[go: up one dir, main page]

CN114035069A - Lithium battery full SOC compression modulus evaluation method - Google Patents

Lithium battery full SOC compression modulus evaluation method Download PDF

Info

Publication number
CN114035069A
CN114035069A CN202111292373.7A CN202111292373A CN114035069A CN 114035069 A CN114035069 A CN 114035069A CN 202111292373 A CN202111292373 A CN 202111292373A CN 114035069 A CN114035069 A CN 114035069A
Authority
CN
China
Prior art keywords
soc
battery cell
pressure
initial
compression modulus
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN202111292373.7A
Other languages
Chinese (zh)
Inventor
王益
齐琼琼
魏奕民
黄垲焱
张兴华
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Initial Energy Science & Technology Xiamen Co ltd
Original Assignee
Initial Energy Science & Technology Xiamen Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Initial Energy Science & Technology Xiamen Co ltd filed Critical Initial Energy Science & Technology Xiamen Co ltd
Priority to CN202111292373.7A priority Critical patent/CN114035069A/en
Publication of CN114035069A publication Critical patent/CN114035069A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R31/00Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
    • G01R31/36Arrangements for testing, measuring or monitoring the electrical condition of accumulators or electric batteries, e.g. capacity or state of charge [SoC]
    • G01R31/382Arrangements for monitoring battery or accumulator variables, e.g. SoC
    • G01R31/3842Arrangements for monitoring battery or accumulator variables, e.g. SoC combining voltage and current measurements

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Secondary Cells (AREA)

Abstract

The invention relates to a lithium battery full SOC compression modulus evaluation method, which comprises the following steps: step 1, selecting two identical full discharge electric cores to respectively carry out constant pressure and constant gap tests; step 2, constant pressure testing: keeping the initial pressure unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording the corresponding battery cell thickness variation when the SOC of the battery cell gradually rises from 0% to 100% in real time; step 3, keeping the initial gap unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording a corresponding pressure value when the SOC of the battery cell gradually rises from 0% to 100%; and 4, obtaining the thickness variation and the pressure value of the battery cell under the corresponding SOC according to the steps 2 and 3, and drawing a strain-stress curve, wherein the slope of each point of the curve corresponds to the compression modulus of the SOC corresponding to the point. The method can obtain the compression modulus of the lithium battery in the full SOC state.

