TBC battery and preparation method thereof

Abstract

The invention relates to the field of Topcon battery manufacturing processes, in particular to a TBC battery and a preparation method thereof. The preparation method of the TBC battery is characterized by comprising the following steps: preorder steps; a screen plate is improved, a silk-screen printing technology is adopted, mask printing is carried out on the electroplated battery piece, the specification of the screen plate is reduced, grid lines are widened, and an anti-sticking coating film is additionally arranged at the bottom of the screen plate; the drying mode is improved, the battery pieces are dried and printed through a curing oven, hot air drying is adopted, and low-temperature long-time curing air drying is adopted; the Mark point capturing mode is improved, a camera is arranged over the battery piece, and auxiliary lamplight is additionally arranged on the two sides of the battery piece; and subsequent steps. According to the invention, the cost is reduced, the one-time forming effect is improved, the adsorption problem is solved, the battery warping degree is reduced, the productivity is high, the temperature time control is flexible, the grabbing point deviation is solved, the grabbing point accuracy is improved, and the economic benefit, the product quality, the process stability and the automatic transmission suitability of BC battery production are improved.

Description

Technical Field

[0001] The invention relates to the field of Topcon battery manufacturing technology, and designs a TBC battery and a preparation method thereof. Background Art

[0002] Photovoltaic power generation has become an important support for realizing the energy transformation strategy. Huge innovation investment has helped to promote the continuous increase in the efficiency of solar cells. N-type Topcon cells have been widely used due to their low attenuation, overall efficiency and power generation, and have become the mainstream product in the market. With the increasing demand for photovoltaics in recent years and the rapid iterative development of photovoltaic technology, how to improve the conversion efficiency of crystalline silicon solar cells and reduce costs has become a key factor in realizing photovoltaic power generation. A new technology platform has emerged (Interdigitated Back Contact, IBC) N-type interdigitated back contact cell. Back contact cells have no photoinduced degradation and high conversion efficiency, and have become the focus of current research. In order to further improve the conversion efficiency of the cell, the TOPCon (tunneling silicon oxide / doped polysilicon) + BC (full back contact) = TBC (Tunnel Back Contact) technology route is combined.

[0003] In the existing printing technology, the printing method generally adopts the method of segmented printing with main / fine grid line separation, and the curing method is to connect the drying furnace and the printing machine to each other. Therefore, more printing machines and drying furnaces are used, and the equipment cost and occupied area are large. There are the following problems: (1) Conventional silver paste printing requires higher screen specifications and higher printing quality requirements, and the screen cost is also relatively high. The disadvantage of ink as a mask material is that it has a high viscosity and is easy to stick to the screen during printing; (2) The battery warpage is too high during the drying process. Since the battery cell adopts the method of full-surface electroplating, the thickness of the electroplated copper is about 4-5μm, and the thickness of the electroplated tin is about 2-3μm. The length of the conventional oven is about 3.5-4 meters, and the length from drying to output is about 1.5-2.5 meters. The time for printing is about 12-15 seconds, and the drying temperature is about 260° to 320°. The main method is to use lamp heating to dry the cells in a short time at high temperature. After the electroplated cells are heated and contracted in a conventional drying furnace, the curvature reaches 4-5 mm. The curvature of the cells is too high, so the automation cannot directly transfer the materials. In addition, the drying time is too short, and the internal components of the ink are not completely volatilized, which cannot achieve the acid and corrosion resistance of the mask ink material during the etching process; (3) The point grabbing accuracy is too low during the printing process. BC cells are currently mainly formed on the back of the silicon wafer by graphic laser dry etching process. The forked P-type and N-type regions are formed. This is one of the key steps to achieve back contact (wet etching can also be used to achieve this step). The width of the N / P region graphic design is about 560-620μm. The cross-sectional design of the P region of the N-type substrate cell can be wider than the cross-sectional design of the N region. The laser uses a purple / green picosecond square large spot to scan and remove B / PSG and excess Poly layer. The Mark point also completes the process steps while the laser is patterned twice. The Mark point on the battery cell appears as a concave rectangular small square after the laser process. During the printing process, the printing accuracy of the P / N area is high, and the edge-grabbing printing method cannot achieve high-precision alignment to complete the printing. Different from the traditional screen camera method of grabbing the Mark point, the conventional process camera and light are placed on the top of the battery cell to illuminate and take pictures to grab the graphics to complete the grab point method. After the coating, the surface of the battery cell has a 2μm thick white tin and a 4μm thick copper layer. The camera has insufficient penetration when taking pictures above the battery cell, which will cause the grab point deviation or direct grab failure. Summary of the invention

