Estimation device, energy storage module, estimation method, and computer program

Patent metadata

Field	Value
Publication number	US-12584969-B2
Application number	US-202218551505-A
Country	US
Kind code	B2
Filing date	Mar 9, 2022
Priority date	Mar 26, 2021
Publication date	Mar 24, 2026
Grant date	Mar 24, 2026

Abstract

An estimation device is a device that estimates a charge state of an energy storage device including a negative electrode having a negative active material that contains Si. The estimation device includes a control unit that determines based on a charge-discharge history of the energy storage device whether or not to perform a first estimation method of estimating a charge state of the energy storage device by using a relationship between the charge state and a voltage of the energy storage device.

First claim

The invention claimed is:

1 . An estimation device for estimating a charge state of an energy storage device that includes a negative electrode having a negative active material that contains Si, the estimation device comprising:
a control unit that is configured to determine based on a charge-discharge history of the energy storage device whether or not to perform a first estimation method of estimating the charge state of the energy storage device by using a relationship between the charge state and a voltage of the energy storage device, wherein the control unit is configured to determine whether or not to perform the first estimation method in accordance with a result of estimation relating to a transient potential change of the negative electrode.

2 . The estimation device according to claim 1 , wherein the control unit is configured to determine to perform the first estimation method in a case where the voltage of the energy storage device is within a range of a voltage threshold where the transient potential change of the negative electrode corresponding to a content of Si in the negative active material is not generated.

3 . The estimation device according to claim 1 , wherein the control unit is configured to determine to perform the first estimation method in a case where discharge that exceeds a deep discharge threshold corresponding to a content of Si in the negative active material is performed in the energy storage device.

4 . The estimation device according to claim 1 , wherein
a charge state-voltage profile indicating a relationship between a charge state and the voltage of the energy storage device includes: a first region where a shape of the charge state-voltage profile changes due to the transient potential change of the negative electrode and a second region where the shape of the charge state-voltage profile does not change, and the control unit is configured to estimate the charge state using the charge-state voltage profile in the second region.

5 . The estimation device according to claim 1 , wherein in a case where the control unit determines not to perform the first estimation method, the control unit is configured to perform a second estimation method for estimating the charge state of the energy storage device using an integrated value of a current flowing into the energy storage device and/or flowing out from the energy storage device.

6 . An energy storage module comprising:
an energy storage device; and the estimation device according to claim 1 .

7 . A method for estimating a charge state of an energy storage device that includes a negative electrode having a negative active material that contains Si, the method comprising:
determining based on a charge-discharge history of the energy storage device whether or not to perform a first estimation method of estimating the charge state of the energy storage device by using a relationship between the charge state and a voltage of the energy storage device; and determining whether or not to perform the first estimation method in accordance with a result of estimation relating to a transient potential change of the negative electrode.

8 . The method according to claim 7 , further comprising determining to perform the first estimation method in a case where the voltage of the energy storage device is within a range of a voltage threshold where the transient potential change of the negative electrode corresponding to a content of Si in the negative active material is not generated.

9 . The method according to claim 7 , further comprising determining to perform the first estimation method in a case where discharge that exceeds a deep discharge threshold corresponding to a content of Si in the negative active material is performed in the energy storage device.

10 . The method according to claim 7 , wherein a charge state-voltage profile indicating a relationship between a charge state and the voltage of the energy storage device includes: a first region where a shape of the charge state-voltage profile changes due to the transient potential change of the negative electrode and a second region where the shape of the charge state-voltage profile does not change, and
the method further comprises estimating the charge state using the charge-state voltage profile in the second region.

11 . The method according to claim 7 , wherein in a case where it is determined not to perform the first estimation method, the method comprises performing a second estimation method for estimating the charge state of the energy storage device using an integrated value of a current flowing into the energy storage device and/or flowing out from the energy storage device.

12 . A non-transitory computer-readable medium that stores a computer program for causing a computer that estimates a charge state of an energy storage device that includes a negative electrode having a negative active material that contains Si to perform processing when executed on a processor of:
determining based on a charge-discharge history of the energy storage device whether or not to perform a first estimation method of estimating the charge state of the energy storage device by using a relationship between the charge state and a voltage of the energy storage device; and determining whether or not to perform the first estimation method in accordance with a result of estimation relating to a transient potential change of the negative electrode.

13 . The non-transitory computer-readable medium according to claim 12 , further comprising determining to perform the first estimation method in a case where the voltage of the energy storage device is within a range of a voltage threshold where the transient potential change of the negative electrode corresponding to a content of Si in the negative active material is not generated.

14 . The non-transitory computer-readable medium according to claim 12 , further comprising determining to perform the first estimation method in a case where discharge that exceeds a deep discharge threshold corresponding to a content of Si in the negative active material is performed in the energy storage device.

15 . The non-transitory computer-readable medium according to claim 12 , wherein a charge state-voltage profile indicating a relationship between a charge state and the voltage of the energy storage device includes: a first region where a shape of the charge state-voltage profile changes due to the transient potential change of the negative electrode and a second region where the shape of the charge state-voltage profile does not change, and
the method further comprises estimating the charge state using the charge-state voltage profile in the second region.

16 . The non-transitory computer-readable medium according to claim 12 , wherein in a case where it is determined not to perform the first estimation method, the method comprises performing a second estimation method for estimating the charge state of the energy storage device using an integrated value of a current flowing into the energy storage device and/or flowing out from the energy storage device.

Assignees

• Gs Yuasa Int Ltd

Inventors

• Ichikawa Shinnosuke
• Miyazono Shinya
• Tanoi Akihito
• Nishikawa Heisuke
• Nakajima Nobuhiro
• Shimizu Takashi

Classifications

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H01M2004/027

  Negative electrodes · CPC title

• H01M10/48

  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 title

• H01M10/425

  Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing (printed circuits H05K1/00) · CPC title

• H01M4/483

  for non-aqueous cells (H01M4/485 takes precedence) · CPC title