CN111282853A - Screening method of lithium ion battery - Google Patents
Screening method of lithium ion battery Download PDFInfo
- Publication number
- CN111282853A CN111282853A CN202010129255.3A CN202010129255A CN111282853A CN 111282853 A CN111282853 A CN 111282853A CN 202010129255 A CN202010129255 A CN 202010129255A CN 111282853 A CN111282853 A CN 111282853A
- Authority
- CN
- China
- Prior art keywords
- capacity
- discharge
- screening
- battery
- lithium ion
- 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
Links
- 238000012216 screening Methods 0.000 title claims abstract description 50
- 238000000034 method Methods 0.000 title claims abstract description 29
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims abstract description 18
- 229910001416 lithium ion Inorganic materials 0.000 title claims abstract description 18
- 238000012360 testing method Methods 0.000 claims abstract description 14
- 230000014759 maintenance of location Effects 0.000 claims abstract description 13
- 238000011084 recovery Methods 0.000 claims abstract description 13
- 208000028659 discharge Diseases 0.000 claims description 42
- 238000007600 charging Methods 0.000 claims description 14
- 238000010277 constant-current charging Methods 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 5
- 238000007599 discharging Methods 0.000 claims description 5
- 230000009286 beneficial effect Effects 0.000 description 2
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 1
- 238000010280 constant potential charging Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 229910052744 lithium Inorganic materials 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07C—POSTAL SORTING; SORTING INDIVIDUAL ARTICLES, OR BULK MATERIAL FIT TO BE SORTED PIECE-MEAL, e.g. BY PICKING
- B07C5/00—Sorting according to a characteristic or feature of the articles or material being sorted, e.g. by control effected by devices which detect or measure such characteristic or feature; Sorting by manually actuated devices, e.g. switches
- B07C5/34—Sorting according to other particular properties
- B07C5/344—Sorting according to other particular properties according to electric or electromagnetic properties
Landscapes
- Secondary Cells (AREA)
- Charge And Discharge Circuits For Batteries Or The Like (AREA)
Abstract
The invention discloses a screening method of lithium ion batteries, which comprises the following steps of carrying out charge and discharge tests on the batteries at normal temperature, screening according to discharge capacity Q, a capacity screening coefficient k, a median voltage screening coefficient l and a constant current charge ratio screening coefficient m of single batteries, then carrying out self-discharge consistency tests, and screening by calculating a capacity retention rate η and a capacity recovery rate η.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a screening method of a lithium ion battery.
Background
Energy and environment have become the most concern worldwide, and electric vehicles are beginning to be popularized and applied worldwide. Lithium ion batteries have been widely used in special power supply systems such as mobile phones, notebooks, and electric vehicles because of their advantages such as high energy density and short cycle life. Meanwhile, the requirements of people on the safety performance and the electrical performance of the lithium battery in the using process are higher and higher.
In the practical application process, a plurality of single batteries are required to form a battery pack through a series-parallel connection method, and the service performance of the battery pack is directly determined by the consistency of the capacity, the voltage, the self-discharge rate, the cycle life, the internal resistance and the like of the single batteries. Therefore, how to utilize a simple and reliable screening method to screen the single batteries with consistent performance to the maximum extent for forming the battery pack is beneficial to improving the performance and the service life of the battery pack, and has important significance for large-scale popularization and application of the lithium ion batteries.
Disclosure of Invention
Based on the technical problems in the background art, the invention provides a screening method of a lithium ion battery.
The invention provides a screening method of lithium ion batteries, which comprises the following steps:
s1, performing a plurality of charge-discharge cycles on a plurality of single batteries with rated capacity C at room temperature to obtain the discharge capacity Q, the median voltage U and the constant current charge ratio P of the single batteries, and calculating the average discharge capacity of all the single batteries
Mean discharge median voltage
Average constant current charge ratio
S2, calculating a screening coefficient k of the capacity of the single battery, a screening coefficient l of the median voltage and a screening coefficient m of the constant current charging ratio, wherein
S3, setting preset ranges of k, l and m, screening out single batteries with k, l and m values within the preset ranges and discharge capacity Q larger than rated capacity, and recording as primary screening batteries;
s4, performing self-discharge consistency test on the primary screened battery, and calculating a capacity retention rate η 1 and a capacity recovery rate η 2;
and S5, setting preset ranges of η 1 and η 2, and screening out the single batteries with the values of η 1 and η 2 within the preset ranges.
