CN206293447U - IBC back electrode of solar cell structures - Google Patents
IBC back electrode of solar cell structures Download PDFInfo
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- CN206293447U CN206293447U CN201621386390.1U CN201621386390U CN206293447U CN 206293447 U CN206293447 U CN 206293447U CN 201621386390 U CN201621386390 U CN 201621386390U CN 206293447 U CN206293447 U CN 206293447U
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- main gate
- gate line
- negative pole
- grid line
- line
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- 230000004888 barrier function Effects 0.000 claims abstract description 31
- 238000003466 welding Methods 0.000 claims description 14
- 238000000034 method Methods 0.000 claims description 11
- 238000009413 insulation Methods 0.000 claims description 3
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 238000005245 sintering Methods 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 3
- 239000012634 fragment Substances 0.000 description 3
- 230000005611 electricity Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000002360 preparation method Methods 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- KUNSUQLRTQLHQQ-UHFFFAOYSA-N copper tin Chemical compound [Cu].[Sn] KUNSUQLRTQLHQQ-UHFFFAOYSA-N 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005538 encapsulation Methods 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000010422 painting Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Classifications
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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
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
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- Photovoltaic Devices (AREA)
Abstract
The utility model discloses a kind of IBC back electrode of solar cell structure, including just superfine grid line, the thin grid line of negative pole, positive pole main gate line and negative pole main gate line；Just superfine grid line is parallel to each other and cross arrangement with the thin grid line of negative pole, and just superfine grid line is provided with insulating barrier with the pre-position of the thin grid line of negative pole；Positive pole main gate line is mutually perpendicular to just superfine grid line, and vertical overlapping place is electrically connected with, and positive pole main gate line overlapping place vertical with the thin grid line of negative pole is insulated by insulating barrier；Negative pole main gate line is mutually perpendicular to the thin grid line of negative pole, and vertical overlapping place is electrically connected with, and negative pole main gate line overlapping place vertical with just superfine grid line is insulated by insulating barrier；And positive pole main gate line and negative pole main gate line are respectively positioned on the inside of IBC solar battery sheets.Collected current efficiency is reduced caused by there is breach because of just superfine grid line and the thin grid line of negative pole this configuration avoids traditional IBC solar battery sheets, improves the efficiency of electric current collection.
Description
Technical field
The utility model is related to technical field of solar batteries, more particularly to a kind of IBC back electrode of solar cell structure.
Background technology
Photovoltaic generation is one of major way currently using solar energy, and solar energy power generating is because of its cleaning, safety, just
Sharp, efficient the features such as, it has also become countries in the world common concern and the new industry given priority to.Therefore, further investigate and utilize
Solar energy resources, is of great significance to alleviating crisis of resource, tool of improving the ecological environment.
Wherein, staggeredly back contacts (IBC, Interdigitated back contact) solar cell is photovoltaic cell
One kind, it is designed at the back side of cell piece by by positive and negative electrode, will contact launch site electrode and the electricity for contacting base
Pole is interspersed, and makes cell piece surface without any grid line and conductive welding, completely eliminates the grid line and conduction on cell piece surface
Blocking for welding, so that the full surface of cell piece can receive illumination, can more effectively collect photo-generated carrier, make energy
Conversion efficiency is greatly improved.IBC solar battery sheets have realized that industrialization is up to 24.2% conversion efficiency, at present this
Conversion efficiency is occupied first of the crystal silicon battery of all industrialization productions, is the important directions of following high-efficiency battery development.
