the nonaqueous electrolyte secondary battery based on a determination result of the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery.

13. An integrated circuit for detecting a state before performance degradation, which is a state right before a rapid performance degradation of a nonaqueous electrolyte secondary battery, comprising:

an acquisition unit that acquires a capacitance of the nonaqueous electrolyte secondary battery; and

a determination unit that determines whether or not the nonaqueous electrolyte secondary battery is in the state before performance degradation as a deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery, from change of the acquired capacitance,

wherein the determination unit limits a charging upper limit voltage of the nonaqueous electrolyte secondary battery or an energizing maximum current to the nonaqueous electrolyte secondary battery based on a determination result of the deterioration state of capacity enabling charge or discharge of the nonaqueous electrolyte secondary battery.