CN110672704A - Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film - Google Patents

Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film Download PDF

Info

Publication number
CN110672704A
CN110672704A CN201910856052.1A CN201910856052A CN110672704A CN 110672704 A CN110672704 A CN 110672704A CN 201910856052 A CN201910856052 A CN 201910856052A CN 110672704 A CN110672704 A CN 110672704A
Authority
CN
China
Prior art keywords
plastic film
aluminum
lithium ion
soft package
ion battery
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
CN201910856052.1A
Other languages
Chinese (zh)
Inventor
李良彬
李仁华
戈志敏
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.)
Dongguan Gan Feng Electronics Co Ltd
Original Assignee
Dongguan Gan Feng Electronics 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 Dongguan Gan Feng Electronics Co Ltd filed Critical Dongguan Gan Feng Electronics Co Ltd
Priority to CN201910856052.1A priority Critical patent/CN110672704A/en
Publication of CN110672704A publication Critical patent/CN110672704A/en
Pending legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/60Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrostatic variables, e.g. electrographic flaw testing
    • G01N27/61Investigating the presence of flaws
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N27/00Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
    • G01N27/92Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating breakdown voltage
    • 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]
    • G01R31/385Arrangements for measuring battery or accumulator variables

Landscapes

  • Chemical & Material Sciences (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Electrochemistry (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Connection Of Batteries Or Terminals (AREA)
  • Sealing Battery Cases Or Jackets (AREA)

Abstract

The invention provides an identification method for rapidly judging the damage of an aluminum-plastic film of a soft package lithium ion battery, which is characterized in that a positive electrode tab is directly welded with the aluminum-plastic film to be connected with an aluminum layer of an intermediate layer of the aluminum-plastic film, if the aluminum-plastic film is damaged, the internal micro short circuit of a battery cell can be caused, so that current passes through abnormal heat sealing areas, the internal resistance of the battery is increased, the voltage drop in unit time exceeds a specified measurement range, and the yield condition of the battery cell is rapidly detected.

