Lithium ion battery charge state estimating method

A battery state of charge, lithium-ion battery technology, applied in the field of electric vehicle batteries, to achieve accurate battery characteristics, improve rationality and accuracy, and facilitate engineering applications

Active Publication Date: 2015-04-22
JILIN UNIV
View PDF10 Cites 49 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to adopt an estimation method based on a parameter time-varying observer to solve the lithium-ion battery state of charge estimation method when the lithium-ion battery is charged and discharged at different rates.

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
  • Lithium ion battery charge state estimating method
  • Lithium ion battery charge state estimating method
  • Lithium ion battery charge state estimating method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0104] Embodiment: Take the lithium-ion battery of 1650mAH as object

[0105] 1. Use the above battery capacity test to calculate the capacity of the lithium-ion battery .

[0106] 2. Using the above test of the relationship between open circuit voltage (OCV) and SOC and the upper limit of hysteresis voltage, record the relationship data between charge and discharge open circuit voltage (OCV) and battery state of charge SOC, and calculate the rest period of each interval point of lithium-ion battery The minimum value of , as shown in Table 1. According to the results in Table 1, the upper bound of the hysteresis voltage is obtained by further calculation .

[0107] Table 1 Relationship between open circuit voltage (OCV) and SOC

[0108]

[0109] 3. Using equivalent internal resistance , polarization resistance , polarized capacitance with current To test the relationship, record the constant current value before standing and the battery terminal voltage curve ...

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 a lithium battery charge state estimating method and belongs to the technical field of batteries of electric vehicles. The lithium battery charge state estimating method aims at estimating the charge state of a lithium battery under the complex working conditions of charging and discharging at different multiplying power levels through an estimation method based on a parameter time varying observer. The lithium battery charge state estimating method specifically comprises the step that a battery charge state is regarded as a state variable to be introduced into a lithium ion battery continuous model, the upper limit of hysteresis voltages is determined according to the charging and discharging open-circuit voltage, the battery hysteresis phenomenon is considered to be a first order dynamic process related to the current absolute value, a battery polarization voltage model with parameters changing along with currents and an internal resistance model with parameters changing along with currents are structured through RC rings, battery model end voltages are structured, and a nonlinear parameter time-varying battery model is obtained. The lithium battery charge state estimating method is based on a parameter time-varying lithium ion battery equivalent circuit model, the model parameters are calibrated to be a function of current multiplying power, the characteristics of the battery can be accurately expressed, and meanwhile an existing estimation method can be easily used.

Description

technical field [0001] The invention belongs to the technical field of electric vehicle batteries. Background technique [0002] The battery state of charge (State of Charge, SOC) is used to represent the remaining power of the battery, that is, the percentage of the remaining power to the rated capacity, and its value is theoretically in the range of 0% to 100%. The state of charge of the battery cannot be obtained directly from the battery itself, but can only be estimated indirectly by measuring the external characteristic parameters of the battery pack (such as voltage, current, internal resistance, temperature, etc.). During the use of lithium-ion batteries for electric vehicles, due to the internal complex electrochemical reaction phenomena, the battery characteristics show a high degree of nonlinearity (time-varying parameters of charge and discharge, hysteresis, etc.), which makes it very important to accurately estimate the state of charge of the battery. difficult...

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
Patent Type & Authority Applications(China)
IPC IPC(8): G01R31/36
Inventor 王宇雷张吉星马彦陈虹
Owner JILIN UNIV
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap