CN120676719A

CN120676719A - Photovoltaic module and photovoltaic system

Info

Publication number: CN120676719A
Application number: CN202511164720.6A
Authority: CN
Inventors: 张京; 李盼盼; 杨冬生; 胡国波; 陈军
Original assignee: Ordos Longji Photovoltaic Technology Co ltd
Current assignee: Ordos Longji Photovoltaic Technology Co ltd
Priority date: 2025-08-20
Filing date: 2025-08-20
Publication date: 2025-09-19

Abstract

The application discloses a photovoltaic module and a photovoltaic system, wherein the photovoltaic module comprises a plurality of battery pieces and interconnection pieces, the battery pieces are distributed along a first direction, the interconnection pieces are arranged on the battery pieces and are electrically connected with adjacent battery pieces, a plurality of conductive connecting layers distributed at intervals are arranged between one interconnection piece and each battery piece, the interconnection pieces are electrically connected with the battery pieces through the conductive connecting layers, and gaps are formed between at least part of the positions between the interconnection pieces and the battery pieces at positions between the two adjacent conductive connecting layers. In this way, stray light can irradiate into the gap and undergo multiple reflections of the cell surface and the interconnect surface to generate resonance enhancement so as to be absorbed and utilized by the cell, thereby being capable of increasing the light absorptivity of the cell. In addition, the photovoltaic module structure can be realized by optimizing the local structure in the photovoltaic module based on the existing process without introducing new equipment and new materials, and the product cost is not increased.

Description

Photovoltaic module and photovoltaic system

Technical Field

The application belongs to the technical field of photovoltaics, and particularly relates to a photovoltaic module and a photovoltaic system.

Background

The photovoltaic module is a core component of a photovoltaic power generation system, the photovoltaic module converts solar energy into electric energy through a photovoltaic effect, and in the power generation process of the photovoltaic module, only part of sunlight is absorbed and converted by the battery pieces in the module, and the other part of sunlight can pass through gaps of the battery pieces or other forms to be scattered and reflected so as not to be effectively utilized.

In the related art, the light-reflecting adhesive strips are arranged at the positions corresponding to the gaps of the battery pieces in the assembly so as to guide the light transmitted through the gaps to reflect to the battery pieces, and further enhance the light management efficiency. But the arrangement of the reflective adhesive strip not only increases the manufacturing cost, but also causes the problem of hidden cracking of the battery piece in the assembly, and influences the yield of the assembly.

Disclosure of Invention

The application aims to provide a photovoltaic module which can solve the problems that the manufacturing cost is increased and the hidden cracking of a battery piece is easy to occur due to the fact that the light management efficiency is enhanced by arranging a light reflecting strip in the related technology.

In order to solve the technical problems, the application is realized as follows:

In a first aspect, an embodiment of the present application provides a photovoltaic module, including a plurality of battery pieces and an interconnection member;

The plurality of battery pieces are arranged along a first direction, the interconnecting piece is arranged on the battery pieces and is electrically connected with the adjacent battery pieces,

A plurality of conductive connecting layers which are arranged at intervals are arranged between one interconnecting piece and the battery piece, the interconnecting piece is electrically connected with the battery piece through the conductive connecting layers, and gaps are arranged at least at part of positions between the interconnecting piece and the battery piece at positions between two adjacent conductive connecting layers.

Optionally, the height of the gap is less than or equal to 100 μm and greater than or equal to 0 μm in the thickness direction of the battery sheet;

or, the height of the gap is in the range of 0.36 μm to 89.3. Mu.m.

Optionally, the height L of the gap satisfies the following formula:

Wherein n is the refractive index of the medium in the gap, m is a positive integer, lambda ₁ is the wavelength of light which enters the gap and can be used by the battery piece, and delta lambda is the minimum interval between adjacent resonance modes.

Optionally, along the extending direction of the interconnection piece, at least a first position and a second position are located in the gap, and the height of the gap at the first position is larger than the height at the second position;

and/or the gap has a height difference between 0.1 μm and 88 μm at the first position and at the second position;

And/or there are height differences at least 3 positions within one of said gaps.

Optionally, a plurality of conductive connection layers are arranged between the interconnection piece and the battery piece at intervals along the extending direction of the interconnection piece, the gaps are arranged between two adjacent conductive connection layers, and at least two gaps are arranged below one interconnection piece;

and/or, between the adjacent conductive connection layers, the interconnection part is in partial contact with the battery piece.

Optionally, an insulating layer is further disposed between the interconnection piece and the battery piece, the interconnection piece, the conductive connection layer and the insulating layer form the gap.

Optionally, the insulating layer fills at least part of the gap between the interconnect and the battery piece, or the insulating layer is disposed on a side surface of the interconnect.

Optionally, a side surface of the interconnection element facing the gap is in a concave-convex structure;

And/or, the surface of the battery piece facing the gap is in a concave-convex structure.

Alternatively, a height difference between the highest point and the lowest point in the rugged structure is 0.05 μm to 10 μm in the thickness direction of the battery sheet.

Optionally, a side surface of the interconnect facing the gap has protruding tin particles;

and/or, a surface of one side of the battery piece facing the gap is provided with a suede structure.

Optionally, a side surface of the conductive connection layer facing the gap is in a concave-convex structure.

Optionally, the photovoltaic module includes at least one of the following conditions:

A. a plurality of gaps which are distributed at intervals are formed between the same interconnecting piece and the battery piece along the extending direction of the interconnecting piece, and the heights of at least two gaps are unequal;

B. The battery piece is provided with a plurality of interconnecting pieces, the interconnecting pieces comprise a first interconnecting piece and a second interconnecting piece, one gap formed by the first interconnecting piece and the battery piece is a first gap, one gap formed by the second interconnecting piece and the battery piece is a second gap, and the heights of the first gap and the second gap are unequal;

C. The plurality of battery pieces comprise a first battery piece and a second battery piece, one gap formed on the first battery piece is a third gap, one gap formed on the second battery piece is a fourth gap, and the heights of the third gap and the fourth gap are unequal.

Optionally, the photovoltaic module further comprises an encapsulation adhesive layer, wherein at least part of the gap is filled with the encapsulation adhesive layer;

and/or the packaging adhesive layer is arranged between the side surface of the interconnection piece and the battery piece.

Optionally, the refractive index of the packaging adhesive layer is 1.4-1.5;

and/or the height of the encapsulation adhesive layer in the gap is 0.5-100 μm.