The preset ranges of the capacity screening coefficient k, the median voltage screening coefficient l and the constant current charging ratio screening coefficient m can be set automatically according to the strictness degree of screened batteries; for example, the preset range of the capacity screening coefficient k is: k is less than 1, and the preset range of the median voltage screening coefficient l is as follows: l is less than 0.06, and the preset range of the constant current charging ratio screening coefficient m is as follows: m is less than 0.25.
Preferably, the preset range of the capacity retention rate η 1 is η 1 > 95%, and the preset range of the capacity recovery rate η 2 is η 2 > 96%.
Preferably, in step S1, the number of charge and discharge cycles is 3 to 5.
Preferably, in step S5, the specific method for testing self-discharge consistency includes the following steps:
a. carrying out constant-current first charging on the single battery until the SOC reaches 50%, and recording the first charging capacity as Q1；
b. B, placing the battery after the first charging in the step a at high temperature, then cooling to normal temperature, carrying out constant current first discharging to lower limit cut-off voltage, and recording the first discharge capacity as Q2；
c. C, charging the battery discharged for the first time in the step b for the second time until the battery is fully charged;
d. c, performing constant-current secondary discharge on the battery charged for the second time in the step c to reach a lower limit cut-off voltage, and recording the discharge capacity of the battery for the second time as Q3Calculating a capacity retention rate and a capacity recovery rate, wherein the capacity retention rate η 1 is Q2/Q1Capacity recovery ratio η 2Q3/Q。
Preferably, in the step b, the high-temperature rest temperature is 45-60 ℃ and the time is 7 days.
Preferably, in the step b, the time for cooling to normal temperature is 5h-10 h.
Preferably, in step c, the specific method of the second charging is as follows: the constant current is charged to the upper limit cut-off voltage, and then the constant voltage is charged to the cut-off current, namely the full charge is realized.
Preferably, the charging and discharging cycle in the step S1 and the self-discharging consistency test in the step S4 use the same charging current, which is 0.33C-1C; the discharge current used was the same and was 0.33C-1C.
The invention has the following beneficial effects:
the battery is subjected to charge-discharge testing and self-discharge consistency testing, six parameters of discharge capacity Q, capacity screening coefficient k, median voltage screening coefficient l, constant current charge ratio screening coefficient m, capacity retention rate η 1 and capacity recovery rate η 2 are comprehensively screened, and the single batteries with consistent performance are screened to the maximum extent to form the battery pack, so that the performance and the service life of the battery pack are improved.
Drawings
Fig. 1 is a charge-discharge cycle curve of the No. 1 module and the No. 2 module in example 1 of the present invention, in which No. 1 corresponds to No. 1 module, and No. 2 corresponds to No. 2 module.
Detailed Description
The technical solution of the present invention will be described in detail below with reference to specific examples.
Example 1
A screening method of lithium ion batteries comprises the following steps:
s1, at room temperature, 30 square single batteries with models of IFP20100140-27Ah and rated capacity of 27Ah are subjected to charge-discharge circulation for 5 times by using current of 27A to obtain discharge capacity Q, median voltage U and constant current charge ratio P of the single batteries, and average discharge capacity of all the single batteries is calculated
Mean discharge median voltage
Average constant current charge ratio
S2, calculating a screening coefficient k of the capacity of the single battery, a screening coefficient l of the median voltage and a screening coefficient m of the constant current charging ratio, wherein
S3, setting the preset ranges of k, l and m as follows: k is less than 1, l is less than 0.06, m is less than 0.25, and the single batteries which meet the requirements that k is less than 1, l is less than 0.06, m is less than 0.25 and the discharge capacity Q is more than the rated capacity are screened out and marked as primary screening batteries;
s4, performing self-discharge consistency test on the primary screened battery, and calculating a capacity retention rate η 1 and a capacity recovery rate η 2;
s5, setting the preset ranges of η 1 and η 2 to be η 1 > 95 percent and η 2 > 96 percent, and screening η 1 > 95 percent and η 2 > 96 percent of single batteries to be qualified batteries.
