CN113731865A - Solar cell sorting method - Google Patents
Solar cell sorting method Download PDFInfo
- Publication number
- CN113731865A CN113731865A CN202111034362.9A CN202111034362A CN113731865A CN 113731865 A CN113731865 A CN 113731865A CN 202111034362 A CN202111034362 A CN 202111034362A CN 113731865 A CN113731865 A CN 113731865A
- Authority
- CN
- China
- Prior art keywords
- solar cell
- temperature
- solar
- sorting method
- reverse
- 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
Links
- 238000000034 method Methods 0.000 title claims abstract description 35
- 230000005684 electric field Effects 0.000 claims abstract description 48
- 238000001514 detection method Methods 0.000 claims abstract description 45
- 230000009471 action Effects 0.000 claims abstract description 16
- 238000002073 fluorescence micrograph Methods 0.000 claims description 14
- 238000001931 thermography Methods 0.000 claims description 10
- 230000008859 change Effects 0.000 claims description 6
- 230000003287 optical effect Effects 0.000 claims description 5
- 230000015556 catabolic process Effects 0.000 description 32
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 20
- 229910052710 silicon Inorganic materials 0.000 description 20
- 239000010703 silicon Substances 0.000 description 20
- 235000012431 wafers Nutrition 0.000 description 15
- 238000012360 testing method Methods 0.000 description 10
- 238000010586 diagram Methods 0.000 description 4
- 238000000799 fluorescence microscopy Methods 0.000 description 4
- 238000004020 luminiscence type Methods 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 230000017525 heat dissipation Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000011160 research Methods 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 238000012216 screening Methods 0.000 description 3
- 239000004065 semiconductor Substances 0.000 description 3
- 238000009825 accumulation Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 230000020169 heat generation Effects 0.000 description 2
- 238000003331 infrared imaging Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000010801 machine learning Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07C—POSTAL SORTING; SORTING INDIVIDUAL ARTICLES, OR BULK MATERIAL FIT TO BE SORTED PIECE-MEAL, e.g. BY PICKING
- B07C5/00—Sorting according to a characteristic or feature of the articles or material being sorted, e.g. by control effected by devices which detect or measure such characteristic or feature; Sorting by manually actuated devices, e.g. switches
- B07C5/34—Sorting according to other particular properties
- B07C5/344—Sorting according to other particular properties according to electric or electromagnetic properties
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B07—SEPARATING SOLIDS FROM SOLIDS; SORTING
- B07C—POSTAL SORTING; SORTING INDIVIDUAL ARTICLES, OR BULK MATERIAL FIT TO BE SORTED PIECE-MEAL, e.g. BY PICKING
- B07C5/00—Sorting according to a characteristic or feature of the articles or material being sorted, e.g. by control effected by devices which detect or measure such characteristic or feature; Sorting by manually actuated devices, e.g. switches
- B07C5/34—Sorting according to other particular properties
- B07C5/342—Sorting according to other particular properties according to optical properties, e.g. colour
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02S—GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES
- H02S50/00—Monitoring or testing of PV systems, e.g. load balancing or fault identification
- H02S50/10—Testing of PV devices, e.g. of PV modules or single PV cells
-
- 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
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Landscapes
- Photovoltaic Devices (AREA)
Abstract
The invention discloses a solar cell sorting method. The solar cell sorting method comprises the following steps: introducing reverse voltage for the solar cell to be sorted through a reverse external electric field, and controlling the action duration of the reverse voltage to be greater than or equal to a duration threshold, wherein the duration threshold is not less than the duration required by the solar cell to reach dynamic balance; collecting detection parameters of the solar cell; and grading the solar cell by using the target detection parameters generated after the detection parameters belong to the time length threshold. The solar cell sorting method can effectively sort out qualified solar cells, so that the hot spot temperature and the hot spot risk of a solar module prepared by the solar cells are reduced.
Description
Technical Field
The invention relates to a solar cell sorting method.
Background
With the adoption of large-size silicon wafers for manufacturing solar cells, the hot spot problem of the solar cells becomes more and more worried risk. In order to reduce the probability of hot spots, solar cells are generally sorted to obtain acceptable solar cells.
Currently, the sorting of solar cells is mainly performed by reverse leakage current in an IV test. The reverse leakage current in the IV test is that reverse voltage which is gradually increased from 0V to about 17 volts (V) is applied to the battery within 10 ms-30 ms, and the current value loaded on the solar battery is collected at the same time; and grading the solar cell by using the current value.