Optionally, the conductive connection layer has a first inclined plane along at least one side of the first direction;

And/or, the conductive connection layer is provided with a second inclined plane along at least one side of a second direction, and the second direction is intersected with the first direction.

Optionally, a first included angle is formed between the first inclined plane and the surface of the battery piece, a second included angle is formed between the second inclined plane and the surface of the battery piece, and the first included angle is unequal to the second included angle;

and/or, the surface roughness of the first inclined surface is greater than or equal to 20nm;

And/or, the surface roughness of the second inclined surface is greater than or equal to 20nm.

Optionally, an electrode is disposed on the battery piece at a position corresponding to the gap, and the electrode protrudes from the surface of the battery piece.

Optionally, the height of the electrode protruding from the surface of the battery piece is 2-35 mu m.

Optionally, the interconnection is a flat solder strip;

And/or the width of the interconnection is greater than the thickness of the interconnection;

And/or the width of the interconnection piece is 0.2mm-1mm, and the thickness of the interconnection piece is 0.1 mm-0.5 mm.

Optionally, an electrode is arranged on the back surface of the battery piece, or electrodes are arranged on the front surface and the back surface of the battery piece, and the interconnection piece is electrically connected with the electrode through the conductive connecting layer;

And/or the photovoltaic module is a double-sided glass photovoltaic module.

In a second aspect, an embodiment of the present application provides a photovoltaic system, including a plurality of electrically connected photovoltaic modules, where the photovoltaic modules adopt the photovoltaic modules in the first aspect.

In the embodiment of the application, the interconnection piece is arranged on the surface of the battery piece so as to realize the electrical connection of the adjacent battery pieces by utilizing the interconnection piece, so that the battery pieces are connected to form a string, the conductive connection layer is arranged between the interconnection piece and the battery pieces, the interconnection piece is electrically connected with the battery pieces through the conductive connection layer, and at least part of the area between the interconnection piece and the battery pieces is provided with a gap. Therefore, an optical cavity effect can be formed at the gap, so that stray light can irradiate into the gap and is reflected for multiple times by the surface of the battery piece and the surface of the interconnection piece, resonance enhancement is generated, and the stray light is absorbed and utilized by the battery piece, so that the light absorptivity of the battery piece can be increased, and the efficiency of the photovoltaic module is improved. In addition, the photovoltaic module structure can be realized by optimizing the local structure in the photovoltaic module based on the existing process without introducing new equipment and new materials, and the product cost is not increased.

The foregoing description is only an overview of the present application, and is intended to be implemented in accordance with the teachings of the present application in order that the same may be more clearly understood and to make the same and other objects, features and advantages of the present application more readily apparent.

Drawings

For a clearer description of embodiments of the application or of solutions in the prior art, the drawings that are used in the description of the embodiments will be briefly described, in which:

FIG. 1 is a schematic illustration of the effects of a cavity formed in a photovoltaic module according to an embodiment of the present application;

fig. 2 is a schematic view illustrating a connection structure of an interconnect and a battery cell according to an embodiment of the present application;

FIG. 3 is one of the side cross-sectional views of a photovoltaic module at a conductive connection layer according to an embodiment of the present application;

FIG. 4 is a second side cross-sectional view of a photovoltaic module at a conductive connection layer according to an embodiment of the present application;

fig. 5 is a schematic view showing a connection structure of an interconnect with a battery cell along an extending direction thereof according to an embodiment of the present application;

FIG. 6 is a cross-sectional view of one configuration of an interconnect according to an embodiment of the present application;

FIG. 7 is one of the cross-sectional views of a photovoltaic module at the junction of an interconnect and a cell according to an embodiment of the present application;

FIG. 8 is a second cross-sectional view of a photovoltaic module at the junction of an interconnect and a cell according to an embodiment of the present application;

fig. 9 is a graph of resonant wavelength distribution of a photovoltaic module according to an embodiment of the present application for different gap heights.

Reference numerals:

10, a battery piece; 10a is a first battery piece, 10b is a second battery piece, 11 is a gap, a is a first position, b is a second position, L is the height of the gap, 20 is an interconnection piece, 20a is a first interconnection piece, 20b is a second interconnection piece, 201 is a concave-convex structure, 30 is a conductive connecting layer, 301 is a first inclined plane, 302 is a second inclined plane, A1 is a first included angle, A2 is a second included angle, 40 is an encapsulation glue layer, 50 is an electrode, X is a first direction, Y is a second direction and Z is a third direction.

Detailed Description

Reference will now be made in detail to embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements throughout or elements having like or similar functionality. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The features of the application "first", "second" and the like in the description and in the claims may be used for the explicit or implicit inclusion of one or more such features. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more. Furthermore, in the description and claims, "and/or" means at least one of the connected objects, and the character "/", generally means that the associated object is an "or" relationship.

In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present application and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

In the description of the present application, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present application will be understood in specific cases by those of ordinary skill in the art.

Before introducing the photovoltaic module provided by the embodiment of the application, an application scene of the photovoltaic module is described:

In a photovoltaic power generation system, the actual power generation of a photovoltaic module is affected by various types of light, namely, on one hand, a large amount of sunlight irradiates the front surface of the photovoltaic module, on the other hand, the sunlight irradiates the back surface of a photovoltaic module product through ground reflection, and in addition, part of front light rays can pass through the module through gaps on the front surface of the photovoltaic module due to the existence of the sheet spacing and the string spacing and cannot be directly absorbed by the module. Generally, light which is not directly irradiated on the front surface or the back surface of the photovoltaic module is uniformly defined as module stray light, and the efficient utilization of the stray light passing through and existing in the module is critical for improving the power of the photovoltaic module.

In the related art, for the utilization of gap light, a reflective adhesive strip is added at a position corresponding to a gap in a photovoltaic module, so that light transmitted through the gap is guided to be reflected to a cell, and therefore the light management efficiency is enhanced, and the module power is improved. However, the introduction of the reflective adhesive strip can lead to hidden cracking risk in the process of large-area lifting components, affect the yield of products, and meanwhile, new processing equipment is required to be introduced, so that the cost of the components is increased.

For effective use of ground reflected light, shielding of the back of the component is mainly reduced, such as reducing the width of solder strips and grid lines. However, these measures are required to balance the electrical transmission performance and the optical exposure area, and the actual effect is not ideal.

Therefore, the embodiment of the application provides a photovoltaic module to solve the technical problems existing in the prior art, and the photovoltaic module provided by the embodiment of the application is described in detail through specific embodiments and application scenes thereof by combining with the attached drawings.