Description

Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film
Technical Field
The invention relates to the technical field of lithium ion battery detection, in particular to an identification method for rapidly judging the damage of an aluminum plastic film of a soft package lithium ion battery.
Background
The aluminum-plastic film is a composite material formed by an outer protective layer, a middle aluminum layer and an inner heat sealing layer, and the layers are pressed and bonded through an adhesive. The aluminum plastic film is a key material for packaging the battery core of the flexible package lithium battery, the single battery is assembled and then sealed by the aluminum plastic film to form the battery, and the aluminum plastic film plays a role in protecting contents.
The internal corrosion of the aluminum-plastic film can cause short circuit risk, the essence of electrochemical corrosion is that the aluminum-plastic film PP is damaged, and then the aluminum film is corroded by electrolyte, so that the aluminum-plastic film in the area is damaged by corrosion, and the aluminum layer is electrified to be at a lower potential, so that the lithium-embedded alloy is formed. Finally causing the safety accident of liquid leakage.
Chinese patent application publication No. CN103048376A, published as 2013.04.17, discloses a method for detecting corrosion in a flexible package lithium ion battery, which comprises the steps of measuring the voltage between the positive electrode and the negative electrode of the lithium ion battery and the voltage between the positive electrode tab and an aluminum-plastic composite film by using a voltmeter, comparing the measured voltages, and if the voltage between the positive electrode tab and the aluminum layer is equal to or slightly less than the theoretical voltage value of the battery, the aluminum layer in the aluminum-plastic film is necessarily subjected to internal corrosion; or the resistance between the positive electrode lug and the aluminum layer of the aluminum plastic film is measured by a multimeter more simply, and if the measured resistance value is less than 100 omega, internal corrosion occurs. The method has the disadvantages that the method needs to be carried out in a full-charge state of the finished battery, the battery can be detected only by laying aside for more than one day, the heat sealing effect of the aluminum plastic film cannot be rapidly detected, and the detection period is long. In addition, the method has certain uncertainty because the electrolyte is required to be present at the damaged position of the aluminum-plastic film to measure the voltage difference. The distribution of the electrolyte in the aluminum-plastic film has uncertainty, so the method has the possibility of missing detection.
The application publication No. CN104330710A discloses a method for rapidly judging poor insulation of a soft package lithium ion battery aluminum-plastic film, wherein a probe is inserted into any edge sealing of the soft package lithium ion battery to be in contact with an aluminum layer of the aluminum-plastic film, and the probe and a positive lug or a negative lug of the soft package lithium ion battery are respectively connected with two poles of an adjustable voltage direct current power supply through a lead, wherein the voltage of the adjustable voltage direct current power supply is more than or equal to 400V; (2) and starting a power supply, if the liquid leakage, the breakdown or the smoke phenomenon occurs in the edge sealing of the soft package lithium ion battery, indicating that the aluminum-plastic film at the position of the edge sealing is poor in insulation, and if the liquid leakage, the breakdown or the smoke phenomenon does not occur in the edge sealing of the soft package lithium ion battery, indicating that the aluminum-plastic film at the edge sealing of the soft package lithium ion battery is good in insulation. The method has the disadvantages that the single detection speed is low, so that the period is long when a large number of electric cores are detected, the electric core test operation needs proficiency, and automatic detection cannot be realized.
Disclosure of Invention
The invention aims to solve the problems so as to meet the requirement of rapidly and safely judging whether the battery cell is short-circuited in actual production. The following technical scheme is adopted:
an identification method for rapidly judging the damage of a soft package lithium ion battery aluminum plastic film comprises the following steps:
s1, welding: after the battery cell is packaged, welding a positive electrode lug and an aluminum-plastic film to enable the positive electrode lug to be in contact with a middle aluminum layer of the aluminum-plastic film;
s2, sealing: sealing the welding position of the battery cell after welding is finished;
s3, testing: performing a current test or an OCV test on the battery cell processed in step S2;
s4, judgment: checking whether the current or the voltage drop of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if the current appears, or the voltage drop exceeds the normal range, or the appearance of the battery cell is abnormal, the inside of the battery cell is corroded, and the aluminum-plastic film is damaged.
The working principle of the invention is as follows: the aluminium-plastic film takes place the damage, can cause the middle aluminium lamination of negative pole utmost point ear and aluminium-plastic film to switch on, forms little electron channel, and anodal utmost point ear switches on through the welding with the aluminium-plastic film and forms electron channel, therefore the anodal of lithium cell can link to each other with the negative pole reality and form local little short circuit. The reaction equation is as follows: al + Li++e-LiAl. The self-discharge phenomenon can occur in the lithium battery core, the internal resistance of the battery core is increased, and the voltage is reduced. And carrying out current or OCV test on the welded battery cell, and judging whether the inside of the battery cell is corroded or not and whether the aluminum plastic film is damaged or not by testing whether current passes between the positive electrode and the negative electrode or not or whether the voltage drop of the battery cell exceeds a normal range. If the battery core is abnormal in the testing process, the properties are changed, and the aluminum plastic film is damaged.
The method disclosed by the invention is simple in principle and operation, has no requirement on the electric quantity state of the battery cell, is short in detection time, and can be used for quickly and conveniently detecting whether the aluminum plastic film is damaged.
Further, in step S1, the outer protection layer and the inner heat seal layer of the aluminum-plastic film are broken through by welding to expose the intermediate aluminum layer, and then the positive electrode tab is in welding contact with the intermediate aluminum layer of the aluminum-plastic film to form an electronic channel.
Furthermore, the welding in step S1 adopts laser welding, which has high speed, large depth, small deformation and high precision.
Further, the power density of the laser welding is in the range of 104~106W/cm2
Further, in the step S2, the sealing process is performed by dropping conductive oil at the welding position of the battery core, and the conductive oil plays two roles, namely, conducting the positive electrode tab and the aluminum layer, and sealing and isolating the welding position of the positive electrode tab from air.
Further, the conductive oil is conductive silver oil, conductive copper oil, conductive nickel oil or conductive silver copper oil.
Further, the OCV test in step S3 specifically includes: respectively connecting the positive electrode tab and the negative electrode tab of the soft package lithium ion battery with two electrodes of a voltage testing device through leads, measuring the voltage OCV between the positive electrode and the negative electrode, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1)。
Further, the step S4 of exceeding the normal range by the voltage drop of the battery cell specifically includes: the voltage drop K of two voltage tests is more than 0.05 mV/h.
