Battery piece conversion efficiency detection method and device

Abstract

The invention provides a battery piece conversion efficiency detection method and equipment, relates to the field of semiconductor or photovoltaic material detection, and solves the technical problem of how to detect the texturing surface of a battery piece and the process quality and contact performance of different film layers before silk-screen printing. The battery piece conversion efficiency detection method comprises the following steps: performing contact angle detection on a target sheet-shaped material, and determining a target contact angle of the target sheet-shaped material; obtaining target classification information of the target sheet material; determining a target contact angle standard range corresponding to the target classification information based on a pre-established corresponding relationship between preset classification information and a preset contact angle standard range; and determining a battery conversion efficiency detection result of the target sheet material based on the target contact angle and the target contact angle standard range. In this way, the target flaky material can be detected before silk-screen printing is carried out, so that the unqualified flaky material is not subjected to subsequent silk-screen printing treatment, and the production cost is saved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor or photovoltaic material detection, and specifically to a method and device for detecting conversion efficiency of a cell. Background Art

[0002] In the photovoltaic field, transparent conductive oxide (TCO) film layers are widely used in different battery technologies, mainly in heterojunction technology. TCO film layers are mainly used as carrier lateral transport layers, anti-reflection layers and buffer layers. The main methods for preparing TCO film layers are magnetron sputtering deposition (Sputter) and reaction plasma deposition (RPD). Their advantages are fast deposition speed, high film purity, good uniformity and good bonding with the substrate. In the production process of heterojunction batteries, the process quality and contact performance of the textured surface and different film layers have a great influence on the conversion efficiency of the battery cell, such as the size and angle of the textured surface pyramid, the thickness and quality of the chemical vapor deposition (CVD) film layer, the thickness and quality of the TCO film layer, the contact performance between the TCO film layer and the silver paste, the contact performance between the CVD film layer and the TCO film layer, etc. Among them, the contact performance between the TCO film layer and the silver paste directly affects the extraction effect of the current collected by the battery, thereby affecting the conversion efficiency of the battery. Therefore, testing the contact performance between the TCO film layer and the silver paste has become an important means of performance inspection in the battery production process.

[0003] In the related art, the following two methods are usually used to detect the quality of the battery cell film layer. First, the processed battery cells are tested by the IV tester on the battery cell processing production line. Specifically, the battery conversion efficiency (Eff), the series resistance (Rs) and the parallel resistance (Rsh) of the battery cell can be tested by the IV tester. The second is to slice the battery cells after screen printing, and then use a contact resistance tester (Transmission Line Model, TLM) to measure the contact resistance. However, both of these detection methods require the battery cells to be tested after screen printing. If there is a problem with the quality of any of the TCO film layer, CVD film layer or velvet surface pyramid of a batch of battery cells, the batch of battery cells can only be detected after screen printing with silver paste, wasting a lot of silver paste. Therefore, how to detect the process quality and contact performance of the velvet surface and different film layers of the battery cell before screen printing has become an urgent problem to be solved. Summary of the invention

[0004] In order to solve the above technical problems, the present application is proposed. The embodiments of the present application provide a method and device for detecting conversion efficiency of a battery cell.

[0005] In a first aspect, an embodiment of the present application provides a method for detecting battery cell conversion efficiency, comprising: performing contact angle detection on a target sheet material to determine a target contact angle of the target sheet material; obtaining target classification information of the target sheet material, wherein the target classification information is determined based on at least one surface property of the target sheet material; determining a target contact angle standard range corresponding to the target classification information based on a pre-established correspondence between preset classification information and a preset contact angle standard range; and determining a battery conversion efficiency detection result of the target sheet material based on the target contact angle and the target contact angle standard range.

[0006] In some embodiments, before determining the target contact angle standard range corresponding to the target classification information based on a pre-established correspondence between preset classification information and a preset contact angle standard range, the method also includes: obtaining multiple test sheet materials, the classification information of the multiple test sheet materials is different; determining the contact angles of the multiple test sheet materials; determining the battery conversion efficiency of battery cells made of the multiple test sheet materials; determining the test sheet materials that meet the standard battery conversion efficiency range based on the standard battery conversion efficiency range and the battery conversion efficiency of the battery cells made of the multiple test sheet materials; establishing a correspondence between the preset classification information and the preset contact angle standard range based on the contact angle of the test sheet material that meets the standard battery conversion efficiency range and the classification information of the test sheet material that meets the standard battery conversion efficiency range.

