CN101229607B - Lithium-ion battery laser welding sealing technology - Google Patents
Lithium-ion battery laser welding sealing technology Download PDFInfo
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- CN101229607B CN101229607B CN2007100730184A CN200710073018A CN101229607B CN 101229607 B CN101229607 B CN 101229607B CN 2007100730184 A CN2007100730184 A CN 2007100730184A CN 200710073018 A CN200710073018 A CN 200710073018A CN 101229607 B CN101229607 B CN 101229607B
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- welding
- ion battery
- laser
- battery
- optical
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- 238000003466 welding Methods 0.000 title claims abstract description 103
- 229910001416 lithium ion Inorganic materials 0.000 title claims abstract description 37
- 238000005516 engineering process Methods 0.000 title claims abstract description 25
- 238000007789 sealing Methods 0.000 title claims abstract description 23
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 title claims description 33
- 239000013307 optical fiber Substances 0.000 claims description 37
- 230000000694 effects Effects 0.000 abstract description 9
- 238000001816 cooling Methods 0.000 abstract description 4
- 238000002844 melting Methods 0.000 abstract description 2
- 230000008018 melting Effects 0.000 abstract description 2
- 238000005336 cracking Methods 0.000 abstract 1
- 230000035515 penetration Effects 0.000 description 14
- 230000004927 fusion Effects 0.000 description 13
- 229910000679 solder Inorganic materials 0.000 description 12
- 238000000034 method Methods 0.000 description 9
- 239000007787 solid Substances 0.000 description 9
- 229910052782 aluminium Inorganic materials 0.000 description 6
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 6
- 239000011148 porous material Substances 0.000 description 5
- 239000012535 impurity Substances 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 229910052751 metal Inorganic materials 0.000 description 4
- 239000002184 metal Substances 0.000 description 4
- 208000037656 Respiratory Sounds Diseases 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 238000009864 tensile test Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000002347 injection Methods 0.000 description 2
- 239000007924 injection Substances 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000000048 melt cooling Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000002310 reflectometry Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
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- Y—GENERAL 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
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Laser Beam Processing (AREA)
Abstract
The invention relates to a laser beam welding and sealing technology for Li-ion battery, which realizes consecutive sealing weld to the battery shell and the battery cover of a Li-ion battery using a laser welder with 600 Hz to 20 KHz of output frequency. The laser beam welding and sealing technology for Li-ion battery of the invention carries out a consecutive sealing weld on the Li-ion battery by means of continuous output of laser energy or high frequency of the laser welder. The welding way can maintain the melting state of a welding seem all the time and push forward. The welding has the advantages of good welding effect as well as smooth and beautiful appearance; furthermore, the nugget zone in the welding centre is completely melted during welding; therefore, after cooling, the residual inter-stress of the welding joint is weak and bad phenomena such as cracking is avoided.
Description
[technical field]
The present invention relates to a kind of lithium ion battery sealing process, specifically relate to the continuous laser welding sealing technology of a kind of lithium ion battery.
[background technology]
Traditional lithium-ion battery laser welding sealing adopts the solid laser welding manner, and the solid laser welding manner comes down to means of spot welds, each solder joint have 60%～90% overlapping, the mode that is overlapped by multiple spot so finally realizes the line welding.In traditional welding equipment, maximum pulse rate generally adopts 50 hertz, and speed of welding is 6～8 mm/second.The melting pool shape that said means of spot welds forms is up big and down small parabolic type, under the overlapping situation of multiple spot welding, can cause the fusion penetration of weld seam inhomogeneous.
And the pulse welding belongs to heat conduction weld, and laser radiation heats up the aluminum hull surface to the aluminum hull of battery case, through heat exchange pattern heat is sent to the inner realization welding of material again.Adopt this method welding, the laser energy major part is reflected away by battery aluminum hull surface, and the depth of weld is not dark, at the bottom of the utilization ratio of laser energy.Simultaneously, in the welding of the solid laser of traditional lithium ion battery, weld appearance is the straight line that a series of concentric rings overlap to form, and this weld appearance is not attractive in appearance and the unstable punch-through that forms of pulse energy can occur.
[summary of the invention]
It is good to the objective of the invention is to propose a kind of lithium ion battery welding effect, and weld appearance is smooth, attractive in appearance, and the commissure residualinternal stress is little, and welds continuous laser welding sealing technology.
The technical scheme that realizes above-mentioned purpose is: a kind of lithium-ion battery laser welding sealing technology, using reference frequency output is that the laser-beam welding machine of 600 hertz-20 KHzs seals welding to the battery case and the battery cover board of lithium ion battery.
Said laser-beam welding machine to the battery case of lithium ion battery and battery cover board to seal welding be continuous.