The back electrode of IBC solar cells generally includes the thin grid line of some opposed polarities, and those thin grid lines are in interdigital
Shape is arranged, and its quantity is usual between 100-200 roots, meanwhile, cell piece to the encapsulation of component is carried out for convenience, in addition it is also necessary to printed
Main gate line.The structure of existing IBC back electrode of solar cell is as shown in figure 1, wherein, 1 represents positive pole main gate line, and 2 representatives are negative
Pole main gate line, 3 represent just superfine grid lines, and 4 represent the thin grid line of negative pole, traditional IBC solar cells main gate line and thin grid line it
Between insulate implementation method be：Thin grid line is broken and is opened a gap so that the main gate line of opposed polarity passes through, the thin grid of same polarity
Then it is joined directly together with main grid.The way exist defect be：
1) barbed portion of thin grid line cannot collected current, cause battery efficiency to be damaged；
2) because thin grid line has breach, to realize electric current collection, electrode must is located at the both sides of the edge of cell piece.With
As a example by Fig. 1, if the main gate line without left side edge and right side edge, the just superfine grid in left side and the thin grid of negative pole on right side
Electric current cannot be collected.And the design that main gate line whole piece is located at cell piece edge can cause that cell piece both sides are extremely sensitive to stress,
Therefore do not apply to traditional painting tin copper strips mode between the cell piece and cell piece shown in Fig. 1 to be attached, and conducting resinl can only be used
Or the mode of electrocondution slurry, otherwise fragment rate will increase.
Therefore, it is necessary to be improved to the back electrode structure of IBC solar cells.
Utility model content
The purpose of this utility model is to provide a kind of IBC back electrode of solar cell structure, to solve prior art
Above mentioned problem.
To achieve the above object, the technical solution adopted in the utility model is as follows：
A kind of IBC back electrode of solar cell structure, including it is arranged on the just superfine grid in IBC solar cell backs face
The thin grid line of line, negative pole, positive pole main gate line and negative pole main gate line；Wherein, the just superfine grid line and the thin grid line phase of the negative pole
Mutual parallel and cross arrangement, the just superfine grid line is provided with insulating barrier with the pre-position of the thin grid line of the negative pole；It is described
Positive pole main gate line is mutually perpendicular to the just superfine grid line, and vertical overlapping place is electrically connected with, the positive pole main gate line with it is described
Insulated by the insulating barrier at the vertical overlapping place of the thin grid line of negative pole；The negative pole main gate line is mutually hung down with the thin grid line of the negative pole
Directly, and vertically the place of overlapping is electrically connected with, and the negative pole main gate line place of overlapping vertical with the just superfine grid line passes through described exhausted
Edge layer insulate；And positive pole main gate line and negative pole main gate line are respectively positioned on the inside of IBC solar battery sheets, IBC solar cells
The edge of piece is without positive pole main gate line and negative pole main gate line.
In one embodiment of the present utility model, the thickness of the insulating barrier is 5-15 μm.
In one embodiment of the present utility model, the width of the insulating barrier is than corresponding positive pole main gate line or negative pole master
The width 2-4mm wide of grid line.
In one embodiment of the present utility model, in the connection procedure of multiple IBC solar battery sheets, by adjacent electricity
Pond piece rotates 180 ° of placements, and the both positive and negative polarity main gate line of two neighboring cell piece is point-blank.
In one embodiment of the present utility model, in the connection procedure of multiple IBC solar battery sheets, adjacent cell
The both positive and negative polarity main gate line that piece rotates two neighboring cell piece after 180 ° is welded by welding.
In one embodiment of the present utility model, the quantity of the positive pole main gate line and negative pole main gate line for 2 and
More than.
