High efficiency bc photovoltaic cell with multilayer passivation structure
By introducing a multi-layer passivation structure into BC photovoltaic cells, including an outer AlOx layer and a composite passivation layer, the problem of high light reflectivity in existing technologies is solved, achieving higher light absorption and improved cell performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- JIANGSU RUNERGY CENTURY PHOTOVOLTAIC TECH CO LTD
- Filing Date
- 2025-07-29
- Publication Date
- 2026-06-16
AI Technical Summary
The passivation film of existing BC photovoltaic cells results in a high average reflectivity of light in the wavelength range of 300-1100nm, which leads to the loss of sunlight due to reflection and a reduction in light absorption.
A multi-layer passivation structure is adopted, including an outer AlOx layer, a composite passivation layer and a solar panel. The composite passivation layer is composed of SiOx, SiONx, SiNx and an inner AlOx layer. By optimizing the combination and deposition sequence of the thin film layers, the light reflectivity is reduced and the passivation effect is improved.
It reduces the average reflectivity of light in the 300-1200nm range by 3-5%, improves carrier lifetime and battery performance, reduces light loss, and enhances the conversion efficiency of photovoltaic cells.
Smart Images
Figure CN224368233U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of photovoltaic cell technology, and in particular to a high-efficiency BC photovoltaic cell with a multilayer passivation structure. Background Technology
[0002] With the continuous growth of global demand for clean energy, photovoltaic power generation, as a sustainable energy solution, is experiencing a sustained expansion in market size. Among various photovoltaic cell technologies, BC (Back Contact) cells, due to their unique structural design, exhibit high conversion efficiency potential and have become one of the current research and industrial development hotspots. Existing BC cells typically employ a SiNx / SiOx double-layer anti-reflection passivation film on the front side. SiNx possesses excellent anti-reflection properties, reducing sunlight reflection on the cell surface and increasing light incidentness; SiOx, on the other hand, provides passivation, reducing the recombination rate on the cell surface and improving carrier lifetime. This double-layer structure enhances cell performance to a certain extent.
[0003] However, the passivation films in the existing technology have an average reflectivity of about 5-8% for light in the wavelength range of 300-1100nm, resulting in more sunlight being reflected and lost, and a reduction in light absorption. Utility Model Content
[0004] The purpose of this invention is to provide a high-efficiency BC photovoltaic cell with a multilayer passivation structure to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a high-efficiency BC photovoltaic cell with a multilayer passivation structure, comprising: an outer AlOx layer, a composite passivation layer, and a solar panel, wherein the composite passivation layer is deposited on the front side of the solar panel, and the outer AlOx layer is deposited on the front side of the composite passivation layer.
[0006] Preferably, the composite passivation layer comprises a SiOx layer, wherein the outer AlOx layer is deposited on the front side of the SiOx layer.
[0007] Preferably, the composite passivation layer further includes a SiONx layer, wherein the SiOx layer is deposited on the front side of the SiONx layer.
[0008] Preferably, the composite passivation layer further includes a SiNx layer, wherein the SiONx layer is deposited on the front side of the SiNx layer.
[0009] Preferably, the composite passivation layer further includes an inner AlOx layer, wherein the SiNx layer is deposited on the front side of the inner AlOx layer.
[0010] Preferably, the inner AlOx layer is deposited on the front side of the solar panel.
[0011] Preferably, the back of the solar panel is connected to a PN junction and a metal contact surface.
[0012] Preferably, the thickness of the inner AlOx layer is 4-4.5 nm.
[0013] Preferably, the thickness of the outer AlOx layer is 3.5-4 nm.
[0014] Preferably, the thickness of the solar panel is 130 μm.
[0015] The beneficial effects of this utility model are as follows:
[0016] The combination of the outer AlOx layer and the composite passivation layer reduces the average reflectivity of light in the wavelength range of 300-1200nm by 3-5%. Attached image description:
[0017] Figure 1 This is a schematic cross-sectional view of the main structure of this utility model;
[0018] Figure 2 This is a schematic diagram showing the relative positional relationship between the solar panel and the inner AlOx layer of this utility model.
[0019] In the figure: outer AlOx layer 1, composite passivation layer 2, solar panel 3, SiOx layer 4, SiONx layer 5, SiNx layer 6, inner AlOx layer 7. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0021] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.
[0022] Example 1: Reference Figures 1-2A high-efficiency BC photovoltaic cell with a multilayer passivation structure includes: an outer AlOx layer 1, a composite passivation layer 2, and a solar panel 3. The composite passivation layer 2 is deposited on the front side of the solar panel 3, and the outer AlOx layer 1 is deposited on the front side of the composite passivation layer 2.
[0023] The principles and beneficial effects of the above scheme are as follows:
[0024] The outer AlOx layer 1 and the composite passivation layer 2 are deposited from top to bottom on the front side of the solar panel 3, which faces the sunlight. The solar panel 3 is a silicon wafer. The outer AlOx layer 1 can block the influence of external environmental factors on the internal structure and improve the stability of the composite passivation layer 2. The outer AlOx layer 1 has excellent chemical stability and good passivation performance. It can effectively reduce the dangling bond density on the surface of the cell and reduce carrier recombination. The outer AlOx layer 1 and the composite passivation layer 2 work together to reduce the average reflectivity of light in the wavelength range of 300-1200nm by 3-5%.
