Battery piece with composite transmission layer insulation structure

Abstract

The utility model provides a battery piece with a composite transmission layer insulation structure, which comprises a battery piece lining body and a covering layer arranged on the peripheral side edge of the battery piece lining body, the covering layer completely covers the peripheral side edge of the battery piece lining body along the thickness direction of the battery piece lining body, and the covering layer covers the peripheral side edge of the battery piece lining body along the direction from the side surface to the outside of the battery piece lining body. An intrinsic layer, a doping layer, a TCO layer and a conducting layer are sequentially arranged on each of the two side faces of the cell lining body. The solar cell has the advantages that the covering layer covers the peripheral side edge of the cell lining body, deposition covering cannot be conducted on the peripheral side face of the cell lining body in the film deposition process, the winding plating phenomenon is avoided, the range of an insulation area is reduced, the electricity receiving area is not sacrificed, the double-sided rate is not lost, and the short circuit risk of the cell is isolated.

Description

Technical Field

[0001] The utility model belongs to the technical field of solar cell production, and in particular relates to a solar cell with a composite transmission layer insulation structure. Background Art

[0002] At present, the industry is continuously improving the power generation efficiency of solar modules in two major industrial links. First, in the production of solar cells, the copper electroplating process is introduced, combined with the yellow light patterning process, so that the overall fine grid line width is less than 20um or even finer. In this way, the shading rate and contact resistance can be reduced, so that the overall solar cell conversion efficiency is increased by an average of 0.3% to 0.5%.

[0003] However, before the electroplating process is carried out, a bottom conductive layer must be introduced as an electroplating seed layer. The generally mature and stable process is to prepare a vacuum deposition layer for the physical vapor deposition process (PVD). Although it is very mature and stable, its process characteristics are that it not only covers the front and back sides of the cell, but also deposits and covers the sides, forming the so-called wrap-around plating phenomenon. In the subsequent electroplating deposition process, the side leakage of the cell causes the opening voltage Voc of the cell to decrease, and ultimately reduces the photoelectric conversion efficiency of the cell. The current solution is to shrink the back edge of the cell toward the center to form a physical isolation space. This will inevitably cause losses to the power collection and bifaciality of the cell. Utility Model Content

[0004] In view of the above problems, the utility model provides a battery cell with a composite transmission layer insulation structure to solve the above or other former problems existing in the prior art.

[0005] In order to solve the above technical problems, the technical solution adopted by the utility model is: a battery cell with a composite transmission layer insulation structure, including a battery cell liner and a covering layer arranged on the peripheral side of the battery cell liner. Along the thickness direction of the battery cell liner, the covering layer completely covers the peripheral side of the battery cell liner, and along the side of the battery cell liner to the outside, the two sides of the battery cell liner are sequentially provided with an intrinsic layer, a doping layer, a TCO layer and a conductive layer.

[0006] Furthermore, the covering layer is a peelable adhesive, which is cured by UV light after coating, and the thickness of the covering layer along the thickness direction perpendicular to the battery cell liner is 10-50um.

[0007] Furthermore, the UV lamp irradiation time is 20-120s, and the light intensity of the UV lamp is 300-3000mj / cm2.

[0008] Furthermore, the doping layers arranged on both sides of the cell substrate are respectively a microcrystalline P doping layer and a microcrystalline N doping layer, the thickness of the microcrystalline P doping layer is 1-30nm, and the thickness of the microcrystalline N doping layer is 1-30nm.

[0009] Furthermore, the thickness of the intrinsic layer is 1-10 nm, the thickness of the TCO layer is 30 nm-150 nm, and the thickness of the conductive layer is 30 nm-150 nm.

[0010] Furthermore, on one side of the cell substrate, an electron transport layer and a hole transport layer are disposed between the TCO layer and the conductive layer, and the electron transport layer and the hole transport layer are disposed in sequence along the direction from the conductive layer to the TCO layer.

