Systems and methods for estimating state of health of an energy storage device

Patent metadata

Field	Value
Publication number	US-2021268932-A1
Application number	US-202117321767-A
Country	US
Kind code	A1
Filing date	May 17, 2021
Priority date	Feb 12, 2019
Publication date	Sep 2, 2021
Grant date	—

Abstract

A system for determining a state of health (SOH) of an energy storage device comprises a controller configured to be coupled to the energy storage device. The controller is configured to determine a current value drawn by or supplied to the energy storage device over a predefined period of time. In response to the current value not satisfying a current threshold, the controller determines a current gain factor and determines an adjusted current value from the determined current value based on the current gain factor. The controller is configured to determine an estimated SOH of the energy storage device based on the adjusted current value, and indicate the estimated SOH on a user interface.

First claim

What is claimed is:

1 . A system for determining a state of health (SOH) of an energy storage device, comprising:
a controller configured to be coupled to the energy storage device, the controller configured to:
determine a current value drawn from or supplied to the energy storage device over a predefined period of time;
in response to the current value not satisfying a current threshold, determine a current gain factor;
determine an adjusted current value from the determined current value based on the current gain factor;
determine an estimated SOH of the energy storage device based on the adjusted current value; and
indicate the estimated SOH of the energy storage device on a user interface.

2 . The system of claim 1 , wherein the controller is further configured to determine a cumulative adjusted current value from a plurality of the adjusted current values, and wherein the estimated SOH is determined based on the cumulative adjusted current value.

3 . The system of claim 1 , wherein the system is included in a vehicle having an engine, and wherein the controller is further configured to control a power distribution split between the energy storage device and the engine based on the estimated SOH.

4 . The system of claim 1 , wherein determining the estimated SOH comprises determining a difference between a total capacity of the energy storage device and a consumed capacity of the energy storage device, the consumed capacity based on a sum of adjusted current values drawn from the energy storage device over a predefined period of time.

5 . The system of claim 1 , wherein the current gain factor has a value greater than 1 when the determined current value is greater than the current threshold, and wherein the current gain factor has a value less than 1 when the determined current value is less than the current threshold.

6 . The system of claim 1 , wherein the controller is further configured to:
determine a temperature of the energy storage device; and in response to the temperature not satisfying a temperature threshold, determine a temperature gain factor; wherein determining the adjusted current value from the determined current value is also based on the temperature gain factor.

7 . The system of claim 6 , wherein the temperature gain factor has a value greater than 1 when the determined temperature value is greater than or less than the temperature threshold.

8 . The system of claim 1 , wherein the controller is further configured to:
determine a state of charge (SOC) of the energy storage device; and in response to the SOC not satisfying a SOC threshold, determine a SOC gain factor; wherein determining the adjusted current value from the determined current value is also based on the SOC gain factor.

9 . The system of claim 8 , wherein the SOC threshold comprises a range between approximately 10% SOC and 90% SOC of the energy storage device.

10 . The system of claim 8 , wherein the SOC gain factor has a value greater than 1 when the determined SOC value is greater than or less than the SOC threshold.

11 . A vehicle, comprising:
an energy storage device; and a controller configured to:
determine a current value drawn from or supplied to the energy storage device over a predefined period of time;
in response to the current value not satisfying a current threshold, determine a current gain factor;
determine an adjusted current value from the determined current value based on the current gain factor;
determine an estimated SOH of the energy storage device based on the adjusted current value; and
selectively drive the vehicle via a traction motor using power drawn from the energy storage device based on the estimated SOH of the energy storage device.

12 . The vehicle of claim 11 , wherein the controller is further configured to determine a cumulative adjusted current value from a plurality of the adjusted current values, and wherein the estimated SOH is determined based on the cumulative adjusted current value.

13 . The vehicle of claim 11 , wherein the determining the estimated SOH comprises determining a difference between a total capacity of the energy storage device and a consumed capacity of the energy storage device, the consumed capacity based on a sum of adjusted current values drawn from the energy storage device over a predefined time period.

14 . The vehicle of claim 11 , wherein the controller is further configured to:
determine a temperature of the energy storage device; and in response to the temperature not satisfying a temperature threshold, determine a temperature gain factor, wherein determining the adjusted current value from the determined current value is also based on the temperature gain factor.

15 . The vehicle of claim 11 , wherein the controller is further configured to:
measure a state of charge (SOC) of the energy storage device; and in response to the SOC not satisfying a SOC threshold, determine a SOC gain factor, wherein determining the adjusted current value from the determined current value is also based on the SOC gain factor.

16 . A method for determining a state of health (SOH) of an energy storage device, comprising:
determining a current value drawn from or supplied to the energy storage device over a period of time; in response to the current value not satisfying a current threshold, determining a current gain factor; determining an adjusted current value from the determined current value based on the current gain factor; determining an estimated SOH of the energy storage device based on the adjusted current value; and indicating the estimated SOH of the energy storage device on a user interface.

17 . The method of claim 16 , further comprising determining a cumulative adjusted current value from a plurality of the adjusted current values, and wherein the estimated SOH is determined based on the cumulative adjusted current value.

18 . The method of claim 16 , wherein the controller is further configured to control a power distribution split between the energy storage device and an engine of a vehicle based on the estimated SOH.

19 . The method of claim 18 , further comprising:
determining a temperature of the energy storage device; and in response to the temperature not satisfying a temperature threshold, determining a temperature gain factor, wherein determining the adjusted current value from the determined current value is also based on the temperature gain factor.

20 . The method of claim 18 , further comprising:
determining a state of charge (SOC) of the energy storage device; and in response to the SOC not satisfying a SOC threshold, determining a SOC gain factor, wherein determining the adjusted current value from the determined current value is also based on the SOC gain factor.

Assignees

• Cummins Inc

Inventors

• Zhang Ruigang
• Fan Guodong
• Booth Richard A

Classifications

• H02J7/977

  of the battery · CPC title

• H02J7/84

  Control of state of health [SOH] · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J2105/37

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

• H01M10/486

  for measuring temperature · CPC title