The existing solar cell sorting mode is not consistent with the working state of the solar module when hot spots are formed in the actual use, so that the hot spot temperature of the solar module cannot be obviously reduced through the existing solar cell sorting mode, and the hot spot risk cannot be obviously reduced.
Disclosure of Invention
In view of the above, the present invention provides a method for sorting solar cells, which can effectively sort out qualified solar cells, thereby reducing the hot spot temperature and the hot spot risk of a solar module manufactured by the solar cells.
In order to solve the technical problems, the invention provides the following technical scheme:
in a first aspect, the present invention provides a method for sorting solar cells, comprising:
introducing reverse voltage for the solar cell to be sorted through a reverse external electric field, and controlling the action duration of the reverse voltage to be greater than or equal to a duration threshold;
collecting detection parameters of the solar cell;
and (c) grading the solar cell by using the target detection parameters generated after the detection parameters belong to the duration threshold.
In a second aspect, the present invention provides a solar cell sorting system, which is applied to the system of the solar cell sorting method provided in the first aspect.
The technical scheme of the first aspect of the invention has the following advantages or beneficial effects: when the solar cell is in use, if reverse voltage is applied, avalanche breakdown can be generated after the reverse voltage is applied for a period of time, and the solar cell can reach a dynamic balance state after heating and heat dissipation after a period of time. In addition, because the hot spot effect generated by the solar cell is related to avalanche breakdown, and the solar cell is always in a temperature accumulation stage from the avalanche breakdown to a dynamic equilibrium state, the difference between solar cells of different grades or grades is not obvious in the temperature accumulation stage, and the dynamic equilibrium state of the solar cells of different grades or grades is different. Based on this, the embodiment of the invention introduces reverse voltage into the solar cell to be sorted, and controls the action duration of the reverse voltage to be greater than or equal to the duration threshold, wherein the duration threshold is not less than the duration required by the solar cell to reach dynamic balance, so that the detection parameters generated after the collected duration threshold can reflect the situation of the solar cell more truly, and then the solar cell is graded by using the detection parameters generated after the detection parameters belong to the duration threshold, so as to effectively improve the grading accuracy of the solar cell, and further reduce the hot spot risk of the solar module where the solar cell is located.
Drawings
FIG. 1 is a schematic diagram of the relationship between the breakdown voltage and the doping concentration required for avalanche breakdown of a semiconductor material provided in accordance with the present invention;
FIG. 2 is a graph illustrating the relationship between doping concentration and bulk resistivity of a solar silicon wafer according to the present invention;
fig. 3 is a schematic diagram of a main flow of a solar cell sorting method according to an embodiment of the present invention;
FIG. 4 is a fluorescence plot of a solar cell provided in accordance with the present invention without avalanche breakdown;
FIG. 5 is a fluorescence plot of a solar cell provided in accordance with the present invention in which avalanche breakdown occurs;
fig. 6 is a schematic diagram of the variation of instantaneous reverse leakage data of the a-class battery and the B-class battery in the conventional IV test according to the present invention.
Detailed Description
Generally, under the action of a fixed reverse applied electric field, the reverse current of the solar cell is not a constant value, but varies depending on the temperature of the solar cell and the application time of the applied electric field. As a semiconductor material, a solar cell is known, which has a phenomenon of sudden increase of reverse current under the action of a reverse applied electric field, i.e., so-called avalanche breakdown. The voltage of the reverse applied electric field when avalanche breakdown occurs is the breakdown voltage. After the avalanche breakdown occurs, electrons and holes generated by the solar cell may collide with electrons in other atoms, and then an avalanche effect occurs, thereby causing a further increase in reverse current. The increase of the reverse current can obviously improve the heat generation of the solar cell, and more electrons and holes can be generated along with the increase of the temperature of the solar cell, so that the reverse current is further improved. Meanwhile, as the temperature of the solar cell rises, the heat dissipation of the solar cell to the environment also begins to increase, and finally the heat generation and the heat dissipation of the solar cell reach balance, namely the solar cell reaches a dynamic balance state. Due to the cumulative effect of temperature, the solar cell must reach the dynamic equilibrium state after avalanche breakdown.
