Heat-spot-resistant battery piece array and heat-spot-resistant photovoltaic module
By adopting an anti-hot spot cell array design in photovoltaic modules and constructing a dual protection circuit using busbars and bypass components, the problem of cell overheating caused by hot spot effect is solved, improving the reliability and durability of the modules, while reducing production losses and mechanical damage risks.
Patent Information
- Application Number
- CN202511218051.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-28
- Publication Date
- 2025-10-31
AI Technical Summary
Existing photovoltaic modules are prone to hot spot effects when shaded or with cell defects, leading to localized overheating of the cells, melting of solder joints, and aging of encapsulation materials, which affects the output power and lifespan of the modules. In addition, traditional interconnect designs have risks of current transmission loss and mechanical stress.
The design employs an anti-hot spot battery cell array, forming a power generation unit by connecting battery strings in parallel through a busbar, and connecting a bypass component in parallel. Combined with conductive tape and positioning tape, a dual protection circuit is constructed, providing an alternative current path and fixing the position of the battery strings, reducing connection points and current transmission losses.
It improves the long-term power output reliability, durability and safety of photovoltaic modules, reduces current transmission loss and mechanical damage risk, and improves module production efficiency and aesthetics.
Smart Images
Figure CN120882103A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of solar cell technology, and in particular to a hot spot resistant solar cell array and a hot spot resistant photovoltaic module. Background Technology
[0002] Crystalline silicon photovoltaic modules can experience hot spot effects when exposed to shade (such as bird droppings, dust, or tree shade) or when the cells have defects such as microcracks or bubbles. The core mechanism is that some cells, due to uneven illumination or performance mismatch, enter a reverse bias state, forming a "load" area that consumes energy generated by other normally functioning areas. This leads to localized overheating (temperatures can reach several hundred degrees Celsius) in the shaded or defective areas. Hot spot effects can cause localized cell burnout, solder melting, and aging of encapsulation materials, resulting in reduced module output power and shortened lifespan. In extreme cases, it can even cause fires, posing a serious threat to the safety and economic viability of photovoltaic systems.
[0003] In existing technologies, hot spot prevention strategies mostly focus on circuit redundancy design, such as using short interconnects to achieve parallel bridging between adjacent rows of cells. However, short interconnects only cover a local area of adjacent rows, resulting in a long current transmission path in the uncovered back area of the cells, leading to current transmission losses. For low-power modules, the power loss accounts for a higher proportion. When using long interconnects to achieve parallel bridging of multiple rows of cells, the conductive bonding process between the interconnects and the cells is prone to introducing mechanical stress. Especially when using short copper interconnects and solder, a large number of soldering operations can easily cause microcracks or cracks in the thin silicon wafers, affecting the reliability, durability, and safety of use. Summary of the Invention
[0004] The purpose of this invention is to provide a hot spot resistant solar cell array and a hot spot resistant photovoltaic module to solve the problems existing in the prior art and improve the long-term power output reliability, durability and safety of photovoltaic modules.
[0005] To achieve the above objectives, the present invention provides the following solution:
[0006] This invention provides a hot spot resistant solar cell array, including a bypass component, at least one power generation unit, multiple conductive elements, and multiple positioning elements. The power generation unit includes multiple battery strings arranged side-by-side and connected in parallel along a first direction, and each battery string includes multiple battery cells connected in series along a second direction. Each power generation unit has a busbar at both ends along the second direction, and the battery cells at both ends of each battery string along the second direction are electrically connected to the corresponding busbar. The multiple conductive elements are arranged parallel to each other along the second direction, each extending along the first direction, and each conductive element can be face-fitted and electrically connected to the back side of at least one row of battery cells in all the battery strings of the power generation unit. The multiple positioning elements are arranged parallel to each other along the first direction, each extending along the second direction, and adjacent battery strings within the power generation unit are connected through a positioning element. The bypass component is disposed on at least one side of the power generation unit along the first direction, and both ends of the bypass component are electrically connected to the busbars at both ends of the power generation unit, and the bypass component can also be electrically connected to at least one of the conductive elements.
[0007] Preferably, each of the battery cells is a rectangular sheet, the length direction of each battery cell is parallel to the first direction, and the width direction of each battery cell is parallel to the second direction; a main grid extending along the first direction is provided on the long side of the back side of the battery cell, and a plurality of sub-grids extending along the second direction are also provided parallel to the back side of the battery cell, and each of the sub-grids on the back side of the battery cell is connected to the main grid on the back side of the battery cell; the conductive element is electrically connected to each of the sub-grids corresponding to the back side of the battery cell.