As shown in fig. 1 and 2, and fig. 7 and 8, a photovoltaic module according to some embodiments of the present application includes a plurality of battery cells 10 and an interconnection member 20, wherein the plurality of battery cells 10 are arranged along a first direction X, the interconnection member 20 is disposed on the battery cells 10 and electrically connects adjacent battery cells 10, a plurality of conductive connection layers 30 are disposed between one interconnection member 20 and the battery cells 10 and are arranged at intervals, the interconnection member 20 is electrically connected with the battery cells 10 through the conductive connection layers 30, and a gap 11 is provided between at least part of the positions between the two adjacent conductive connection layers 30 and between the interconnection member 20 and the battery cells 10.

In the embodiment of the application, the interconnection piece 20 is arranged on the surface of the battery piece 10, so that the interconnection piece 20 is used for realizing the electrical connection of the adjacent battery pieces 10, the battery pieces 10 are connected to form a string, the conductive connection layer 30 is arranged between the interconnection piece 20 and the battery pieces 10, the interconnection piece 20 is electrically connected with the battery pieces 10 through the conductive connection layer 30, and at least part of the area between the interconnection piece 20 and the battery pieces 10 is provided with the gap 11. In this way, an optical cavity effect can be formed at the gap 11, so that stray light can irradiate into the gap 11 and undergo multiple reflections on the surface of the cell 10 and the surface of the interconnection piece 20, resonance enhancement is generated, and the stray light is absorbed and utilized by the cell 10, and therefore, the light absorptivity of the cell 10 can be increased, and the efficiency of the photovoltaic module is improved. In addition, the photovoltaic module structure can be realized by optimizing the local structure in the photovoltaic module based on the existing process without introducing new equipment and new materials, and the product cost is not increased.

Specifically, as shown in fig. 2, in the process of manufacturing the photovoltaic module, the plurality of battery pieces 10 are connected in series along the first direction X to form a battery string, and then the plurality of battery strings are connected in series and parallel along the second direction Y to form a battery layer, so that the plurality of battery pieces 10 can be connected to form a series circuit through the plurality of interconnects 20. The surface of the battery sheet 10 is provided with electrodes (not shown in the drawing), the interconnection 20 is electrically connected to the electrodes, and a conductive connection layer 30 is provided between the interconnection 20 and the electrodes, whereby the connection performance of the interconnection 20 to the electrodes can be improved by the conductive connection layer 30. At a position between the two conductive connection layers 30, a gap 11 is formed between at least part of the positions between the interconnection piece 20 and the battery piece 10, so that a similar fabry-perot cavity structure is formed between the interconnection piece 20 and the battery piece 10, the surface of the interconnection piece 20 and the surface of the battery piece 10 serve as two reflecting surfaces, when stray light in the photovoltaic module enters the gap 11, interference, resonance and other interaction can be formed by multiple reflection of the surface of the interconnection piece 20 and the surface of the battery piece 10, and a resonance enhancement effect, which is also called as an optical cavity effect, exists for light in a specific wavelength range.

In the process of the photovoltaic module, when the interconnection piece 20 is utilized to interconnect the battery piece 10, a gap 11 is reserved at a position between two adjacent conductive connection layers 30, namely between the interconnection piece 20 and two connection points of the battery piece 10, at least a part of the position between the interconnection piece 20 and the battery piece 10, so that a light cavity effect can be formed at the gap 11, the absorption of the battery piece 10 to stray light is increased, the light management efficiency inside the photovoltaic module is improved, and the conversion efficiency of the photovoltaic module is further improved.

It can be understood that the plurality of battery pieces 10 are electrically connected through the interconnection piece 20 to form a battery string, the battery strings are connected in series and parallel to form a battery layer of the photovoltaic module, and then the packaging adhesive film layer, the front plate and the back plate are paved on two sides of the battery layer, and the photovoltaic module can be prepared through lamination. For example, 12 cells can be connected in series and parallel to form a cell layer of the photovoltaic module.

Wherein, positive and negative thin gate electrodes extending along the second direction Y and arranged along the first direction X are arranged on the surface of the battery plate 10 to collect the current generated by the battery plate 10. The surface of the battery 10 is also provided with pads to electrically connect the positive and negative thin gate electrodes and the interconnect 20. Preferably, a main gate or a conductive connection line may be further provided between the pads.

The conductive connection layer 30 is formed of a conductive material and mainly serves as an electrical connection between the interconnect 20 and the electrode on the battery cell 10. In practical application, the interconnection piece 20 and the upper electrode of the battery piece 10 can be connected by adopting a welding mode, and a plurality of electric connection points are formed on the electrode at intervals by adopting a welding-assisting material (such as solder paste), the electric connection layers 30 can be in one-to-one correspondence with the electric connection points, the electric connection between the interconnection piece 20 and the battery piece 10 can be realized by welding the interconnection piece 20 and the electric connection points through the electric connection layers 30, and a structure formed after welding at the electric connection points is the electric connection layer 30.

The interconnect 20 may be a solder strip comprising wires of a core and a peripheral soldering aid layer, or may be an electrical connection layer on a conductive back plate. When the interconnection 20 is a solder ribbon, the extending direction of the interconnection 20, i.e., the length direction thereof, is the same as the first direction X.

In some embodiments, as shown in fig. 1, by setting the width of the interconnection piece 20 to be greater than the thickness of the interconnection piece 20, so that the interconnection piece 20 has a flat structure, at this time, the surface of the interconnection piece 20 facing the battery piece 10 is a plane-like surface, so that more light entering the gap 11 can be reflected by the surface of the interconnection piece 20 than an arc surface, thereby forming an optical cavity effect.

The width of the interconnect 20 refers to an average width value of the interconnect 20 in a direction parallel to the surface of the battery sheet 10 and perpendicular to the extending direction of the interconnect 20, and the thickness of the interconnect 20 refers to an average thickness value of the interconnect 20 in a direction perpendicular to the surface of the battery sheet 10.

Specifically, the width of the interconnect 20 is 0.2mm-1mm, for example, the width of the interconnect 20 may be set to 0.2mm, 0.3mm, 0.5mm, 0.6mm, 0.7mm, 1mm, etc. By arranging the width of the interconnection piece 20 between 0.2mm and 1mm, the optical cavity effect can be ensured at the gap 11 between the interconnection piece 20 and the battery piece 10, and in addition, the phenomenon that the surface of the battery piece 10 is blocked by the excessively wide interconnection piece 20 is avoided, and the material waste is avoided.