The utility model is allowed to compared with prior art, have the following advantages that and accumulate due to using above technical scheme
Pole effect：
1) the IBC back electrode of solar cell structure that the utility model is provided is by just superfine grid line and the thin grid line of negative pole
Pre-position insulating barrier is set so that between positive pole main gate line and the thin grid line of negative pole and negative pole main gate line and just superfine grid
Insulated by insulating barrier between line, it is to avoid traditional IBC solar battery sheets are because of the thin grid line presence of just superfine grid line and negative pole
The problem of collected current efficiency reduction caused by breach；Improve the efficiency of electric current collection；
2) the IBC back electrode of solar cell structures that the utility model is provided, by just superfine grid line and the thin grid of negative pole
The pre-position of line sets insulating barrier, thus can be not required to set breach on just superfine grid line and the thin grid line of negative pole, from without
Need to set positive pole main gate line and negative pole main gate line in the both sides of the edge of cell piece, it is to avoid traditional IBC batteries are because electrode is two
Lateral edges and the fragment rate that causes problem high, improve the yield rate of cell piece；
3) the IBC back electrode of solar cell structures that the utility model is provided, by just superfine grid line and the thin grid of negative pole
The pre-position of line sets insulating barrier, therefore in the connection procedure of multiple cell pieces, even if welding slightly deflects away from both positive and negative polarity
Main gate line, does not result in cell piece short circuit yet, increased the appearance welded partially to welding and both positive and negative polarity main gate line in welding battery technique
Degree of bearing.
Brief description of the drawings
Fig. 1 is the structural representation of existing IBC back electrode of solar cell；
The structural representation of the IBC back electrode of solar cell that Fig. 2 is provided for the utility model embodiment；
Fig. 3 is the welding schematic diagram of adjacent IBC solar battery sheets；
Fig. 4 A- Fig. 4 C are each for the preparation method of the IBC back electrode of solar cell structures that the utility model embodiment is provided
The corresponding structural representation of step.
Label declaration：
1- positive pole main gate lines, 2- negative pole main gate lines, the just superfine grid lines of 3-, the thin grid line of 4- negative poles, 5- insulating barriers, 6- weldings
Specific embodiment
Below in conjunction with the drawings and specific embodiments to the utility model proposes IBC back electrode of solar cell structures make into
One step is described in detail.According to following explanation and claims, advantages and features of the present utility model will become apparent from.Should be noted
It is that accompanying drawing in the form of simplifying very much and uses non-accurately ratio, is only used for convenience, lucidly aids in illustrating this reality
With the purpose of new embodiment.
Fig. 2 is refer to, as shown in Fig. 2 the IBC back electrode of solar cell structures that the utility model embodiment is provided include
It is arranged on the thin grid line 4 of just superfine grid line 3, negative pole, positive pole main gate line 1 and the negative pole main gate line in IBC solar cell backs face
2；Wherein, just superfine grid line 3 and the thin grid line 4 of negative pole are parallel to each other and cross arrangement, just superfine grid line 3 and the thin grid line 4 of negative pole
Pre-position is provided with insulating barrier 5；Positive pole main gate line 1 is mutually perpendicular to just superfine grid line 3, and vertical overlapping place electrically connects
Connect, the overlapping place vertical with the thin grid line 4 of negative pole of positive pole main gate line 1 is insulated by insulating barrier 5；Negative pole main gate line 2 and the thin grid of negative pole
Line 4 is mutually perpendicular to, and vertical overlapping place is electrically connected with, and the overlapping place vertical with just superfine grid line 3 of negative pole main gate line 2 is by insulation
Layer 5 insulate；And positive pole main gate line 1 and negative pole main gate line 2 are respectively positioned on the inside of IBC solar battery sheets, IBC solar cells
The edge of piece is without positive pole main gate line and negative pole main gate line.
The IBC back electrode of solar cell structure that the utility model embodiment is provided is by thin with negative pole in just superfine grid line
The pre-position of grid line sets insulating barrier so that between positive pole main gate line and the thin grid line of negative pole and negative pole main gate line and positive pole
Insulated by insulating barrier between thin grid line, it is to avoid traditional IBC solar battery sheets are because of just superfine grid line and the thin grid line of negative pole
There is a problem of collected current efficiency reduction caused by breach；Improve the efficiency of electric current collection；
Meanwhile, by the pre-position of just superfine grid line and negative pole thin grid line, insulating barrier is set, thus can be not required to
Breach is set on just superfine grid line and the thin grid line of negative pole, without the both sides of the edge of cell piece set positive pole main gate line with
Negative pole main gate line, it is to avoid traditional IBC batteries improve battery because electrode is in the fragment rate that both sides of the edge cause problem high
The yield rate of piece.