[0008] Preferably, each of the conductive components is configured as conductive tape, which is adhered to the back of the corresponding battery cell and electrically conducts to each of the sub-grids on the back of the corresponding battery cell.
[0009] Preferably, each of the positioning components is configured as positioning tape, and each positioning tape is adhered between the back sides of two adjacent battery strings.
[0010] Preferably, the positioning tape is the same color as the backing layer.
[0011] Preferably, the bypass assembly includes a bypass conductor and a plurality of bypass diodes. The bypass conductor extends parallel to the second direction, and each of the bypass diodes is connected in series with the bypass conductor. The two ends of the bypass conductor are respectively connected to the busbars at both ends of the power generation unit. The bypass conductor can also be connected to at least one of the conductive elements, and a bypass diode is connected in series between adjacent conductive points on the bypass conductor.
[0012] Preferably, the bypass conductor is electrically connected to each of the conductive components.
[0013] Preferably, the long sides of adjacent battery cells in the battery string overlap to enable them to be connected in series for conductive connection.
[0014] Preferably, the number of power generation units is set to multiple, and the multiple power generation units are distributed in parallel along the first direction. Each power generation unit is provided with the busbar, the bypass component, multiple conductive components and multiple positioning components. The busbar on one side of an adjacent power generation unit can be electrically conductive so that the multiple power generation units are connected in series.
[0015] The present invention also provides a hot spot resistant photovoltaic module, including a panel layer, a backsheet layer, an encapsulation layer, and the panel layer as described above; the panel layer is fixedly disposed on the front side of the hot spot resistant cell array; the backsheet layer is fixedly disposed on the back side of the hot spot resistant cell array; the panel layer and the backsheet layer are both connected to the hot spot resistant cell array through the encapsulation layer, and both the panel layer and the encapsulation layer are made of transparent insulating material.
[0016] The present invention achieves the following technical effects compared to the prior art:
[0017] The hot spot resistant solar cell array provided by this invention consists of solar cell strings connected in parallel via busbars to form power generation units. Bypass components are connected in parallel between power generation units, and conductive components are used to bridge multiple solar cell strings along a first direction (lateral) to construct a dual protection circuit. When a power generation unit is partially shaded, the lateral conductive components provide an alternative current path to prevent overheating in the shaded area. When a power generation unit is severely shaded, the bypass components maintain overall circuit continuity. This improves the long-term power output reliability, durability, and safety of the photovoltaic module. Furthermore, each conductive component is surface-mounted to the same row of solar cells in the solar cell string, forming a surface-contact current collection network. This reduces losses by shortening the current transmission distance, thereby increasing the module's output power.
[0018] Furthermore, by using conductive tape as the conductive component, which is then adhered to the back of the corresponding solar cell, all sub-grids on the back of the cell are electrically conductive. This reduces the number of connection points, eliminates the need for traditional precision welding steps, improves module production efficiency, avoids microcracks in the silicon wafer caused by high temperatures and pressures during welding, further reduces the risk of mechanical damage to the solar cell, and improves the yield of the photovoltaic module production process. In addition, by connecting adjacent cell strings with positioning components, the relative positions of the cell strings are fixed, preventing displacement between cell strings during lamination and improving the yield of module production.
[0019] The hot spot resistant photovoltaic module provided by this invention encapsulates and protects the hot spot resistant cell array through a panel layer and a backsheet layer. In synergy with the hot spot resistant cell array, it can further improve the reliability, durability and safety of the photovoltaic module. Attached Figure Description
[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0021] Figure 1 This is a schematic diagram of the anti-hot spot solar cell array provided in Embodiment 1 of the present invention;
[0022] Figure 2 This is a schematic diagram of the back side of the battery cell provided in Embodiment 1 of the present invention;
[0023] Figure 3 This is an exploded schematic diagram of the anti-hot spot photovoltaic module provided in Embodiment 2 of the present invention.