[0004] The present invention aims at a method for optimizing TBC battery technology to solve the following problems:

[0005] (1) The screen cost is high, the N / P electrode area and the main grid cannot be printed in one go, the ink sticks to the plate, and the ink sticks to the screen during the mask printing process, resulting in abnormal screen explosion;

[0006] (2) The warpage / bending of the cell after printing, curing and drying is too high, and the drying efficiency is low;

[0007] (3) The camera has insufficient penetration when taking photos above the battery cell, resulting in deviation of the grasping point or direct grasping failure.

[0008] A method for optimizing a TBC battery process comprises the following steps:

[0009] S1, pre-order step;

[0010] S2. Improve the screen by using screen printing technology to perform mask printing on the electroplated cell, reduce the screen parameter specification requirements, widen the grid line width, and provide a layer of anti-stick coating film at the bottom of the screen;

[0011] S3, the drying method is improved, and a curing oven is used to dry the cell after printing the mask. The curing oven uses hot air drying, low temperature and long-term curing and air drying;

[0012] S4, Mark point grasping method is improved, the camera is placed directly above the battery cell, auxiliary lights are added on both sides of the battery cell, and light source is supplemented from the side of the battery cell;

[0013] S5, subsequent steps.

[0014] The S1 pre-sequence steps are polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, and coating.

[0015] The subsequent steps of S5 are post-etching / cleaning, testing and sorting.

[0016] Preferably, the mesh size of the screen is 350-400 meshes.

[0017] Preferably, the gate line width is 250-300 μm.

[0018] Preferably, the mask printing is performed by ink printing.

[0019] Preferably, the drying temperature is 60-80°C.

[0020] Preferably, the drying time in the temperature zone of the curing furnace is 40-60s, and the total drying time is 8min.

[0021] The surface layer of the battery cell includes a tin layer and a copper layer, the tin layer has a thickness of 2 μm, and the copper layer has a thickness of 4 μm.

[0022] A TBC battery, characterized in that the TBC battery is prepared by the preparation method of the TBC battery according to any one of claims 1 to 9.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Improved screen printing, using mask printing, meets the needs of mask printing while reducing screen costs. Compared with the high-specification screens required for conventional silver paste printing, it has more economic advantages; it can complete the printing and forming of the N / P electrode area and the main grid at one time, simplifying the printing process and improving production efficiency; the anti-stick coating film effectively solves the problem of ink adsorption to the battery cell during the printing process, reduces the abnormal situation of sticking to the cell and exploding the plate, makes the ink easy to fall off after printing without sticking to the board, and improves the printing quality and product qualification rate.

[0025] 2. Improved drying method. A curing oven is used to dry the cells after printing the mask, which effectively reduces the warpage of the cells. After drying, the curvature can be reduced to about 1mm, meeting the requirements of automatic direct transmission and loading and unloading. Hot air drying and low-temperature long-term curing and air drying are used to fully volatilize the internal components of the ink, so that the mask ink material is acid-resistant and corrosion-resistant during the etching process. The production capacity is high, and 8-10 flower baskets can be accommodated at a time for simultaneous drying and curing. Each flower basket can hold 100-120pcs of cells. The drying temperature is about 70°, and the drying time of each temperature zone can be freely adjusted. The total time is about 8 minutes. It is flexible and can adjust the curvature by temperature and time.