[0025] After being placed in an environment of 85℃ and 85% relative humidity for 1000 hours, the performance degradation of the solar panel 3 using this structure is less than 5%.
[0026] Example 2: Reference Figures 1-2 The composite passivation layer 2 includes a SiOx layer 4, and the outer AlOx layer 1 is deposited on the front side of the SiOx layer 4.
[0027] The composite passivation layer 2 further includes a SiONx layer 5, wherein the SiOx layer 4 is deposited on the front side of the SiONx layer 5.
[0028] The composite passivation layer 2 further includes a SiNx layer 6, wherein the SiONx layer 5 is deposited on the front side of the SiNx layer 6.
[0029] The composite passivation layer 2 further includes an inner AlOx layer 7, wherein the SiNx layer 6 is deposited on the front side of the inner AlOx layer 7.
[0030] The inner AlOx layer 7 is deposited on the front side of the solar panel 3.
[0031] The principles and beneficial effects of the above scheme are as follows:
[0032] The composite passivation layer 2 includes a SiOx layer 4, a SiONx layer 5, a SiNx layer 6, and an inner AlOx layer 7. The SiOx layer 4 can play a role in transition and auxiliary passivation. It has good compatibility with the outer AlOx layer 1 and the SiONx layer 5, which can optimize the interface characteristics of the entire structure, reduce defects and recombination centers at the interface, and further improve the passivation effect. At the same time, the SiOx layer 4 has high light transmittance and will not have a negative impact on the optical performance of the solar panel 3.
[0033] The SiONx layer 5 combines some of the characteristics of SiNx and SiO2, and has a good ability to reduce light reflection and passivation performance. In this structure, it further optimizes the incident and reflected light, reduces light loss, and at the same time plays a certain passivation role on the surface of the solar panel 3. It works together with other thin film layers to improve the overall performance of the solar panel 3.
[0034] The SiNx layer 6 near the solar panel 3 mainly plays a role in reducing light reflection, minimizing the reflection of sunlight on the surface of the solar panel, increasing the amount of light absorbed, and providing more usable photons for the solar panel. At the same time, it also has a certain passivation effect, working in synergy with other thin film layers to further improve the performance of the solar panel 3.
[0035] The inner AlOx layer 7 further enhances the passivation of the surface of the solar panel 3 and works synergistically with other thin films to improve carrier lifetime. In addition, the outer AlOx layer 1 and the inner AlOx layer 7, based on their beneficial chemical stability and passivation capabilities, can also effectively reduce the dangling bond density on the surface of the solar panel 3 and reduce carrier recombination.
[0036] Example 3: Reference Figures 1-2 The back of the solar panel 3 is connected to a PN junction and a metal contact surface.
[0037] The principles and beneficial effects of the above scheme are as follows:
[0038] The back of the solar panel 3 is connected to a PN junction and a metal contact surface. The front of the solar panel 3 is deposited from bottom to top with an inner AlOx layer 7, a SiNx layer 6, a SiONx layer 5, a SiOx layer 4 and an outer AlOx layer 1 to form a solar cell panel.
[0039] Example 4: Reference Figures 1-2 The thickness of the inner AlOx layer 7 is 4-4.5 nm.
[0040] The outer AlOx layer 1 has a thickness of 3.5-4 nm.
[0041] The thickness of the solar panel 3 is 130 μm.
[0042] The principles and beneficial effects of the above scheme are as follows:
[0043] The reduction in the thickness of the outer AlOx layer 1, the inner AlOx layer 7, and the solar panel 3 lowers the cost of manufacturing solar panels.
[0044] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.
Claims
1. A high-efficiency BC photovoltaic cell with a multilayer passivation structure, characterized in that, include: The battery has an outer AlOx layer (1), a composite passivation layer (2), and a battery panel (3). The front side of the battery panel (3) is deposited with a composite passivation layer (2), and the front side of the composite passivation layer (2) is deposited with an outer AlOx layer (1).
2. The high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 1, characterized in that, The composite passivation layer (2) includes a SiOx layer (4), and the outer AlOx layer (1) is deposited on the front side of the SiOx layer (4).
3. The high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 2, characterized in that, The composite passivation layer (2) further includes a SiONx layer (5), wherein the SiOx layer (4) is deposited on the front side of the SiONx layer (5).
4. The high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 3, characterized in that, The composite passivation layer (2) further includes a SiNx layer (6), wherein the SiONx layer (5) is deposited on the front side of the SiNx layer (6).
5. A high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 4, characterized in that, The composite passivation layer (2) further includes an inner AlOx layer (7), wherein the SiNx layer (6) is deposited on the front side of the inner AlOx layer (7).
6. A high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 5, characterized in that, The inner AlOx layer (7) is deposited on the front side of the solar panel (3).
7. A high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 6, characterized in that, The back of the solar panel (3) is connected to a PN junction and a metal contact surface.
8. A high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 6, characterized in that, The thickness of the inner AlOx layer (7) is 4-4.5 nm.
9. A high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 2, characterized in that, The outer AlOx layer (1) has a thickness of 3.5-4 nm.
10. A high-efficiency BC photovoltaic cell with a multilayer passivation structure according to claim 7, characterized in that, The thickness of the solar panel (3) is 130 μm.