[0007] In some embodiments, before performing contact angle detection on the target sheet material, the method further includes: transporting the sheet material in batches according to classification information, the classification information corresponding to each batch of sheet materials is the same; randomly sampling a batch of sheet materials to be transported and tested from the sheet materials transported in batches, and using the sheet materials to be transported and tested as the target sheet material.

[0008] In some embodiments, the surface properties of the target sheet material include at least one of the following: an average size of textured surface pyramids, a type of chemical vapor deposition film layer, and a type of transparent conductive oxide film layer target material.

[0009] In some embodiments, the average size range of the textured surface pyramids is 1 micron to 3 microns, the chemical vapor deposition film layer types include amorphous and microcrystalline, and the transparent conductive oxide film layer target material type includes a target material containing indium oxide and at least one other oxide except indium oxide, wherein different target materials contain different ratios of indium oxide to at least one other oxide except indium oxide.

[0010] In some embodiments, if the average size of the velvet surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, the target contact angle standard range of the target sheet material is 10 degrees to 13 degrees; if the average size of the velvet surface pyramids of the target sheet material is 1.5 microns to 1.9 microns, the target contact angle standard range of the target sheet material is 7.5 degrees to 10 degrees.

[0011] In some embodiments, if the average size of the textured surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, and the chemical vapor deposition film type is amorphous, then the target contact angle standard range of the target sheet material is 11 degrees to 13 degrees; if the average size of the textured surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, and the chemical vapor deposition film type is microcrystalline, then the target contact angle standard range of the target sheet material is 11 degrees to 12.5 degrees.

[0012] In the second aspect, an embodiment of the present application provides a battery cell conversion efficiency detection device, comprising: a coating device, configured to coat sheet materials, the coated sheet materials passing through a feed area of ​​the coating device; a first conveying device, the first conveying device configured to take away and transport target sheet materials from each batch of coated sheet materials in the feed area, or the first conveying device configured to take away and transport target sheet materials from the coated sheet materials in the feed area at preset time intervals; a testing device, disposed above the feed area or to the side of the feed area, configured to receive the target sheet materials conveyed by the first conveying device, and determine the battery conversion efficiency detection result of the target sheet material based on any of the battery cell conversion efficiency detection methods of the first aspect above.

[0013] In some embodiments, the testing device includes: a testing platform, arranged above the unloading area or to the side of the unloading area, configured to receive and carry the target sheet material transported by the first conveying device; a dripping unit, arranged on the testing platform, configured to drip the test liquid on the surface of the target sheet material; an image acquisition device, arranged on the testing platform, configured to photograph the test liquid on the surface of the target sheet material, obtain and transmit the test image; an analysis device, communicatively connected to the image acquisition device, configured to receive the test image transmitted by the image acquisition device, and determine the battery conversion efficiency detection result of the target sheet material based on the battery cell conversion efficiency detection method and the test image.

[0014] In some embodiments, the battery cell conversion efficiency testing equipment also includes: a second conveying device, configured to take away and transport the target sheet material after testing in the testing device; a waste sheet box, arranged on one side of the unloading area, configured to receive the target sheet material transported by the second conveying device; and / or, the battery cell conversion efficiency testing equipment also includes: a screen printing device, configured to perform screen printing processing on sheet materials other than the target sheet material from the same batch as the target sheet material when the battery conversion efficiency test result of the target sheet material is qualified.

[0015] The method for detecting the conversion efficiency of a battery cell proposed in the embodiment of the present application, first, because the process quality and contact performance of the velvet surface pyramid and different film layers will affect the target contact angle of the target sheet material, and the contact performance between the film layer of the target sheet material and the screen-printed silver paste in the subsequent process directly affects the conversion efficiency of the battery cell made of the target sheet material, therefore, through this method, the target contact angle of the target sheet material is first detected, and then the battery conversion efficiency detection result of the target sheet material is determined according to the target contact angle of the target sheet material. The battery conversion efficiency detection result can accurately reflect whether the process quality and contact performance of the velvet surface pyramid and different film layers meet the standards, and whether the battery conversion efficiency of the battery cell made of the target sheet material meets the standards. Second, the method for detecting the conversion efficiency of a battery cell proposed in the embodiment of the present application has a fast detection speed, and can be applied to online detection of sheet materials in the production process, providing a reliable basis for the normal flow between product processes. Third, the cell conversion efficiency detection method proposed in the embodiment of the present application can detect the target sheet material before using silver paste for screen printing, so that sheet materials other than the target sheet material that do not meet the quality standards and are from the same batch as the target sheet material can be exempted from subsequent screen printing processing, thereby reducing the waste of silver paste and saving production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] By describing the embodiments of the present application in more detail in conjunction with the accompanying drawings, the above and other purposes, features and advantages of the present application will become more apparent. The accompanying drawings are used to provide a further understanding of the embodiments of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation of the present application. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0017] Figure 1 The figure is a schematic flow chart of a method for detecting conversion efficiency of a cell provided by an exemplary embodiment of the present application.

