CN113675489A - Method for forming and screening bad cells - Google Patents

Method for forming and screening bad cells Download PDF

Info

Publication number
CN113675489A
CN113675489A CN202110746224.7A CN202110746224A CN113675489A CN 113675489 A CN113675489 A CN 113675489A CN 202110746224 A CN202110746224 A CN 202110746224A CN 113675489 A CN113675489 A CN 113675489A
Authority
CN
China
Prior art keywords
cells
charging
battery cell
voltage
formation
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
CN202110746224.7A
Other languages
Chinese (zh)
Inventor
张衡
陶胜
孟旭
田生伟
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.)
Ningbo Veken Battery Co ltd
Original Assignee
Ningbo Veken Battery 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 Ningbo Veken Battery Co ltd filed Critical Ningbo Veken Battery Co ltd
Priority to CN202110746224.7A priority Critical patent/CN113675489A/en
Publication of CN113675489A publication Critical patent/CN113675489A/en
Pending legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/42Methods or arrangements for servicing or maintenance of secondary cells or secondary half-cells
    • H01M10/44Methods for charging or discharging
    • H01M10/446Initial charging measures
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01MPROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00Secondary cells; Manufacture thereof
    • H01M10/04Construction or manufacture in general
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10Energy storage using batteries
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50Manufacturing or production processes characterised by the final manufactured product

Abstract

The invention belongs to the technical field of polymer batteries, and relates to a method for forming and screening bad cells. The method for screening the bad cells in the formation mode comprises the steps of charging the cells through current, judging whether the cells are abnormal or not by utilizing whether the voltage of the cells drops within a certain charging time, and in the formation charging process, performing the formation step charging according to currents with different multiplying powers, wherein the voltage drops; the screening method is rapid and accurate, is safe and simple to operate in formation equipment, is suitable for large-scale industrial production, improves the efficiency and greatly reduces the labor cost.