The present invention adopts technique scheme; Its beneficial technical effects is: 1) lithium-ion battery laser welding sealing technology of the present invention adopts the mode that the optical-fiber laser bonding machine laser energy is exported continuously or high-frequency is exported; Lithium ion battery is carried out the continuous welding of sealing, and this welding manner is different from the pulse welding manner of traditional fixed laser bonding machine, and the molten bath of continuous welding mode can keep molten state always and push ahead; Welding effect is good, and weld appearance is smooth, attractive in appearance; 2) the present invention adopts optical-fiber laser welding battery case, and the nugget district of weld seam central area so commissure, cooling back residualinternal stress is little, can not occur bad phenomenon such as crackle owing to be completely melted during welding; 3) optical fiber welding procedure of the present invention can realize the speed of welding of 50 mm/second under 200 watts power, the optical fiber speed of welding is about 6～7 times of conventional laser welding equipment; 4) owing to adopted optical-fiber laser welding procedure of the present invention, the molten bath of battery case keeps molten state before at the uniform velocity, to advance always, so the weld seam that obtains is very even; 5) the present invention is owing to adopted the optical-fiber laser welding procedure; The molten bath of battery case keeps molten state always when making continuous welding; So the aluminum hull of battery case remains on high state to the reflectivity of laser energy always; At this moment the utilization rate of laser energy is the highest, so can under the same laser energy, obtain speed of welding faster; 6) the present invention is owing to adopted the optical-fiber laser welding procedure, and when making continuous laser welding battery case, weld appearance smooth and beautiful appearance, laser energy stability the phenomenon of aluminum hull can not occur puncturing less than 0.5%; 7) among the present invention, optical-fiber laser bonding machine adopts the mode of optical fiber output, when making the anchor clamps of optical fiber laser, greater flexibility can be arranged.
[description of drawings]
Through embodiment and combine accompanying drawing, the present invention is done further detailed description below:
Fig. 1 is the welding pattern of traditional lithium ion battery Solid State Laser solder up technology.
Fig. 2 is the welding pattern of lithium-ion battery laser welding sealing technology of the present invention.
Fig. 3 is the fusion penetration pattern of traditional lithium ion battery Solid State Laser solder up technology.
Fig. 4 is the fusion penetration pattern of lithium-ion battery laser welding sealing technology of the present invention.
[specific embodiment]
The present invention relates to a kind of lithium-ion battery laser welding sealing technology, battery case of lithium ion battery 6 and battery cover board 8 are sealed welding.It is the optical-fiber laser bonding machine of 600 hertz-20 KHzs that said welding procedure is used reference frequency output, to carrying out the continuous welding of sealing between the battery case 6 of lithium ion battery and the battery cover board 8.
In this embodiment, said optical-fiber laser bonding machine adopts the optical-fiber laser bonding machine of 1090 nano wave lengths.Compare the pulse way of output of common laser bonding machine, this kind laser-beam welding machine can be exported laser energy continuously, and its waveform way of output is various simultaneously, can regulate the suitable waveform of material and obtain big fusion penetration ratio.
Please comparison diagram 1 and Fig. 2, Fig. 1 is the welding pattern of traditional lithium ion battery Solid State Laser solder up technology, Fig. 2 is the welding pattern of lithium ion battery optical-fiber laser solder up technology of the present invention.
Please refer to Fig. 1, present existing Solid State Laser welding equipment adopts the pulse mode welding.50 hertz of pulse frequencies, 0.15～0.25 millimeter of some distance, 0.6～0.8 millimeter of spot diameter, speed of welding 7～9 mm/second.Because the influence of pulse welding and laser diffraction, welding effect are the form of annulus stack, sometimes because internal stress influence forms crackle in the commissure.
Please refer to Fig. 2; Lithium-ion battery laser welding sealing technology of the present invention adopts the optical fiber welding manner continuous welding mode that is as the criterion, and the optical-fiber laser bonding machine laser energy is the mode of output or high-frequency output continuously, and lithium ion battery is carried out the continuous welding of sealing; This welding manner is different from the pulse welding manner of traditional fixed laser bonding machine; The molten bath of continuous welding mode can keep molten state always and push ahead, and welding effect is good, and weld appearance is smooth, attractive in appearance.Simultaneously, because the optical-fiber laser bonding machine frequency is very high, the sealing welding and can regard continuous welding as of said battery case.So the molten bath of battery case keeps molten state before at the uniform velocity, to advance under the effect of optical-fiber laser bonding machine always, so the weld seam that obtains is very even.
