CN101034032A - Accurate detecting method for cavity leakage of lithium-ion battery and device thereof - Google Patents

Accurate detecting method for cavity leakage of lithium-ion battery and device thereof Download PDF

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Publication number
CN101034032A
CN101034032A CN 200710057248 CN200710057248A CN101034032A CN 101034032 A CN101034032 A CN 101034032A CN 200710057248 CN200710057248 CN 200710057248 CN 200710057248 A CN200710057248 A CN 200710057248A CN 101034032 A CN101034032 A CN 101034032A
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CN
China
Prior art keywords
vacuum
battery
cavity
lithium
value
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CN 200710057248
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Chinese (zh)
Inventor
吉跃华
刘志盛
张明昆
赵建
尚利辉
薛龙均
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天津力神电池股份有限公司
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Priority to CN 200710057248 priority Critical patent/CN101034032A/en
Publication of CN101034032A publication Critical patent/CN101034032A/en

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Abstract

This invention relates to a kind of precision test method of lithium ionizaation cell cavity leak and its device. The steps as follows: (1) vacuumize phase, time control at T1:3 to 5 second within, flip the inner vacuum of cell cavity to a certainty value P1;if vacuum degree within T1 can not achieve P1 value, it illustrate battery cavity has obvious leak, judge for badness; (2) keep balance phase: time control at T2:2 to 3 second within, keep cell cavity sealing, keep its vacuum level, stabilize gas path, suppress interference;(3) detection phase: clean display of initiating electron vacuum gauge, time control at T3:1 to 4 second within, detect cell cavity inner vacuum degree's variance delta P, if delta P greater than set value, then cell cavity has micro leak, judge for badness;(4) complete phase, time control at T4:0.2 to 0.5 second, restore cell cavity to normality. This device can proceed automatic discrimination to badness cell, advance detect precision and/or efficiency.

Description

The accurate detecting method of cavity leakage of lithium-ion battery and device thereof

Technical field

The present invention relates to a kind of method and device thereof of lithium ion battery Leak Detection, relate in particular to a kind of accurate detecting method and device thereof of cavity leakage of lithium-ion battery.

Background technology

Sony corporation of Japan and Sanyo were respectively at 1985 and beginning lithium rechargeable battery practical research in 1988, great concern is all revealed to the application table of lithium rechargeable battery at aspects such as communication field, portable type electronic product, electric motor car and Aero-Space in countries in the world, and continuous exploration and improvement have been carried out at the performance of lithium rechargeable battery, particularly manufacturing process.Lithium ion battery is through in recent years high speed development, and it mainly develops and tends towards stability; As the sealing of rectangular cell shell and lid, eliminated early stage Purely mechanical riveted, the sealing of the battery cover of metal shell (mainly being aluminium and alloy, steel etc.) is mainly finalized the design and is being adopted laser bonding; The laser welded seam of uniform and delicate is not only attractive in appearance, and adopts laser bonding to make inside battery space active material be increased, thereby is beneficial to the performance that improves lithium ion battery.But, because laser bonding is subject to the interference of external condition, particularly easily crack during the aluminum-shell battery laser bonding, easily cause the battery sealing-performance after the welding bad, while can't estimate usually, thereby has the major hidden danger of leakage when making the finished product battery.And weld the battery of finishing not fluid injection just, there is slight leakage the semi-manufacture about 80% to be retrieved by welding remedial measures again.Therefore, the method that can accurately detect the sealing of lithium ion battery metal shell and battery cover seems very necessary.

The detection method that adopts during enterprise produces at present is more original, adopts liquid " bubbling " method substantially, the detection that some simple frocks of the employing that also has and ordinarily manometer carry out; But all can not rigorous examination go out battery and whether have leakage, tiny leakage is particularly had no way of detecting at the battery of 100Pa for pressure reduction especially.

Summary of the invention

The objective of the invention is to overcome above-mentioned weak point, provide a kind of structural design simple, detect that step is easy, safe and reliable, the accurate detecting method and the device thereof of obvious results cavity leakage of lithium-ion battery.

The technical solution adopted in the present invention is for achieving the above object: a kind of accurate detecting method of cavity leakage of lithium-ion battery, and it is as follows to it is characterized in that detecting step:

(1) vacuumizing phase, by the method that vacuumizes, the time is controlled in T1:3~5 second, and battery cavity internal vacuum is extracted into certain value P1; If vacuum tightness in the time, do not reach the P1 value at T1, illustrate that then the battery cavity has obvious leak, be judged as badly, wherein P1 is the established standards value;

(2) keep equilibrium stage, the time is controlled in T2:2~3 second, and the sealing that keeps the battery cavity keeps its vacuum tightness, stablize gas circuit, gets rid of interference;

(3) detection-phase, initiating electron vacuum meter show and to make zero, and the time is controlled in T3:1~4 second, detects the variation delta P of battery cavity internal vacuum, if Δ P is greater than setting value, then the battery cavity has tiny leakage, promptly is judged as bad;

(4) finish the stage, the time is controlled at T4:0.2~0.5 second, and recovering the battery inside cavity is normality.