In one embodiment of the present utility model, the thickness of insulating barrier 5 is 5-15 μm.The width of insulating barrier 5 is than correspondence
The width of positive pole main gate line 1 or negative pole main gate line 2 2-4mm wide.Because the presence of insulating barrier 5 and the width of insulating barrier 5 set
Put so that in the connection procedure of multiple cell pieces, even if welding slightly deflects away from both positive and negative polarity main gate line, also do not result in cell piece
Short circuit, increased the tolerance welded partially to welding and both positive and negative polarity main gate line in welding battery technique.As shown in figure 3, multiple batteries
Positive and negative main gate line is welded by welding 6 in piece connection procedure；In the connection procedure of multiple IBC solar battery sheets, will be adjacent
Cell piece rotates 180 ° of placements, and the both positive and negative polarity main gate line of two neighboring cell piece is point-blank.Adjacent cell piece rotates
The both positive and negative polarity main gate line of two neighboring cell piece is welded by welding 6 after 180 °.
In one embodiment of the present utility model, the quantity of positive pole main gate line 1 and negative pole main gate line 2 is 2, when
So, the utility model is not limited thereto, and positive pole main gate line 1 can also be other values, such as 3 with the quantity of negative pole main gate line 2
Root, 4 etc..
Meanwhile, the preparation method of the IBC back electrode of solar cell structures that the utility model embodiment is provided, including it is following
Step：
S1：In the just superfine grid line 3 of the back up of IBC solar battery sheets and the thin grid line 4 of negative pole, wherein just superfine grid line
3 are parallel to each other and cross arrangement with the thin grid line 4 of negative pole, and the structure after printing is as shown in Figure 4 A.
S2:Insulating barrier 5, and the insulating barrier to printing are printed in the pre-position of just superfine grid line 3 and the thin grid line 4 of negative pole
5 are dried；The structure for obtaining is as shown in Figure 4 B；
S3:The vertical friendship of printing positive pole main gate line 1 and negative pole main gate line 2, wherein positive pole main gate line 1 and the thin grid line 4 of negative pole
Folded place is insulated by insulating barrier 5, and the overlapping place vertical with just superfine grid line 3 of negative pole main gate line 2 is insulated by insulating barrier 5.
S4:Sintering, makes to form Ohmic contact, negative pole main gate line 2 and negative pole between positive pole main gate line 1 and just superfine grid line 3
Ohmic contact is formed between thin grid line 4.Wherein, insulating barrier 5 is sold glass paste and is printed using market, and printing width is than master
Grid line width increases 2-4mm, and glass paste requirements of type selecting is：Sintering temperature is less than 800 DEG C, without organic residue after sintering, no
It is SiO containing heavy metal, main component2And Al2O3, insulating barrier penetrates rate between 1.9-2.2 after sintering, and resistivity is not less than 1013
Ω·cm。
Obviously, those skilled in the art can carry out various changes to utility model and modification is new without deviating from this practicality
The spirit and scope of type.So, if it is of the present utility model these modification and modification belong to the utility model claim and its
Within the scope of equivalent technologies, then the utility model is also intended to comprising these changes and modification.
Claims (6)
1. a kind of IBC back electrode of solar cell structure, it is characterised in that including being arranged on IBC solar cell backs face
Just superfine grid line, the thin grid line of negative pole, positive pole main gate line and negative pole main gate line；Wherein, the just superfine grid line and the negative pole
Thin grid line is parallel to each other and cross arrangement, and the just superfine grid line is provided with insulation with the pre-position of the thin grid line of the negative pole
Layer；The positive pole main gate line is mutually perpendicular to the just superfine grid line, and vertical overlapping place is electrically connected with, the positive pole main gate line
Insulated by the insulating barrier at overlapping place vertical with the thin grid line of the negative pole；The negative pole main gate line and the thin grid line of the negative pole
It is mutually perpendicular to, and vertical overlapping place is electrically connected with, the negative pole main gate line overlapping place vertical with the just superfine grid line passes through
The insulating barrier insulation；And positive pole main gate line and negative pole main gate line are respectively positioned on the inside of IBC solar battery sheets, the IBC sun
The edge of energy cell piece is without positive pole main gate line and negative pole main gate line.