In addition, it has been found through research that the breakdown voltage required for the semiconductor material to undergo avalanche breakdown is related to its doping concentration, as shown in fig. 1. For silicon, when the doping concentration exceeds 1017cm-3When the voltage is high, the breakdown voltage is only about 15V. In recent years, the bulk resistivity of solar silicon wafers used in solar cells has been decreasing, and the doping concentration thereof has been increasing. As shown in fig. 2, which is a relation curve between the doping concentration and the bulk resistivity of the solar silicon wafer, it can be seen from fig. 2 that the bulk resistivity is continuously decreased as the doping concentration of the solar silicon wafer is increased. Particularly, after gallium-doped silicon wafers with bulk resistivity less than 1 Ω · cm are gradually used in the industry, although the lowest average resistivity of the current silicon wafers is still controlled to be more than 0.3 Ω · cm, the local resistivity in the impurity-enriched region may be less than 0.3 Ω · cm due to non-uniformity of silicon crystal growth, i.e., the doping concentration is more than 1017cm-3If, ifWhen a reverse voltage exceeding 10-20V is applied, avalanche breakdown occurs in the region. In addition, when solar cell hot spot occurs, the reverse voltage applied to the hot spot cell is about 15V, so that avalanche breakdown easily occurs, and the hot spot temperature rapidly rises.
In conclusion, as the resistivity of a silicon wafer is reduced, avalanche breakdown becomes a completely new dominant factor influencing the hot spot risk of a solar cell module. However, in the process of grading or rejecting solar cells which are easy to have avalanche breakdown by the existing screening means, detection parameters are generally collected immediately after an external electric field is applied or reaches a specific value, and at the moment, the solar cells still do not reach a dynamic balance state, so that the solar cells which are easy to have avalanche breakdown cannot be effectively identified.
In order to solve the problem of low screening accuracy at present, the scheme provided by the embodiment of the invention selects the acquired detection parameters after the dynamic balance of the solar cell is achieved, because the detection parameters after the dynamic balance of the solar cell is achieved can reflect the actual situation of the solar cell more truly.
Fig. 3 is a schematic diagram illustrating a main flow of a solar cell sorting method according to an embodiment of the present invention.
As shown in fig. 3, a method for sorting solar cells according to an embodiment of the present invention may include the following steps:
step S301: introducing reverse voltage for the solar cell to be sorted through a reverse external electric field, and controlling the action duration of the reverse voltage to be greater than or equal to a duration threshold, wherein the duration threshold is not less than the duration required by the solar cell to reach dynamic balance;
the reverse external electric field can be realized by connecting a power supply to the solar cells to be sorted, wherein the electric field direction of the reverse external electric field is from the N-type region of the solar cells to the P-type region.
In this step, the duration threshold is greater than or equal to 0.1 seconds(s). Research shows that the duration threshold is greater than or equal to 0.1s, so that most of solar cells can reach a dynamic balance state, the detection requirements of most of solar cells can be met by setting the duration threshold to be greater than or equal to 0.1s, and most of solar cells can be graded accurately.
In addition, the reverse voltage acting time can be controlled to be less than or equal to 10s in the step. For example, the reverse voltage may be applied for 0.1s, 0.2s, 0.5s, 1s, 1.5s, 2s, 4s, 5s, 7s, 7.5s, 8s, 9s, 10s, or the like. By controlling the reverse voltage action time to be less than or equal to 10s, the requirement of accurate grading of the solar cell is met, and meanwhile, resources consumed in the sorting process of the solar cell are not excessively consumed, so that the utilization rate of the resources is ensured.
In the step, the value of the reverse voltage is within 5-30V. For example, the reverse voltage may be 5V, 6V, 8V, 10V, 13V, 15V, 17V, 19V, 20V, 22V, 25V, 28V, 30V, etc. The solar cell can reach a dynamic balance state through the reverse voltage so as to further improve the accuracy of grading.
Step S302: collecting detection parameters of the solar cell;
the detection parameters may include: a fluorescence image, a thermographic image, a temperature, and a current loaded on the battery.
The fluorescence luminescent image can be obtained by integrating the existing fluorescence imaging system and a power supply source of a reverse external electric field into the same system and performing fluorescence imaging on the solar cell applied with the reverse external electric field through the existing fluorescence imaging system. The solar cell having the avalanche breakdown forms a bright spot of fluorescence in the area where the avalanche breakdown occurs, as shown in fig. 5. However, the area of the solar cell where avalanche breakdown does not occur, even the solar cell where avalanche breakdown does not occur, will not form a bright fluorescent spot, as shown in fig. 4.