A kind of accurate pick-up unit of cavity leakage of lithium-ion battery, it is characterized in that this device comprises base, support and electric box, described base is provided with two buttons and locking cylinder, corresponding locking cylinder is provided with anchor clamps, locking cylinder is after anchor clamps put in place, promptly lock battery, described base is provided with support, and the support rear side is provided with electric box; At the corresponding respectively pilot lamp that is provided with vacuum valve, vacuum transducer and indicates bad product in the top of electric box; Be fixed with the traction cylinder on the support, connect traction traversing carriage knee-action, be provided with fixedly traversing carriage of line slideway, and correspondence is provided with pressure head and is positioned at by spring and follows operation in the traversing carriage respectively; Described pressure head is a hollow structure, is respectively equipped with O-ring seal in each pressure head end; Gas circuit structure makes pressurized air pick out from source of the gas promptly to connect two actuating cylinders, and the vacuum loop UNICOM identical with each; Vacuum loop comprises joint and the filtrator that is attached thereto, and filtrator connects vacuum transducer; The other end of vacuum transducer is connected to the pressure release solenoid valve that the control vacuum loop opens and closes, and the pressure release solenoid valve is connected vacuum valve respectively with valve.

The invention has the beneficial effects as follows: this device adopts the better suited vacuum transducer of a kind of ratio of precision, in conjunction with special detection architecture, the precision when guaranteeing to detect and the requirement of pressure balance, the accuracy of detection of the pressure leakage amount in the time of can be with battery detecting is controlled at 10Pa, and this device can be differentiated bad battery automatically automatically, improve accuracy of detection, improve detection accuracy, thereby improve detection efficiency.And this apparatus structure need not to be provided with vacuum pump, removes the maintaining work to pump from, and it is simple in structure, and is light and handy flexibly.

Adopt this method and device thereof, be particularly suitable for the detection of the rectangular lithium ion battery welding leakage of aluminum hull or box hat, be provided with a plurality of stations and carry out work, can be according to different parameter settings, efficient generally is controlled at 30ppm, can realize that output was more than 1,200 ten thousand in 1 year; Generally calculate according to present lithium ion battery laser bonding, can detect 24000 welding leakage cell, and retrieve in 1 year and wherein there are 20000 batteries can obtain repairing at the defective products more than 0.2%; Therefore effectively reduce production costs, simultaneously the easily scale of formation industry.

Description of drawings

Fig. 1 is an one-piece construction synoptic diagram of the present invention;

Fig. 2 is an one-piece construction side view of the present invention;

Fig. 3 is apparatus of the present invention gas circuit connection diagram;

Fig. 4 is a vacuum loop J place enlarged diagram among Fig. 3 of the present invention;

Fig. 5 is battery cavity air pressure inside change curve and a non-defective unit distributed areas tracing analysis synoptic diagram in the testing process of the present invention.

Among the figure: 1 vacuum valve bonnet, 2 vacuum transducers, 3 pilot lamp, 4 traction cylinders, 5 pressure heads, 6 O-ring seals, 7 anchor clamps, 8 bases, 9 buttons, 10 electric boxs, 11 supports, 12 traversing carriages, 13 springs, 14 locking batteries, 15 locking cylinders, 16 line slideways, 17 joints, 18 filtrators, 19 valves, 20 vacuum valves, pressure release solenoid valve 21.

Embodiment

Below in conjunction with accompanying drawing and preferred embodiment, details are as follows to embodiment, structure, the feature of the inventive method and device thereof:

A kind of accurate detecting method of cavity leakage of lithium-ion battery is characterized in that implementation step is as follows:

(1) vacuumizing phase, by the method that vacuumizes, the time is controlled in T1:3~5 second, and battery cavity internal vacuum is extracted into certain value P1; If vacuum tightness in the time, does not reach the P1 value at T1, illustrate that then the battery cavity has obvious leak, be judged as bad, wherein P1 be established standards value :-75KPa~-95KPa;

(2) keep equilibrium stage, the time is controlled in T2:2~3 second, and the sealing that keeps the battery cavity keeps its vacuum tightness, stablize gas circuit, gets rid of interference;

(3) detection-phase, initiating electron vacuum meter show and to make zero, and the time is controlled in T3:1~4 second, detects the variation delta P of battery cavity internal vacuum, established standards value: 30Pa~100Pa; If Δ P is greater than setting value, then the battery cavity has tiny leakage, promptly is judged as bad;

(4) finish the stage, the time is controlled at T4:0.2~0.5 second, and this stage mainly is to eliminate vacuum, and recovering the battery inside cavity is normality.