[0024] In the diagram: 1-Anti-spot solar cell array; 11-Power generation unit; 111-Battery string; 112-Solar cell; 1121-Main busbar; 1122-Sub-busbar; 113-Bus unit; 12-Conductive component; 13-Positioning component; 14-Bypass assembly; 141-Bypass conductor; 142-Bypass diode; 2-Panel layer; 3-Backsheet layer; 4-Encapsulation layer. Detailed Implementation
[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0026] The purpose of this invention is to provide a hot spot resistant solar cell array and a hot spot resistant photovoltaic module to solve the problems existing in the prior art and improve the long-term power output reliability, durability and safety of photovoltaic modules.
[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0028] Example 1
[0029] This embodiment provides a heat-spot resistant solar cell array; please refer to [link to relevant documentation]. Figures 1-2The device includes a bypass component 14, at least one power generation unit 11, multiple conductive elements 12, and multiple positioning elements 13. The power generation unit 11 includes multiple battery strings 111 arranged side-by-side and connected in parallel along a first direction. Each battery string 111 includes multiple battery cells 112 connected in series along a second direction. Each power generation unit 11 has a busbar 113 at both ends along the second direction, and the battery cells 112 at both ends of each battery string 111 along the second direction are electrically connected to the corresponding busbar 113. The multiple conductive elements 12 are arranged parallel to each other along the second direction, and each conductive element 12 extends along the first direction. Each conductive element 12 can be attached to the back of at least one row of battery cells 112 of all battery strings 111 in the power generation unit 11; multiple positioning elements 13 are distributed in parallel along the first direction, each positioning element 13 extends along the second direction, and adjacent battery strings 111 in the power generation unit 11 are connected through a positioning element 13; a bypass component 14 is disposed on at least one side of the power generation unit 11 along the first direction, and the two ends of the bypass component 14 are electrically connected to the busbars 113 at both ends of the power generation unit 11, and the bypass component 14 can also be electrically connected to at least one conductive element 12.
[0030] Battery strings 111 are connected in parallel via busbars 113 to form power generation units 11. Bypass components 14 are connected in parallel between power generation units 11, and multiple battery strings 111 are bridging each other along a first direction (lateral) using conductive components 12, constructing a dual protection circuit. This improves the long-term power output reliability, durability, and safety of the photovoltaic module. When a power generation unit 11 is partially shaded, the conductive components 12 provide an alternative current path to prevent overheating in the shaded area. When a power generation unit 11 is severely shaded, the bypass components 14 maintain overall circuit continuity. Furthermore, the conductive components 12 are attached to the back of the cells 112 in the same row of battery strings 111, forming a surface-contact current collection network. This reduces losses by shortening the current transmission distance, thereby increasing the module's output power. Additionally, by connecting adjacent battery strings 111 using positioning components 13, the relative positions of the battery strings 111 are fixed, preventing displacement between battery strings 111 during lamination and improving the module's production yield. It should be noted that… Figure 1 and Figure 2 In the middle, the left and right directions, i.e., the horizontal direction, are the first direction, and the up and down directions, i.e., the vertical direction, are the second direction.
[0031] In the optional embodiments of this example, more preferably, each battery cell 112 is configured as a rectangular piece, the length direction of each battery cell 112 is parallel to the first direction, and the width direction of each battery cell 112 is parallel to the second direction; a main grid 1121 extending along the first direction is provided on the long side of the back side of the battery cell 112, and a plurality of sub-grids 1122 extending along the second direction are also provided parallel to the back side of the battery cell 112, and each sub-grid 1122 on the back side of the battery cell 112 is connected to the main grid 1121 on the back side of the battery cell 112; the conductive element 12 is electrically connected to each sub-grid 1122 on the back side of the corresponding battery cell 112.
[0032] The rectangular solar cells facilitate the improvement of utilization and the arrangement of the solar cell array. The electrical components 12 are electrically connected to the sub-grids 1122 on the back of the corresponding solar cell 112, which can form a surface contact current collection network. By shortening the current transmission distance, losses are reduced and the output power of the module is improved.
[0033] More preferably, the long sides of adjacent battery cells 112 in the battery string 111 overlap so that they can be connected in series for conductive connection.
[0034] In the optional embodiments of this example, more preferably, each conductive element 12 is configured as a conductive tape, which is attached to the back of the corresponding battery cell 112 and electrically connects each sub-grid 1122 on the back of the battery cell 112.