[0018] Figure 2 It is a schematic flow chart of a method for establishing a correspondence between preset classification information and a preset contact angle standard range provided by an exemplary embodiment of the present application.

[0019] Figure 3 Shown is a schematic structural diagram of a battery cell conversion efficiency detection device provided by an exemplary embodiment of the present application.

[0020] Figure 4 Shown is a schematic structural diagram of a battery cell conversion efficiency detection device provided by another exemplary embodiment of the present application.

[0021] Figure 5 Shown is a schematic structural diagram of a testing device provided by an exemplary embodiment of the present application.

[0022] Reference numerals:

[0023] 300, battery cell conversion efficiency testing equipment; 310, coating device; 311, unloading area; 3111, third conveying device; 312, loading area; 313, processing area; 320, testing device; 321, testing platform; 322, dripping unit; 323, image acquisition device; 324, analysis device; 330, waste film box. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0025] Figure 1 FIG. 1 is a flow chart of a method for detecting conversion efficiency of a cell provided by an exemplary embodiment of the present application. Figure 1 As shown, an embodiment of the present application provides a method for detecting conversion efficiency of a battery cell. The method for detecting conversion efficiency of a battery cell provided by the embodiment of the present application includes the following steps 101 to 104 .

[0026] Step 101: Perform contact angle detection on a target sheet material to determine a target contact angle of the target sheet material.

[0027] Wherein, the target sheet material can be exemplarily a sheet of a batch of sheet materials to be tested, and the sheet material is used to make a photovoltaic cell, and the photovoltaic cell can be exemplarily a heterojunction cell, a tunnel oxide passivated contact (Tunnel Oxide Passivated Contact, TOPCon) cell, or a back contact (Back Contact, BC) cell. The target sheet material includes a substrate (such as a silicon wafer) and at least one film layer. For example, the target sheet material used to make a heterojunction cell has a TCO film layer and a CVD film layer. The target contact angle of the target sheet material is the contact angle of the surface film layer of the target sheet material before the screen printing process. If the target sheet material is used to make a heterojunction cell, the surface film layer of the target sheet material is a TCO film layer. In the following content, the embodiments of the present application are described by taking the use of the target sheet material to make a heterojunction cell as an example.

[0028] In some embodiments, when performing contact angle detection on a target sheet material to determine a target contact angle of the target sheet material, a test liquid can be first dropped onto the target sheet material, and then the test liquid on the surface of the target sheet material is photographed to obtain a test image, and finally an analysis device determines the target contact angle of the target sheet material based on the test image.

[0029] Step 102: Obtain target classification information of the target sheet material.

[0030] The target classification information is determined based on at least one surface property of the target sheet material. Specifically, each sheet material has its corresponding classification information, and the classification information may correspond to at least one surface property, and the classification information may also be used as a batch number when a batch of sheet materials is processed. The surface property may include, for example, the material and / or grain type (such as microcrystalline and amorphous) of at least one film layer of the target sheet material, and the size of the pile surface pyramid of the target sheet material.

[0031] In some embodiments, the surface properties of the target sheet material include at least one of the following: average textured pyramid size, chemical vapor deposition film type (referred to as CVD film type), transparent conductive oxide film target type (referred to as TCO film target type).