The thermal imaging image can be obtained by a thermal imaging device integrated in the solar cell sorting system. If the solar cell has a region where avalanche breakdown occurs, the temperature of the region where avalanche breakdown occurs is significantly higher than that of other regions where avalanche breakdown does not occur, and therefore, the image pixel value or the image gray scale of the region where avalanche breakdown occurs is significantly different from the image pixel value or the image gray scale of the region where avalanche breakdown does not occur.
The temperature of different positions of the solar cell can be detected by the temperature detection device of the solar cell aiming at the temperature. Due to the quality difference of the solar cells, under the action of a reverse external electric field, the temperature rise conditions of the solar cells are obviously different. Therefore, the embodiment of the invention also uses the temperature as a grading index of the solar cell.
The current applied to the battery can be detected by integrating an existing current detecting device, which detects the current applied to the battery, into the solar cell sorting system, so that differentiated currents are generated when the same voltage is applied to solar cells of different grades or grades. Therefore, the embodiment of the invention also takes the current loaded on the battery as a grading index of the solar battery.
It should be noted that, in the step, the detection parameters are collected generally along with the extension of the action duration of the external directional electric field, and the detection parameters corresponding to a plurality of time points are collected. The plurality of time points may be all time points after the duration threshold, or may be a combination of time points before the duration threshold and time points after the duration threshold.
Step S303: and grading the solar cell by using the target detection parameters generated after the detection parameters belong to the time length threshold.
Generally, the step of grading the solar cell includes comparing a target detection parameter generated after the detection parameter belongs to a duration threshold value with parameter ranges of different grades, and determining that the solar cell belongs to a grade if the target detection parameter generated after the detection parameter belongs to the duration threshold value is within the parameter range of the grade. The parameter ranges of different grades, such as the gray scale range of the fluorescent image of the A-grade battery and the gray scale range of the fluorescent image of the B-grade battery, can be determined by each solar cell manufacturer or user according to the requirements of the manufacturer or the user, a large number of solar cells can be tested under the same detection environment, and the parameter ranges can be determined by a manual mode or a machine learning mode according to the test results.
Wherein, for the case that the detection parameter includes a fluorescence emission image, the first specific implementation of step S303 may include: calculating any one or more of the area of the image lightening area in the fluorescence image, the average gray value of the fluorescence image and the gray value of the designated area in the fluorescence image; and grading the solar cells by using the calculated results. The area of the image lightening area in the fluorescence image, the average gray value of the fluorescence image and the gray value of the designated area in the fluorescence image can be calculated by adopting the existing calculation mode.
For the case where the detection parameter includes a fluorescence emission image and/or a thermal imaging image, the second specific embodiment of step S303 may include: and grading the solar cells by using an automatic optical detection algorithm. The automatic optical detection algorithm is trained by the detected parameters of the solar cell, such as the gray value of the fluorescence image, the area of the luminous region, the gray value of the luminous region and the like.
For the case where the detection parameter comprises a thermographic image, a third specific implementation of this step S303 may comprise: calculating any one or more of an average temperature of the entirety of the solar cell, a maximum temperature of the entirety of the solar cell, an average temperature of a specified region in the solar cell, and a maximum temperature of a specified region in the solar cell, from the thermal imaging image; and grading the solar cells by using the calculated results. In addition, the step S303 may also estimate the area of the region where the avalanche breakdown occurs, the temperature rise of the region where the avalanche breakdown occurs, and the like based on the image pixel value or the image gradation with respect to the thermal imaging image, so that the solar cell may be classified based on the result of the estimation.
For the case where the detected parameter includes temperature and/or current applied to the battery, a fourth specific implementation of step S303 includes: and grading the solar cell by using the change of the collected temperature values and/or current values along with time. The collected temperature values may include temperature values before the duration threshold and temperature values after the duration threshold, or may only include temperature values after the duration threshold. The collected plurality of current values may include current values before the duration threshold value and current values after the duration threshold value, or may include only current values after the duration threshold value.
In addition, the specific embodiment of step S303 may be: and selecting the current or the temperature of two fixed points after the time length threshold, calculating the current ratio or the temperature ratio of the two fixed points, and grading the solar cell according to the calculated current ratio or the calculated temperature ratio. The fixed point generally refers to a collection point of a target detection parameter, where the reverse applied electric field application time is fixed and the voltage of the reverse applied electric field is also fixed (for example, the reverse applied electric field time is 0.3s, the reverse applied electric field voltage is 5V; for example, the reverse applied electric field time is 0.6s, and the reverse applied electric field voltage is 10V) for different solar cells. It is worth to be noted that the voltage of the reverse applied electric field can be applied by a program boosting method, and the program boosting process is consistent in the process of sorting different solar cells. The current ratio of the two fixed points may be a ratio of the current of the previous fixed point to the current of the next fixed point in the currents collected by the two fixed points, or a ratio of the current of the next fixed point to the current of the previous fixed point. The temperature ratio of the two fixed points can be the temperature of the former fixed point to the temperature of the latter fixed point in the temperatures collected by the two fixed points, or the temperature of the latter fixed point to the temperature of the former fixed point.