[0011] Due to the adoption of the above technical scheme, after the velvet surface is prepared on the battery cell liner, a covering layer is prepared on the peripheral side of the battery cell liner. Along the thickness direction of the battery cell liner, the covering layer completely covers the peripheral side of the battery cell liner. Then, the deposition of the photoelectric conversion layer structure and the deposition of the composite transmission layer structure are carried out. In the process of depositing the thin film, the peripheral side of the battery cell liner will not be deposited and covered, thereby avoiding the formation of wrap-around plating, reducing the scope of the insulating area, not sacrificing the power collection area and losing the double-sidedness, and isolating the risk of battery short circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a schematic structural diagram of a battery cell liner after a covering layer is prepared according to an embodiment of the utility model;

[0013] Figure 2 It is a schematic diagram of the structure of a cell after the intrinsic layer, the doping layer, the TCO layer and the bottom conductive layer are deposited after the cover layer is solidified in one embodiment of the utility model;

[0014] Figure 3 This is a schematic structural diagram of a battery cell after removing the covering layer in one embodiment of the utility model;

[0015] Figure 4 This is another structural schematic diagram of a battery cell after removing the covering layer according to an embodiment of the utility model.

[0016] In the figure:

[0017] 1. Cell substrate 2. Covering layer 3. Intrinsic layer

[0018] 4. Doping layer 5. TCO layer 6. Conductive layer

[0019] 7. Hole transport layer 8. Electron transport layer DETAILED DESCRIPTION

[0020] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments.

[0021] Figure 1 A structural schematic diagram of an embodiment of the utility model is shown. This embodiment relates to a battery cell with a composite transmission layer insulation structure and a preparation method. After the velvet surface is prepared on the battery cell liner, a covering layer is coated on the peripheral side of the battery cell liner, and then thin film structures such as an intrinsic layer, a doping layer, a TCO layer and a conductive layer are prepared to reduce the range of the insulation area without sacrificing the power collection area and losing the double-sidedness, and at the same time, the risk of battery short circuit is isolated.

[0022] A battery cell with a composite transmission layer insulation structure, such as Figure 2 As shown, it includes a battery cell liner 1 and a covering layer 2 arranged on the peripheral side of the battery cell liner 1. Along the thickness direction of the battery cell liner 1, the covering layer 2 completely covers the peripheral side of the battery cell liner 1. The covering layer 2 wraps the peripheral side of the battery cell liner 1 to prevent the deposition layer from covering the peripheral side of the battery cell liner 1 during electroplating deposition, thereby avoiding the formation of the bypass plating phenomenon. The covering layer 2 is arranged along the circumferential side of the cell substrate 1, and wraps all the circumferential side of the cell substrate 1. Specifically, the covering layer 2 includes a plurality of long strip structures with a certain length connected end to end in sequence, and covers each side of the cell substrate 1 respectively. The number of the long strip structures is consistent with the number of the sides of the cell substrate 1, and each long strip structure covers one side of the cell substrate 1. For example, if the cell substrate 1 has four sides, then the number of the long strip structures is four, and the four long strip structures cover the four sides of the cell substrate 1 respectively; the adjacent long strip structures are fixedly connected, and the fixed connection method is preferably integrally formed. The cross-sectional shape of the long strip structure can be square, circular, or other shapes, which can be selected according to actual needs. Along the thickness direction of the cell substrate (along the axial direction of the cell substrate), the length of the long strip structure is greater than the thickness of the cell substrate 1, that is, the covering layer 2 protrudes from both sides of the cell substrate 1 to achieve full coverage of the circumferential side of the cell substrate 1. The covering layer 2 is prepared by using an edge wrapping process, and the material for forming the covering layer 2 is sequentially and continuously coated along the peripheral side of the cell substrate 1, and the covering layer 2 is formed after curing. The length dimension of the covering layer 2 along the thickness direction of the cell substrate is selected according to the thickness of the cell substrate 1, and no specific requirements are made here.