Description

Method for forming and screening bad cells
Technical Field
The invention belongs to the technical field of polymer batteries, and relates to a method for forming and screening bad cells.
Background
In the current manufacturing process of polymer battery cells, formation is a key process. The former process of formation is bad, for example moisture exceeds standard, inside short circuit, cladding are bad etc. are bad, if can't choose can influence electric core performance and safety, and the bad electric core of moisture flows out can lead to electric core capacity low, poor scheduling problem of circulation, and inside short circuit and the bad electric core of cladding flow out can lead to electric core self discharge big, and the formation in-process can take place the burning, causes irrecoverable economic loss.
The polymer battery cell with the undesirable problems of excessive moisture, internal short circuit, poor coating and the like is picked out before the formation process, so that the performance and safety of the battery cell are prevented from being influenced, and the problem of irrecoverable economic loss caused by combustion in the formation process is avoided.
At present, the conventional screening is poor in procedure identification after formation, a capacity-grading procedure screens out an electric core with excessive moisture content through capacity and gas production conditions, an OCV procedure screens out an internal short circuit and a coated poor electric core through an aged voltage drop level, the problem of poor electric core identification is delayed, a combustion safety problem possibly occurs before screening, the screening accuracy is reduced due to the influence of equipment, an aging process, personnel and environment, and the poor electric core flows out to a client, so that a method for forming and screening the poor electric core is needed to be provided, and the problem is solved.
Disclosure of Invention
The invention aims to provide a method for forming and screening bad cells with high efficiency and good safety performance aiming at the problems of the prior art of polymer cells.
The purpose of the invention can be realized by the following technical scheme: a method of formation screening for defective cells, the method comprising the steps of:
s1, cell loading: placing the battery cell with good electrolyte infiltration into formation equipment, and then clamping the battery cell;
s2, formation charging: step charging is carried out on the battery cell by current;
s3, checking: after step charging, rejecting unqualified cells according to voltage variation;
s4, selecting a bad battery cell: and (5) finishing formation, and selecting the rejected unqualified battery cell as a bad battery cell.
The invention charges the battery cell through current, judges whether the battery cell is abnormal by using whether the voltage of the battery cell drops within a certain charging time, intercepts, rejects and discards bad battery cells, and screens out battery cells with over-standard moisture, internal short circuit and bad cladding.
In the method for forming and screening the bad cells, the clamping pressure in step S1 is 0.5-2.0 MPa.
In the method for screening defective cells, the step charging includes two-stage or multi-stage charging. The invention is beneficial to the battery cell to form a good SEI film through a step charging mode, improves the cycle performance and can greatly shorten the formation time.
In the method for forming and screening the bad cells, the charging current in step S2 is 0.1-2.0C.
In the method for forming and screening the bad cells, the cell voltage after step charging in step S2 is 1.0-4.45V.
In the method for forming and screening the bad cells, the step S2 is performed by a step charging method, wherein the first-stage current is 0.1-0.5C, and the second-stage current is 0.5-2.0C.
In the method for forming and screening the bad cells, the cell voltage after the first stage of the step charging is 1.0-3.5V, and the cell voltage after the second stage of the step charging is 3.5-4.45V. When the voltage of the first stage is 1.0-3.5V, the moisture exceeding battery cell is reduced in the voltage stage during charging, so that the moisture exceeding battery cell can be quickly screened out. When the voltage of the second stage is 3.5-4.45V, the electric core with internal short circuit and poor coating begins to self-discharge when being charged to more than 3.5V, and the voltage drops, so that the electric core with internal short circuit and poor coating can be quickly screened out.
In the method for forming and screening the bad cells, the cells removed in the first stage of the step charging are cells with voltage instantly reduced by 0.1-3500mV, continuously reduced for more than 2-10 times and accumulated reduced times for more than 2-10 times.
In the method for forming and screening the bad cells, the cells rejected in the second stage of step charging are cells with voltage instantly reduced by 0.1-4450mV, continuously reduced for more than 2-10 times and accumulated reduced times for more than 2-10 times.
In the method for forming and screening the bad cells, the forming equipment has a function of rejecting the cells.
Preferably, the formation equipment is vertical or horizontal.
In the method for forming and screening the bad cells, one of the instantaneous cell voltage drop value, the continuous drop times and the accumulated drop times exceeds the standard, namely, the cells are intercepted and removed.
In the method for forming and screening the bad cells, the bad cells comprise one or more of excessive moisture, internal short circuit and poor coating.
Compared with the prior art, the invention has the following beneficial effects: the method for screening the bad cells in the formation mode comprises the steps of charging the cells through current, judging whether the cells are abnormal or not by utilizing whether the voltage of the cells drops within a certain charging time, and in the formation charging process, performing the formation step charging according to currents with different multiplying powers, wherein the voltage drops; the screening method is rapid and accurate, is safe and simple to operate in formation equipment, is suitable for large-scale industrial production, improves the efficiency and greatly reduces the labor cost.
Detailed Description
The following are specific examples of the present invention and further describe the technical solutions of the present invention, but the present invention is not limited to these examples.
Example 1:
s1, soaking a good battery cell with electrolyte after injection with the model number of thickness multiplied by width multiplied by height multiplied by 4.5mm multiplied by 60mm multiplied by 80mm, safely putting the battery cell into formation equipment, ensuring that a battery cell main body is not exposed, effectively contacting a lug with a charging circuit board, using vertical equipment for formation, and enabling equipment software to have the function of removing bad battery cells;
s2, starting equipment to clamp the battery cell, and clamping the battery cell according to the pressure of 1.0 MPa;
s3, charging the battery cell by the formation according to different multiplying power current steps, and adopting two-step charging;
s4, after the flow is sent in step S3When the first-stage current is 0.1C, the cell voltage begins to increase, and the cell voltage V is detected1When the voltage is 1.0-3.5V, the voltage V is screened1Instantly dropping the battery cell of 0.1-3500mV, stopping charging, continuously dropping for more than 2-10 times, accumulating for more than 2-10 times, and removing the battery cell with excessive water, internal short circuit and poor coating;
s5, continuously increasing the cell voltage remained in the step S4, wherein the current in the second stage is 2.0C, and detecting the cell voltage V2When the voltage is 3.5-4.45V, the voltage V is screened2The battery cell which is instantly dropped by 0.1-4450mV drops for more than 2-10 times continuously, the accumulated dropping times exceed 2-10 times, the charging is stopped, and the battery cell with internal short circuit and poor coating is removed;
and S6, selecting the removed battery cells according to the prompt after the formation is finished.
Example 2:
s1, soaking a good battery cell with electrolyte after injection with the model number of thickness multiplied by width multiplied by height multiplied by 4.5mm multiplied by 60mm multiplied by 80mm, safely putting the battery cell into formation equipment, ensuring that a battery cell main body is not exposed, effectively contacting a lug with a charging circuit board, using horizontal equipment for formation, and enabling equipment software to have the function of removing bad battery cells;
s2, starting equipment to clamp the battery cell, and clamping the battery cell according to the pressure of 0.5 MPa;
s3, charging the battery cell by the formation according to different multiplying power current steps, and charging in two steps;
s4, after the flow is sent in the step S3, the current in the first stage is 0.1C, the cell voltage starts to increase, and the cell voltage V is detected1When the voltage is 1.0-3.5V, screening out the battery cell with the voltage V1 instantly reduced by 0.1-3500mV, stopping charging, continuously reducing for more than 2-10 times, accumulating for more than 2-10 times of reduction, and removing the battery cells with overproof water, internal short circuit and poor coating;
s5, continuously increasing the cell voltage remained in the step S4, wherein the current in the second stage is 0.5C, and detecting the cell voltage V2When the voltage is 3.5-4.45V, the voltage V is screened2The battery cell which is instantly dropped by 0.1-4450mV drops for more than 2-10 times continuously, the accumulated dropping times exceed 2-10 times, the charging is stopped, and the battery cell with internal short circuit and poor coating is removed;
and S6, selecting the removed battery cells according to the prompt after the formation is finished.
Example 3:
s1, soaking a good battery cell with electrolyte after injection with the model number of thickness multiplied by width multiplied by height multiplied by 4.5mm multiplied by 60mm multiplied by 80mm, safely putting the battery cell into formation equipment, ensuring that a battery cell main body is not exposed, effectively contacting a lug with a charging circuit board, using vertical equipment for formation, and enabling equipment software to have the function of removing bad battery cells;
s2, starting equipment to clamp the battery cell, and clamping the battery cell according to the pressure of 2.0 MPa;
s3, charging the battery cell by the formation according to different multiplying power current steps, and charging in two steps;
s4, after the flow is sent in the step S3, the current in the first stage is 0.5C, the cell voltage starts to increase, and the cell voltage V is detected1When the voltage is 1.0-3.5V, the voltage V is screened1Instantly dropping the battery cell of 0.1-3500mV, stopping charging, continuously dropping for more than 2-10 times, accumulating for more than 2-10 times, and removing the battery cell with excessive water, internal short circuit and poor coating;
s5, continuously increasing the cell voltage remained in the step S4, wherein the current in the second stage is 2.0C, and detecting the cell voltage V2When the voltage is 3.5-4.45V, the voltage V is screened2The battery cell which is instantly dropped by 0.1-4450mV drops for more than 2-10 times continuously, the accumulated dropping times exceed 2-10 times, the charging is stopped, and the battery cell with internal short circuit and poor coating is removed;
and S6, selecting the removed battery cells according to the prompt after the formation is finished.
Example 4:
s1, soaking a good battery cell with electrolyte after injection with the model number of thickness multiplied by width multiplied by height multiplied by 5.5mm multiplied by 65mm multiplied by 85mm, safely putting the battery cell into formation equipment, ensuring that a battery cell main body is not exposed, effectively contacting a lug with a charging circuit board, using horizontal equipment for formation, and enabling equipment software to have the function of removing a bad battery cell;
s2, starting equipment to clamp the battery cell, and clamping the battery cell according to the pressure of 2.0 MPa;
s3, charging the battery cell by the formation according to different multiplying power current steps, and adopting three-step charging;
s4, after the flow is sent in the step S3, the current in the first stage is 0.2C, the cell voltage starts to increase, and the cell voltage V is detected1When the voltage is 1.0-3.5V, the voltage V is screened1Instantly dropping the battery cell of 0.1-3500mV, stopping charging, continuously dropping for more than 2-10 times, accumulating for more than 2-10 times, and removing the battery cell with excessive water, internal short circuit and poor coating;
s5, continuously increasing the cell voltage remained in the step S4, wherein the current in the second stage is 0.7C, and detecting the cell voltage V2When the voltage is 3.5-4.0V, the voltage V is screened2The battery cell which drops 0.1-4000mV instantly drops for more than 2-10 times continuously, the accumulated dropping times exceed 2-10 times, the charging is stopped, and the battery cell with internal short circuit and poor coating is removed;
s6, continuously increasing the cell voltage remained in the step S5, wherein the current in the third stage is 1.5C, and detecting the cell voltage V3When the voltage is 4.0-4.45V, the voltage V is screened3The battery cell which is instantly dropped by 0.1-4450mV drops for more than 2-10 times continuously, the accumulated dropping times exceed 2-10 times, the charging is stopped, and the battery cell with internal short circuit and poor coating is removed;
and S7, selecting the removed battery cells according to the prompt after the formation is finished.
Comparative example 1:
the only difference from example 1 is that comparative example 1 did not screen cells for defective cells.
Comparative example 2:
the only difference from example 1 is that comparative example 2 was used to charge the cell once, the current was 0.1C, the cell voltage started to increase, and the cell voltage was measured to be 2.5V.
192 cells, 50 of which were defective, were prepared and tested according to the screening methods of examples 1 to 4 and comparative examples 1 to 2, respectively.
Table 1: cell detection results after rapid screening of examples 1-4 and comparative examples 1-2
Figure BDA0003142837200000071
According to the method for screening the bad cells, the cells are charged through current, whether the cells are abnormal or not is judged by whether the cell voltage drops within a certain charging time, in the formation charging process, the formation is charged according to current steps with different multiplying powers, the voltage drops, the formation process is immediately stopped through setting voltage drop protection when the voltage drops in the charging process, the charging is not carried out, the bad cells are removed and scrapped, and therefore the effect of removing the unqualified cells with the moisture exceeding the standard, the internal short circuit and the bad coating is achieved.
The technical scope of the invention claimed by the embodiments of the present application is not exhaustive, and new technical solutions formed by equivalent replacement of single or multiple technical features in the technical solutions of the embodiments are also within the scope of the invention claimed by the present application; in all the embodiments of the present invention, which are listed or not listed, each parameter in the same embodiment only represents an example (i.e., a feasible embodiment) of the technical solution, and there is no strict matching and limiting relationship between the parameters, wherein the parameters may be replaced with each other without departing from the axiom and the requirements of the present invention, unless otherwise specified.
The technical means disclosed by the scheme of the invention are not limited to the technical means disclosed by the technical means, and the technical scheme also comprises the technical scheme formed by any combination of the technical characteristics. While the foregoing is directed to embodiments of the present invention, it will be appreciated by those skilled in the art that various changes may be made in the embodiments without departing from the principles of the invention, and that such changes and modifications are intended to be included within the scope of the invention.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims (10)