Further, the current test in step S3 specifically includes: and respectively connecting the positive electrode lug and the negative electrode lug of the soft package lithium ion battery with two electrodes of a current testing device through leads, and measuring the current between the positive electrode and the negative electrode.
Further, the step S3 is to determine that the battery cell appearance is abnormal specifically: the edge sealing of the soft package lithium ion battery has the phenomena of liquid leakage, breakdown or smoking.
The invention can obtain the following beneficial effects:
1. according to the invention, the positive electrode tab is welded with the aluminum-plastic film, the state judgment of the aluminum-plastic film is converted into the voltage drop of the battery in unit time for judgment by measuring the voltage drop between the positive electrode and the negative electrode or measuring whether current passes between the positive electrode and the negative electrode, the concept is novel, and the aluminum-plastic film of the soft package lithium battery can be rapidly inspected for damage or not, so that the mass production is realized.
2. The method has the advantages of simple principle and convenient operation, can conveniently realize the detection of the corrosion in the lithium ion battery, and provides a good technical basis for improving the quality of the battery.
3. The invention can detect the battery at any time without detecting the battery in a full-charge state, and has wide application range.
4. The invention is a non-destructive detection method, which can not cause damage to the normal use of the battery and can not influence the use performance of the battery.
5. The detection method can detect the unqualified batteries on the production line in time, and prevent the unqualified products from flowing into the market.
Drawings
Fig. 1 is a schematic diagram of a front structure of a battery cell according to the present invention;
fig. 2 is a schematic diagram of a cell welding structure according to the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
According to the soft package lithium ion battery provided by the embodiment of the invention, the anode tab is made of an Al material, the cathode tab is made of a Ni material, the outer protection layer of the aluminum plastic film is made of a nylon material, and the inner heat sealing layer is made of a PP (polypropylene) material.
Example 1:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, welding a positive electrode lug and an aluminum-plastic film to enable the positive electrode lug to be in contact with a middle aluminum layer of the aluminum-plastic film;
s2, sealing: sealing the welding position of the battery cell after welding is finished;
s3, testing: performing current test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a direct current ammeter through leads, and measuring the current between the positive electrode and the negative electrode;
s4, judgment: checking whether current appears or not, and checking whether the appearance of the battery cell is abnormal or not; if the direct current ammeter has no indication, the aluminum-plastic film is complete, and the electrical core is well insulated; if the direct current ammeter shows numbers or the appearance of the battery cell is abnormal, the inside of the battery cell is corroded, and the aluminum-plastic film is damaged.
Example 2:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the position of the positive electrode tab and the position of the aluminum-plastic film, an outer protection layer and an inner heat sealing layer of the aluminum-plastic film are broken through laser, so that an intermediate aluminum layer is exposed, and the positive electrode tab is in welding contact with the intermediate aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, dripping conductive copper oil at the welding position of the battery cell to isolate air at the welding position of the positive electrode lug, and simultaneously conducting the positive electrode lug and the aluminum layer to play a role in conducting electricity;
s3, testing: performing current test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through leads, and measuring the current between the positive electrode and the negative electrode at a direct current gear;
s4, judgment: checking whether current appears or not, if the multimeter has no registration, indicating that the aluminum plastic film is complete and the electrical core is well insulated; if the number indicating is carried out by the universal meter, or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery core is corroded, and the aluminum plastic film is damaged.
Example 3:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the positive electrode lug and the aluminum plastic film, and the power density of the laser welding is 104W/cm2The outer protective layer and the inner heat-sealing layer of the aluminum-plastic film are broken down through laser to expose the middle aluminum layer, so that the positive electrode tab is in welding contact with the middle aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, the conductive silver oil is dropped at the welding position of the battery cell, so that the welding position of the positive electrode lug is isolated from air, and the positive electrode lug is conducted with the aluminum layer to play a role in conducting electricity;
s3, testing: performing current test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through leads, and measuring the current between the positive electrode and the negative electrode at a direct current gear;
s4, judgment: checking whether current appears or not, if the multimeter has no registration, indicating that the aluminum plastic film is complete and the electrical core is well insulated; if the number indicating is carried out by the universal meter, or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery core is corroded, and the aluminum plastic film is damaged.
Example 4:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the position of the positive electrode tab and the position of the aluminum-plastic film, an outer protection layer and an inner heat sealing layer of the aluminum-plastic film are broken through laser, so that an intermediate aluminum layer is exposed, and the positive electrode tab is in welding contact with the intermediate aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, dripping conductive copper oil at the welding position of the battery cell to isolate air at the welding position of the positive electrode lug, and simultaneously conducting the positive electrode lug and the aluminum layer to play a role in conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting the positive electrode tab and the negative electrode tab of the soft package lithium ion battery with two electrodes of a direct current voltmeter through leads, measuring the voltage OCV between the positive electrode and the negative electrode, and measuring the voltage OCV at the time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=2h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and if the voltage drop K is less than or equal to 0.05mV/h, indicating that the aluminum-plastic film is complete and the battery cell is well insulated; and if K is more than 0.05mV/h, the inside of the battery cell is corroded, and the aluminum-plastic film is damaged.
Example 5:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the position of the positive electrode tab and the position of the aluminum-plastic film, an outer protection layer and an inner heat sealing layer of the aluminum-plastic film are broken through laser, so that an intermediate aluminum layer is exposed, and the positive electrode tab is in welding contact with the intermediate aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, the conductive silver oil is dropped at the welding position of the battery cell, so that the welding position of the positive electrode lug is isolated from air, and the positive electrode lug is conducted with the aluminum layer to play a role in conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through a lead, measuring voltage OCV between the positive electrode and the negative electrode at a direct current voltage gear, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=5h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if K is less than or equal to 0.05mV/h or the appearance of the battery cell is good and has no abnormity, the aluminum-plastic film is complete and the battery cell is good in insulation; if K is more than 0.05mV/h or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery cell is corroded, and the aluminum plastic film is damaged.