Battery cavity air pressure inside change curve and non-defective unit distributed areas are as shown in Figure 5 in the concrete testing process:

Not reaching P1 in T1 stage vacuum, is that first detected gross leak defective products changes greater than setting value in T2~T3 stage vacuum in the a-quadrant, is the tiny leakage defective products in area B; Change less than setting value in T2~T3 stage vacuum, C is the non-defective unit zone among the figure.

As Fig. 1~shown in Figure 4, a kind of accurate pick-up unit of cavity leakage of lithium-ion battery, it is characterized in that this device is provided with base 8, described base 8 is provided with two buttons 9 and locking cylinder 15, corresponding locking cylinder 15 is provided with anchor clamps 7, locking cylinder 15 is promptly locked battery 14 after anchor clamps 7 put in place, play pinpoint effect; Described base is provided with support 11, and support 11 rear sides are provided with electric box 10; Described support 11 and electric box 10 are set in turn on the base 8; Corresponding respectively 6 vacuum valves 20 and 6 vacuum transducers 2 that are provided with band vacuum valve bonnet 1 on the top of electric box 10, and the corresponding pilot lamp 3 that is provided with 6 bad products of indication; Be fixed with traction cylinder 4 on the support 11, connect traction traversing carriage 12 knee-actions; On support 11, for guaranteeing that running precision adopts fixedly traversing carriage 12 of accurate line slideway 16 up and down, being provided with 6 pressure heads 5 is positioned in the traversing carriage 12 by spring 13 and follows operation, pressure head 5 is a hollow structure, be convenient to vacuumize air current flow, described spring 13 can play the effect of buffering and protection; Be respectively equipped with O-ring seal 6 in each pressure head 5 end, O-ring seal 6 plays sealing function during work between pressure head 5 and battery 14.

Substantially the gas circuit syndeton as shown in Figure 3: pressurized air connects two actuating cylinders respectively after source of the gas picks out, promptly draw cylinder 4 and locking cylinder 15, and identical with 6 again vacuum loop J connects.

The realization of vacuum loop J is as shown in Figure 4: the filtrator 18 that comprises joint 17 and be attached thereto, and filtrator 18 connects vacuum transducers 2; The effect of filtrator 18 is that impurity enters vacuum line damage vacuum transducer 2 when preventing to vacuumize, the other end of vacuum transducer 2 is connected to the pressure release solenoid valve 21 that the control vacuum loop opens and closes, pressure release solenoid valve 21 is connected vacuum valve 20 respectively with valve 19, and valve 19 conductings then external compression air can enter vacuum valve 20 generation negative pressure of vacuum.

During application, opening power rotary switch, energized, eight segment encodes [FF.F] that vacuum transducer 2 is shown in green, when beginning to detect, will install the anchor clamps 7 of battery 14 earlier, be put into the assigned position on the base 8, start button 9 then, and at first positioning cylinder 15 actions clamp battery 14; Draw cylinder 4 then and press down, drive traversing carriage 12 and move downwards, the pressure head 5 in traversing carriage 12 inside descends thereupon, and the straight line precision of decline is guaranteed by line slideway 16.The liquid injection hole of pressure head 5 O-ring seal 6 sealed cells 14 bottom, after putting in place, vacuum valve 20 starts, and begins battery 14 is vacuumized.

After time, vacuum valve 20 cuts out through T1, the pipeline sealing; If inside battery vacuum tightness did not reach setting value and judged that then battery is that big leakage is bad this moment; Enter equilibrium stage, stablize gas circuit, get rid of and disturb, equilibration time is T2; Be detection-phase then, control module can be given vacuum transducer 2 zero branch signals when beginning to detect, and the demonstration of vacuum transducer 2 is made zero, so that show change value of pressure, be T3 detection time.Obtain testing result at last, detect the variation delta P of battery cavity internal vacuum, if Δ P greater than setting value, then the battery cavity has tiny leakage, can be judged as bad.If bad, show that with lighting of red led 3 which battery has problem, pass through the T4 time again, i.e. the deadline, traction cylinder 4 returns, and pressure head 5 breaks away from battery 14, and can pick out bad battery this moment according to the indication of pilot lamp 3.Change the anchor clamps that another installs battery, enter next circulation.T1, T2, T3, T4 are the parameter after testing in the process, and its value can be carried out inside by PLC and be set flexibly; For example: be controlled at T1:3~5 second, T2:2~3 second, T3:1~4 second, T4:0.2~0.5 second.If connect outside timer then can externally directly set and needn't set by PLC.