Specifically, the thickness of the interconnect 20 is 0.1mm to 0.5mm. For example, the thickness of the interconnect 20 may be set to 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, or the like. The thickness of the interconnection piece 20 is 0.1 mm-0.5 mm, so that the interconnection piece 20 is ensured to have a certain thickness to play a role in conducting current between the battery pieces 10, and meanwhile, the formation of the gap 11 is prevented from being influenced by the fact that the interconnection piece 20 is too thin and low in strength and is easy to be stressed and deformed in the assembly machining process. In addition, it is also avoided that the interconnection 20 is too thick, so that the battery piece 10 is prone to local hidden cracking during lamination due to a large height difference on the surface of the battery piece 10.

Illustratively, the interconnect 20 of the present application may be formed with a flat solder strip to electrically connect the flat solder strip to the electrode on the surface of the battery cell 10, and a gap 11 is provided at least partially between the flat solder strip and the surface of the battery cell 10, such that an optical cavity effect is formed at the gap 11.

It will be appreciated that in the optical cavity effect, after light is reflected multiple times in the cavity (i.e. the gap 11 in the present application), only light satisfying the optical path difference being an integer multiple of half the wavelength can form a stable standing wave, i.e. satisfying the resonance condition 2nl=mλ, where n is the refractive index of the medium in the cavity, L is the cavity length (i.e. the height of the gap 11 in the present application), λ is the wavelength of light in vacuum, and m is a positive integer (resonance order). Light meeting the condition is continuously superposed and enhanced in the cavity, and light not meeting the condition is gradually attenuated due to interference cancellation. This screening action allows the cavity to only allow light of a specific wavelength (resonant wavelength) to exist stably, forming a formant. It follows that in the optical cavity effect, the cavity length (i.e. the height of the gap 11) of the cavity directly influences the wavelength of the light that is able to resonate.

Alternatively, as shown in fig. 1, the height L of the gap 11 is less than or equal to 100 μm and greater than or equal to 0 μm in the thickness direction of the battery sheet 10. Preferably, the height L of the gap 11 is in the range of 0.36 μm to 89.3. Mu.m.

On the one hand, the inventor respectively tests the strong resonance wavelength distribution corresponding to the optical cavity effect generated under different gap 11 heights through research and analysis, selects the distribution of the first three strongest resonance wavelengths under the corresponding conditions, and the specific result is shown in fig. 9. From the test results in the figure, it can be seen that the coverage of the strong resonance wavelength is between 500nm and 1000nm when the height L of the gap 11 is less than or equal to 100 μm, whereas the coverage of the resonance wavelength is only significantly strong resonance in the shorter wavelength range when the height L of the gap 11 is greater than 100 μm. Therefore, in the present application, the height L of the gap 11 is set to be less than or equal to 100 μm, so as to ensure that the wavelength of the resonant light cavity can cover the wavelength range that can be absorbed by the battery piece 10 as much as possible, so as to improve the light management efficiency inside the photovoltaic module, thereby improving the performance of the photovoltaic module.

On the other hand, in the optical cavity effect, besides the distribution range of the resonant wavelength, the number of wave packets in the resonant cavity needs to be considered, wherein the wave packets refer to localized fluctuation states formed by superposition of a plurality of waves with different frequencies and different phases. As the height L of the gap 11 increases, the number of wave packets generated by the optical cavity effect increases, and the total energy of resonance tends to decrease, and the energy concentration decreases greatly, so that the resonance enhancing effect of the optical cavity effect on stray light is reduced. And, as the height L of the gap 11 increases, the longer the distance the light travels in the cavity, the greater the energy loss of the light during traveling, and the resonance energy decreases. Therefore, the height L of the gap 11 is less than or equal to 100 mu m, so that the energy attenuation of light transmission in the light effect is reduced, and the resonance enhancement effect of the light cavity effect on stray light is ensured.

In addition, since the battery sheet 10 itself has the characteristics of strong absorption and weak penetration of short waves, that is, short waves are easily absorbed by the battery sheet 10 and long waves are easily penetrated through the battery sheet 10. According to the application, the height L is less than or equal to 100 mu m, so that the generated optical cavity effect can cover a wider wavelength range, and thus the optical cavity effect generated at the gap 11 not only can generate a light management effect on stray light directly irradiated into the gap 11, but also can generate a light management effect on long-wavelength light penetrating through the cell 10, thereby increasing the absorption and utilization rate of the cell 10 on light.

Specifically, the height L of the gap 11 may be set to 0.1 μm, 0.2 μm, 0.36 μm, 0.5 μm, 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 89.3 μm, 90 μm, 100 μm, etc.

It can be understood that the measurement of the height L of the gap 11 in the present application may be performed by measuring the linear distance from the side of the battery piece 10 facing the gap 11 to the side of the interconnection 20 facing the gap 11 along the thickness direction of the battery piece 10, and measuring a plurality of distance values, and averaging the plurality of distance values of one gap 11 to obtain the height L of the gap 11.

Alternatively, the height L of the gap 11 satisfies the following formula:

Where n is the refractive index of the medium in the gap 11, m is a positive integer (representing the resonant order), λ ₁ is the wavelength of light available to the battery piece 10 entering the gap 11, and Δλ is the minimum interval between adjacent resonant modes.

It will be understood that n in the above formula is the refractive index of the medium in the gap 11, where n is related to the substance in the gap 11 in the actual photovoltaic module, for example, when the gap 11 is filled with the encapsulation adhesive layer 40, where n refers to the refractive index of the encapsulation adhesive layer 40. M in the above formula represents a resonance order, represents an "order" of interference enhancement, and generally takes a positive integer, for example, m=1, 2, 3.λ1 in the above formula is the wavelength of the available light of the battery piece 10 entering the gap 11, and the wavelength of the available light of the battery piece 10 is generally in the range of 400 nm-1200nm, but in consideration of the optical cavity effect, the value of λ ₁ in the application is set to 400 nm-1000nm. The delta lambda in the formula is the minimum interval between adjacent resonance modes, namely the minimum frequency difference between resonance frequencies (longitudinal modes) which exist in the optical cavity stably, and the value of delta lambda is set to be 4nm-5nm in the application.