1. A method for forming and screening poor battery cells is characterized by comprising the following steps:
s1, cell loading: placing the battery cell with good electrolyte infiltration into formation equipment, and then clamping the battery cell;
s2, formation charging: step charging is carried out on the battery cell by current;
s3, checking: after step charging, rejecting unqualified cells according to voltage variation;
s4, selecting a bad battery cell: and (5) finishing formation, and selecting the rejected unqualified battery cell as a bad battery cell.
2. The method of claim 1, wherein the step charging comprises two or more charging.
3. The method for forming the screened defective battery cell as claimed in claim 1, wherein the step charging current of step S2 is 0.01-2.0C.
4. The method of claim 2 or 3, wherein the cell voltage after step charging in step S2 is 1.0-4.45V.
5. The method of claim 2, wherein the step charging in step S2 is performed at a first stage current of 0.1-0.5C and a second stage current of 0.5-2.0C.
6. The method of claim 5, wherein the cell voltage after the first stage of step charging is 1.0-3.5V, and the cell voltage after the second stage of step charging is 3.5-4.45V.
7. The method of claim 5, wherein the cells removed in the first step of step charging are cells with voltage drop of 0.1-3500mV instantaneously, continuous drop of more than 2-10 times, and cumulative drop of more than 2-10 times.
8. The method of claim 5, wherein the cells rejected in the second step charging stage are cells with instantaneous voltage drop of 0.1-4450mV, continuous voltage drop of more than 2-10 times, and cumulative voltage drop of more than 2-10 times.
9. The method of claim 1, wherein the formation equipment has a function of rejecting the cells.
10. The method of claim 1, wherein the defective cells comprise one or more of out-of-specification moisture, internal short circuits, and poor encapsulation.
CN202110746224.7A 2021-07-01 2021-07-01 Method for forming and screening bad cells Pending CN113675489A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110746224.7A CN113675489A (en) 2021-07-01 2021-07-01 Method for forming and screening bad cells