The basis for grading the solar cells according to the calculated current ratio or temperature ratio is mainly that after the reverse external electric field is applied to the solar cells of different grades, the current and the temperature generated by the solar cells of different grades have obvious difference along with the extension of the application time of the reverse external electric field. Particularly, after the application time of the reverse external electric field exceeds a time threshold, the current change or the temperature change of the solar cells of different grades can generate difference along with the time extension, and the current ratio or the temperature ratio of the two fixed points calculated in the prior art can obviously reflect the difference of the current change or the difference of the temperature change of the solar cells of different grades through research.
In addition, an embodiment of the present invention further provides a solar cell sorting system, which is applied to the system of the solar cell sorting method provided in the first aspect. The solar cell sorting system can comprise a power supply for applying a reverse electric field to the solar cell, and detection equipment for collecting detection parameters, such as fluorescence imaging equipment, thermal imaging equipment, current detection equipment, temperature detection equipment and the like. For example, a silicon camera with a filter mounted in front of a probe row or a contact table, a lens or other cameras with good response to 1000-1500 nm near infrared light, a control computer with an image acquisition card, control and sorting software loaded on the computer, and the like.
The solar cell sorting method is described in detail below with several specific examples.
The first embodiment is as follows: solar cells made from 210mm by 210mm silicon wafers were sorted.
Applying a 15V reverse external electric field to the solar cell, controlling the action time of the reverse external electric field to be 1 second(s), while applying a reverse external electric field, collecting a fluorescence image (namely EL image) of the solar cell by using a silicon camera with a light filter arranged in front of a lens or other cameras with better response to 1000-1500 nm near infrared light, sending the collected fluorescence image to control and sorting software loaded on a control computer (the control is provided with an image collecting card), the control and sorting software applied an automated optical detection algorithm based on the image luminescence area and the fluorescence luminescence image acquired after 0.1s, sorted the cells, wherein, a typical graph of the a-class battery is shown in fig. 4, and a typical graph of the B-class battery is shown in fig. 5, wherein the luminous region of fig. 5 is the region where avalanche breakdown occurs.
The screened A-grade cell, the screened B-grade cell and the unsorted cell are respectively manufactured into solar modules and subjected to hot spot test, and experimental results show that the hot spot temperature of the solar modules manufactured by the A-grade solar cells sorted by the solar cell sorting method provided by the embodiment is 90-110 ℃, the hot spot temperature of the solar modules manufactured by the B-grade cell is 150-180 ℃, and the hot spot temperature of the solar modules manufactured by the unsorted solar cells is as high as 130-180 ℃.
Fig. 6 shows the reverse leakage data detected for a class a battery pack class B battery sorted according to the method when a 15V reverse plus battery was applied during a conventional IV test. As can be seen from fig. 6, although the average value of the leakage of the a-class battery is slightly smaller than that of the B-class battery, under the condition that the action time of the reverse externally-applied battery is short, the data may be seriously crossed, and often the data cannot be effectively distinguished, that is, the prior art cannot achieve the sorting effect of the embodiment. The battery sorted by adopting the reverse leakage current of the traditional IV test is characterized in that a reverse voltage continuously changing from 0 to 17V is applied to the battery within 30ms, and a current value loaded on the battery when 12V is collected, wherein the current value is less than 0.2A, and the battery is a sorted qualified battery. As can be seen from the experimental results shown in fig. 6, the conventional reverse leakage current sorting method cannot effectively reduce the hot spot temperature of the solar module. The method provided by the embodiment can obviously reduce the hot spot temperature of the assembly and avoid the hot spot risk of the assembly.
Example two: solar cells made from 210mm by 210mm silicon wafers were sorted.
Firstly, applying a 15V reverse external electric field to the solar cell, controlling the action time of the reverse external electric field to be 1s, detecting the temperature of a designated area of the cell by using a temperature probe after applying the external electric field for 0.5s, wherein the cell below 80 ℃ is classified into an A-grade cell, the cell below 80-110 ℃ is classified into a B-grade cell, and the cell above 110 ℃ is classified into a C-grade cell.