[0023] Both sides of the cell substrate 1 are sequentially provided with an intrinsic layer 3, a doping layer 4, a TCO layer 5 and a conductive layer 6 along the side of the cell substrate 1 to the outside, that is, on one side of the cell substrate 1, from the side of the cell substrate 1 to the outside, the intrinsic layer 3, the doping layer 4, the TCO layer 5 and the conductive layer 6 are sequentially provided, and on the other side of the cell substrate 1, from the side of the cell substrate 1 to the outside, the intrinsic layer 3, the doping layer 4, the TCO layer 5 and the conductive layer 6 are sequentially provided to form a cell structure. The intrinsic layer 3 and the doping layer 4 constitute a photoelectric conversion layer for photoelectric conversion, and the TCO layer and the conductive layer 6 constitute a composite transmission layer for carrier transmission.

[0024] In some feasible embodiments, the side of the cell substrate 1 is located in the middle area of ​​the cover layer 2. At the same time, the cover layer 2 is arranged along the thickness direction of the cell substrate 1. The cover layer 2 protrudes from the two sides of the cell substrate 1 at the same height, so that the cover layer 2 does not cover the two sides of the cell substrate 1, so as to deposit various thin film structures on the two sides of the cell substrate 1. The cover layer 2 is a temporary cover layer 2. After the intrinsic layer 3, the doping layer 4, the TCO layer 5 and the conductive layer 6 are deposited, the cover layer 2 is removed to obtain a cell with a composite transmission layer insulation structure.

[0025] Therefore, the material of the above-mentioned covering layer 2 is peelable adhesive, and the edge wrapping process is adopted to successively and sequentially coat the peelable adhesive on the circumferential side edge of the battery cell liner 1 along the circumferential direction of the battery cell liner 1. After coating, the peelable adhesive is cured by UV light and fixed on the circumferential side edge of the battery cell liner 1 to cover the circumferential side edge of the battery cell liner 1 to form a covering layer 2, thereby reducing the range of the insulating area without sacrificing the power receiving area and losing the double-sidedness.

[0026] The peelable adhesive is a commercially available product, which can be selected according to actual needs, and no specific requirements are made here. The peelable adhesive is temperature-resistant and can withstand a temperature of 500°C, and still remain in a solidified state without melting. The deposition process of the intrinsic layer 3 and the doping layer 4 is a plasma enhanced chemical deposition process, and the deposition process of the TCO layer 5 and the conductive layer 6 is a physical vapor deposition process. The temperature range of these two deposition processes is 200°C-350°C. Therefore, the peelable adhesive is used to cover the peripheral side of the battery cell liner 1. It will not melt during the subsequent deposition process of the intrinsic layer 3, the doping layer 4, the TCO layer 5 and the conductive layer 6, and can effectively cover the peripheral side of the battery cell liner 1, reduce the scope of the insulation area, and do not sacrifice the power collection area or lose the double-sidedness.

[0027] The UV lamp is a commercially available product, which is selected according to actual needs, and no specific requirements are made here. When the UV lamp irradiates the coated peelable adhesive, the UV lamp irradiation time is 20-120s, and the irradiation time is selected according to actual needs, and no specific requirements are made here.

[0028] The light intensity of the UV lamp is 300-3000mj / cm 2 The intensity of the UV light is selected according to actual needs, and no specific requirements are made here.

[0029] The thickness of the above-mentioned covering layer 2 along the thickness direction perpendicular to the battery cell liner is 10-50um. The thickness of the covering layer 2 along the thickness direction perpendicular to the battery cell liner is selected according to actual needs and no specific requirements are made here.

[0030] The above-mentioned doping layer 4 includes a microcrystalline P doping layer and a microcrystalline N doping layer, which are deposited by a plasma enhanced chemical deposition process. The microcrystalline P doping layer is deposited on one side of the cell substrate 1, and the microcrystalline N doping layer is deposited on the other side of the cell substrate 1 to form a PN junction and a back surface field respectively.

[0031] The thickness of the above-mentioned microcrystalline P-doped layer is 1-30 nm, and the thickness is selected according to actual needs, and no specific requirements are made here.