In step S5, the method for testing self-discharge consistency includes the following steps:
a. carrying out constant-current first charging on the single battery with the current of 27A until the SOC reaches 50 percent, and recording the first charging capacity as Q1；
b. B, standing the battery charged for the first time in the step a at a high temperature of 45 ℃ for 7 days, cooling to normal temperature within 5 hours, performing constant-current first discharge with a current of 27A to a lower limit cut-off voltage, and recording the first discharge capacity as Q2；
c. And c, performing secondary charging on the battery discharged for the first time in the step b until the battery is fully charged, wherein the specific method for secondary charging comprises the following steps: the method comprises the steps of firstly, conducting constant current charging to the upper limit cut-off voltage with the current of 27A, then conducting constant voltage charging to the cut-off current of 0.05C, and then obtaining full charge;
d. c, discharging the battery charged for the second time in the step c to a lower limit cut-off voltage for the second time at a constant current of 27A, and recording the discharge capacity for the second time as Q3Calculating capacity retention and capacityAmount recovery rate, wherein capacity retention rate η 1Q2/Q1Capacity recovery ratio η 2Q3/Q。
The test results for 30 cells are shown in table 1:
table 1 test results of unit cells
According to the screening method described above, the batteries numbered 1, 4, 6, 8, 15, 19, 23 and 29 can be judged as defective batteries from the data in the table.
Welding qualified batteries numbered 2, 3, 5, 7 and 9 into a 5-combined module, and marking the 5-combined module as a No. 1 module; the qualified batteries numbered 10, 11, 12, and 13 and the unqualified battery numbered 1 were welded into a 5-pack and labeled as a # 2 module. Respectively carrying out charge-discharge circulation on the No. 1 module and the No. 2 module at the temperature of 25 +/-2 ℃ by using 135A current, wherein circulation curves respectively correspond to a curve 1# and a curve 2# in the graph 1; comparing the circulation curves of the No. 1 module and the No. 2 module, the screening method provided by the invention is verified, and the screening method provided by the invention can effectively improve the consistency of the parallel modules, thereby prolonging the circulation life of the parallel modules.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (8)
1. A screening method of lithium ion batteries is characterized by comprising the following steps:
s1, performing a plurality of charge-discharge cycles on a plurality of single batteries with rated capacity C at room temperature to obtain the discharge capacity Q, the median voltage U and the constant current charge ratio P of the single batteries, and calculating the average discharge capacity of all the single batteries
Mean discharge median voltage
Average constant current charge ratio
S2, calculating a screening coefficient k of the capacity of the single battery, a screening coefficient l of the median voltage and a screening coefficient m of the constant current charging ratio, wherein
S3, setting preset ranges of k, l and m, screening out single batteries with k, l and m values within the preset ranges and discharge capacity Q larger than rated capacity, and recording as primary screening batteries;
s4, performing self-discharge consistency test on the primary screened battery, and calculating a capacity retention rate η 1 and a capacity recovery rate η 2;
and S5, setting preset ranges of η 1 and η 2, and screening out the single batteries with the values of η 1 and η 2 within the preset ranges.
2. The screening method of lithium ion batteries according to claim 1, wherein the preset range of the capacity retention rate η 1 is η 1 > 95%, and the preset range of the capacity recovery rate η 2 is η 2 > 96%.
3. The method for screening lithium ion batteries according to any one of claims 1 or 2, wherein the number of charge and discharge cycles is 3 to 5 in step S1.