The screened A-grade cell, B-grade cell, C-grade cell and unsorted cell in the first embodiment are respectively manufactured into solar modules and subjected to hot spot test, and experimental results show that the hot spot temperature of the solar module manufactured by the A-grade cell is 90-110 ℃, the hot spot temperature of the solar module manufactured by the B-grade cell is 100-120 ℃, the hot spot temperature of the solar module manufactured by the C-grade cell is 110-180 ℃, and the hot spot temperature of the solar module manufactured by the unsorted cell is 130-180 ℃.
Example three: solar cells made from 182mm by 182mm silicon wafers were sorted.
The specific implementation manner is similar to the second embodiment, except that after 0.2s from the application of the reverse applied electric field, the thermal imaging graph of the electric field surface is shot by using infrared imaging, and the average temperature of the designated area is used as the grading basis, so that the results similar to the second embodiment can be realized.
Example four: solar cells made from 210mm by 210mm silicon wafers were sorted.
Firstly, applying a 15V reverse external electric field to the solar cell, controlling the action time of the reverse external electric field to be 1s, collecting the current value loaded on the cell at the moment when the reverse external electric field is applied for 0.5s, classifying the cell with the current value less than 0.5A into an A-grade cell, classifying the cell with the current value less than 0.5-1.0A into a B-grade cell, and classifying the cell with the current value more than 1.0A into a C-grade cell.
The fourth embodiment is used for screening the A-grade battery, the B-grade battery and the C-grade battery and the battery which is sorted by adopting the reverse leakage current of the traditional IV test to respectively manufacture solar components and carry out hot spot test, and the experimental result shows that the hot spot temperature of the solar component manufactured by applying the A-grade battery is 90-110 ℃, the hot spot temperature of the solar component manufactured by applying the B-grade battery is 100-120 ℃, the hot spot temperature of the solar component manufactured by applying the C-grade battery is 110-180 ℃, and the hot spot temperature of the solar component manufactured by the unsorted solar battery is 130-180 ℃.
Example five: solar cells made from 210mm by 210mm silicon wafers were sorted.
The specific implementation manner is similar to that of the fourth embodiment, except that the voltage applied with the reverse applied electric field is 20V, and after 0.1s from the beginning, the thermal imaging graph of the electric field surface is shot by using infrared imaging, and the average temperature of the designated area is used as the grading basis, so that the similar result to that of the fourth embodiment can be achieved.
Example six: solar cells made from 182mm by 282mm silicon wafers were sorted.
And applying a reverse external electric field which is increased from 0V to 12V at a constant speed to the solar cell, and controlling the action time of the reverse external electric field to be 1 s. Then, current values I1 and I2 loaded on the battery when the voltage is 5 volts (the acting time of the reverse applied electric field reaches about 0.42 s) and 10 volts (the acting time of the reverse applied electric field reaches about 0.84 s) are collected (the time required by the reverse applied electric field to rise to the voltage of 5 volts and the time required by the 10 volts are both behind a time threshold (such as 0.1)), and the battery with the I2/I1 of less than 2 is classified into A-grade batteries. Solar modules made from A-grade cells obtained by the method also have low hot spot temperature.
Example seven: solar cells made from 182mm by 282mm silicon wafers were sorted.
The specific implementation manner is similar to that of the embodiment, except that the voltage applied with the reverse applied electric field is 30V, and after 0.5s, a silicon camera with a light filter arranged in front of a lens or other cameras with better response to near infrared light of 1000-1500 nm are adopted to collect the fluorescence luminescence image of the solar cell, and an automatic optical detection algorithm is applied according to the luminescence area of the image, so that the result similar to that of the embodiment can be realized.
The above steps are provided only for helping to understand the method, structure and core idea of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the principles of the invention, and these changes and modifications also fall within the scope of the appended claims.
Claims (10)
1. A method of sorting solar cells, comprising:
introducing a reverse voltage to the solar cell to be sorted through a reverse external electric field, and controlling the action duration of the reverse voltage to be greater than or equal to a duration threshold, wherein the duration threshold is not less than the duration required by the solar cell to reach dynamic balance;
collecting detection parameters of the solar cell;
and (c) grading the solar cell by using the target detection parameters generated after the detection parameters belong to the duration threshold.