[0032] The thickness of the above-mentioned microcrystalline N-doped layer is 1-30 nm, and the thickness is selected according to actual needs, and no specific requirements are made here.

[0033] The thickness of the intrinsic layer 3 is 1-10 nm, and the thickness is selected according to actual needs, and no specific requirements are made here.

[0034] The TCO layer 5 is disposed on the doping layer 4 . The thickness of the TCO layer 5 is 30 nm to 150 nm. The thickness is selected according to actual needs and no specific requirements are made here.

[0035] The thickness of the conductive layer 6 is 30 nm to 150 nm, and the thickness is selected according to actual needs, and no specific requirements are made here.

[0036] A further optimized solution is that on one side of the cell substrate 1, an electron transport layer 8 and a hole transport layer 7 are arranged between the TCO layer 5 and the conductive layer 6, and the electron transport layer 8 and the hole transport layer 7 are arranged in sequence along the direction from the conductive layer 6 to the TCO layer 5. Under this structure, after removing the covering layer 2, a cell with a stacked structure, such as a perovskite cell, is obtained.

[0037] The intrinsic layer 3, doping layer 4, TCO layer 5, conductive layer 6, electron transport layer 8 and hole transport layer 7 mentioned above are all conventional thin film structures in the art, and their materials can be selected according to actual needs.

[0038] The conductive layer 6 mentioned above is the electrode layer, which is a metal electrode arranged on the front and back sides of the battery cell substrate 1 .

[0039] A method for preparing a battery cell having a composite transmission layer insulation structure comprises the following steps:

[0040] like Figure 1 As shown, a covering layer 2 is prepared on the circumferential side of the cell substrate 1. In this step, a peelable adhesive is sequentially coated along the circumferential side of the cell substrate 1 and cured to form a covering layer 2, which covers the circumferential side of the cell substrate 1. Specifically, when the peelable adhesive is coated, the edge wrapping process is adopted so that the covering layer 2 is arranged on the peripheral side of the battery cell liner 1 to cover the peripheral side of the battery cell. After the peelable adhesive is coated, the peelable adhesive is cured so that the colloid hardens and the surface does not stick. When the peelable adhesive is cured, the peelable adhesive is irradiated with a UV lamp for 20-120s. The irradiation time can be 20s, 30s, 40s, 50s, 60s, 70s, 80s, 90s, 100s, 110s, 120s and any time value between 20-120s. The irradiation time is selected according to actual needs and no specific requirements are made here. The light intensity of the UV lamp is 300-3000mj / cm 2 The light intensity of the UV lamp can be 300mj / cm 2 、800mj / cm 2 、1300mj / cm 2 、1800mj / cm 2 、2300mj / cm 2 、2800mj / cm 2 and between 300-3000mj / cm 2 Any light intensity value can be selected according to actual needs, and no specific requirements are made here.

[0041] The length of the cover layer 2 along the thickness direction of the cell substrate is greater than the thickness of the cell substrate, so as to facilitate the subsequent deposition of thin film structures such as the intrinsic layer 3 , the doping layer 4 , the TCO layer 5 and the conductive layer 6 .

[0042] The thickness of the above-mentioned covering layer 2 along the thickness direction perpendicular to the battery cell liner is 10-50um. The thickness of the covering layer 2 can be 10um, 20um, 30um, 40um, 50um and any thickness value between 10-50um. The thickness of the covering layer 2 is selected according to actual needs and no specific requirements are made here.

[0043] The above-mentioned peelable adhesive is a commercially available product and can be selected according to actual needs.

[0044] like Figure 2As shown, after the covering layer 2 is solidified, the intrinsic layer 3 and the doping layer 4 are prepared by a deposition process. In this step, a plasma enhanced chemical deposition process is used to deposit the intrinsic layer 3 and the doping layer 4. The cell substrate 1 after the covering layer 2 is solidified is placed in a deposition device and sequentially enters different vacuum chambers. Different process gases are introduced into different vacuum chambers to sequentially prepare the intrinsic layer 3 and the doping layer 4. The process gases include but are not limited to silane, hydrogen, phosphine and borane, which are selected according to the preparation process of the intrinsic layer 3 and the doping layer 4. The deposition process of the intrinsic layer 3 and the deposition process of the doping layer 4 are conventional technologies in the field and are not described in detail here.

