Estimation method for state of health (SOH) of electric vehicle lithium battery

A technology for electric vehicles and lithium batteries, which is applied in the direction of measuring electricity, measuring electrical variables, measuring devices, etc., and can solve problems such as particle degradation, large amount of calculation, loss of particle diversity, etc.

Inactive Publication Date: 2018-12-21
SHANGHAI UNIVERSITY OF ELECTRIC POWER
View PDF6 Cites 25 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In general, the particle filter algorithm has certain advantages for solving nonlinear non-Gaussian systems, but in the process of implementation, problem

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Estimation method for state of health (SOH) of electric vehicle lithium battery
  • Estimation method for state of health (SOH) of electric vehicle lithium battery
  • Estimation method for state of health (SOH) of electric vehicle lithium battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0076] This embodiment provides the implementation of the content of the invention, which is divided into four steps.

[0077] 1. Build a model

[0078] Such as figure 1 As shown, according to Kirchhoff's voltage and current law, the circuit equation of the model is:

[0079] U=U OCV (SOC)-IR 0 -U p1 -U p2 (2)

[0080]

[0081] where R 0 is the ohmic internal resistance, U OCV (SOC) is the open circuit voltage, which has a nonlinear relationship with SOC, R pi (i=1,2) is the polarization internal resistance, C pi (i=1,2) is the polarized capacitance, U pi (i=1,2) is the polarization voltage, I is the charging and discharging current of the battery, and U is the terminal voltage.

[0082] Select the voltage U of the two RC links p1 and U p2 , ohmic internal resistance R 0 In addition, SOC is used as the state variable of the system, and the terminal voltage of the battery is selected as the observation quantity. The state equation is constructed as shown in eq...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention relates to an estimation method for state of health (SOH) of an electric vehicle lithium battery. The estimation method is characterized by comprising the following steps of 1) buildinga second-order equivalent model of a battery lithium battery; 2) identifying a parameter of the second-order equivalent model, wherein the parameter comprises ohmic internal resistance R0 and a second-order RC link parameter; 3) calculating the ohmic internal resistance R0 by employing an improved UPF method; and 4) calculating an SOH value of the power lithium battery. Compared with the prior art, the estimation method has the advantages of high tracking forecast capability, high estimation accuracy and the like.

Description

technical field [0001] The invention relates to the technical field of power lithium batteries, in particular to a method for estimating the SOH of lithium batteries for electric vehicles. Background technique [0002] The global oil resources are depleting day by day, and the environmental pollution and energy crisis caused by the popularization of fuel vehicles have aroused people's attention. As an environment-friendly and resource-saving means of transportation, electric vehicles have prompted countries all over the world to invest a lot of manpower and material resources in the research and development of electric vehicles. As the core component of electric vehicles, the development of power batteries is bound to play a key role in the performance of electric vehicles. At present, lithium-ion batteries have the best application prospects in electric vehicles, and the research on their performance has become a hot spot in recent years. The state parameters that characte...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01R31/36
Inventor 夏飞施恩威彭道刚孟娟钱玉良
Owner SHANGHAI UNIVERSITY OF ELECTRIC POWER
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products