Among the present invention, the reference frequency output of said optical-fiber laser bonding machine is 600 hertz-20 KHzs.For illustrative purposes, the pulse frequency that adopts in this embodiment is 1000 hertz.0.75 millimeter of laser spot diameter, speed of welding 33～50 mm/second, and can think that optical fiber is welded as continuous welding.Because optical-fiber laser bonding machine has formed the mode of continuous welding, there is obvious metal to melt flow cracks on the weld seam 2, weld seam 2 is smooth, smooth, does not amplify to be difficult to the identification weld mark when observing.Pick out existing orifice region 20 for nugget district 10 and continuous laser welding in the middle of the weld seam 2; These nugget district 10 diameters are 200 microns during speed of welding 33 mm/second; These nugget district 10 diameters were 183 microns when speed of welding was 50 mm/second; Temperature is very high in this nugget district 10, and impurities has been vaporized soon in the metal, so and the good cooling of metal flow property back smooth surface.In the outside in nugget district 10 secondary heat-affected zone is arranged, also be in liquid state during metal solder in this zone, but temperature is lower than nugget district; Flowability is relatively poor relatively; Stayed the pore that impurity vaporization back forms during cooling, 10 microns of pore maximum gauges form orifice region 20.From photo, can find out that weld seam 2 leans on battery case one side pore a lot, and lean on this plate one side almost not have pore, impurity content is higher than battery cover board material in this explanation battery case material.Nugget district 10 bad phenomenon such as crackle can not occur because to melt cooling back residualinternal stress fully during welding little.The pore that stays after the impurity volatilization appears in orifice region 20,5～10 microns of hole diameters, and the degree of depth does not influence sealing and weld strength less than 10 microns.Weldering spot overall width is 700 microns～750 microns.
Among the present invention, the speed of welding of said optical-fiber laser bonding machine is 33 millimeters～50 mm/second.When the welding of the 33 mm/second speed of employing, weld seam 2 width are 750 microns, and fusion penetration is about 0.5 millimeter.When the welding of the 50 mm/second speed of employing, weld seam 2 width are 700 microns, and fusion penetration is about 0.46 millimeter.The optical-fiber laser bonding machine Maximum Power Output is 200 watts; Existing laser welding apparatus power output also can reach 150 watts; But because optical-fiber laser bonding machine has adopted laser energy output waveform and the quasi-continuous welding manner of optimizing, so better welding effect and speed of welding faster under close output energy, have been obtained.
Please comparison diagram 3 and Fig. 4, Fig. 3 is the fusion penetration pattern of traditional lithium ion battery Solid State Laser solder up technology, Fig. 4 is the fusion penetration pattern of lithium ion battery optical-fiber laser solder up technology of the present invention.
Please refer to Fig. 3; From the cutaway view of the welding sample of traditional lithium ion battery Solid State Laser solder up technology, can see the zone, molten bath 30 ' of black; According to measuring fusion penetration is 0.15 millimeter～0.20 millimeter, and weld seam 2 width are 0.6 millimeter～0.8 millimeter, and the fusion penetration ratio is 0.25.
Please refer to Fig. 4, the fusion penetration in the zone, molten bath 30 of the black of the optical fiber welding sample of lithium ion battery optical-fiber laser solder up technology of the present invention is 0.5 millimeter, and weld width is 0.75 millimeter, and the fusion penetration ratio is 0.66.Than seeing, the optical-fiber laser welding effect is fine from fusion penetration, complete penetration the aluminum hull of battery case 6.
The welding sample of lithium ion battery optical-fiber laser solder up technology of the present invention is withstand voltage and tensile test shows, the voltage-withstand test that optical-fiber laser is welded sample shows that the sample withstand voltage surpasses more than 10 kilograms.
Optical-fiber laser welding sample is carried out the tensile test of weld seam 2.The method of tensile test is leaned on one jiao of liquid injection hole for cutting battery open, gets the welding battery case 6 of one section 10 millimeters long.Copper wire is passed liquid injection hole and is fixed on the tensiometer, clamp battery case 6 and tensiometer rightabout pulling simultaneously, read value of thrust from tensiometer with pliers.The optical-fiber laser welding sample of lithium ion battery optical-fiber laser solder up technology of the present invention can bear pulling force and exceed the tensiometer measurement category, the table 1 that specifically attaches as follows.
Table 1
| Withstand voltage | Pulling force | |
| Welding sample of the present invention | ＞10 kilograms | ＞10 kilograms |
| Traditional welding sample | =8 kilograms | =7.5 kilograms |
Optical-fiber laser bonding machine of the present invention adopts the mode of optical fiber output, when making the anchor clamps of optical-fiber laser bonding machine, greater flexibility can be arranged.