[0045] The above-mentioned doping layer 4 includes a microcrystalline P doping layer and a microcrystalline N doping layer, which are respectively located on the intrinsic layer 3 on both sides of the cell substrate 1. Generally, the microcrystalline P doping layer is located on the intrinsic layer 3 on the back side of the cell substrate 1, and the microcrystalline N doping layer is located on the intrinsic layer 3 on the front side of the cell substrate 1. The thickness of the microcrystalline P doping layer is 1-30nm, and the thickness of the microcrystalline P doping layer is selected according to actual needs, and no specific requirements are made here; the thickness of the microcrystalline N doping layer is 1-30nm, and the thickness of the microcrystalline N doping layer is selected according to actual needs, and no specific requirements are made here.

[0046] The thickness of the intrinsic layer 3 is 1-10 nm. The thickness of the intrinsic layer 3 is selected according to actual needs and no specific requirements are given here.

[0047] After the intrinsic layer 3 and the doping layer 4 are prepared, the TCO layer 5 and the conductive layer 6 are prepared by a physical vapor deposition process. The cell substrate 1 on which the intrinsic layer 3 and the doping layer 4 are prepared is placed in a physical vapor deposition device. According to the material of the thin film structure to be deposited, the corresponding material source is selected to deposit the TCO layer 5 and the conductive layer 6. The deposition process of the TCO layer 5 and the deposition process of the conductive layer 6 are conventional technologies in the field and are not described in detail here.

[0048] Alternatively, after the intrinsic layer 3 and the doping layer 4 are prepared, a TCO layer 5 and a conductive layer 6 are sequentially prepared on the outside of the doping layer 4 on one side of the cell substrate 1 by a physical vapor deposition process, and a TCO layer 5, a hole transport layer 7, an electron transport layer 8 and a conductive layer 6 are sequentially prepared on the outside of the doping layer 4 on the other side of the cell substrate 1. The deposition process of the TCO layer 5, the hole transport layer 7, the electron transport layer 8 and the conductive layer 6 is a conventional technology in the art and will not be described in detail here.

[0049] The thickness of the TCO layer 5 is 30 nm-150 nm. The thickness of the TCO layer 5 is selected according to actual needs and no specific requirements are given here.

[0050] The thickness of the conductive layer 6 is 30 nm to 150 nm. The thickness of the conductive layer 6 is selected according to actual needs and no specific requirements are made here.

[0051] The thickness of the hole transport layer 7 is 5-100 nm. The thickness of the hole transport layer 7 is selected according to actual needs and no specific requirements are made here.

[0052] The thickness of the electron transport layer 8 is 5-100 nm. The thickness of the electron transport layer 8 is selected according to actual needs and no specific requirements are made here.

[0053] like Figure 3 and 4 As shown, after the TCO layer 5 and the conductive layer 6 or the TCO layer 5, the hole transport layer 7, the electron transport layer 8 and the conductive layer 6 are prepared, the covering layer 2 is removed. In this step, the covering layer 2 is cleaned and removed to obtain a battery cell. The covering layer 2 is cleaned and removed by pure water. The covering layer 2 is cleaned by immersion or pressurization. The temperature of the pure water is 70-100°C. The temperature of the pure water is selected according to the time requirement. No specific requirements are made here. The cleaning time is 60-600s. The cleaning time is selected according to actual needs. No specific requirements are made here. When the pressurization method is used, the spraying pressure is 1-5Kg / cm 2 The spraying pressure is selected according to actual needs, and no specific requirements are made here. After the cover layer 2 is cleaned and removed, the battery cell is blown dry to complete the preparation of the battery cell.