Example 6:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the positive electrode lug and the aluminum plastic film, and the power density of the laser welding is within the range of 2 multiplied by 104W/cm2The outer protective layer and the inner heat-sealing layer of the aluminum-plastic film are broken down through laser to expose the middle aluminum layer, so that the positive electrode tab and the middle aluminum layer of the aluminum-plastic film are welded together;
s2, sealing: after welding, dripping conductive nickel oil at the welding position of the battery cell to isolate air at the welding position of the positive electrode lug, and simultaneously conducting the positive electrode lug and the aluminum layer to play a role of conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through a lead, measuring voltage OCV between the positive electrode and the negative electrode at a direct current voltage gear, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=10h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if K is less than or equal to 0.05mV/h or the appearance of the battery cell is good and has no abnormity, the aluminum-plastic film is complete and the battery cell is good in insulation; if K is more than 0.05mV/h or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery cell is corroded, and the aluminum plastic film is damaged.
Example 7:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the positive electrode lug and the aluminum plastic film, and the power density of the laser welding is within the range of 5 multiplied by 104W/cm2The outer protective layer and the inner heat-sealing layer of the aluminum-plastic film are broken down through laser to expose the middle aluminum layer, so that the positive electrode tab is in welding contact with the middle aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, dripping conductive silver and copper oil at the welding position of the battery cell, sealing and isolating the welding position of the positive electrode lug from air, and conducting the positive electrode lug and the aluminum layer to play a role in conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through a lead, measuring voltage OCV between the positive electrode and the negative electrode at a direct current voltage gear, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=16h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if K is less than or equal to 0.05mV/h or the appearance of the battery cell is good and has no abnormity, the aluminum-plastic film is complete and the battery cell is good in insulation; if K is more than 0.05mV/h or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery cell is corroded, and the aluminum plastic film is damaged.
Example 8:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the positive electrode lug and the aluminum plastic film, and the power density of the laser welding is within the range of 105W/cm2The outer protective layer and the inner heat-sealing layer of the aluminum-plastic film are broken down through laser to expose the middle aluminum layer, so that the positive electrode tab is in welding contact with the middle aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, dripping conductive silver oil at the welding position of the battery cell, isolating the welding position of the positive electrode lug from air, sealing, and conducting the positive electrode lug and the aluminum layer to play a role in conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through a lead, measuring voltage OCV between the positive electrode and the negative electrode at a direct current voltage gear, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=24h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if K is less than or equal to 0.05mV/h or the appearance of the battery cell is good and has no abnormity, the aluminum-plastic film is complete and the battery cell is good in insulation; if K is more than 0.05mV/h or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery cell is corroded, and the aluminum plastic film is damaged.
Example 9:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the positive electrode lug and the aluminum plastic film, and the power density of the laser welding is within the range of 3 multiplied by 105W/cm2The outer protective layer and the inner heat-sealing layer of the aluminum-plastic film are broken down through laser to expose the middle aluminum layer, so that the positive electrode tab is in welding contact with the middle aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, dripping conductive silver oil at the welding position of the battery cell, isolating the welding position of the positive electrode lug from air, sealing, and conducting the positive electrode lug and the aluminum layer to play a role in conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through a lead, measuring voltage OCV between the positive electrode and the negative electrode at a direct current voltage gear, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=32h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and if the voltage drop K is less than or equal to 0.05mV/h, indicating that the aluminum-plastic film is complete and the battery cell is well insulated; and if K is more than 0.05mV/h, the inside of the battery cell is corroded, and the aluminum-plastic film is damaged.
Example 10:
as shown in fig. 1 and 2, an identification method for rapidly judging soft package lithium ion battery aluminum plastic film damage includes the following steps:
s1, welding: after the battery cell is packaged, laser welding is carried out on the positive electrode lug and the aluminum plastic film, and the power density of the laser welding is within the range of 6 multiplied by 105W/cm2The outer protective layer and the inner heat-sealing layer of the aluminum-plastic film are broken down through laser to expose the middle aluminum layer, so that the positive electrode tab is in welding contact with the middle aluminum layer of the aluminum-plastic film;
s2, sealing: after welding, dripping conductive silver and copper oil at the welding position of the battery cell to isolate the welding position of the positive electrode lug from air for sealing, and simultaneously conducting the positive electrode lug and the aluminum layer to play a role in conducting electricity;
s3, testing: performing OCV test on the battery cell processed in the step S2, respectively connecting a positive electrode tab and a negative electrode tab of the soft package lithium ion battery with two electrodes of a universal meter through a lead, measuring voltage OCV between the positive electrode and the negative electrode at a direct current voltage gear, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1) Wherein t is2-t1=48h;
S4, judgment: checking whether the voltage drop K of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if K is less than or equal to 0.05mV/h or the appearance of the battery cell is good and has no abnormity, the aluminum-plastic film is complete and the battery cell is good in insulation; if K is more than 0.05mV/h or the phenomena of liquid leakage, breakdown or smoking occur at the edge sealing of the soft package lithium ion battery, the inside of the battery cell is corroded, and the aluminum plastic film is damaged.
The method mainly comprises the steps of breaking down a nylon layer and a PP layer of an aluminum-plastic film through laser to expose a middle aluminum layer, connecting a positive electrode lug with the aluminum layer of the middle layer of the aluminum-plastic film, and causing micro short circuit inside a battery cell if the aluminum-plastic film is damaged, so that current passes through heat-sealing abnormal areas, the internal resistance of the battery is increased, the voltage is reduced to exceed a specified measurement range, and the condition of the yield of the battery cell is rapidly detected.
Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the embodiments or portions thereof without departing from the spirit and scope of the invention.