In the embodiment of the application, after light is reflected in the gap 11, stable standing waves can be formed only when certain resonance conditions are met, and the resonance effect of the light is influenced by factors such as the height L of the gap, the refractive index of a dielectric material in the gap 11 and the like, and the association relation between the height L of the gap 11 and the wavelength of available light entering the gap 11 and the refractive index of the dielectric material in the gap 11 is established, so that the height L of the gap 11 is flexibly set according to the application scene of an actual assembly, thereby ensuring that stable and effective optical cavity effects can be formed, and further improving the conversion efficiency of the photovoltaic assembly.

Alternatively, as shown in fig. 5, along the extending direction of the interconnection member 20, the gap 11 has at least a first position a and a second position b, and the height of the gap 11 at the first position a is greater than the height at the second position b.

It will be appreciated that, based on the foregoing analysis, the different heights of the gap 11 can generate resonance enhancement effects on light with different wavelengths, so that the heights L at least two different positions in the gap 11 are not equal, so that the same gap can generate resonance enhancement effects on light with different wavelengths, and absorption of the photovoltaic module on light with different wavelengths can be improved.

In some embodiments, the gap 11 has a height difference between 0.1 μm and 88 μm at the first position a and the second position b. By setting the height difference between two different positions of the gap 11 between 0.1 μm and 88 μm, the vibration enhancement effect on the light with different wavelengths can be ensured at different positions in the gap 11, so that the absorption of the photovoltaic module on the light with different wavelengths is improved.

Illustratively, the height difference may be set to 0.1 μm, 0.5 μm, 1 μm, 5 μm, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 88 μm, etc.

In some embodiments, there are height differences within one of the gaps 11 at least at 3 locations. By arranging the gaps 11 with at least 3 height differences, the gaps 11 can generate vibration enhancement effect on more lights with different wavelengths, so that the full absorption and utilization of the photovoltaic module to sunlight which is a full-wave band light source are facilitated.

Alternatively, as shown in fig. 5, a plurality of conductive connection layers 30 are arranged between the interconnection 20 and the battery cell 10 at intervals along the extending direction of the interconnection 20, a gap 11 is formed between two adjacent conductive connection layers 30, and at least two gaps 11 are formed under one interconnection 20.

In the embodiment of the application, gaps 11 are formed between different parts of the same interconnection piece 20 and the battery piece 10, so that a light cavity effect can be generated at different gaps 11, and further the light absorptivity of different positions in the photovoltaic module is improved, and the overall conversion efficiency of the photovoltaic module is improved.

In some embodiments, as shown in fig. 5, the interconnect 20 is in partial contact with the battery plate 10 between portions of adjacent conductive connection layers 30. By locally contacting the interconnection member 20 with the battery piece 10, on one hand, the interconnection member 20 can be locally supported at the contact position, and on the other hand, the height of the gap 11 can be changed corresponding to the gap 11 existing around the contact position, so that the resonance enhancement effect on light with different wavelengths is also facilitated.

In some embodiments, as shown in fig. 1, an insulating layer (not shown in the drawing) is further disposed between the interconnection 20 and the battery cell 10, the interconnection 20, the conductive connection layer 30, and the insulating layer form a gap 11.

In the embodiment of the application, the insulating layer is arranged on the surface of the battery piece 10 to insulate and protect a part of the structure on the surface of the battery piece 10, so that at least a part of the insulating layer is positioned between the interconnection piece 20 and the battery piece 10, the gap 11 is formed by the battery piece 10, the interconnection piece 20, the conductive connecting layer 30 and the insulating layer together, the conductive connecting layer 30 and the insulating layer can refract or reflect light, and the optical cavity effect at the gap 11 can be enhanced. The battery plate 10 and the interconnection 20 can serve as main reflective and refractive bodies, and the conductive connection layer 30 and the insulating layer can serve as supports to form the gap 11 and serve as auxiliary refractive and reflective functions.

In some embodiments, the insulating layer fills at least a portion of the gap 11 between the interconnect 20 and the battery cell 10. Specifically, the insulating layer may be disposed on the surface of the battery cell 10 directly under the interconnection 20 to fill at least part of the gap 11 between the interconnection 20 and the battery cell 10, so that after the light enters the gap 11, the light can be refracted by the insulating layer, thereby generating an optical cavity effect in the gap 11.

In other embodiments, the insulating layer is disposed on the sides of the interconnect 20. That is, an insulating layer is provided between at least one side of the interconnect 20 in the width direction and the battery cell 10, or an insulating layer is provided between at least one side of the interconnect 20 in the length direction and the battery cell 10. In this way, the insulating layer, the battery plate 10, the interconnection member 20, and the conductive connection layer 30 may enclose a cavity, so as to generate an optical cavity effect in the cavity. Meanwhile, stray light can be refracted into the cavity through the insulating layer on the side surface of the interconnection piece 20, so that the light grabbing effect is achieved.

Of course, the insulating layers may be disposed under the interconnection element 20 and on both sides, and the specific disposition positions of the insulating layers may be flexibly set according to actual needs, which is not limited herein.

Alternatively, as shown in fig. 6, the interconnection member 20 has a concave-convex structure 201 on a side surface facing the gap 11. By arranging the concave-convex structure 201 on the surface of the interconnection piece 20 facing the gap 11, the diffuse reflection effect of the surface of the interconnection piece 20 on the light is improved, so that more light is captured into the gap 11 to form the optical cavity effect. Meanwhile, the concave-convex structure 201 is arranged on the surface of the interconnection piece 20, so that the heights of the gaps 11 at different positions in the gaps 11 can be changed, and therefore resonance enhancement can be generated on light with different wavelengths, and the absorption of the photovoltaic module on the light with different wavelengths can be improved.

Alternatively, the surface of the battery piece 10 facing the gap 11 has a concave-convex structure 201. By arranging the battery piece 10 with the concave-convex structure 201 on the surface facing the gap 11, the diffuse reflection effect of the surface of the battery piece 10 on light is improved, so that more light is captured into the gap 11 to form an optical cavity effect. Meanwhile, the concave-convex structure 201 is arranged on the surface of the battery piece 10, and the heights of the gaps 11 at different positions in the gaps 11 can be changed, so that resonance enhancement can be generated on light with different wavelengths, and the absorption of the photovoltaic module on the light with different wavelengths can be improved.

Alternatively, as shown in FIG. 6, the height difference H1 between the highest point and the lowest point in the rugged structure 201 is 0.05 μm to 10 μm in the thickness direction of the battery sheet 10. For example, the height difference may be set to 0.05 μm, 0.1 μm, 0.5 μm,1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm,10 μm, or the like.

