Method and apparatus for estimating charging time of battery

Patent metadata

Field	Value
Publication number	US-2023045708-A1
Application number	US-202217869635-A
Country	US
Kind code	A1
Filing date	Jul 20, 2022
Priority date	Aug 5, 2021
Publication date	Feb 9, 2023
Grant date	—

Abstract

A method of estimating a charging time of a battery, includes: estimating an SOC of the battery by measuring at least one parameter of the battery; estimating an internal resistance of the battery based on the at least one parameter of the battery, the SOC of the battery, and SOC-OCV data; estimating a time length of a constant current (CC) charging section based on the SOC, the internal resistance, and the at least one parameter of the battery; and estimating a time length of a constant voltage (CV) charging section based on the SOC, the internal resistance, and the at least one parameter of the battery. The estimating of the time length of the CV charging section includes: estimating a charging current of the battery in a unit of an SOC step; and calculating the time length of the CV charging section in the unit of the SOC step.

First claim

What is claimed is:

1 . A method of estimating a charging time of a battery, the method comprising:
estimating a state-of-charge (SOC) of the battery by measuring at least one parameter of the battery; estimating an internal resistance of the battery based on the at least one parameter of the battery, the SOC of the battery, and SOC-open circuit voltage (OCV) data; estimating a time length of a constant current charging section based on the SOC, the internal resistance, and the at least one parameter of the battery; and estimating a time length of a constant voltage charging section based on the SOC, the internal resistance, and the at least one parameter of the battery, wherein the estimating of the time length of the constant voltage charging section comprises:
estimating a charging current of the battery in a unit of an SOC step based on the SOC, the internal resistance, and the at least one parameter of the battery; and
calculating the time length of the constant voltage charging section in the unit of the SOC step based on the SOC, the at least one parameter, and the charging current of the battery.

2 . The method of claim 1 , wherein the at least one parameter comprises a voltage, a current, and a temperature of the battery.

3 . The method of claim 1 , wherein the estimating of the internal resistance of the battery comprises:
calculating a first internal resistance of the battery with respect to the SOC of the battery based on SOC-internal resistance data of the battery; estimating a second internal resistance of the battery by calculating an OCV of the battery by using the SOC-OCV data, based on the SOC of the battery, and a difference between the OCV and a voltage of the battery; and calculating a third internal resistance of the battery with respect to a plurality of SOC grid points based on the first internal resistance and the second internal resistance.

4 . The method of claim 3 , wherein the estimating of the second internal resistance comprises:
calculating the OCV of the battery by using the SOC-OCV data, based on the SOC of the battery; estimating an estimated internal resistance of the battery based on a difference between the OCV and the voltage of the battery; deriving a linear regression equation based on the estimated internal resistance as a Y value and the SOC as an X value with respect to the estimated internal resistance and the SOC of the battery; and calculating the second internal resistance of the battery with respect to the plurality of SOC grid points, based on the linear regression equation.

5 . The method of claim 3 , wherein the plurality of SOC grid points indicate, based on the SOC of the battery on a horizontal axis and the internal resistance of the battery on a vertical axis, points for estimating the internal resistance of the battery with respect to an SOC of the horizontal axis.

6 . The method of claim 3 , wherein the calculating of the third internal resistance comprises:
calculating an internal resistance update value by multiplying a difference between the first internal resistance and the second internal resistance by a coefficient; and calculating the third internal resistance by adding the first internal resistance and the internal resistance update value.

7 . The method of claim 1 , wherein the SOC step represents a reference value dividing the constant current charging section and the constant voltage charging section, by an SOC unit, between a start SOC of the battery at a time point at which charging of the battery starts and an end SOC at a time point at which the charging is completed.

8 . Non-transitory computer readable media containing program instructions that, when executed by a computing device, cause the computing device to perform the method of claim 1 .

9 . An apparatus for estimating a charging time of a battery, the apparatus comprising:
memory storing data generated by measuring at least one parameter of the battery being charged; and at least one processor configured to:
estimate a state-of-charge (SOC) of the battery based on at least one parameter of the battery;
estimate an internal resistance of the battery based on the at least one parameter of the battery, the SOC of the battery, and SOC-open circuit voltage (OCV) data;
estimate a time length of a constant current charging section based on the SOC, the internal resistance, and the at least one parameter of the battery;
estimate a time length of a constant voltage charging section based on the SOC, the internal resistance, and the at least one parameter of the battery;
estimate a charging current of the battery in a unit of an SOC step based on the SOC, the internal resistance, and the at least one parameter of the battery; and
calculate the time length of the constant voltage charging section in the unit of the SOC step based on the SOC, the at least one parameter, and the charging current of the battery.

10 . The apparatus of claim 9 , wherein the at least one parameter comprises a voltage, a current, and a temperature of the battery.

11 . The apparatus of claim 9 , wherein:
the internal resistance of the battery comprises a first internal resistance, an estimated internal resistance, a second internal resistance, and a third internal resistance; the first internal resistance is calculated with respect to the SOC of the battery based on SOC-internal resistance data of the battery; the estimated internal resistance is estimated by calculating an OCV of the battery based on the SOC-OCV data, the SOC of the battery, and a difference between the OCV and a voltage of the battery; the second internal resistance is estimated with respect to a plurality of SOC grid points, based on a linear regression equation, the estimated internal resistance, and the SOC; and the third internal resistance is calculated with respect to the plurality of SOC grid points based on the first internal resistance and the second internal resistance.

12 . The apparatus of claim 11 , wherein the linear regression equation is derived based on the estimated internal resistance as a Y value and the SOC as an X value.

13 . The apparatus of claim 11 , wherein the plurality of SOC grid points indicate, based on the SOC of the battery on a horizontal axis and the internal resistance of the battery on a vertical axis, points for estimating the internal resistance of the battery with respect to an SOC of the horizontal axis.

14 . The apparatus of claim 11 , wherein the third internal resistance is calculated by adding the first internal resistance and an internal resistance update value, and
the internal resistance update value is calculated by multiplying a difference between the first internal resistance and the second internal resistance by a coefficient.

15 . The apparatus of claim 9 , wherein the SOC step represents a reference value dividing the constant current charging section and the constant voltage charging section, by an SOC unit, between a start SOC of the battery at a time point at which charging of the battery starts and an end SOC at a time point at which the charging is completed.

Assignees

• Samsung Sdi Co Ltd

Inventors

• Shim Youngwoo
• Cho Youngshin

Classifications

• H02J7/445

  in response to measured battery parameters, e.g. voltage, current or temperature profile · CPC title

• H02J7/825 Primary

  Detection of fully charged condition · CPC title

• H02J7/92

  with prioritisation of loads or sources · CPC title

• H02J7/82

  Control of state of charge [SOC] · CPC title

• H02J7/80 Primary

  including monitoring or indicating arrangements · CPC title