Claims (2)
1. lithium-ion battery laser welding sealing technology; It is characterized in that: using reference frequency output is that the optical-fiber laser bonding machine of 600 hertz-20 KHzs seals welding to the battery case and the battery cover board of lithium ion battery, and speed of welding is 33 millimeters～50 mm/second.
2. lithium-ion battery laser welding sealing technology according to claim 1 is characterized in that: said laser-beam welding machine to the battery case of lithium ion battery and battery cover board to seal welding be continuous.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007100730184A CN101229607B (en) | 2007-01-23 | 2007-01-23 | Lithium-ion battery laser welding sealing technology |
| HK09100457.7A HK1121100A1 (en) | 2007-01-23 | 2009-01-16 | Laser seal welding for lithium battery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2007100730184A CN101229607B (en) | 2007-01-23 | 2007-01-23 | Lithium-ion battery laser welding sealing technology |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101229607A CN101229607A (en) | 2008-07-30 |
| CN101229607B true CN101229607B (en) | 2012-07-25 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2007100730184A Expired - Fee Related CN101229607B (en) | 2007-01-23 | 2007-01-23 | Lithium-ion battery laser welding sealing technology |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN101229607B (en) |
| HK (1) | HK1121100A1 (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103545465B (en) * | 2013-10-17 | 2016-05-25 | 杭州山合江新能源技术有限公司 | A kind of energy storage device and assembly method thereof with split type aluminum barrel |
| CN104002046A (en) * | 2014-06-16 | 2014-08-27 | 浙江金开来新能源科技有限公司 | Laser penetration sealing equipment and method of lithium battery |
| CN105870392A (en) * | 2016-05-13 | 2016-08-17 | 深圳市科陆电子科技股份有限公司 | Electrode, battery cell, battery module, as well as preparation method and application of battery module |
| JP6802982B2 (en) * | 2017-03-31 | 2020-12-23 | トヨタ自動車株式会社 | Secondary battery and its manufacturing method |
| CN107175407A (en) * | 2017-06-28 | 2017-09-19 | 大族激光科技产业集团股份有限公司 | Laser welding apparatus and its welding method |
| CN110057995A (en) * | 2019-03-30 | 2019-07-26 | 苏州宇量电池有限公司 | A kind of welding penetration detection method of lithium ion battery aluminum hull |
| CN111451632A (en) * | 2020-04-03 | 2020-07-28 | 恒大新能源汽车(广东)有限公司 | Welding method of battery shell |
| CN114074220A (en) * | 2020-08-20 | 2022-02-22 | 大族激光科技产业集团股份有限公司 | Laser welding method for power battery and sealing nail thereof |
| CN113020829B (en) * | 2021-03-11 | 2023-03-31 | 武汉逸飞激光股份有限公司 | Welding test method for cylindrical capacitor battery current collecting disc shell |
| CN113809444B (en) * | 2021-09-17 | 2024-01-30 | 珠海冠宇电池股份有限公司 | Battery cell |
| CN114012262A (en) * | 2021-11-04 | 2022-02-08 | 深圳市吉祥云科技有限公司 | Metal shell welding method and metal shell |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004327453A (en) * | 2004-07-16 | 2004-11-18 | Hitachi Maxell Ltd | Square sealed storage battery and its manufacturing method |
| JP2006104580A (en) * | 2005-11-09 | 2006-04-20 | Nippon Light Metal Co Ltd | Aluminum alloy sheet having excellent pulse laser weldability |
-
2007
- 2007-01-23 CN CN2007100730184A patent/CN101229607B/en not_active Expired - Fee Related
-
2009
- 2009-01-16 HK HK09100457.7A patent/HK1121100A1/en not_active IP Right Cessation
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004327453A (en) * | 2004-07-16 | 2004-11-18 | Hitachi Maxell Ltd | Square sealed storage battery and its manufacturing method |
| JP2006104580A (en) * | 2005-11-09 | 2006-04-20 | Nippon Light Metal Co Ltd | Aluminum alloy sheet having excellent pulse laser weldability |
Non-Patent Citations (5)
| Title |
|---|
| 刘颂豪.光纤激光器.《光子学技术与应用 上》.广东科技出版社,2006,第320页至第329页. * |
| 张军.Li-ion电池的激光焊接.《中国机械工程》.2001,第12卷213-215. * |
| 朱赫.高功率光纤激光器.《光机电信息》.2005,(第6期),第2页第1栏第18行至20行，第3页第2栏第10行. * |
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| 高兰兰.Nd：YAG激光器在焊接中的应用.《光机电信息》.2004,(第5期),6-7. * |
Also Published As
| Publication number | Publication date |
|---|---|
| HK1121100A1 (en) | 2009-04-17 |
| CN101229607A (en) | 2008-07-30 |
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