[0032] Specifically, a CVD film layer and a TCO film layer are sequentially arranged above the textured surface. Since the textured surface has a pyramid shape, the CVD film layer and the TCO film layer arranged on the upper layer of the textured surface will also form a pyramid shape. Gaps for filling silver paste are formed between the pyramids of the TCO film layer. Therefore, the size of the textured surface pyramid will directly affect the filling effect of silver paste of different particle sizes in the gaps of the TCO film layer. When the average particle size of the silver powder of the silver paste is large, if the average size of the textured surface pyramid is large, the filling effect of the silver paste with the large-size pyramid is better and the contact area is larger. If the average size of the textured surface pyramid is small, the filling effect of the silver paste with the small-size pyramid is poor and the contact area is smaller, thereby affecting the electrical performance of the battery cell. Therefore, the average size of the textured surface pyramid is one of the properties that affect the contact angle of the target sheet material and the conversion efficiency of the battery cell.

[0033] In addition, the electrical properties of CVD films and TCO films of different materials are quite different. The grain types of CVD films are microcrystalline and amorphous. The indium tin oxide (ITO) target in the TCO film has a variety of different ratios, and the carrier mobility and carrier concentration sputtered from different CVD films are different. When matching CVD films and TCO films, it is necessary to consider the matching of work functions, so different ITO targets should be selected for TCO films according to different CVD films. Therefore, when using different CVD films and TCO films, the surface grain size and morphology of different CVD films and TCO films will affect the size of the contact angle of the target sheet material, and the thickness of the CVD film and TCO film will also affect the size of the gap between the pyramids of the TCO film, thereby affecting the size of the contact angle of the target sheet material.

[0034] In some embodiments, the average size range of the textured surface pyramids is 1 micron to 3 microns, the chemical vapor deposition film type (i.e., the above-mentioned grain type) includes amorphous and microcrystalline, and the transparent conductive oxide film target type (such as ITO target) includes a target containing indium oxide and at least one other oxide other than indium oxide (such as tin oxide, cerium oxide, gallium oxide, cadmium oxide), wherein different targets contain different ratios of indium oxide to at least one other oxide other than indium oxide.

[0035] Exemplarily, the ratio of indium oxide to at least one other oxide other than indium oxide in the ITO target can be 90:10, 95:5, 97:3, 99:1. The common combination of CVD film layer and TCO film layer at present is: the amorphous CVD film layer is combined with a TCO film layer including an ITO target material (referred to as 9010 target material) containing indium oxide and at least one other oxide other than indium oxide in a ratio of 90:10, and the microcrystalline CVD film layer is combined with a TCO film layer including an ITO target material (referred to as 991 target material) containing indium oxide and at least one other oxide other than indium oxide in a ratio of 99:1.

[0036] Step 103: Determine a target contact angle standard range corresponding to the target classification information based on a pre-established correspondence relationship between preset classification information and preset contact angle standard range.

[0037] Among them, for any preset contact angle standard range corresponding to the preset classification information, the preset contact angle standard range is used to characterize: when the conversion efficiency of the battery cell made of the sheet material corresponding to the preset classification information is within the standard battery conversion efficiency range, the contact angle range of the sheet material corresponding to the preset classification information. Exemplarily, the contact angle range of the sheet material is usually 8 degrees to 12 degrees. If the surface attribute corresponding to the preset classification information is the average size of the velvet surface pyramid, the preset contact angle standard range corresponding to the preset classification information of the average size of the large velvet surface pyramid is usually 10 degrees to 12 degrees, and the preset contact angle standard range corresponding to the preset classification information of the average size of the small velvet surface pyramid is usually 8 degrees to 10 degrees.

[0038] In some embodiments, if the average size of the velvet surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, the target contact angle standard range of the target sheet material is 10 degrees to 13 degrees; if the average size of the velvet surface pyramids of the target sheet material is 1.5 microns to 1.9 microns, the target contact angle standard range of the target sheet material is 7.5 degrees to 10 degrees.

[0039] The target contact angle standard range of the target sheet material is: the target contact angle standard range corresponding to the target classification information of the target sheet material. Since the average size of the velvet surface pyramid is one of the important factors affecting the contact angle of the sheet material, the target contact angle standard range of the target sheet material can be accurately determined by determining the average size of the velvet surface pyramid of the target sheet material.

[0040] In some embodiments, if the average size of the textured surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, and the chemical vapor deposition film type is amorphous, then the target contact angle standard range of the target sheet material is 11 degrees to 13 degrees; if the average size of the textured surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, and the chemical vapor deposition film type is microcrystalline, then the target contact angle standard range of the target sheet material is 11 degrees to 12.5 degrees.