In the embodiment of the application, the height difference between the highest point and the lowest point in the concave-convex structure 201 formed on the surface of the battery piece 10 or the interconnection piece 20 is in the range of 0.05 μm-10 μm, so that the diffuse reflection effect of light can be ensured through the concave-convex structure 201, and the heights of different positions in the gap 11 can be changed through the concave-convex structure 201. If the height difference is too large, a relatively sharp protrusion structure exists on the surface of the battery piece 10 or the interconnection piece 20, so that the battery piece 10 or the interconnection piece 20 is easily damaged locally in the processing process of the component, and the performance of the component is affected.

In some embodiments, the interconnect 20 has protruding tin particles on a side surface facing the gap 11. By having the interconnect 20 have protruding tin particles on the side surface facing the gap 11, light impinging on the surface of the interconnect 20 can be reflected toward the battery piece 10, which is advantageous for enhancing the optical cavity effect, because the tin metal particle surface has a high reflectivity. In addition, the surface of the interconnection piece 20 is provided with the protruding tin particles, so that the heights of gaps at different positions between the interconnection piece 20 and the battery piece 10 are different, and therefore resonance enhancement effect can be generated on light with different wavelengths, and absorption of the photovoltaic module on the light with different wavelengths is improved.

In other embodiments, the side surface of the battery plate 10 facing the gap 11 has a textured structure. By arranging the textured structure on the surface of the side, facing the gap 11, of the battery piece 10, the surface of the battery piece 10 is in a large-area and regular concave-convex structure 201, so that the diffuse reflection effect of the surface of the battery piece 10 on light rays can be improved, and more light rays can be captured into the gap 11 to form a light cavity effect. Meanwhile, the heights of the gaps 11 at different positions in the gaps 11 can be changed, so that resonance enhancement can be generated on light with different wavelengths, and the absorption of the photovoltaic module on the light with different wavelengths is improved.

In still other embodiments, the conductive connection layer 30 has an undulating structure 201 on a side surface facing the gap 11. By arranging the conductive connection layer 30 to be in the concave-convex structure 201 towards one side surface of the gap 11, light can be reflected to one side surface of the cell 10 towards the gap 11 when the light irradiates to the surface of the conductive connection layer 30, or one side surface of the interconnection piece 20 towards the gap 11, so that the light can generate a light cavity effect in the gap 11, and the absorption of the light of the photovoltaic module can be improved.

Optionally, a plurality of gaps 11 are formed between the same interconnect 20 and the battery plate 10 along the extending direction of the interconnect 20, and at least two gaps 11 are unequal in height. By forming a plurality of gaps 11 arranged at intervals between the same interconnection piece 20 and the battery piece 10, the optical cavity effect is generated by utilizing different gaps 11. Meanwhile, the heights of at least two gaps 11 are unequal, and different gaps 11 can generate resonance enhancement effect on light with different wavelengths, so that the absorption effect of one interconnection piece 20 area on light with different wavelengths can be improved, the utilization rate of the whole interconnection piece 20 on the sunlight, namely the full-band light source, is improved, and the absorption enhancement effect on light with single wavelength or a narrow wavelength range is avoided.

It should be noted that, the unequal heights of the two gaps 11 means that the average height of one gap 11 is unequal to the average height of the other gap 11, specifically, the linear distance between the surface of the battery piece 10 and the surface of the interconnection piece 20 at each gap 11 is measured along the thickness direction of the battery piece 10, and the measured distance values are averaged to obtain the height of the corresponding gap 11.

Optionally, as shown in fig. 2, the battery piece 10 is provided with a plurality of interconnects 20, where the plurality of interconnects 20 includes a first interconnect 20a and a second interconnect 20b, one gap 11 formed by the first interconnect 20a corresponding to the battery piece 10 is a first gap, one gap 11 formed by the second interconnect 20b corresponding to the battery piece 10 is a second gap, and heights of the first gap and the second gap are unequal.

In the embodiment of the application, the heights of the gaps 11 correspondingly formed by the different interconnection pieces 20 on the same battery piece 10 are not equal, so that the resonance enhancement effect is generated on the light with different wavelengths by using the different gaps 11 corresponding to the different interconnection pieces 20 on the battery piece 10, and therefore, the utilization rate of the whole battery piece 10 to the sunlight full-band light source can be improved.

The height of the first gap here refers to the average height of the first gap in the thickness direction of the battery sheet 10, and the height of the second gap is the same.

Optionally, the plurality of battery pieces 10 include a first battery piece 10a and a second battery piece 10b, one gap 11 formed on the first battery piece 10a is a third gap, one gap 11 formed on the second battery piece 10b is a fourth gap, and the heights of the third gap and the fourth gap are not equal.

In the embodiment of the application, the heights of the gaps 11 formed on the different battery pieces 10 are not equal, so that the gaps 11 formed on the different battery pieces 10 on the photovoltaic module can generate resonance enhancement effect on light with different wavelengths, and the utilization rate of the whole photovoltaic module on the sunlight full-band light source can be improved.

The height of the third gap here refers to the average height of the third gap in the thickness direction of the battery sheet 10, and the height of the fourth gap is the same.

Optionally, as shown in fig. 5, the photovoltaic module further includes an encapsulation adhesive layer 40, and at least part of the gap 11 is filled with the encapsulation adhesive layer 40.

In the preparation process of the photovoltaic module, the packaging glue layer 40 is adopted to package and protect the battery piece 10, and the packaging glue layer 40 is filled into the gap 11 formed by the interconnection piece 20 and the battery piece 10, so that on one hand, the height difference of different positions in the gap 11 can be changed through the packaging glue layer 40, and on the other hand, resonance enhancement effect of the gap 11 on light with different wavelengths can be improved, and on the other hand, stray light in the photovoltaic module can be refracted into the gap 11 through the packaging glue layer 40, so that the effect of capturing light is achieved, the light cavity effect at the gap 11 is enhanced, and the absorption of the photovoltaic module on light is improved.

Specifically, the photovoltaic module may include a front plate, a back plate, a battery layer and a packaging adhesive layer 40, the battery layer is formed by connecting a plurality of battery pieces 10 in series and parallel through an interconnection piece 20, the front plate and the back plate are stacked, the packaging adhesive layer 40 is arranged between the front plate and the back plate, the battery layer is embedded in the packaging adhesive layer 40, and a packaging protection effect can be formed on the battery layer through the packaging adhesive layer 40.