[0026] 3. Improved the point grabbing method of Mark. The camera is placed directly above the cell and auxiliary lights are added on both sides of the cell. This solves the problem of point grabbing deviation or failure due to insufficient camera penetration caused by the coating on the cell. The height difference between the sunken Mark point and the cell surface can be clearly identified through side lighting, which improves the accuracy of point grabbing. It can achieve the accuracy of point grabbing during printing, meet the high requirements of printing accuracy in the P / N area, thereby ensuring printing quality and helping to improve the process stability and product quality during the BC battery production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 It is a process of a method for optimizing TBC battery process in an embodiment of the present invention;

[0029] Figure 2 is a back structural diagram of a battery in an embodiment of the present invention;

[0030] Figure 31 is a diagram showing the internal structure of a curing furnace in an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following will be combined with the accompanying drawings in the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work belong to the protection scope of the present invention.

[0032] The following is combined with Figure 1 To Attachment Figure 3 And specific embodiments, the present invention is described in detail:

[0033] like Figures 1 to 3 As shown, the object of the present invention is to provide a TBC battery, wherein the TBC battery is prepared by the TBC battery preparation method as described in any one of claims 1-9.

[0034] The purpose of the present invention is achieved through the following technical solutions:

[0035] Embodiment 1:

[0036] Process such as Figure 1 shown.

[0037] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0038] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2 The anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking and bursting the plate, so that the ink can be easily removed after printing without sticking to the plate.

[0039] S3, improve the drying method, use a curing oven to dry the battery after printing the mask (such as Figure 3 As shown). Hot air drying and low temperature long-time curing air drying are adopted to fully volatilize the internal components of the ink, so as to achieve the effect of acid and corrosion resistance of the mask ink material during the etching process. The interior can accommodate 8-10 flower baskets for drying and curing at the same time, and each flower basket can hold 100-120pcs of battery cells. The drying temperature is 70 degrees Celsius, and the drying time in each temperature zone is 40 to 60 seconds, and the total drying time is 8 minutes.

[0040] S4, Mark point grabbing method is improved, the camera is placed just above the battery cell, and auxiliary lights are added on both sides of the battery cell.

[0041] S5, post-etching / cleaning, testing and sorting.

[0042] Embodiment 2:

[0043] Process such as Figure 1 shown.

[0044] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0045] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2 The anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking and bursting the plate, so that the ink can be easily removed after printing without sticking to the plate.

[0046] S3. Improved drying method, using curing oven to dry the cells after printing the mask. Use hot air drying and low temperature long-term curing air drying to fully volatilize the internal components of the ink, so that the mask ink material is acid-resistant and corrosion-resistant during the etching process. The interior can accommodate 8-10 flower baskets for simultaneous drying and curing, and each flower basket can hold 100-120pcs of cells. The drying temperature is 60 degrees Celsius, and the drying time in each temperature zone is 40 to 60 seconds, with a total drying time of 8 minutes.

[0047] S4, Mark point grabbing method is improved, the camera is placed just above the battery cell, and auxiliary lights are added on both sides of the battery cell.

[0048] S5, post-etching / cleaning, testing and sorting.

[0049] Embodiment 3:

[0050] Process such as Figure 1 shown.

[0051] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0052] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2 The anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking and bursting the plate, so that the ink can be easily removed after printing without sticking to the plate.

[0053] S3. Improved drying method, using curing oven to dry the cells after printing the mask. Use hot air drying and low temperature long-term curing air drying to fully volatilize the internal components of the ink, so that the mask ink material is acid-resistant and corrosion-resistant during the etching process. The interior can accommodate 8-10 flower baskets for simultaneous drying and curing, and each flower basket can hold 100-120pcs of cells. The drying temperature is 80 degrees Celsius, and the drying time in each temperature zone is 40 to 60 seconds, with a total time of 8 minutes.

[0054] S4, Mark point grabbing method is improved, the camera is placed just above the battery cell, and auxiliary lights are added on both sides of the battery cell.