[0041] Among them, the target contact angle standard range of the target sheet material is: the target contact angle standard range corresponding to the target classification information of the target sheet material. Since the average size of the textured surface pyramids and the type of chemical vapor deposition film are important factors affecting the contact angle of the sheet material, by determining the average size of the textured surface pyramids and the type of chemical vapor deposition film of the target sheet material, the target contact angle standard range of the target sheet material can be accurately determined.

[0042] Step 104: Determine a battery conversion efficiency test result of a target sheet material based on the target contact angle and the target contact angle standard range.

[0043] Specifically, if the target contact angle is within the target contact angle standard range, the battery conversion efficiency test result of the target sheet material is qualified (which can be expressed as the target sheet material is an OK sheet); if the target contact angle is outside the target contact angle standard range, the battery conversion efficiency test result of the target sheet material is unqualified (which can be expressed as the target sheet material is an NG sheet).

[0044] Figure 2 It is a schematic flow chart of a method for establishing a correspondence between preset classification information and a preset contact angle standard range provided by an exemplary embodiment of the present application.

[0045] In some embodiments, Figure 2 As shown, before determining the target contact angle standard range corresponding to the target classification information based on the pre-established correspondence between the preset classification information and the preset contact angle standard range, the correspondence between the preset classification information and the preset contact angle standard range can be established based on the following steps 201 to 205.

[0046] Step 201: Acquire multiple test sheet materials, where the classification information of the multiple test sheet materials is different.

[0047] Step 202: Determine the contact angles of a plurality of test sheet materials.

[0048] Step 203: Determine the battery conversion efficiency of the battery cells made of a plurality of test sheet materials.

[0049] Step 204 : Based on the standard battery conversion efficiency range and the battery conversion efficiencies of battery cells made of a plurality of test sheet materials, determine a test sheet material that meets the standard battery conversion efficiency range.

[0050] Step 205 : Based on the contact angle of the test sheet material that meets the standard battery conversion efficiency range and the classification information of the test sheet material that meets the standard battery conversion efficiency range, a corresponding relationship between the preset classification information and the preset contact angle standard range is established.

[0051] Exemplarily, the correspondence between the preset classification information, surface properties, preset contact angle standard range, standard battery conversion efficiency range, target contact angle of unqualified target sheet material and battery conversion efficiency corresponding to the target contact angle of unqualified target sheet material is shown in Table 1 below. Among them, the surface properties include the average size of the textured surface pyramid, the CVD film type and the TCO film target type, Eff1% represents the standard battery conversion efficiency range, and Eff2% represents the battery conversion efficiency corresponding to the target contact angle of the unqualified target sheet material. Table 1 is a corresponding relationship table of battery conversion efficiency.

[0052] Table 1 Corresponding relationship table of battery conversion efficiency

[0053]

[0054] Through this method, the preset contact angle standard range corresponding to each preset classification information can be accurately established, so that the preset contact angle standard range corresponding to each preset classification information can be characterized: when the conversion efficiency of a battery cell made of a sheet material corresponding to the preset classification information is within the standard battery conversion efficiency range, the range of the contact angle of the sheet material corresponding to the classification information, thereby through the detection of the target contact angle of the target sheet material, the quality of the battery cell made of the target sheet material can be accurately estimated.

[0055] In some embodiments, before performing contact angle detection on the target sheet material, the sheet material can be transported in batches according to classification information, wherein the classification information corresponding to each batch of sheet materials is the same; then, a batch of sheet materials to be transported are randomly selected from the sheet materials transported in batches, and the sheet materials to be transported are used as the target sheet material.

[0056] Specifically, the classification information of each batch of sheet materials is the batch number of each batch of sheet materials, and the classification information corresponding to each batch of sheet materials is the same. Therefore, when a batch of sheet materials to be transported is sampled, at least one sheet material in the batch of sheet materials to be transported can be selected as the target sheet material.

[0057] In some embodiments, when sampling a batch of transported sheet materials to be inspected from sheet materials transported in batches, each batch of sheet materials can be treated as a batch of transported sheet materials to be inspected, that is, target sheet materials are extracted from each batch of sheet materials for inspection; or, at every preset time interval, a batch of sheet materials currently being transported or processed can be treated as a batch of transported sheet materials to be inspected, that is, target sheet materials are extracted for inspection at every preset time interval.