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110746224.7A CN113675489A (en) 2021-07-01 2021-07-01 Method for forming and screening bad cells

Publications (1)

Publication Number Publication Date
CN113675489A true CN113675489A (en) 2021-11-19

Family

ID=78538309

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110746224.7A Pending CN113675489A (en) 2021-07-01 2021-07-01 Method for forming and screening bad cells

Country Status (1)

Country Link
CN (1) CN113675489A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023193268A1 (en) * 2022-04-08 2023-10-12 宁德时代新能源科技股份有限公司 Battery cell short circuit identification method and apparatus, bms, battery pack, device and medium
WO2023201532A1 (en) * 2022-04-19 2023-10-26 宁德时代新能源科技股份有限公司 Abnormal battery cell identification method and apparatus, electronic device, and storage medium

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002216851A (en) * 2001-01-15 2002-08-02 Mitsubishi Cable Ind Ltd Manufacturing method of lithium ion secondary cell
CN1508901A (en) * 2002-12-18 2004-06-30 北京有色金属研究总院 Method for scparating secodary cell
JP2015185485A (en) * 2014-03-26 2015-10-22 オートモーティブエナジーサプライ株式会社 Method for self-discharge inspection of nonaqueous electrolyte secondary batteries
CN105583170A (en) * 2016-01-28 2016-05-18 珠海光宇电池有限公司 Method for screening lithium ion batteries
JP2017126539A (en) * 2016-01-15 2017-07-20 トヨタ自動車株式会社 Method for manufacturing secondary battery
CN108020788A (en) * 2017-10-27 2018-05-11 合肥国轩高科动力能源有限公司 A kind of lithium ion battery internal resistance rapid screening method
CN109975716A (en) * 2019-03-07 2019-07-05 天津力神电池股份有限公司 A kind of detection method of lithium ion battery internal resistance fluctuation

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002216851A (en) * 2001-01-15 2002-08-02 Mitsubishi Cable Ind Ltd Manufacturing method of lithium ion secondary cell
CN1508901A (en) * 2002-12-18 2004-06-30 北京有色金属研究总院 Method for scparating secodary cell
JP2015185485A (en) * 2014-03-26 2015-10-22 オートモーティブエナジーサプライ株式会社 Method for self-discharge inspection of nonaqueous electrolyte secondary batteries
JP2017126539A (en) * 2016-01-15 2017-07-20 トヨタ自動車株式会社 Method for manufacturing secondary battery
CN105583170A (en) * 2016-01-28 2016-05-18 珠海光宇电池有限公司 Method for screening lithium ion batteries
CN108020788A (en) * 2017-10-27 2018-05-11 合肥国轩高科动力能源有限公司 A kind of lithium ion battery internal resistance rapid screening method
CN109975716A (en) * 2019-03-07 2019-07-05 天津力神电池股份有限公司 A kind of detection method of lithium ion battery internal resistance fluctuation

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023193268A1 (en) * 2022-04-08 2023-10-12 宁德时代新能源科技股份有限公司 Battery cell short circuit identification method and apparatus, bms, battery pack, device and medium
WO2023201532A1 (en) * 2022-04-19 2023-10-26 宁德时代新能源科技股份有限公司 Abnormal battery cell identification method and apparatus, electronic device, and storage medium

Similar Documents

Publication Publication Date Title
CN104014491B (en) A kind of screening technique of lithium ion battery in parallel
CN113675489A (en) Method for forming and screening bad cells
CN110376530B (en) Device and method for detecting short circuit in battery
CN103579700B (en) A kind of lithium ion battery sorting method for group matching
CN103611692A (en) Lithium iron phosphate power battery consistency matching screening method
CN106154173A (en) A kind of self discharge screening technique of the cheapest secondary cell easily
CN107617582B (en) Echelon utilization screening and grouping method for power cells
CN112698233B (en) False welding detection method and system for lithium ion power battery pack
CN105680108A (en) Method for screening lithium ion batteries
CN105070963A (en) Method for optimizing high-magnification power lithium ion battery SEI film
CN110045290B (en) Nondestructive testing method for potential short circuit defects in lithium ion storage battery
CN109450027A (en) Lithium ion battery equalization methods
CN105548911A (en) Method for lowering influence of reverse current on battery voltage-resistant insulation test
CN113484778A (en) Method for rapidly screening self-discharge of battery
CN112798972B (en) Method for rapidly evaluating consistency of lithium battery winding cores
CN110911757A (en) Safe capacity grading method for ternary lithium battery
CN106249164A (en) The detection method that a kind of quick judgement lead battery list only falls behind
CN111751738A (en) Process for detecting fragment cracking or tab cold welding of lithium ion battery pole
CN106025404A (en) Internal short circuit warning detection method for lithium ion rechargeable batteries
CN113118056A (en) Lithium battery echelon utilization screening method
CN108380515A (en) A kind of power battery low pressure screening technique
CN110707387A (en) Self-discharge screening method for lithium iron phosphate core
CN110102515B (en) Screening method of lithium ion battery cell based on thermal imager
CN117019670A (en) Screening method of echelon batteries
CN109239606B (en) Lithium ion battery pre-formation negative pressure failure detection method

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