Claims (10)

1. An identification method for rapidly judging the damage of an aluminum plastic film of a soft package lithium ion battery is characterized by comprising the following steps:
s1, welding: after the battery cell is packaged, welding a positive electrode lug and an aluminum-plastic film to enable the positive electrode lug to be in contact with a middle aluminum layer of the aluminum-plastic film;
s2, sealing: sealing the welding position of the battery cell after welding is finished;
s3, testing: performing a current test or an OCV test on the battery cell processed in step S2;
s4, judgment: checking whether the current or the voltage drop of the battery cell exceeds a normal range, and checking whether the appearance of the battery cell is abnormal; if the current appears, or the voltage drop exceeds the normal range, or the appearance of the battery cell is abnormal, the inside of the battery cell is corroded, and the aluminum-plastic film is damaged.
2. The method for rapidly identifying the soft package lithium ion battery aluminum plastic film damage according to claim 1, wherein in step S1, the outer protection layer and the inner heat seal layer of the aluminum plastic film are broken through welding to expose the middle aluminum layer, and then the positive electrode tab is in welding contact with the middle aluminum layer of the aluminum plastic film.
3. The method for rapidly identifying soft package lithium ion battery aluminum plastic film damage according to claim 1, wherein the welding in step S1 is laser welding.
4. The identification method for rapidly judging the soft package lithium ion battery aluminum plastic film damage according to claim 3, wherein the power density of the laser welding is within the range of 104~106W/cm2
5. The method for rapidly identifying the soft package lithium ion battery aluminum plastic film damage according to claim 1, wherein in step S2, the sealing process is performed by dropping conductive oil onto the cell welding spot.
6. The identification method for rapidly judging the soft package lithium ion battery aluminum plastic film damage according to claim 5, wherein the conductive oil is conductive silver oil, conductive copper oil, conductive nickel oil or conductive silver copper oil.
7. The identification method for rapidly judging the soft package lithium ion battery aluminum plastic film damage according to claim 1, wherein the OCV test in step S3 specifically comprises: respectively connecting the positive electrode tab and the negative electrode tab of the soft package lithium ion battery with two electrodes of a voltage testing device through leads, measuring the voltage OCV between the positive electrode and the negative electrode, and measuring the voltage OCV at time t1OCV measurement1Time t2OCV measurement2Voltage drop K ═ OCV (OCV)1-OCV2)/(t2-t1)。
8. The method for rapidly identifying the soft package lithium ion battery aluminum plastic film damage according to claim 7, wherein the step S4 is specifically performed by the step of determining that the voltage drop of the battery cell exceeds a normal range: the voltage drop K of two voltage tests is more than 0.05 mV/h.
9. The method for rapidly identifying the soft package lithium ion battery aluminum plastic film damage according to claim 1, wherein the current test in step S3 specifically comprises: and respectively connecting the positive electrode lug and the negative electrode lug of the soft package lithium ion battery with two electrodes of a current testing device through leads, and measuring the current between the positive electrode and the negative electrode.
10. The method for rapidly judging the breakage of the aluminum-plastic film of the soft package lithium ion battery according to claim 1, wherein the step S4 of determining the appearance abnormality of the battery cell specifically comprises: the edge sealing of the soft package lithium ion battery has the phenomena of liquid leakage, breakdown or smoking.
CN201910856052.1A 2019-09-11 2019-09-11 Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film Pending CN110672704A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910856052.1A CN110672704A (en) 2019-09-11 2019-09-11 Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910856052.1A CN110672704A (en) 2019-09-11 2019-09-11 Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film