[0058] The method for detecting the conversion efficiency of a cell proposed in the embodiment of the present application, first, because the process quality and contact performance of the velvet surface pyramid and different film layers will affect the target contact angle of the target sheet material, and the contact performance between the film layer of the target sheet material and the screen-printed silver paste in the subsequent process directly affects the conversion efficiency of the cell made of the target sheet material, therefore, through this method, the target contact angle of the target sheet material is first detected, and then the cell conversion efficiency detection result of the target sheet material is determined according to the target contact angle of the target sheet material, and the cell conversion efficiency detection result accurately reflects whether the process quality and contact performance of the velvet surface pyramid and different film layers meet the standards (for heterojunction cells, especially reflects the contact performance of the TCO film layer and the silver paste), and whether the cell conversion efficiency of the cell made of the target sheet material meets the standards. Second, the method for detecting the conversion efficiency of a cell proposed in the embodiment of the present application has a fast detection speed, and can be applied to online detection of sheet materials in the production process, providing a reliable basis for the normal flow between product processes. Third, the cell conversion efficiency detection method proposed in the embodiment of the present application can detect the target sheet material before using silver paste for screen printing, so that sheet materials other than the target sheet material that do not meet the quality standards and are from the same batch as the target sheet material can be exempted from subsequent screen printing processing, thereby reducing the waste of silver paste and saving production costs.

[0059] Figure 3 FIG. 1 is a schematic diagram of a battery conversion efficiency detection device provided by an exemplary embodiment of the present application. Figure 4 Shown is a schematic structural diagram of a battery cell conversion efficiency detection device provided by another exemplary embodiment of the present application.

[0060] Based on the same inventive concept, Figure 3 and Figure 4As shown, the embodiment of the present application also provides a battery conversion efficiency detection device 300, which includes a coating device 310, a first conveying device and a testing device 320. The coating device 310 is configured to coat the sheet material, and the coated sheet material passes through the unloading area 311 of the coating device 310; the first conveying device is configured to take and transport the target sheet material from each batch of coated sheet materials in the unloading area 311, or the first conveying device is configured to take and transport the target sheet material from the coated sheet material in the unloading area 311 at a preset time interval; the testing device 320 is arranged above the unloading area 311 or on the side of the unloading area 311, and is configured to receive the target sheet material conveyed by the first conveying device, and determine the battery conversion efficiency detection result of the target sheet material based on any of the battery conversion efficiency detection methods of the above embodiments.

[0061] The coating device 310 may include a loading area 312, a processing area 313 and a unloading area 311. The processing area 313 is arranged between the loading area 312 and the unloading area 311. The unloading area 311 may have a film taking platform or a third conveying device 3111. The third conveying device 3111 is exemplarily a conveyor belt. The first conveying device may be a mechanical gripper or a conveyor belt.

[0062] In actual applications, the sheet material first enters the loading area 312 for loading, and then is coated in the processing area 313. The coated sheet material enters the unloading area 311 and is transported by the third conveying device 3111. The first conveying device takes at least one piece of target sheet material from the third conveying device 3111 and places it on the testing device 320. Then the testing device 320 can detect at least one piece of target sheet material based on any of the battery cell conversion efficiency detection methods of the above embodiments.

[0063] Through this structure, during the production process of the battery cell, the target sheet material can be automatically extracted to perform battery cell conversion efficiency testing, thereby achieving online testing of the target sheet material.

[0064] Figure 5 Shown is a schematic structural diagram of a testing device provided by an exemplary embodiment of the present application.

[0065] In some embodiments, Figure 5As shown, the test device 320 includes a test platform 321, a dripping unit 322 (such as an injection needle), an image acquisition device 323 (such as an autofocus camera unit) and an analysis device 324. The test platform 321 is arranged above the unloading area 311 or on the side of the unloading area 311, and is configured to receive and carry the target sheet material transported by the first conveying device; the dripping unit 322 is arranged on the test platform 321, and is configured to drip the test liquid (such as ethylene glycol) on the surface of the target sheet material; the image acquisition device 323 is arranged on the test platform 321, and is configured to shoot the test liquid on the surface of the target sheet material, obtain and transmit the test image; the analysis device 324 is connected to the image acquisition device 323 in communication, and is configured to receive the test image transmitted by the image acquisition device 323, and determine the battery conversion efficiency detection result of the target sheet material based on the battery conversion efficiency detection method and the test image.