4. The screening method for lithium ion batteries according to any one of claims 1 to 3, wherein in the step S5, the specific method for the self-discharge consistency test comprises the following steps:
a. the single battery is charged for the first time with constant current until 50% SO is reachedC, first charge capacity is recorded as Q1；
b. B, placing the battery after the first charging in the step a at high temperature, then cooling to normal temperature, carrying out constant current first discharging to lower limit cut-off voltage, and recording the first discharge capacity as Q2；
c. C, charging the battery discharged for the first time in the step b for the second time until the battery is fully charged;
d. c, performing constant-current secondary discharge on the battery charged for the second time in the step c to reach a lower limit cut-off voltage, and recording the discharge capacity of the battery for the second time as Q3Calculating a capacity retention rate and a capacity recovery rate, wherein the capacity retention rate η 1 is Q2/Q1Capacity recovery ratio η 2Q3/Q。
5. The screening method for lithium ion batteries according to claim 4, wherein in the step b, the high temperature is set at 45-60 ℃ for 7 days.
6. The screening method of lithium ion batteries according to claim 4 or 5, wherein in the step b, the time for cooling to normal temperature is 5h to 10 h.
7. The screening method of lithium ion batteries according to any one of claims 4 to 6, wherein in the step c, the specific method of the second charging is as follows: the constant current is charged to the upper limit cut-off voltage, and then the constant voltage is charged to the cut-off current, namely the full charge is realized.
8. The screening method for lithium ion batteries according to any one of claims 1 to 7, wherein the charge-discharge cycle in step S1 and the self-discharge consistency test in step S4 use the same magnitude of charge current, which is 0.33C to 1C; the discharge current used was the same and was 0.33C-1C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010129255.3A CN111282853A (en) | 2020-02-28 | 2020-02-28 | Screening method of lithium ion battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010129255.3A CN111282853A (en) | 2020-02-28 | 2020-02-28 | Screening method of lithium ion battery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111282853A true CN111282853A (en) | 2020-06-16 |
Family
ID=71018113
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010129255.3A Pending CN111282853A (en) | 2020-02-28 | 2020-02-28 | Screening method of lithium ion battery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111282853A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113945753A (en) * | 2021-09-01 | 2022-01-18 | 力高(山东)新能源技术有限公司 | Method for judging battery cell voltage abnormity of battery pack |
| CN115308630A (en) * | 2022-09-29 | 2022-11-08 | 苏州琞能能源科技有限公司 | Attenuation analysis method for battery life |
| CN115524628A (en) * | 2022-10-11 | 2022-12-27 | 欣旺达电子股份有限公司 | Soft package lithium ion battery capacity fade failure analysis method and system |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5761072A (en) * | 1995-11-08 | 1998-06-02 | Ford Global Technologies, Inc. | Battery state of charge sensing system |
| CN104014491A (en) * | 2014-06-26 | 2014-09-03 | 武汉中原长江科技发展有限公司 | Screening method of parallel lithium ion batteries |
| CN104090239A (en) * | 2014-06-26 | 2014-10-08 | 武汉中原长江科技发展有限公司 | Series connection lithium ion battery screening method |
| CN106378317A (en) * | 2016-09-30 | 2017-02-08 | 上海空间电源研究所 | High-voltage high-power lithium ion battery pack monomer screening method and system |
| CN108363015A (en) * | 2018-01-31 | 2018-08-03 | 北京智行鸿远汽车有限公司 | A kind of screening technique of lithium ion battery consistency |
| CN109188288A (en) * | 2018-09-30 | 2019-01-11 | 江西安驰新能源科技有限公司 | A kind of power battery self discharge detection and stepping technique |
| CN110501649A (en) * | 2019-07-26 | 2019-11-26 | 苏州安靠电源有限公司 | A kind of lithium battery Conformance Assessment test method |
-
2020
