Self-discharge detection method of lithium iron phosphate battery

A lithium iron phosphate battery and detection method technology, applied in the direction of measuring electricity, measuring devices, measuring electrical variables, etc., can solve the problems that cannot reflect the actual situation of a single battery, require high parameter accuracy, and take a long time to test. Accurate and effective, improve product quality, eliminate the effect of polarization

Active Publication Date: 2015-01-28
中创新航科技(江苏)有限公司
View PDF15 Cites 45 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method has high requirements on the accuracy of the parameters in the formula, and adopts a unified empirical value. Due to the differences of each battery, it cannot reflect the actual situation of a single battery. Therefore, it is necessary to check the capacity of the single battery, The platform and internal resistance are divided into files, and the test time is relatively long, about 7 days

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
  • Self-discharge detection method of lithium iron phosphate battery
  • Self-discharge detection method of lithium iron phosphate battery
  • Self-discharge detection method of lithium iron phosphate battery

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] Taking a lithium iron phosphate battery with a capacity of 100AH ​​as an example, first charge and discharge the lithium iron phosphate battery at a rate of 0.5C for 3 times, discharge to 2.5V at a rate of 0.3C, leave it for 30min, and then discharge to 2.5V at a rate of 0.05C. V; put it aside for 30 minutes, charge it to 3.21V with a constant current of 0.1C, let the battery stand at room temperature 20°C for 12 hours, test and record the open circuit voltage OCV 1 ;The battery was left standing at a high temperature of 50°C for 48 hours, and the open circuit voltage OCV was tested and recorded. 2 , calculate K=OCV 1 -OCV 2 After that, test the charge retention data of all the batteries in the group according to the GB / T743-2006 charge retention method, as shown in Table 1:

[0041]

[0042]

[0043] It can be concluded from Table 1 that when K>7.0mV, the charge retention rate of the battery is less than 94%, and when K<7.0mV, the charge retention rate of the bat...

Embodiment 2

[0045] Taking a lithium iron phosphate battery with a capacity of 100AH ​​as an example, first charge and discharge the lithium iron phosphate battery at a rate of 0.5C for 3 times, discharge to 2.5V at a rate of 0.3C, leave it for 30min, and then discharge to 2.5V at a rate of 0.05C. V, put it aside for 30 minutes, charge it to 3.21V with a constant current of 0.1C, test and record the open circuit voltage OCV1 when the battery stands at room temperature 20°C for 12 hours; test and record the open circuit voltage OCV2 when the battery stands at a high temperature of 50°C for 84 hours; calculate Get K=OCV 1 -OCV 2 After that, all the batteries in the group are tested for the charge retention data according to the GB / T743-2006 charge retention method, as shown in Table 2:

[0046]

[0047]

[0048] It can be concluded from Table 2 that when K>10.0mV, the charge retention rate of the battery is less than 94%, and if K<10.0mV, the charge retention rate of the battery is gr...

Embodiment 3

[0050] Taking a lithium iron phosphate battery with a capacity of 100AH ​​as an example, first charge and discharge the lithium iron phosphate battery at a rate of 0.5C for 3 times, discharge to 2.5V at a rate of 0.3C, leave it for 30min, and then discharge to 2.5V at a rate of 0.05C. V; put it aside for 30 minutes, charge it to 3.29V with a constant current of 0.1C, let the battery stand at room temperature 20°C for 12 hours, test and record the open circuit voltage OCV 1 ;The battery was left standing at a high temperature of 50°C for 48 hours, and the open circuit voltage OCV was tested and recorded. 2 , calculate K=OCV 1 -OCV 2 After that, test the charge retention data of all the batteries in the group according to the GB / T743-2006 charge retention method, as shown in Table 3:

[0051]

[0052]

[0053] It can be concluded from Table 3 that the voltage changes slowly in this state of charge, and the overall K value is small, which is easily disturbed by other fact...

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 discloses a self-discharge detection method of a lithium iron phosphate battery. Charging and discharging pretreatment is carried out on lithium iron phosphate batteries after capacity sorting processing; the batteries are placed for standing for some time respectively in different temperature environments and open-circuit voltages OCV1 and OCV2 are tested; a difference value K between the OCV1 and the OCV2 is calculated; and according to the K value, a battery with a high self-discharge value is determined and selected. According to the invention, the electrode polarization is eliminated by pretreatment, so that the influence on the voltage by polarization and unstable system factors can be minimized; and the battery with the high self-discharge value can be screened out rapidly in short time before grouping. The test is accurate and effective; the product quality is substantially improved; and the consistency of the whole group of batteries can be prevented from being influenced by the battery with the high self-discharge value. Therefore, the service life of the battery group can be prolonged.

Description

technical field [0001] The invention belongs to the technical field of lithium-ion power batteries, and in particular relates to a self-discharge detection method of a lithium-ion iron phosphate battery. Background technique [0002] With the development of the electric vehicle industry, since lithium iron phosphate batteries have better safety performance and longer life than other lithium-ion batteries, it has become a trend for lithium iron phosphate batteries to be used in electric vehicles. [0003] When the storage battery and primary battery are not connected to the external circuit, the loss of battery capacity caused by the internal white hair reaction is generally called self-discharge. It is expressed by the percentage of capacity lost per year or per month. For example, the self-discharge of various lithium-ion batteries is very small, about 1-2% per month, and the metal hydride battery is relatively large, reaching more than 10% per month. Due to the uncertaint...

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 张岩徐文娟李严周志勇刘露露党友旗
Owner 中创新航科技(江苏)有限公司
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