[0066] In actual application, the first conveying device places the target sheet material on the contact angle test area on the test platform 321, and the dripping unit 322 drips a certain amount of test liquid onto the target sheet material. The image acquisition device 323 automatically focuses and photographs the test liquid on the surface of the target sheet material to obtain a test image, and sends the test image to the analysis device 324. The analysis device 324 determines the target contact angle of the target sheet material based on the received test image, and based on the target contact angle of the target sheet material, detects the battery conversion efficiency test result of the target sheet material.

[0067] In some embodiments, the battery cell conversion efficiency detection device 300 further includes a second conveying device and a waste film box 330. The second conveying device is configured to take away and transport the target sheet material after testing in the testing device 320; the waste film box 330 is arranged on one side of the unloading area 311, and is configured to receive the target sheet material transported by the second conveying device. Among them, the second conveying device is exemplarily a mechanical gripper, and the second conveying device can be the same conveying device as the first conveying device, or the second conveying device is a conveying device other than the first conveying device. By providing the second conveying device and the waste film box 330, the contaminated target sheet material after testing can be stored.

[0068] In some embodiments, the cell conversion efficiency testing device 300 further includes a screen printing device, which is configured to perform screen printing processing on sheet materials other than the target sheet material from the same batch as the target sheet material when the cell conversion efficiency test result of the target sheet material is qualified, that is, when the cell conversion efficiency test result of the target sheet material is qualified, other sheet materials from the same batch as the target sheet material generally have substantially the same processing quality, so that subsequent screen printing processing procedures can be performed. The screen printing device can illustratively process the sheet material using silver paste.

[0069] In some embodiments, when the battery conversion efficiency test result of the target sheet material is unqualified, the processing flow of sheet materials other than the target sheet material from the same batch as the target sheet material can be terminated (i.e., the processing flow using the screen printing equipment for processing is stopped), and the processing process of the batch of sheet materials, the processing quality of each layer of the film, and the processing quality of the velvet surface are checked to determine the reason for the poor processing quality of the batch of sheet materials.

[0070] The basic principles of the present application are described above in conjunction with specific embodiments. However, it should be noted that the advantages, strengths, effects, etc. mentioned in the present application are only examples and not limitations, and it cannot be considered that these advantages, strengths, effects, etc. are required by each embodiment of the present application. In addition, the specific details disclosed above are only for the purpose of illustration and ease of understanding, not for limitation, and the above details do not limit the present application to being implemented by adopting the above specific details.

[0071] The block diagrams of the devices, apparatuses, equipment, and systems involved in this application are only illustrative examples and are not intended to require or imply that they must be connected, arranged, and configured in the manner shown in the block diagram. As will be appreciated by those skilled in the art, these devices, apparatuses, equipment, and systems can be connected, arranged, and configured in any manner. Words such as "including", "comprising", "having", etc. are open words, referring to "including but not limited to", and can be used interchangeably with them. The words "or" and "and" used here refer to the words "and / or" and can be used interchangeably with them, unless the context clearly indicates otherwise. The words "such as" used here refer to the phrase "such as but not limited to", and can be used interchangeably with them.

[0072] It should also be noted that in the apparatus, device and method of the present application, each component or each step can be decomposed and / or recombined. Such decomposition and / or recombination should be regarded as equivalent solutions of the present application.

[0073] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of the present application. Therefore, the present application is not intended to be limited to the aspects shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

[0074] The above description has been given for the purpose of illustration and description. In addition, this description is not intended to limit the embodiments of the present application to the forms disclosed herein. Although multiple example aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, changes, additions and sub-combinations thereof.

Claims

1. A method for detecting conversion efficiency of a battery cell, characterized in that: include: Performing contact angle detection on a target sheet material to determine a target contact angle of the target sheet material; Acquiring target classification information of the target sheet material, wherein the target classification information is determined based on at least one surface property of the target sheet material; Determining a target contact angle standard range corresponding to the target classification information based on a pre-established correspondence between preset classification information and preset contact angle standard range; Based on the target contact angle and the target contact angle standard range, a battery conversion efficiency test result of the target sheet material is determined.