Be provided with six covers in the detection part present embodiments such as 6 vacuum valves 20 of described vacuum loop J and the corresponding band vacuum valve bonnet 1 that connects, vacuum transducer 2, pilot lamp 3, pressure head 5, O-ring seal 6, also can one cover be set or more than the cover according to actual conditions.

Above-mentioned detailed description of the accurate detecting method and the device thereof of this cavity leakage of lithium-ion battery being carried out with reference to embodiment; be illustrative rather than determinate; therefore in the variation and the modification that do not break away under the general plotting of the present invention, should belong within protection scope of the present invention.

Claims (2)

1, a kind of accurate detecting method of cavity leakage of lithium-ion battery, it is as follows to it is characterized in that detecting step:
(1) vacuumizing phase, by the method that vacuumizes, the time is controlled in T1:3~5 second, and battery cavity internal vacuum is extracted into certain value P1; If vacuum tightness in the time, do not reach the P1 value at T1, illustrate that then the battery cavity has obvious leak, be judged as badly, wherein P1 is the established standards value;
(2) keep equilibrium stage, the time is controlled in T2:2~3 second, and the sealing that keeps the battery cavity keeps its vacuum tightness, stablize gas circuit, gets rid of interference;
(3) detection-phase, initiating electron vacuum meter show and to make zero, and the time is controlled in T3:1~4 second, detects the variation delta P of battery cavity internal vacuum, if Δ P is greater than setting value, then the battery cavity has tiny leakage, promptly is judged as bad;
(4) finish the stage, the time is controlled at T4:0.2~0.5 second, and recovering the battery inside cavity is normality.
2, a kind of accurate pick-up unit of cavity leakage of lithium-ion battery according to claim 1, it is characterized in that this device comprises base, support and electric box, described base is provided with two buttons and locking cylinder, corresponding locking cylinder is provided with anchor clamps, locking cylinder is after anchor clamps put in place, promptly lock battery, described base is provided with support, and the support rear side is provided with electric box; At the corresponding respectively pilot lamp that is provided with vacuum valve, vacuum transducer and indicates bad product in the top of electric box; Be fixed with the traction cylinder on the support, connect traction traversing carriage knee-action, be provided with fixedly traversing carriage of line slideway, and correspondence is provided with pressure head and is positioned at by spring and follows operation in the traversing carriage respectively; Described pressure head is a hollow structure, is respectively equipped with O-ring seal in each pressure head end; Gas circuit structure makes pressurized air pick out from source of the gas promptly to connect two actuating cylinders, and the vacuum loop UNICOM identical with each; Vacuum loop comprises joint and the filtrator that is attached thereto, and filtrator connects vacuum transducer; The other end of vacuum transducer is connected to the pressure release solenoid valve that the control vacuum loop opens and closes, and the pressure release solenoid valve is connected vacuum valve respectively with valve.
CN 200710057248 2007-04-27 2007-04-27 Accurate detecting method for cavity leakage of lithium-ion battery and device thereof CN101034032A (en)