Publications (1)

Publication Number Publication Date
CN110672704A true CN110672704A (en) 2020-01-10

Family

ID=69077836

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910856052.1A Pending CN110672704A (en) 2019-09-11 2019-09-11 Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film

Country Status (1)

Country Link
CN (1) CN110672704A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111403812A (en) * 2020-03-06 2020-07-10 惠州锂威新能源科技有限公司 Edge sealing optimization process
WO2021249341A1 (en) * 2020-06-08 2021-12-16 华为技术有限公司 Lithium ion battery and terminal device comprising lithium ion battery
CN114035112A (en) * 2021-11-09 2022-02-11 新纶新能源材料(常州)有限公司 Soft package lithium ion battery and online detection method for negative short circuit thereof
CN115877210A (en) * 2022-12-08 2023-03-31 青岛艾测科技有限公司 Pressure-maintaining adjustable capacitive load insulation detection method, device and equipment

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101114003A (en) * 2006-07-26 2008-01-30 深圳市邦凯电子有限公司 Shorting or breaking circuit testing method of polyalcohol flexible packing
CN201387476Y (en) * 2009-03-27 2010-01-20 深圳市迪凯特电池科技有限公司 Soft package lithium ion battery leakage detection device
CN103048376A (en) * 2011-10-14 2013-04-17 深圳市海盈科技有限公司 Method for detecting corrosion condition inside lithium ion battery with flexible package
DE102012213110A1 (en) * 2012-07-26 2014-01-30 Leichtbau-Zentrum Sachsen Gmbh Method for manufacturing film battery e.g. lithium ion battery mounted in vehicle, involves forming frame by casting around edge region of film stack, and opening casting tool after removal of a frame which is provided film stack
CN104330710A (en) * 2013-07-22 2015-02-04 浙江万向亿能动力电池有限公司 Method for rapidly judging poor insulation of soft package lithium ion battery aluminium-plastic film
JP2018152260A (en) * 2017-03-14 2018-09-27 日本電気株式会社 Internal short circuit test method and internal short circuit test device of battery
CN208239566U (en) * 2018-06-16 2018-12-14 微宏动力系统(湖州)有限公司 A kind of Insulation Inspection System of battery core shell
CN110137425A (en) * 2019-06-21 2019-08-16 珠海冠宇电池有限公司 A method of improving lithium ion battery electrochemical corrosion