2. The solar cell sorting method according to claim 1,
the duration threshold is greater than or equal to 0.1 seconds.
3. The solar cell sorting method of claim 2, wherein step (a) further comprises:
and controlling the action time of the reverse voltage to be less than or equal to 10 seconds.
4. The solar cell sorting method according to claim 1, wherein the detecting the parameter comprises:
a fluorescence image, a thermographic image, a temperature, and a current loaded on the battery.
5. The solar cell sorting method according to claim 1,
the reverse voltage is within 5-30V.
6. The solar cell sorting method according to claim 4,
for the case where the detection parameter comprises a fluorescence emission image,
the step (c) includes: calculating any one or more of the area of an image lightening region in the fluorescence image, the average gray value of the fluorescence image and the gray value of a specified region in the fluorescence image; and grading the solar cells by using the calculated results.
7. The solar cell sorting method according to claim 4,
for the case where the detection parameters include fluorescence emission images and/or thermal imaging images,
the step (c) includes: and grading the solar cells by utilizing an automatic optical detection algorithm.
8. The solar cell sorting method according to claim 4,
for the case where the detection parameters include a thermographic image,
the step (c) includes: calculating any one or more of an average temperature of the whole of the solar cell, a maximum temperature of the whole of the solar cell, an average temperature of a specified region in the solar cell, and a maximum temperature of a specified region in the solar cell from the thermal imaging image; and grading the solar cells by using the calculated results.
9. The solar cell sorting method according to claim 4,
for the case where the sensed parameter includes temperature and/or current loading on the battery,
the step (c) includes: and grading the solar battery by using the change of the collected temperature values and/or current values along with time.
10. The solar cell sorting method according to claim 4,
for the case where the sensed parameter includes temperature or current applied to the battery,
the step (c) includes: and selecting the current or the temperature of two fixed points after the duration threshold, calculating the current ratio or the temperature ratio of the two fixed points, and grading the solar cell according to the calculated current ratio or the calculated temperature ratio, wherein the fixed point is a collection point of the target detection parameter, the duration of the application of the reverse external electric field is fixed, and the voltage of the reverse external electric field is also fixed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111034362.9A CN113731865A (en) | 2021-09-03 | 2021-09-03 | Solar cell sorting method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111034362.9A CN113731865A (en) | 2021-09-03 | 2021-09-03 | Solar cell sorting method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113731865A true CN113731865A (en) | 2021-12-03 |
Family
ID=78735723
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111034362.9A Pending CN113731865A (en) | 2021-09-03 | 2021-09-03 | Solar cell sorting method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113731865A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116152195A (en) * | 2023-02-20 | 2023-05-23 | 北京御航智能科技有限公司 | Hot spot detection method and device for photovoltaic cell panel and electronic equipment |
| TWI813515B (en) * | 2022-12-08 | 2023-08-21 | 財團法人工業技術研究院 | Method for detecting hot spot region in a solar cell |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100924491B1 (en) * | 2009-03-27 | 2009-11-03 | (주) 엠브이텍 | Device for inspecting a Solar Cell and Method of the Same |
| US20130333747A1 (en) * | 2012-06-18 | 2013-12-19 | Michael J. Defensor | High current burn-in of solar cells |
| CN103825550A (en) * | 2012-11-19 | 2014-05-28 | 天津永明新能源科技有限公司 | Methods for testing reverse-bias-voltage characteristics of solar-energy cell assembly |
| CN104467663A (en) * | 2014-11-21 | 2015-03-25 | 河海大学常州校区 | System and method for detecting photovoltaic hot spot damage solar cell leak currents |
| CN104506130A (en) * | 2014-11-20 | 2015-04-08 | 晶澳(扬州)太阳能光伏工程有限公司 | PID resistant device for solar photovoltaic component using non-isolated inverter |
| CN105406817A (en) * | 2015-12-04 | 2016-03-16 | 韩华新能源（启东）有限公司 | Method for detecting and determining hot spots of solar cell |
| CN106057702A (en) * | 2016-08-16 | 2016-10-26 | 苏州阿特斯阳光电力科技有限公司 | Detection method for solar battery piece with qualified hot spot temperature range |