[0055] S5, post-etching / cleaning, testing and sorting.

[0056] Comparative Example 1:

[0057] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0058] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2 As shown); an anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking to the sheet and exploding the plate, so that the ink can be easily removed after printing without sticking to the plate;

[0059] S3. Use a conventional oven for drying, the drying time is about 12 seconds, and use lamp heating to dry at high temperature in a short time, the drying temperature is 100℃ to 260℃.

[0060] S4. The method of grabbing the mark point is improved. The camera is placed directly above the battery cell, and auxiliary lights are added on both sides of the battery cell to supplement the light source from the side of the battery cell.

[0061] S5, post-etching / cleaning, testing and sorting.

[0062] Comparative Example 2:

[0063] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0064] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2 As shown); an anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking to the sheet and exploding the plate, so that the ink can be easily removed after printing without sticking to the plate;

[0065] S3. Improve the drying method, and use a curing oven to dry the cell after printing the mask. Use hot air drying and low-temperature long-term curing air drying to fully volatilize the internal components of the ink, so that the mask ink material is acid-resistant and corrosion-resistant during the etching process. The drying temperature is 50℃ or 90℃-120℃, and the drying time in each temperature zone is 40 to 60 seconds, with a total drying time of 8 minutes.

[0066] S4. The method of grabbing the mark point is improved. The camera is placed directly above the battery cell, and auxiliary lights are added on both sides of the battery cell to supplement the light source from the side of the battery cell.

[0067] S5, post-etching / cleaning, testing and sorting.

[0068] Comparing Example 1 with Comparative Example 1 and Comparative Example 2, different drying temperatures in the oven and different drying temperatures in the curing furnace, the following table is obtained:

[0069]

[0070] Table 1

[0071]

[0072]

[0073] Table 2

[0074] It can be seen from the examples, comparative examples and charts that the higher the temperature, the better the curing effect, but the higher the warpage after curing. Conventional ovens generally use high-temperature drying in a short time, and the required temperature is high, but the warpage after curing is high, and the curing rate becomes lower after the temperature is low. The required temperature of the curing furnace is low, the warpage is low, and the curing effect is very good. The curing effect is low and the curing effect is good at 60℃-80℃, and 70℃ is the most preferred.

[0075] Comparative Example 3:

[0076] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0077] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2 As shown); an anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking to the sheet and exploding the plate, so that the ink can be easily removed after printing without sticking to the plate;

[0078] S3. Improve the drying method, and use a curing furnace to dry the cell after printing the mask. Use hot air drying and low-temperature long-term curing air drying to fully volatilize the internal components of the ink, so that the mask ink material is acid-resistant and corrosion-resistant during the etching process. The drying temperature is 70°C, and the drying time in each temperature zone is 40 to 60 seconds, with a total drying time of 8 minutes.

[0079] S4, Mark point adopts edge-grabbing printing.

[0080] Comparative Example 4:

[0081] S1, polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, coating.

[0082] S2, screen improvement, using mask printing, the mesh of the screen is between 350 and 400 meshes, which meets the needs of mask printing and reduces the cost of the screen; widen the grid line, the grid line width is between 250-300μm, and complete the printing and forming of the N / P electrode area and the main grid at one time (such as Figure 2As shown); an anti-stick coating film is added to the bottom of the screen to reduce the abnormal situation of sticking to the sheet and exploding the plate, so that the ink can be easily removed after printing without sticking to the plate;

[0083] S3. Improve the drying method, and use a curing furnace to dry the cell after printing the mask. Use hot air drying and low-temperature long-term curing air drying to fully volatilize the internal components of the ink, so that the mask ink material is acid-resistant and corrosion-resistant during the etching process. The drying temperature is 70°C, and the drying time in each temperature zone is 40 to 60 seconds, with a total drying time of 8 minutes.

[0084] S4, Mark point adopts grab point printing.

