A method for testing and diagnosing the causes of lithium-ion battery performance attenuation

A lithium-ion battery and diagnostic method technology, which is applied in the field of testing and diagnosis of the causes of lithium-ion battery performance attenuation, can solve problems such as deviation from the original state of the battery, insufficient sensitivity, and influence on judgment results, and achieve the effect of improving accuracy

Active Publication Date: 2018-01-02
TIANJIN LISHEN BATTERY +1
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the reassembly process after battery disassembly may deviate from the original state of the battery, which may affect the judgment result
At the same time, conventional SEM, XRD and other material characterization methods are not sensitive enough to characterize materials with slight structural changes.

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
  • A method for testing and diagnosing the causes of lithium-ion battery performance attenuation
  • A method for testing and diagnosing the causes of lithium-ion battery performance attenuation
  • A method for testing and diagnosing the causes of lithium-ion battery performance attenuation

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] The test battery model is 18650 cylindrical battery, the reference battery capacity is 2500mAh (1C=2500mA), and the 0.5C discharge capacity retention rate of the battery to be tested is 80% (350 cycles), that is, 2000mAh (1C=2000mA).

[0034] First, take the battery to be tested and the reference battery, and conduct a 0.1C capacity test on the Arbin charge-discharge instrument, and draw the dQ / dV vs. state of charge (SOC) curve of the battery according to the voltage and capacity data, as shown in figure 1 shown by figure 1 It can be seen that the main electrochemical reaction range of the system battery corresponds to a battery charge state range of 25%-55%, and in this embodiment, the preferred charge state range is 40%.

[0035] 1) Measure the ohmic impedance and relaxation impedance of the battery during charging (discharging):

[0036] Charge with a small current of 0.1C for 4h (discharge for 6h) to 40% state of charge, then charge (discharge) with a current of 1...

Embodiment 2

[0047] In this embodiment, the test battery model is a 18650 cylindrical battery, the reference battery capacity is 2300mAh (1C=2300mA), and the 0.5C discharge capacity retention rate of the battery to be tested is 80% (800 cycles), that is, 1840mAh (1C = 1840mA).

[0048] In this embodiment, the SOC interval of the direct selection test is 40%.

[0049] 1) Measure the ohmic impedance and relaxation impedance of the battery during charging (discharging):

[0050] The method of measuring the ohmic impedance and relaxation impedance of the battery during the charging (discharging) process is to charge with a small current of 0.1C for 4h (discharge for 6h) to 40% state of charge, then charge (discharge) with a current of 1C for 1s, and collect voltage data The interval is 60ms, and the last voltage value is recorded as Uo, sleep, within 1s after sleep starts, the interval of collecting voltage data is 60ms, the first collected voltage value is recorded as Ui, and the collection ...

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 method for testing and diagnosing the cause of performance attenuation of a lithium-ion battery, comprising measuring the ohmic impedance and relaxation impedance of a battery to be tested and a reference battery during charging and discharging under a certain state of charge; The temperature entropy coefficient of the battery to be tested and the reference battery; calculate the ohmic impedance growth rate and relaxation impedance growth rate and the absolute value of the temperature entropy coefficient growth rate of the battery relative to the reference battery in the charging and discharging process; Comparing the ohmic impedance growth rate and relaxation impedance growth rate and the absolute value of the temperature entropy coefficient growth rate of the battery under test relative to the reference battery, the cause of battery performance attenuation can be judged. The invention avoids the influence of other factors introduced into the assembly process after the battery is disassembled, and greatly improves the accuracy of testing and judgment; and the operation process and method are simple, which is convenient for testing multiple battery samples and establishing a corresponding database, which can reduce battery performance attenuation. Analysis provides reliable reference data.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion battery testing, and in particular relates to a testing and diagnosis method for the cause of lithium-ion battery performance attenuation. Background technique [0002] At the current stage, lithium-ion batteries are widely used in electronic consumer products due to their irreplaceable advantages, and their applications in military, aerospace, energy storage, and electric vehicles are gradually increasing. [0003] For battery developers, according to different use environments and performance requirements, it is necessary to carry out corresponding design and verification tests on the battery system, and in the verification test, it is necessary to analyze the causes of batteries with performance attenuation or substandard performance, which has reached Optimization and improvement of battery design. [0004] The conventional method is to disassemble the battery and conduct characterization...

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 Patents(China)
IPC IPC(8): G01R31/36
Inventor 李慧芳李飞纪书文马佳鑫
Owner TIANJIN LISHEN BATTERY
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