- 2020-02-28 CN CN202010129255.3A patent/CN111282853A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5761072A (en) * | 1995-11-08 | 1998-06-02 | Ford Global Technologies, Inc. | Battery state of charge sensing system |
| CN104014491A (en) * | 2014-06-26 | 2014-09-03 | 武汉中原长江科技发展有限公司 | Screening method of parallel lithium ion batteries |
| CN104090239A (en) * | 2014-06-26 | 2014-10-08 | 武汉中原长江科技发展有限公司 | Series connection lithium ion battery screening method |
| CN106378317A (en) * | 2016-09-30 | 2017-02-08 | 上海空间电源研究所 | High-voltage high-power lithium ion battery pack monomer screening method and system |
| CN108363015A (en) * | 2018-01-31 | 2018-08-03 | 北京智行鸿远汽车有限公司 | A kind of screening technique of lithium ion battery consistency |
| CN109188288A (en) * | 2018-09-30 | 2019-01-11 | 江西安驰新能源科技有限公司 | A kind of power battery self discharge detection and stepping technique |
| CN110501649A (en) * | 2019-07-26 | 2019-11-26 | 苏州安靠电源有限公司 | A kind of lithium battery Conformance Assessment test method |
Non-Patent Citations (1)
| Title |
|---|
| 姜久春: "《电动汽车相关标准》", 30 April 2016 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113945753A (en) * | 2021-09-01 | 2022-01-18 | 力高(山东)新能源技术有限公司 | Method for judging battery cell voltage abnormity of battery pack |
| CN113945753B (en) * | 2021-09-01 | 2023-11-28 | 力高(山东)新能源技术有限公司 | Method for judging abnormal voltage of battery cell |
| CN115308630A (en) * | 2022-09-29 | 2022-11-08 | 苏州琞能能源科技有限公司 | Attenuation analysis method for battery life |
| CN115308630B (en) * | 2022-09-29 | 2023-03-03 | 苏州琞能能源科技有限公司 | Attenuation analysis method for battery life |
| CN115524628A (en) * | 2022-10-11 | 2022-12-27 | 欣旺达电子股份有限公司 | Soft package lithium ion battery capacity fade failure analysis method and system |
| CN115524628B (en) * | 2022-10-11 | 2023-07-18 | 欣旺达电子股份有限公司 | Soft package lithium ion battery capacity decay failure analysis method and system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103545567B (en) | A kind of method of quick sorting lithium ion battery | |
| CN104062594B (en) | Lithium-ion-power cell method for group matching | |
| WO2018209784A1 (en) | Lithium precipitation detection method for battery, battery management system, and battery system | |
| CN108051751B (en) | Lithium ion power battery sorting method and system | |
| CN112820963B (en) | Low-temperature charging method for lithium ion battery | |
| WO2021082341A1 (en) | Rapid grouping and repairing method for recycled batteries | |
| CN111458650B (en) | Method for estimating peak power of lithium ion power battery system | |
| CN111282853A (en) | Screening method of lithium ion battery | |
| CN108226806B (en) | Charge self-discharge detection method and battery detection device | |
| CN104950264A (en) | Method for testing self-discharge of lithium ion battery | |
| CN108390091A (en) | A kind of formation of Li-ion batteries aging partial volume technique | |
| CN107422265A (en) | A kind of detection method of cell uniformity | |
| CN104991197A (en) | Lithium iron phosphate lithium ion battery self-discharge test method | |
| CN112540297A (en) | Method for researching overcharge safety redundancy boundary of lithium ion battery | |
| Mars et al. | Comparison study of different dynamic battery model | |
| CN112786984A (en) | Stage charging method of lithium ion battery | |
| Wang et al. | Characteristic analysis of lithium titanate battery | |
| CN110865307B (en) | Battery module complementary energy detection method | |
| CN105244535B (en) | A kind of method for separating of lithium rechargeable battery | |
| CN101834325A (en) | Secondary battery pack | |
| Chen et al. | Performance of inconsistency in lithium-ion battery packs for battery energy storage systems | |
| CN111679219B (en) | Self-discharge screening method for lithium ion power battery | |
| Dutt | Life cycle analysis and recycling techniques of batteries used in renewable energy applications | |
| Dwipayana et al. | Status of Battery in Indonesia to Support Application of Solar PV with Energy Storage | |
| CN110639845A (en) | Method suitable for screening and matching upper-level lithium ion single 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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20200616 |