Lithium ion battery control device, and lithium ion battery control method

Patent metadata

Field	Value
Publication number	US-11309720-B2
Application number	US-201916569695-A
Country	US
Kind code	B2
Filing date	Sep 13, 2019
Priority date	Sep 26, 2018
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

A lithium ion battery control device includes an acquirer configured to acquire a determination index related to the degree of occlusion of a lithium ion battery in which a degree of occlusion of lithium ions occluded in graphite of a negative electrode changes in accordance with an amount of stored power, and a controller configured to perform control for causing the lithium ion battery to be charged with power or causing power of the lithium ion battery to be discharged so that the degree of occlusion is close to a degree of occlusion associated with a specific region when a region associated with the degree of occlusion is determined not to be the specific region associated with the degree of occlusion which includes LiC 12 having a degree of occlusion represented by a stoichiometric ratio and does not include LiC 6 having a degree of occlusion represented by a stoichiometric ratio.

First claim

What is claimed is:

1. A lithium ion battery control device for controlling charging or discharging of a lithium ion battery in which a degree of occlusion of lithium ions occluded in graphite of a negative electrode changes in accordance with an amount of stored power, the lithium ion battery control device comprising:
an acquirer configured to acquire a determination index related to the degree of occlusion; and
a controller configured to control charging the lithium ion battery with power or control discharging power from the lithium ion battery, so that the degree of occlusion is close to a degree of occlusion associated with a specific region when a region associated with the degree of occlusion is determined not to be the specific region, which includes LiC 12 having a degree of occlusion represented by a first stoichiometric ratio value and does not include LiC 6 having a degree of occlusion represented by a second stoichiometric ratio value on the basis of the determination index acquired by the acquirer,
wherein the controller is configured to control the charging or the discharging, so that the degree of occlusion is close to the degree of occlusion associated with the specific region when the region associated with the degree of occlusion is determined to be: a first specific region including LiC 6 having a degree of occlusion represented by the second stoichiometric ratio value, a second specific region including LiC 18 having a degree of occlusion represented by a third stoichiometric ratio value, or a third specific region including a structure of a degree of occlusion greater than or equal to that of LiC 27 having a degree of occlusion represented by a fourth stoichiometric ratio value,
wherein a deterioration rate of the lithium ion battery decreases in an order of the first specific region, the second specific region, and the third specific region, and the specific region, and
wherein the controller is configured to control the charging or the discharging, so that the degree of occlusion is close to the degree of occlusion associated with a region having a lower deterioration rate than the region associated with the degree of occlusion.

2. The lithium ion battery control device according to claim 1 , wherein the specific region is a region where LiC 12 is dominant.

3. The lithium ion battery control device according to claim 2 , wherein the the second specific region does not include LiC 27 having a degree of occlusion represented by the fourth stoichiometric ratio value.

4. The lithium ion battery control device according to claim 1 , wherein the controller is configured to control the discharging so that the degree of occlusion is close to the degree of occlusion associated with the third specific region, and wherein the charging or the discharging so that the degree of occlusion is close to the degree of occlusion associated with the specific region is determined not to be performed if the region associated with the degree of occlusion is determined to be the second specific region.

5. The lithium ion battery control device according to claim 1 , wherein the controller is configured to control the charging so that the degree of occlusion is close to the degree of occlusion associated with the specific region when the lithium ion battery is charged by an external system.

6. The lithium ion battery control device according to claim 1 , wherein the controller is configured to stop the charging before an amount of charge exceeds an amount of charge associated with the specific region when the lithium ion battery is charged by an external system.

7. The lithium ion battery control device according to claim 1 , wherein the controller is configured to control the charging or the discharging, so that the degree of occlusion is close to the degree of occlusion associated with the specific region or the degree of occlusion is close to a degree of occlusion associated with the region having the lower deterioration rate than the region associated with the degree of occlusion when the region associated with the degree of occlusion is determined to be different from the specific region if supply of power from the lithium ion battery is in a pause state.

8. The lithium ion battery control device according to claim 1 , wherein the controller is configured to control the charging or the discharging, so that the degree of occlusion is close to the degree of occlusion associated with the specific region or the degree of occlusion is close to a degree of occlusion associated with the region having the lower deterioration rate than the region associated with the degree of occlusion when the region associated with the degree of occlusion is determined to be different from the specific region in an operation state in which the lithium ion battery is supplying power as compared with when the region associated with the degree of occlusion is determined to be the specific region.

9. The lithium ion battery control device according to claim 1 , further comprising a generator configured to generate a model for determining the region associated with the degree of occlusion on the basis of information acquired through the charging or discharging, wherein the charging is a constant-current charging at less than or equal to a prescribed charging rate, and wherein the discharging is a constant-current discharging at less than or equal to a prescribed discharging rate.

10. The lithium ion battery control device according to claim 1 , further comprising a generator configured to estimate a relationship between a capacity and a voltage using voltage data in a prescribed current range in the lithium ion battery and generate a model for determining the region associated with the degree of occlusion using an estimation result.

11. A lithium ion battery control device for controlling charging or discharging of a lithium ion battery in which a degree of occlusion of lithium ions occluded in graphite of a negative electrode changes in accordance with an amount of stored power, the lithium ion battery control device comprising:
an acquirer configured to acquire a determination index related to the degree of occlusion; and
a controller configured to control charging the lithium ion battery with power or control discharging power from the lithium ion battery, so that the degree of occlusion is close to a degree of occlusion associated with a specific region when a region associated with the degree of occlusion is determined not to be the specific region, which includes LiC 12 having a degree of occlusion represented by a first stoichiometric ratio value and does not include LiC 6 having a degree of occlusion represented by a second stoichiometric ratio value on the basis of the determination index acquired by the acquirer,
wherein the determination index is an index according to a capacity of the lithium ion battery, an SOC, a cell open circuit voltage of the lithium ion battery, an index according to a first correlation between the SOC and the cell open circuit voltage, or an index according to a second correlation between a capacity and a voltage, and
wherein the controller is configured to further identify a region associated with the degree of occlusion of the lithium ion battery using a degree of deterioration of the lithium ion battery.

12. The lithium ion battery control device according to claim 11 , wherein the controller is configured to correct the determination index using a preset correction coefficient according to the degree of deterioration of the lithium ion battery and identify the region associated with the degree of occlusion on the basis of a determination index after the correction.

Assignees

• Honda Motor Co Ltd

Inventors

• Ito Yuki
• Tamai Atsushi
• Sato Kenji
• Nakao Kazuhito
• Abe Hajime

Classifications

• H02J2105/37

  exchanging power with electric vehicles [EV] or with hybrid electric vehicles [HEV] · CPC title

• H02J7/84

  Control of state of health [SOH] · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/971

  the charge cycle being controlled or terminated in response to non-electric parameters · CPC title

• H01M10/0525 Primary

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title