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Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102183345A (en) * 2011-01-31 2011-09-14 中国科学院上海硅酸盐研究所 Sodium sulfur battery pressing and leakage detection device and using method
CN102426082A (en) * 2011-11-14 2012-04-25 中国电子科技集团公司第十八研究所 Method for detecting leak of lithium ion storage battery before liquid injection and sealing
CN102607783A (en) * 2012-04-10 2012-07-25 昆山迈致治具科技有限公司 Pressing jig for detecting air tightness of product
CN102735402A (en) * 2012-07-03 2012-10-17 昆山迈致治具科技有限公司 Semi-automatic vacuum test fixture
CN103076144A (en) * 2012-12-28 2013-05-01 厦门顶科电子有限公司 Method and device for performing seal leakage detection on relay
CN103389194A (en) * 2012-05-11 2013-11-13 万向电动汽车有限公司 Device and method for confirming technological parameters of lithium battery aluminum plastic packaging film heat sealing
CN105319021A (en) * 2015-10-30 2016-02-10 北京新能源汽车股份有限公司 Battery pack seal detection method and system
CN105699026A (en) * 2016-01-22 2016-06-22 上海严复制药系统工程有限公司 Sealing test system and method
CN106092465A (en) * 2016-07-05 2016-11-09 深圳市铂纳特斯自动化科技有限公司 The automatic air leak tester of rectangular cell
CN106153267A (en) * 2016-08-21 2016-11-23 南京国轩电池有限公司 A kind of filling machine fixture air tightness detection apparatus and detection method thereof
CN106441744A (en) * 2016-12-13 2017-02-22 力信(江苏)能源科技有限责任公司 Leakage checking device of lithium ion square power battery and leakage checking process of leakage checking device
CN106556496A (en) * 2016-10-09 2017-04-05 深圳拓邦新能源技术有限公司 Battery negative pressure air-tightness detection method
CN107328534A (en) * 2015-10-13 2017-11-07 吴红平 Welding airtightness test device and its method of testing
CN108258341A (en) * 2018-01-23 2018-07-06 湖南元德科技有限公司 Leak detecting device for battery and battery leak hunting method
CN108692887A (en) * 2018-05-17 2018-10-23 合肥国轩高科动力能源有限公司 A kind of device for detecting lithium ion battery airtightness
CN109186883A (en) * 2018-09-19 2019-01-11 南京国轩电池有限公司 A kind of rectangular lithium ion battery air tightness detecting system and method

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102183345A (en) * 2011-01-31 2011-09-14 中国科学院上海硅酸盐研究所 Sodium sulfur battery pressing and leakage detection device and using method
CN102183345B (en) * 2011-01-31 2014-08-06 上海电气钠硫储能技术有限公司 Sodium sulfur battery pressing and leakage detection device and using method
CN102426082A (en) * 2011-11-14 2012-04-25 中国电子科技集团公司第十八研究所 Method for detecting leak of lithium ion storage battery before liquid injection and sealing
CN102426082B (en) * 2011-11-14 2016-01-20 中国电子科技集团公司第十八研究所 Leak hunting method before a kind of lithium-ions battery fluid injection sealing
CN102607783A (en) * 2012-04-10 2012-07-25 昆山迈致治具科技有限公司 Pressing jig for detecting air tightness of product
CN103389194A (en) * 2012-05-11 2013-11-13 万向电动汽车有限公司 Device and method for confirming technological parameters of lithium battery aluminum plastic packaging film heat sealing
CN102735402B (en) * 2012-07-03 2014-12-24 昆山迈致治具科技有限公司 Semi-automatic vacuum test fixture
CN102735402A (en) * 2012-07-03 2012-10-17 昆山迈致治具科技有限公司 Semi-automatic vacuum test fixture
CN103076144A (en) * 2012-12-28 2013-05-01 厦门顶科电子有限公司 Method and device for performing seal leakage detection on relay
CN103076144B (en) * 2012-12-28 2016-01-20 厦门顶科电子有限公司 A kind of sealing leak hunting method for relay and device thereof
CN107328534A (en) * 2015-10-13 2017-11-07 吴红平 Welding airtightness test device and its method of testing
CN107328534B (en) * 2015-10-13 2019-11-05 吴红平 Welding airtightness test device and its test method
CN105319021A (en) * 2015-10-30 2016-02-10 北京新能源汽车股份有限公司 Battery pack seal detection method and system
CN105699026B (en) * 2016-01-22 2019-07-09 上海严复制药系统工程有限公司 A kind of sealing test system and tightness testing method
CN105699026A (en) * 2016-01-22 2016-06-22 上海严复制药系统工程有限公司 Sealing test system and method
CN106092465A (en) * 2016-07-05 2016-11-09 深圳市铂纳特斯自动化科技有限公司 The automatic air leak tester of rectangular cell
CN106153267A (en) * 2016-08-21 2016-11-23 南京国轩电池有限公司 A kind of filling machine fixture air tightness detection apparatus and detection method thereof
CN106556496A (en) * 2016-10-09 2017-04-05 深圳拓邦新能源技术有限公司 Battery negative pressure air-tightness detection method
CN106441744A (en) * 2016-12-13 2017-02-22 力信(江苏)能源科技有限责任公司 Leakage checking device of lithium ion square power battery and leakage checking process of leakage checking device
CN108258341A (en) * 2018-01-23 2018-07-06 湖南元德科技有限公司 Leak detecting device for battery and battery leak hunting method
CN108692887A (en) * 2018-05-17 2018-10-23 合肥国轩高科动力能源有限公司 A kind of device for detecting lithium ion battery airtightness
CN109186883A (en) * 2018-09-19 2019-01-11 南京国轩电池有限公司 A kind of rectangular lithium ion battery air tightness detecting system and method

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