Description

Lithium battery full SOC compression modulus evaluation method
Technical Field
The invention relates to the field of lithium battery performance measurement, in particular to a lithium battery full SOC compression modulus evaluation method.
Background
The expansion behavior of the lithium ion battery cell in the charging and discharging process has two expression forms: thickness and stress, accurate measurement help optimizing electric core design and promote the security performance of battery in the use.
The general method adopts a universal tester for testing, which is to measure the compression modulus of the battery cell under a fixed state (such as charging 10% and charging 20%), wherein a change curve of the compression modulus is a discrete point (namely, the SOC is the compression modulus corresponding to 10% and the SOC is the compression modulus corresponding to 20%), and the compression modulus of the battery cell under a continuous full SOC state (namely, when the SOC range is 0% to 100%, the compression modulus corresponding to the SOC can be found by arbitrarily taking an SOC value in the range) cannot be intuitively and accurately represented.
Object of the Invention
Aiming at the problems in the prior art, the invention aims to provide a method for evaluating the full SOC compression modulus of a lithium battery so as to obtain the compression modulus in a full SOC state.
In order to achieve the purpose, the invention adopts the technical scheme that:
a lithium battery full SOC compression modulus evaluation method comprises the following steps:
step 1, selecting two identical full discharge electric cores to respectively carry out constant pressure and constant gap tests;
step 2, constant pressure testing: applying an initial pressure to the cell to obtain the initial thickness of the cell under the constant pressure; then keeping the initial pressure unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording the corresponding battery cell thickness variation when the SOC of the battery cell gradually rises from 0% to 100% in real time;
step 3, constant gap testing: applying an initial pressure to the battery cell, and measuring a pressing plate gap of the battery cell to be an initial gap; keeping the initial gap unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording a pressure value corresponding to the gradual increase of the SOC of the battery cell from 0% to 100%; the pressure value is the pressure applied when the initial clearance of the battery core needs to be kept unchanged;
and 4, obtaining the thickness variation and the pressure value of the battery cell under the corresponding SOC according to the steps 2 and 3, drawing a strain-stress curve by taking the two parameters as the strain and the stress of the battery cell, wherein the slope of each point of the strain-stress curve corresponds to the compression modulus of the SOC corresponding to the point, and thus, the compression modulus of the lithium battery under the full SOC state is obtained.
In the step 2, after the battery cell thickness variation is recorded, a battery cell thickness variation-SOC curve is drawn.
In the step 3, after the voltage is recorded, a pressure-SOC curve is drawn.
By adopting the scheme, the compression modulus of the lithium battery in the full SOC state can be obtained, the mechanical property of the battery cell is evaluated, the manufacturing process is guided, and the formula is improved; and evaluating the aging degree of the battery cell through the complete compression modulus of the battery cell, and better knowing the circulation state of the battery cell.
Drawings
FIG. 1 is a plot of expansion for different SOCs at constant pressure and constant gap;
fig. 2 is a schematic stress-strain curve.
Detailed Description
The invention discloses a lithium battery full SOC compression modulus evaluation method, which comprises the following steps:
step 1, selecting two identical full discharge electric cores to respectively carry out constant pressure and constant gap tests.
The constant pressure test and the constant gap test can be realized by adopting an in-situ expansion analyzer.
Step 2, constant pressure testing: applying an initial pressure (e.g., 10 kg) to the cell to obtain an initial thickness of the cell at the constant pressure; then, the initial pressure is kept unchanged, the battery cell is charged from a fully discharged state to a fully charged state, data such as the battery cell thickness variation, the current, the voltage, the capacity and the like corresponding to the gradual increase of the SOC of the battery cell from 0% to 100% are recorded in real time, and a battery cell thickness variation-SOC curve is drawn (as shown in fig. 1).
Step 3, constant gap testing: applying an initial pressure (e.g., 10 kg) to the cell, and measuring the platen gap of the cell to be an initial gap; keeping the initial gap unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording a pressure value corresponding to the gradual increase of the SOC of the battery cell from 0% to 100%; the pressure value refers to data such as pressure, current, voltage, capacity and the like applied when the initial gap of the battery cell needs to be kept unchanged, and a pressure-SOC curve is drawn (as shown in fig. 1).
In the above steps 2 and 3, the data of current, voltage capacity, etc. and the variation-SOC curve and the pressure-SOC curve can be used to determine whether the result of the test data is normal.
And 4, obtaining the thickness variation and the pressure value of the battery cell under the corresponding SOC according to the steps 2 and 3, drawing a strain-stress curve (shown in fig. 2) by taking the two parameters as the strain and the stress of the battery cell, wherein the slope of each point of the curve corresponds to the compression modulus of the SOC corresponding to the point, and thus, the compression modulus of the lithium battery under the full SOC state is obtained.
In conclusion, the method can obtain the compression modulus of the lithium battery in the full SOC state, evaluate the mechanical property of the battery core, guide the manufacturing process and improve the formula; and evaluating the aging degree of the battery cell through the complete compression modulus of the battery cell, and better knowing the circulation state of the battery cell.
The above description is only exemplary of the present invention and is not intended to limit the technical scope of the present invention, so that any minor modifications, equivalent changes and modifications made to the above exemplary embodiments according to the technical spirit of the present invention are within the technical scope of the present invention.

Claims (3)

1. A lithium battery full SOC compression modulus evaluation method is characterized in that: the method comprises the following steps:
step 1, selecting two identical full discharge electric cores to respectively carry out constant pressure and constant gap tests;
step 2, constant pressure testing: applying an initial pressure to the cell to obtain the initial thickness of the cell under the constant pressure; then keeping the initial pressure unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording the corresponding battery cell thickness variation when the SOC of the battery cell gradually rises from 0% to 100% in real time;
step 3, constant gap testing: applying an initial pressure to the battery cell, and measuring a pressing plate gap of the battery cell to be an initial gap; keeping the initial gap unchanged, charging the battery cell from a fully discharged state to a fully charged state, and recording a pressure value corresponding to the gradual increase of the SOC of the battery cell from 0% to 100%; the pressure value is the pressure applied when the initial clearance of the battery core needs to be kept unchanged;
and 4, obtaining the thickness variation and the pressure value of the battery cell under the corresponding SOC according to the steps 2 and 3, drawing a strain-stress curve by taking the two parameters as the strain and the stress of the battery cell, wherein the slope of each point of the strain-stress curve corresponds to the compression modulus of the SOC corresponding to the point, and thus, the compression modulus of the lithium battery under the full SOC state is obtained.
2. The method for evaluating the full SOC compressive modulus of a lithium battery according to claim 1, wherein: in the step 2, after the battery cell thickness variation is recorded, a battery cell thickness variation-SOC curve is drawn.
3. The method for evaluating the full SOC compressive modulus of a lithium battery according to claim 1, wherein: in the step 3, after the voltage is recorded, a pressure-SOC curve is drawn.
CN202111292373.7A 2021-11-03 2021-11-03 Lithium battery full SOC compression modulus evaluation method Pending CN114035069A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111292373.7A CN114035069A (en) 2021-11-03 2021-11-03 Lithium battery full SOC compression modulus evaluation method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111292373.7A CN114035069A (en) 2021-11-03 2021-11-03 Lithium battery full SOC compression modulus evaluation method