[0054] A cell comprises a cell substrate 1, a photoelectric conversion layer structure arranged on both sides of the cell substrate 1, and a composite transmission layer structure arranged on the photoelectric conversion structure, that is, on both side surfaces of the cell substrate 1, the photoelectric conversion layer structure and the composite transmission layer structure are arranged in sequence along the side to the outside, the photoelectric conversion layer structure comprises an intrinsic layer 3 and a doping layer 4, the intrinsic layer 3 and the doping layer 4 are arranged in sequence along the side to the outside of the cell substrate 1, and the composite transmission layer structure comprises a TCO layer 5 and a conductive layer 6, the TCO layer 5 and the conductive layer 6 are arranged in sequence along the doping layer 4 to the outside.

[0055] Alternatively, the composite transport layer structures arranged on the two sides of the cell substrate 1 are different. On one side of the cell substrate 1, the composite transport layer structure includes a TCO layer 5 and a conductive layer 6. The TCO layer 5 and the conductive layer 6 are arranged in sequence from the doping layer 4 to the outside. On the other side of the cell substrate 1, the composite transport layer structure includes a TCO layer 5, a hole transport layer 7, an electron transport layer 8 and a conductive layer 6. Along the doping layer 4 to the outside, the TCO layer 5, the hole transport layer 7, the electron transport layer 8 and the conductive layer 6 are arranged in sequence.

[0056] Due to the adoption of the above technical scheme, after the velvet surface is prepared on the battery cell liner, a covering layer is prepared on the peripheral side of the battery cell liner. Along the thickness direction of the battery cell liner, the covering layer completely covers the peripheral side of the battery cell liner. Then, the deposition of the photoelectric conversion layer structure and the deposition of the composite transmission layer structure are carried out. In the process of depositing the thin film, the peripheral side of the battery cell liner will not be deposited and covered, thereby avoiding the formation of wrap-around plating, reducing the scope of the insulating area, not sacrificing the power collection area and losing the double-sidedness, and isolating the risk of battery short circuit.

[0057] The above is a detailed description of the embodiments of the utility model, but the contents are only preferred embodiments of the utility model and cannot be considered to limit the scope of implementation of the utility model. All equivalent changes and improvements made within the scope of application of the utility model should still fall within the scope of the patent coverage of the utility model.

Claims

1. A battery cell with a composite transmission layer insulation structure, characterized in that: It includes a battery cell liner and a covering layer arranged on the peripheral sides of the battery cell liner. Along the thickness direction of the battery cell liner, the covering layer completely covers the peripheral sides of the battery cell liner. Along the side of the battery cell liner to the outside, both sides of the battery cell liner are sequentially provided with an intrinsic layer, a doping layer, a TCO layer and a conductive layer.

2. The battery cell with a composite transmission layer insulation structure according to claim 1, characterized in that: The covering layer is a peelable adhesive, which is cured by UV light after coating. The thickness of the covering layer along the thickness direction perpendicular to the battery cell liner is 10-50um.

3. The battery cell with a composite transmission layer insulation structure according to claim 2, characterized in that: The UV lamp irradiation time is 20-120s, and the light intensity of the UV lamp is 300-3000mj / cm 2 .

4. The battery cell with a composite transmission layer insulation structure according to any one of claims 1 to 3, characterized in that: The doping layers arranged on both sides of the cell substrate are respectively a microcrystalline P doping layer and a microcrystalline N doping layer, the thickness of the microcrystalline P doping layer is 1-30nm, and the thickness of the microcrystalline N doping layer is 1-30nm.

5. The battery cell with a composite transmission layer insulation structure according to claim 4, characterized in that: The thickness of the intrinsic layer is 1-10 nm, the thickness of the TCO layer is 30 nm-150 nm, and the thickness of the conductive layer is 30 nm-150 nm.

6. The battery cell with a composite transmission layer insulation structure according to any one of claims 1 to 3 and 5, characterized in that: On one side of the cell substrate, an electron transport layer and a hole transport layer are disposed between the TCO layer and the conductive layer, and the electron transport layer and the hole transport layer are disposed in sequence along a direction from the conductive layer to the TCO layer.

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