2. IBC back electrode of solar cell structure as claimed in claim 1, it is characterised in that the thickness of the insulating barrier is
5-15μm。
3. IBC back electrode of solar cell structure as claimed in claim 1 or 2, it is characterised in that the width of the insulating barrier
Than corresponding positive pole main gate line or the width 2-4mm wide of negative pole main gate line.
4. IBC back electrode of solar cell structure as claimed in claim 1, it is characterised in that in multiple IBC solar cells
In the connection procedure of piece, adjacent cell piece is rotated into 180 ° of placements, the both positive and negative polarity main gate line of two neighboring cell piece is straight at one
On line.
5. IBC back electrode of solar cell structure as claimed in claim 4, it is characterised in that in multiple IBC solar cells
In the connection procedure of piece, the both positive and negative polarity main gate line that adjacent cell piece rotates two neighboring cell piece after 180 ° is welded by welding
Connect.
6. IBC back electrode of solar cell structure as claimed in claim 1, it is characterised in that the positive pole main gate line and
The quantity of negative pole main gate line is each 2-6 roots.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621386390.1U CN206293447U (en) | 2016-12-16 | 2016-12-16 | IBC back electrode of solar cell structures |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201621386390.1U CN206293447U (en) | 2016-12-16 | 2016-12-16 | IBC back electrode of solar cell structures |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN206293447U true CN206293447U (en) | 2017-06-30 |
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ID=59104584
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201621386390.1U Active CN206293447U (en) | 2016-12-16 | 2016-12-16 | IBC back electrode of solar cell structures |
Country Status (1)
| Country | Link |
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| CN (1) | CN206293447U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106653878A (en) * | 2016-12-16 | 2017-05-10 | 国家电投集团西安太阳能电力有限公司 | IBC solar cell back electrode structure and preparation method thereof |
-
2016
- 2016-12-16 CN CN201621386390.1U patent/CN206293447U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106653878A (en) * | 2016-12-16 | 2017-05-10 | 国家电投集团西安太阳能电力有限公司 | IBC solar cell back electrode structure and preparation method thereof |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220317 Address after: 810007 No. 4, Jinsi Road, Dongchuan Industrial Park, Xining City, Qinghai Province Patentee after: Xining solar power branch of Qinghai upper Yellow River Hydropower Development Co.,Ltd. Patentee after: Xi'an solar power branch of Qinghai upper Yellow River Hydropower Development Co.,Ltd. Patentee after: HUANGHE HYDROPOWER DEVELOPMENT Co.,Ltd. Patentee after: QINGHAI HUANGHE HYDROPOWER DEVELOPMENT Co.,Ltd. Address before: 710100 Shaanxi Xi'an space base east Chang'an Avenue 589 Patentee before: STATE POWER INVESTMENT CORPORATION XI'AN SOLAR POWER Co.,Ltd. |
|
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20240112 Address after: 810008 No. 43, Wusi West Road, Chengxi District, Xining City, Qinghai Province Patentee after: QINGHAI HUANGHE HYDROPOWER DEVELOPMENT Co.,Ltd. Address before: 810007 No. 4, Jinsi Road, Dongchuan Industrial Park, Xining City, Qinghai Province Patentee before: Xining solar power branch of Qinghai upper Yellow River Hydropower Development Co.,Ltd. Patentee before: Xi'an solar power branch of Qinghai upper Yellow River Hydropower Development Co.,Ltd. Patentee before: HUANGHE HYDROPOWER DEVELOPMENT Co.,Ltd. Patentee before: QINGHAI HUANGHE HYDROPOWER DEVELOPMENT Co.,Ltd. |