Control of Lithium Plating of Lithium-Ion Battery During Charging

Patent metadata

Field	Value
Publication number	US-2022069361-A1
Application number	US-202017002380-A
Country	US
Kind code	A1
Filing date	Aug 25, 2020
Priority date	Aug 25, 2020
Publication date	Mar 3, 2022
Grant date	—

Abstract

A method of controlling the charge current during charging of a lithium-ion battery. A battery charging controller is based on a Kalman filter, which uses estimated battery states to generate a feedback metric to continually adjust a battery cell model. The battery cell model then delivers data to an optimization process that generates the charge current.

First claim

What is claimed is:

1 . A method of controlling the charge current during charging of a lithium-ion battery, comprising:
storing a cell model of the battery as part of a cell model process; measuring battery state values of the battery, the battery states being at least: the battery's electrolyte overpotential and the battery's polarization resistance; delivering the battery state values to a Kalman filter process; processing the battery state values with the Kalman filter process to obtain a cell model adjustment factor; wherein the cell model process is programmed to receive the cell model adjustment factor and a charge current value, and based on the cell model, the cell model adjustment factor, and the charge current value, to generate a model state vector having one or more model state values representing at least the battery's state of charge; and using an optimization process to generate a new charge current based on the model state vector and the charge current value.

2 . The method of claim 1 , wherein the battery is a vehicle battery.

3 . The method of claim 1 , wherein the method is implemented as part of a battery management system of a vehicle battery.

4 . The method of claim 1 , wherein the model state vector further has model states of one or more of the following: anode potential, electrolyte potential, or solid electrolyte interphase layer resistance.

5 . The method of claim 1 , wherein the step of measuring battery state values is performed by a battery management system.

6 . The method of claim 1 , wherein polarization resistance is measured while the battery is hooked up to a charger and its charge is complete and stopped.

7 . The method of claim 1 , wherein the cell model is a reduced order model.

8 . The method of claim 1 , wherein the adjustment factor adjusts values in the cell model related to electrode and electrolyte potentials.

9 . A controller for controlling the charge current during charging of a lithium-ion battery, comprising:
a cell model process that stores a model of the battery; a Kalman filter process operable to receive measured battery state values of the battery, the battery states being at least: the battery's electrolyte overpotential and the battery's polarization resistance; wherein the Kalman filter process processes the battery state values to obtain a cell model adjustment factor; wherein the cell model process is programmed to receive the cell model adjustment factor and a charge current value, and based on the cell model, the cell model adjustment factor, and the charge current value, to generate a model state vector having one or more model state values representing at least the battery's state of charge; and an optimization process operable to generate a new charge current based on the model state vector and the charge current value.

10 . The controller of claim 9 , wherein the battery is a vehicle battery.

11 . The controller of claim 9 , wherein the controller is part of a battery management system of a vehicle battery.

12 . The controller of claim 9 , wherein the model state vector further has model states of one or more of the following: anode potential, electrolyte potential, or solid electrolyte interphase layer resistance.

13 . The controller of claim 9 , wherein polarization resistance is measured while the battery is hooked up to a charger and its charge is complete and stopped.

14 . The controller of claim 9 , wherein the cell model is a reduced order model.

15 . The controller of claim 9 , wherein the adjustment factor adjusts values in the cell model related to electrode and electrolyte potentials.

16 . An improved battery management system for an electric vehicle having at least one lithium-ion battery, the improvement comprising:
a measurement process for measuring or estimating battery state values, the battery state values being at least: the battery's electrolyte overpotential and the battery's polarization resistance; a charging controller for controlling the charge current during charging of the battery, comprising: a cell model process that stores a model of the battery; a Kalman filter process operable to receive the battery state values and to process the battery state values to obtain a cell model adjustment factor; wherein the cell model process is programmed to receive the cell model adjustment factor and a charge current value, and based on the cell model, the cell model adjustment factor, and the charge current value, to generate a model state vector having one or more model state values representing at least the battery's state of charge; and an optimization process operable to generate a new charge current based on the model state vector and the charge current value.

Assignees

• Southwest Res Inst

Inventors

• Surampudi Bapiraju
• Jones Kevin

Classifications

• H01M10/484

  for measuring electrolyte level, electrolyte density or electrolyte conductivity · CPC title

• H02J7/933

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

• Y02E60/10

  Energy storage using batteries · CPC title

• H01M10/0525

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

• H01M10/425 Primary

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