2. The method for detecting conversion efficiency of a battery cell according to claim 1, characterized in that: Before determining the target contact angle standard range corresponding to the target classification information based on the pre-established correspondence between the preset classification information and the preset contact angle standard range, the method further includes: Acquire a plurality of test sheet materials, wherein the classification information of the plurality of test sheet materials is different; determining contact angles of a plurality of said test sheet materials; Determining the battery conversion efficiency of a battery cell made of a plurality of the test sheet materials; Based on a standard battery conversion efficiency range and battery conversion efficiencies of battery cells made of a plurality of the test sheet materials, determining the test sheet material that meets the standard battery conversion efficiency range; Based on the contact angle of the test sheet material that meets the standard battery conversion efficiency range and the classification information of the test sheet material that meets the standard battery conversion efficiency range, a corresponding relationship between the preset classification information and the preset contact angle standard range is established.

3. The method for detecting conversion efficiency of a battery cell according to claim 1 or 2, characterized in that: Before the contact angle detection of the target sheet material, the method further comprises: Transporting the sheet materials in batches according to the classification information, the classification information corresponding to each batch of the sheet materials being the same; A batch of transported sheet materials to be inspected is randomly selected from the sheet materials transported in batches, and the transported sheet materials to be inspected are used as the target sheet materials.

4. The method for detecting conversion efficiency of a battery cell according to claim 1 or 2, characterized in that: The surface properties of the target sheet material include at least one of the following: Average size of textured pyramids, chemical vapor deposition film type, and transparent conductive oxide film target type.

5. The method for detecting conversion efficiency of a cell according to claim 4, characterized in that: The average size range of the textured surface pyramids is 1 micron to 3 microns, the chemical vapor deposition film layer types include amorphous and microcrystalline, and the transparent conductive oxide film layer target material type includes a target material containing indium oxide and at least one other oxide except indium oxide, wherein different target materials contain different ratios of indium oxide to at least one other oxide except indium oxide.

6. The method for detecting conversion efficiency of a cell according to claim 4, characterized in that: If the average size of the textured surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, the target contact angle standard range of the target sheet material is 10 degrees to 13 degrees; If the average size of the textured surface pyramids of the target sheet material is 1.5 micrometers to 1.9 micrometers, the target contact angle standard range of the target sheet material is 7.5 degrees to 10 degrees.

7. The method for detecting conversion efficiency of a battery cell according to claim 4, characterized in that: If the average size of the textured surface pyramids of the target sheet material is 2.0 microns to 2.5 microns, and the chemical vapor deposition film type is amorphous, then the target contact angle standard range of the target sheet material is 11 degrees to 13 degrees; If the average size of the textured surface pyramids of the target sheet material is 2.0 micrometers to 2.5 micrometers, and the chemical vapor deposition film layer is microcrystalline, then the target contact angle standard range of the target sheet material is 11 degrees to 12.5 degrees.

8. A battery conversion efficiency detection device, characterized in that: include: A coating device, configured to coat a sheet material, wherein the coated sheet material passes through a material unloading area of ​​the coating device; A first conveying device, wherein the first conveying device is configured to take and transport the target sheet material from each batch of the sheet material after coating in the unloading area, or the first conveying device is configured to take and transport the target sheet material from the sheet material after coating in the unloading area at a preset time interval; The testing device is arranged above the unloading area or on the side of the unloading area, and is configured to receive the target sheet material conveyed by the first conveying device, and determine the battery conversion efficiency detection result of the target sheet material based on the battery cell conversion efficiency detection method described in any one of claims 1 to 7 above.

9. The battery conversion efficiency detection device according to claim 8, characterized in that: The testing device comprises: A test platform, disposed above the unloading area or to the side of the unloading area, configured to receive and carry the target sheet material conveyed by the first conveying device; a liquid dropping unit, disposed on the test platform and configured to drop a test liquid on the surface of the target sheet material; An image acquisition device, disposed on the test platform, configured to photograph the test liquid on the surface of the target sheet material to obtain and transmit a test image; The analyzing device is communicatively connected to the image acquisition device and is configured to receive the test image transmitted by the image acquisition device and determine the battery conversion efficiency detection result of the target sheet material based on the battery cell conversion efficiency detection method and the test image.

10. The battery conversion efficiency detection device according to claim 8 or 9, characterized in that: The battery conversion efficiency detection device also includes: a second conveying device, configured to take away and transport the target sheet material after being tested in the testing device; a waste sheet box, disposed at one side of the unloading area, and configured to receive the target sheet material transported by the second conveying device; and / or, The battery conversion efficiency detection device also includes: The screen printing device is configured to perform screen printing processing on the sheet material other than the target sheet material from the same batch as the target sheet material when a battery conversion efficiency test result of the target sheet material is qualified.

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