The encapsulation adhesive layer 40 may be made of a transparent material, for example, one or two of ethylene-vinyl acetate copolymer (EVA) and polyolefin elastomer (POE) may be selected, and of course, other transparent encapsulation materials may be selected, and may be flexibly selected according to actual needs, which is not limited herein.

In some embodiments, the photovoltaic module of the present application is a double-sided glass photovoltaic module, i.e., the front and back sheets in the photovoltaic module are both provided as glass. So that light can penetrate through the glass on the front and back of the module to enter the photovoltaic module, so that the front and back of the battery piece 10 can both receive light, and the absorption and utilization rate of the photovoltaic module to light can be improved by matching with the light cavity effect of the gap 11 formed on the surface of the battery piece 10, thereby improving the efficiency of the photovoltaic module.

In some embodiments, a layer of encapsulant 40 is provided between the sides of the interconnect 20 and the battery cells 10. By providing the encapsulation glue layer 40 between the side surface of the interconnection piece 20 and the battery piece 10, a closed or semi-closed cavity space is formed by enclosing the interconnection piece 20, the battery piece 10, the electrical connection layer and the encapsulation glue layer 40, and thus an optical cavity effect can be generated in the cavity space.

It should be noted that the side surface of the interconnection member 20 described herein includes at least one side of the interconnection member 20 in the length direction thereof, or at least one side of the interconnection member 20 in the width direction thereof.

In some embodiments, the index of refraction of the encapsulant layer 40 is 1.4-1.5. The refractive index of the packaging adhesive layer 40 is between 1.4 and 1.5, so that the refractive index of the packaging adhesive layer 40 is between the refractive index of the battery piece 10 and the refractive index of the interconnection piece 20, the refractive effect of the packaging adhesive layer 40 on light can be improved, and the battery piece 10, the packaging adhesive layer 40 and the interconnection piece 20 are matched with each other, so that more stray light can be refracted into a gap 11 between the battery piece 10 and the interconnection piece 20, and light cavity effect can be generated.

Specifically, the refractive index of the encapsulation adhesive layer 40 may be set to 1.4, 1.43, 1.45, 1.5, etc., and the refractive index of the encapsulation adhesive layer 40 varies with the selected material and may be flexibly set according to actual needs, which is not limited herein.

In some embodiments, the encapsulation glue layer 40 is located within the gap 11 at a height of 0.5 μm to 100 μm. By setting the height range of the encapsulation glue layer 40 in the gap 11 between 0.5 μm and 100 μm, so that the encapsulation glue layer 40 partially fills the gap 11, thereby not only ensuring that more stray light can be captured into the gap 11 to form a light cavity effect by utilizing the refraction effect of the encapsulation glue layer 40, but also avoiding the reflection of light between the interconnection piece 20 and the battery piece 10 due to the too thick encapsulation glue layer 40.

The height of the encapsulation glue layer 40 located in the gap 11 may be set to 0.5 μm, 1 μm, 5 μm, 10 μm, 20 μm, 50 μm, 80 μm, 100 μm, etc. by way of example.

In some embodiments, as shown in fig. 3, the photovoltaic module has intersecting first and second directions X and Y, each of which is parallel to one side surface of the cell sheet 10 where the interconnect 20 is disposed. The conductive connection layer 30 has a first inclined plane 301 along at least one side of the first direction X, and a first included angle A1 is formed between the first inclined plane 301 and the surface of the battery piece 10.

In the application, at least one side of the conductive connection layer 30 along the first direction X has a first inclined plane 301, a certain inclination angle is formed between the first inclined plane 301 and the surface of the cell 10, when the light entering the photovoltaic module irradiates the first inclined plane 301, the light is reflected to the surface of the cell 10 facing the gap 11 or the surface of the interconnection piece 20 facing the gap 11 through the first inclined plane 301, and thus, the optical cavity effect can be generated in the gap 11. Thus, the first inclined surface 301 of the conductive connection layer 30 can act as a "catch" for light, so that more stray light enters the gap 11 to generate a cavity effect.

In other embodiments, as shown in fig. 4, the conductive connection layer 30 has a second slope 302 along at least one side of the second direction Y.

In the application, at least one side of the conductive connecting layer 30 along the second direction Y is provided with the second inclined plane 302, a certain inclined angle is formed between the second inclined plane 302 and the surface of the battery piece 10, when the light entering the photovoltaic module irradiates the second inclined plane 302, the light is reflected to the battery piece 10 or the interconnection piece 20 by the second inclined plane 302, so that the light utilization rate can be improved, and meanwhile, part of the light reflected by the second inclined plane is directly utilized by the battery piece 10, and part of the light enters the gap 11 to be further utilized.

Optionally, as shown in fig. 3 and 4, a first included angle A1 is formed between the first inclined plane 301 and the surface of the battery piece 10, a second included angle A2 is formed between the second inclined plane 302 and the surface of the battery piece 10, and the first included angle A1 is not equal to the second included angle A2. By setting the angle formed by the first inclined plane 301 and the second inclined plane 302 relative to the surface of the battery piece 10 to be different, the light rays with different incident angles can be excessively reflected by using the different inclined planes of the conductive connecting layer 30, so that more light rays can be captured into the gap 11 or directly absorbed by the battery piece 10, and the absorption and utilization rate of the photovoltaic module to stray light can be improved.

In some embodiments, the surface roughness of the first slope 301 is greater than or equal to 20nm. By setting the surface roughness of the first inclined plane 301, the first inclined plane 301 can generate diffuse reflection effect, so that more stray light can be reflected into the gap 11, and the utilization rate of the photovoltaic module to the stray light is improved.

In other embodiments, the surface roughness of the second bevel 302 is greater than or equal to 20nm. By setting the surface roughness of the second inclined plane 302, the second inclined plane 302 can generate diffuse reflection effect, so that more stray light can be reflected into the gap 11, and the utilization rate of the photovoltaic module to the stray light is improved.

Alternatively, as shown in fig. 5, the battery sheet 10 is provided with an electrode 50 at a position corresponding to the gap 11, and the electrode 50 protrudes from the surface of the battery sheet 10.

In the embodiment of the application, the partial electrode 50 is stored in the gap 11, and the partial electrode 50 protrudes from the surface of the corresponding battery piece 10, and as the surface of the electrode 50 can reflect light, the height difference of different positions in the gap 11 is changed by arranging the electrode 50 in the gap 11 so as to generate resonance enhancement effect on light with different wavelengths, thereby improving the utilization rate of the photovoltaic module on sunlight which is a full-band light source.