[0085] By comparing Example 1 with Comparative Examples 3 and 4, different mark point grabbing methods are statistically obtained as follows:

[0086] Verification Verification quantity (pcs) Printing overprint offset quantity Failure rate of grasping points Edge printing 100 26 26％ dot printing 100 68 68％ Side lights assist in grabbing the print 100 0 0％

[0087] It can be seen from the examples, comparative examples and charts that edge-grabbing printing: when the verification quantity is 100 pcs, the number of printing overprint offsets is 26, and the percentage of point grabbing failures is 26%. The overprint accuracy of edge-grabbing printing is poor. After tin plating, the edge of the battery is prone to slight oxidation and blackening. It is easy to deviate from the angle when grasping the edge, and the overprinting is poor. Point-grabbing printing: with the same verification quantity of 100 pcs, the percentage of point-grabbing failures is as high as 68%, and the number of printing overprint offsets is 68. In traditional point-grabbing printing, the surface of the finished sample after electroplating is white and has a high degree of roughness. The camera cannot directly penetrate the mark, and the grasping rate is low, which can easily misjudge the wrong grasping point. Side light-assisted point-grabbing printing: the verification quantity is also 100 pcs, but the number of printing overprint offsets is 0, and the percentage of point-grabbing failures is 0%. The camera light is moved to both sides of the cell with the aid of a link frame, and the side light is used to assist the side light to assist the point grabbing printing on the cell surface. The finished electroplated sheet is illuminated by the side light to assist the concave rectangular Mark point, which has a significant height difference. The camera algorithm can be re-edited to grab the Mark point, and the concave mark point can be grabbed by irradiating the side light to achieve a higher point grabbing rate. This shows that the side light assisted point grabbing printing method performed well in this verification and can effectively avoid the problems of overprint offset and point grabbing failure.

[0088] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and descriptions are only optional examples of the present invention and are not intended to limit the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for preparing a TBC battery, characterized in that: The following steps are involved: S1, pre-order step; S2. Improve the screen by using screen printing technology to perform mask printing on the electroplated cell, reduce the screen parameter specification requirements, widen the grid line width, and provide a layer of anti-stick coating film at the bottom of the screen; S3, the drying method is improved, and a curing oven is used to dry the cell after printing the mask. The curing oven uses hot air drying, low temperature and long-term curing and air drying; S4, Mark point grasping method is improved, the camera is placed directly above the battery cell, auxiliary lights are added on both sides of the battery cell, and light source is supplemented from the side of the battery cell; S5, subsequent steps.

2. The method for preparing a TBC battery according to claim 1, characterized in that: The S1 pre-sequence steps are polishing and cleaning, tunneling layer B-Poly layer, B-Diff, patterned P area, polishing and cleaning, tunneling layer P-Poly layer, P-Diff, patterned N area, polishing and cleaning, etching, texturing, ALD double-sided aluminum oxide, front / back film, laser local opening, sintering, cleaning, PVD seed layer, and coating.

3. The method for preparing a TBC battery according to claim 1, characterized in that: The subsequent steps of S5 are post-etching / cleaning, testing and sorting.

4. The method for preparing a TBC battery according to claim 1, characterized in that: The mesh number of the screen is 350-400 meshes.

5. The method for preparing a TBC battery according to claim 1, characterized in that: The gate line width is 250-300μm.

6. The method for preparing a TBC battery according to claim 1, characterized in that: The mask printing is performed by ink printing.

7. The method for preparing a TBC battery according to claim 1, characterized in that: The drying temperature is 60-80℃.

8. The method for preparing a TBC battery according to claim 1, characterized in that: The drying time in the temperature zone of the curing furnace is 40-60s, and the total drying time is 8min.

9. The method for preparing a TBC battery according to claim 1, characterized in that: The surface layer of the battery cell includes a tin layer and a copper layer, the tin layer has a thickness of 2 μm, and the copper layer has a thickness of 4 μm.

10. A TBC battery, characterized in that: The TBC battery is prepared by the method for preparing a TBC battery according to any one of claims 1 to 9.

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