| CN107800382A (en) * | 2016-09-05 | 2018-03-13 | 阿特斯阳光电力集团有限公司 | A kind of solar cell test method |
| CN212783490U (en) * | 2020-09-18 | 2021-03-23 | 韩华新能源（启东）有限公司 | Detection device for solar cell after PID performance detection |
-
2021
- 2021-09-03 CN CN202111034362.9A patent/CN113731865A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100924491B1 (en) * | 2009-03-27 | 2009-11-03 | (주) 엠브이텍 | Device for inspecting a Solar Cell and Method of the Same |
| US20130333747A1 (en) * | 2012-06-18 | 2013-12-19 | Michael J. Defensor | High current burn-in of solar cells |
| CN103825550A (en) * | 2012-11-19 | 2014-05-28 | 天津永明新能源科技有限公司 | Methods for testing reverse-bias-voltage characteristics of solar-energy cell assembly |
| CN104506130A (en) * | 2014-11-20 | 2015-04-08 | 晶澳(扬州)太阳能光伏工程有限公司 | PID resistant device for solar photovoltaic component using non-isolated inverter |
| CN104467663A (en) * | 2014-11-21 | 2015-03-25 | 河海大学常州校区 | System and method for detecting photovoltaic hot spot damage solar cell leak currents |
| CN105406817A (en) * | 2015-12-04 | 2016-03-16 | 韩华新能源（启东）有限公司 | Method for detecting and determining hot spots of solar cell |
| CN106057702A (en) * | 2016-08-16 | 2016-10-26 | 苏州阿特斯阳光电力科技有限公司 | Detection method for solar battery piece with qualified hot spot temperature range |
| CN107800382A (en) * | 2016-09-05 | 2018-03-13 | 阿特斯阳光电力集团有限公司 | A kind of solar cell test method |
| CN212783490U (en) * | 2020-09-18 | 2021-03-23 | 韩华新能源（启东）有限公司 | Detection device for solar cell after PID performance detection |
Non-Patent Citations (1)
| Title |
|---|
| 高光渤: "双极性功率晶体管稳定热斑出现过程的研究" * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI813515B (en) * | 2022-12-08 | 2023-08-21 | 財團法人工業技術研究院 | Method for detecting hot spot region in a solar cell |
| CN116152195A (en) * | 2023-02-20 | 2023-05-23 | 北京御航智能科技有限公司 | Hot spot detection method and device for photovoltaic cell panel and electronic equipment |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN113731865A (en) | Solar cell sorting method | |
| TWI609177B (en) | Wafer imaging and processing method and apparatus | |
| JP5051854B2 (en) | Solar cell evaluation method, evaluation apparatus and use thereof | |
| CN106774606B (en) | A kind of global MPPT method and apparatus under uneven illumination is even | |
| JP5243785B2 (en) | Solar cell inspection apparatus and solar cell defect determination method | |
| CN104184413A (en) | Test method and test device of solar cell panel | |
| CN106920496A (en) | The detection method and detection means of display panel | |
| CN109272933A (en) | The method for operating display | |
| CN102089874A (en) | Thin film imaging method and apparatus | |
| Xu et al. | Detection methods for micro-cracked defects of photovoltaic modules based on machine vision | |
| Sulas et al. | Comparison of photovoltaic module luminescence imaging techniques: Assessing the influence of lateral currents in high-efficiency device structures | |
| US20240128793A1 (en) | Power station operation and maintenance system, power station operation and maintenance method, and photovoltaic power station | |
| CN115565902A (en) | Solar cell semi-finished product state evaluation method | |
| CN105676099A (en) | System and method for judging LED device reliability based on electrical properties | |
| CN101858870A (en) | Solar battery electroluminescence image defect detector | |
| CN109781693B (en) | Method and system for monitoring the quality of photovoltaic cells | |
| US8841928B2 (en) | Organic EL panel inspection method, organic EL panel inspection device, and organic EL panel | |
| US20230335668A1 (en) | Method for improving the ohmic contact behavior between a contact grid and an emitter layer of a silicon solar cell | |
| CN101915546B (en) | Solar chip anti-reflection coating detection method and detection device thereof | |
| Berardone et al. | Quantitative analysis of electroluminescence and infrared thermal images for aged monocrystalline silicon photovoltaic modules | |
| CN111681616A (en) | MiniLED backlight display device, backlight module and brightness compensation method | |
| CN201673125U (en) | Solar battery electroluminescence image defect detector | |
| Höffler et al. | Statistical Evaluation of a Luminescence-based Method for imaging the series resistance of solar cells | |
| Johnston et al. | Imaging study of multi-crystalline silicon wafers throughout the manufacturing process | |
| CN212379284U (en) | Device for improving defect detection capability of electroluminescent equipment on solar cell |
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 |