Publications (1)

Publication Number Publication Date
CN114035069A true CN114035069A (en) 2022-02-11

Family

ID=80136111

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111292373.7A Pending CN114035069A (en) 2021-11-03 2021-11-03 Lithium battery full SOC compression modulus evaluation method

Country Status (1)

Country Link
CN (1) CN114035069A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119714183A (en) * 2023-09-28 2025-03-28 宁德时代新能源科技股份有限公司 Method, device and medium for determining stress-strain relation of battery cell

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20130087042A (en) * 2010-11-17 2013-08-05 미쓰이금속광업주식회사 Copper foil for lithium ion secondary battery negative electrode collector, lithium ion secondary battery negative electrode material, and method for selecting lithium ion secondary battery negative electrode collector
CN105466777A (en) * 2015-12-14 2016-04-06 成都慧成科技有限责任公司 Method for detecting pressure resistant performance of microporous film
CN107683301A (en) * 2015-06-19 2018-02-09 宇部兴产株式会社 Polyolefin microporous film, separator film for electrical storage device, and electrical storage device
CN110783635A (en) * 2018-07-30 2020-02-11 丰田自动车株式会社 All-solid-state battery and method of making the same
CN111129386A (en) * 2019-12-27 2020-05-08 苏州清陶新能源科技有限公司 Foam type selection method for battery module and battery module
CN113504475A (en) * 2021-04-29 2021-10-15 浙江南都电源动力股份有限公司 Device and method for evaluating expansion behavior of lithium battery

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20130087042A (en) * 2010-11-17 2013-08-05 미쓰이금속광업주식회사 Copper foil for lithium ion secondary battery negative electrode collector, lithium ion secondary battery negative electrode material, and method for selecting lithium ion secondary battery negative electrode collector
CN107683301A (en) * 2015-06-19 2018-02-09 宇部兴产株式会社 Polyolefin microporous film, separator film for electrical storage device, and electrical storage device
CN105466777A (en) * 2015-12-14 2016-04-06 成都慧成科技有限责任公司 Method for detecting pressure resistant performance of microporous film
CN110783635A (en) * 2018-07-30 2020-02-11 丰田自动车株式会社 All-solid-state battery and method of making the same
CN111129386A (en) * 2019-12-27 2020-05-08 苏州清陶新能源科技有限公司 Foam type selection method for battery module and battery module
CN113504475A (en) * 2021-04-29 2021-10-15 浙江南都电源动力股份有限公司 Device and method for evaluating expansion behavior of lithium battery

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN119714183A (en) * 2023-09-28 2025-03-28 宁德时代新能源科技股份有限公司 Method, device and medium for determining stress-strain relation of battery cell

Similar Documents

Publication Publication Date Title
Jiang et al. State of health estimation of second-life LiFePO4 batteries for energy storage applications
CN107045103B (en) Device and method for testing service life of power battery of electric automobile
CN107015156B (en) A battery health state detection method and device
CN106680726B (en) Method for testing cycle performance of lithium ion battery
CN115097338B (en) SOC calibration method, SOH estimation method, device and storage medium
WO2020090143A1 (en) Battery diagnosis device and battery diagnosis method using current pulse method
CN103326076B (en) A kind of electrokinetic cell recycling method
CN111999610A (en) Dry-type insulation equipment aging evaluation and service life prediction method based on activation energy
CN113533988A (en) Long-term circulation capacity attenuation analysis method for lithium ion battery
CN108490366A (en) The fast evaluation method of the retired battery module health status of electric vehicle
Thingvad et al. Characterization of nmc lithium-ion battery degradation for improved online state estimation
CN111077456A (en) Nondestructive testing method for lithium separation of lithium ion battery
JP2024511082A (en) Methods, devices and computer program products for calculating capacity loss of power storage devices
CN111965557A (en) Backup power reliability assessment method and device
CN109633475A (en) Lithium iron phosphate energy type battery life estimation method
CN111413626B (en) Prediction method and device for fuel cell service life based on polarization-like characteristics
CN114035069A (en) Lithium battery full SOC compression modulus evaluation method
CN114695990B (en) A method, device, equipment and medium for determining capacity balance of a battery system
CN108020788A (en) A rapid screening method for lithium-ion battery internal resistance
CN116243172A (en) Method for rapidly detecting reliability state of lithium battery
CN116774043A (en) Retired lithium ion battery residual life detection method based on frequency screening
CN113761716B (en) Lithium ion battery cycle life prediction method and application thereof
CN118708954A (en) A rapid battery life assessment method based on actual operating conditions
CN114487852A (en) Power battery residual energy detection method, device, computer equipment and storage medium
CN110658463B (en) Method for predicting cycle life of lithium ion battery

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20220211

WD01 Invention patent application deemed withdrawn after publication