The partial electrode 50 located in the gap 11 may be in contact with the surface of the interconnect 20 facing the gap 11, or may be not in contact with the surface, and may be flexibly arranged according to the actual structure, and is not limited thereto.

It will be appreciated that the electrode 50 located in the gap 11 may be at least one of a current collecting electrode for collecting the carriers generated by the battery cell 10 and a bus electrode for collecting the carriers collected by the current collecting electrode and transmitting the same to the interconnect 20.

Alternatively, as shown in FIG. 5, the electrode 50 protrudes from the surface of the battery sheet 10 to a height of 2 μm to 35 μm. For example, the height of the electrode 50 protruding from the surface of the battery sheet 10 may be set to 2 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, or the like.

In the embodiment of the present application, the protruding height range of the electrode 50 located in the gap 11 is set so that the electrode 50 occupies part of the gap space, so that it is ensured that light can be reflected multiple times between the interconnection piece 20, the battery piece 10 and the electrode 50 in the gap 11 to generate the optical cavity effect, and meanwhile, the protruding height of the electrode 50 is prevented from being too high to occupy more gaps 11, which is unfavorable for light resonance in the gap 11.

In some embodiments, the battery cell 10 is a back contact battery cell 10, an electrode is disposed on the back surface of the battery cell 10, a conductive connection layer 30 is disposed on the electrode, and the interconnect 20 is electrically connected to the electrode through the conductive connection layer 30. And a gap 11 is formed between at least part of the positions of the interconnection piece 20 and the battery piece 10, so that the gap 11 can be used for generating an optical cavity effect to improve the absorption and utilization rate of the back surface of the battery piece 10 to light.

In other embodiments, the battery 10 is a double-sided battery 10, electrodes are disposed on the front and back sides of the battery 10, conductive connection layers 30 are disposed on the electrodes, and the interconnection 20 is electrically connected to the electrodes through the conductive connection layers 30. Furthermore, the gaps 11 are formed on the front and back sides of the battery piece 10, so that the optical cavity effect can be generated by using the gaps 11, and the absorption and utilization rate of light on the front and back sides of the battery piece 10 can be improved. Also, the provision of the conductive connection layer 30 may also improve the connectivity of the electrode with the interconnect 20.

It will be appreciated that the electrodes provided on the front and/or back of the battery sheet include a current collecting electrode for collecting the carriers generated by the battery sheet 10 and a bus electrode for collecting the carriers collected by the current collecting electrode and transmitting them to the interconnect 20.

It should be noted that, the battery cell 10 in the present application may be a battery cell 10 with a main grid, that is, a current collecting electrode and a current collecting electrode are simultaneously disposed on the surface of the battery cell 10, and the interconnect 20 is electrically connected to the current collecting electrode through the conductive connection layer 30. Alternatively, the battery sheet 10 in the present application may be a battery sheet 10 without a main grid, that is, only a current collecting electrode is provided on the surface of the battery sheet 10, and the interconnection 20 is electrically connected to the current collecting electrode through the conductive connection layer 30. The specific electrode arrangement structure can be flexibly arranged according to actual needs, and is not limited herein.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the spirit and scope of the application as defined by the appended claims and their equivalents.

Claims

1. A photovoltaic module is characterized by comprising a plurality of battery pieces and an interconnection piece;

the plurality of battery pieces are arranged along a first direction, and the interconnection piece is arranged on the battery pieces and is electrically connected with the adjacent battery pieces;

2. The photovoltaic module according to claim 1, wherein a height of the gap is 100 μm or less and 0 μm or more in a thickness direction of the cell sheet;

or, the height of the gap is in the range of 0.36 μm to 89.3. Mu.m.

3. The photovoltaic module of claim 1, wherein the height L of the gap satisfies the formula:

4. The photovoltaic module of claim 1, wherein the gap has at least a first position and a second position along the direction of extension of the interconnect,

The gap has a height at the first location that is greater than a height at the second location;

5. The photovoltaic module according to claim 1, wherein a plurality of conductive connection layers are arranged between the interconnection piece and the battery piece at intervals along the extending direction of the interconnection piece, the gaps are arranged between two adjacent conductive connection layers, and at least two gaps are arranged below one interconnection piece;

6. The photovoltaic module of claim 1, wherein an insulating layer is further disposed between the interconnect and the cell, the interconnect, the conductive connection layer, and the insulating layer forming the gap.

7. The photovoltaic assembly of claim 6, wherein the insulating layer fills at least a portion of a gap between the interconnect and the cell or is disposed on a side of the interconnect.

8. The photovoltaic module of claim 1, wherein a side surface of the interconnect facing the gap is of a relief structure;

9. The photovoltaic module according to claim 8, wherein a height difference between the highest point and the lowest point in the rugged structure is 0.05 μm to 10 μm in a thickness direction of the battery sheet.

10. The photovoltaic module of claim 1, wherein a side surface of the interconnect facing the gap has protruding tin particles;

11. The photovoltaic module of claim 1, wherein a side surface of the conductive connection layer facing the gap is in a relief structure.

12. The photovoltaic module of claim 1, wherein the photovoltaic module comprises at least one of:

13. The photovoltaic module of any of claims 1-12, further comprising an encapsulation layer, wherein at least a portion of the gap is filled with the encapsulation layer;

14. The photovoltaic module of claim 13, wherein the encapsulant layer has a refractive index of 1.4-1.5;

15. The photovoltaic module of any of claims 1-12, wherein the conductive connection layer has a first bevel along at least one side of the first direction;

16. The photovoltaic module of claim 15, wherein a first angle is formed between the first bevel and the cell surface, a second angle is formed between the second bevel and the cell surface, and the first angle is not equal to the second angle;

17. The photovoltaic module according to any one of claims 1 to 12, wherein an electrode is provided on the cell at a position corresponding to the gap, the electrode protruding from a surface of the cell.

18. The photovoltaic module of claim 17, wherein the electrode protrudes from the surface of the cell by a height of 2-35 μm.

19. The photovoltaic module of any of claims 1-12, wherein the interconnect is a flat solder strip;

20. The photovoltaic module according to any one of claims 1 to 12, wherein the back surface of the battery sheet is provided with an electrode, or both the front surface and the back surface of the battery sheet are provided with an electrode, and the interconnect is electrically connected to the electrode through the conductive connection layer;

And/or the photovoltaic module is a double-sided glass photovoltaic module.

21. A photovoltaic system comprising a plurality of electrically connected photovoltaic modules employing the photovoltaic module of any one of claims 1-20.