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101114003A (en) * 2006-07-26 2008-01-30 深圳市邦凯电子有限公司 Shorting or breaking circuit testing method of polyalcohol flexible packing
CN201387476Y (en) * 2009-03-27 2010-01-20 深圳市迪凯特电池科技有限公司 Soft package lithium ion battery leakage detection device
CN103048376A (en) * 2011-10-14 2013-04-17 深圳市海盈科技有限公司 Method for detecting corrosion condition inside lithium ion battery with flexible package
DE102012213110A1 (en) * 2012-07-26 2014-01-30 Leichtbau-Zentrum Sachsen Gmbh Method for manufacturing film battery e.g. lithium ion battery mounted in vehicle, involves forming frame by casting around edge region of film stack, and opening casting tool after removal of a frame which is provided film stack
CN104330710A (en) * 2013-07-22 2015-02-04 浙江万向亿能动力电池有限公司 Method for rapidly judging poor insulation of soft package lithium ion battery aluminium-plastic film
JP2018152260A (en) * 2017-03-14 2018-09-27 日本電気株式会社 Internal short circuit test method and internal short circuit test device of battery
CN208239566U (en) * 2018-06-16 2018-12-14 微宏动力系统(湖州)有限公司 A kind of Insulation Inspection System of battery core shell
CN110137425A (en) * 2019-06-21 2019-08-16 珠海冠宇电池有限公司 A method of improving lithium ion battery electrochemical corrosion

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
徐国荣: "《电化学设备与工程设计》", 31 March 2018, 中国矿业大学出版社 *
赵殿礼: "《船舶电气设备与系统》", 30 September 2017, 大连海事大学出版社 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111403812A (en) * 2020-03-06 2020-07-10 惠州锂威新能源科技有限公司 Edge sealing optimization process
CN111403812B (en) * 2020-03-06 2022-08-19 惠州锂威新能源科技有限公司 Edge sealing optimization process
WO2021249341A1 (en) * 2020-06-08 2021-12-16 华为技术有限公司 Lithium ion battery and terminal device comprising lithium ion battery
CN114035112A (en) * 2021-11-09 2022-02-11 新纶新能源材料(常州)有限公司 Soft package lithium ion battery and online detection method for negative short circuit thereof
CN115877210A (en) * 2022-12-08 2023-03-31 青岛艾测科技有限公司 Pressure-maintaining adjustable capacitive load insulation detection method, device and equipment

Similar Documents

Publication Publication Date Title
CN110672704A (en) Identification method for rapidly judging damage of soft package lithium ion battery aluminum plastic film
JP7111235B2 (en) Lithium-ion battery evaluation method, lithium-ion battery manufacturing method, and test system
CN104330710B (en) A kind of method of quick judgement soft bag lithium ionic cell aluminum plastic film defective insulation
CN208239566U (en) A kind of Insulation Inspection System of battery core shell
JP6190783B2 (en) Secondary battery and method for measuring gas generated in secondary battery
US7239147B2 (en) Method and device for inspecting secondary battery precursor and method for manufacturing secondary battery using the inspection method
JP4887581B2 (en) Battery inspection method and inspection apparatus
KR20180046370A (en) A system and a method for testing a battery cell
JP2010212183A (en) Short circuit testing device of battery
KR20130126548A (en) Method and apparatus for checking insulation of pouch type secondary battery
CN111129432A (en) Novel reference electrode and three-electrode system for nondestructive testing of lithium ion battery industry and method
CN105866181B (en) Inspection method and inspection system
CN111766480B (en) Method for detecting poor bottom welding of circular lithium ion battery
JPH11297367A (en) Short-circuit inspecting method and short-circuit inspecting device for electrode group of battery
CN113093056A (en) Method for determining position of short-circuit point in electric core
CN210803936U (en) Electrochromic aluminum-plastic film capable of being used for lithium ion battery
JP2000195565A (en) Inspection method of secondary battery
CN111830324A (en) Aluminum-plastic film insulation test structure and aluminum-plastic film insulation test method
CN111812547A (en) Detection method for power battery module insufficient solder
JP4313625B2 (en) Secondary battery manufacturing method and secondary battery precursor inspection apparatus
CN110957545A (en) Detection method for thermal runaway diffusion in battery
CN112881941B (en) Insulation test method capable of detecting capillary short circuit of battery cell and corresponding battery conduction insulation detector
CN106526497A (en) Device and method for rapidly detecting corrosion danger-hidden points in lithium manganese flexible package battery
KR20180001351A (en) Method of the electrical and physical defect inspection between Lead-acid battery cell
JP4609046B2 (en) Laminated battery inspection 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
RJ01 Rejection of invention patent application after publication

Application publication date: 20200110

RJ01 Rejection of invention patent application after publication