[0035] The width of each conductive tape does not exceed the width of a single solar cell 112. The conductive tape is arranged in a long strip shape, so that the long strip of conductive tape directly covers all the sub-grids 1122 on the back of the same row of solar cells 112 in the power generation unit 11, forming a surface contact current collection network. By shortening the current transmission distance, losses are reduced and the output power of the module is increased. At the same time, the number of connection points is reduced, eliminating the traditional precision welding steps and improving the module production efficiency. The flexible adhesion characteristics of the conductive tape avoid the silicon wafer microcracks caused by the high temperature and pressure of welding, further reducing the risk of mechanical damage to the solar cells and improving the yield of the photovoltaic module production process.
[0036] Further, please see Figure 2 Each solar cell 112 has a main grid 1121 with opposite electrical properties on the long side of its front and back surfaces. Several sub-grids 1122 are provided on the front and back surfaces respectively. The sub-grids 1122 are parallel to each other and converge at the main grid 1121.
[0037] In the optional scheme of this embodiment, more preferably, each positioning element 13 is set as a positioning tape, and each positioning tape is pasted between the back sides of two adjacent battery strings 111.
[0038] The positioning tape can directly bond and fix adjacent battery strings 111 in the power generation unit 11 from the back gap, mechanically fixing the relative position of the battery strings 111 and preventing the battery strings 111 from shifting during the lamination process; the length of the positioning tape is the same as the length of the battery strings 111.
[0039] In the optional embodiments of this example, it is more preferred that the positioning tape is the same color as the backing layer 3.
[0040] The positioning tape is the same color as the back panel layer 3. Each positioning tape is arranged to extend along the battery string 111 to fix the adjacent battery string 111, while making only the color of the back panel layer 3 material visible from the front, thus improving the overall aesthetics of the front.
[0041] In the optional embodiment, more preferably, the bypass component 14 includes a bypass conductor 141 and a plurality of bypass diodes 142. The bypass conductor 141 extends along a parallel second direction. Each bypass diode 142 is connected in series with the bypass conductor 141 and is electrically conductive. The two ends of the bypass conductor 141 are electrically conductive to the busbars 113 at both ends of the power generation unit 11. The bypass conductor 141 can also be electrically conductive to at least one conductive element 12. A bypass diode 142 is connected in series between adjacent conductive points on the bypass conductor 141.
[0042] In this configuration, each conductive tape is arranged to extend along different rows of battery cells 112 within the power generation unit 11, perpendicular to the positioning tape of each column. The conductive tape vertically divides the parallel battery strings 111 within the power generation unit 11 into multiple unit blocks along the second direction (longitudinal direction). A bypass conductor 141 is disposed on one side of the power generation unit 11 along the first direction and extends parallel to the second direction. The part of the bypass conductor 141 that is electrically connected to the conductive element 12 is an electrical conduction point. The two ends of the bypass conductor 141 along the second direction (longitudinal direction) are electrically connected to the busbars 113 at both ends of the power generation unit 11. The part of the bypass conductor 141 that is electrically connected to the busbar 113 is also an electrical conduction point. Therefore, a bypass diode 142 is connected in series between adjacent electrical conduction points, so that the bypass diode 142 is connected in parallel with the power generation unit 11 or multiple unit blocks inside the power generation unit 11 through the bypass conductor 141. When the power generation unit 11 is severely blocked, the bypass diode 142 can maintain the overall circuit conduction.
[0043] In the optional scheme of this embodiment, it is more preferred that the bypass conductor 141 is electrically connected to each conductive element 12.
[0044] Each unit block is connected in parallel with a bypass diode 142, which further enhances the ability to maintain the overall circuit conduction.
[0045] In the optional scheme of this embodiment, it is more preferred that the number of power generation units 11 is set to multiple, the power generation units 11 are distributed in parallel along the first direction (lateral direction), and each power generation unit 11 is provided with a busbar 113, a bypass component 14, multiple conductive components 12 and multiple positioning components 13; the busbar 113 on one side of an adjacent power generation unit 11 can be electrically conductive so that multiple power generation units 11 are connected in series.
[0046] In this configuration, the busbars 113 on the same side of adjacent power generation units 11 can be connected, while the busbars 113 on the other side can be disconnected, thus achieving series connection between adjacent power generation units 11. Furthermore, the busbars 113, bypass components 14, multiple conductive elements 12, and multiple positioning elements 13 of each power generation unit 11 are arranged in the same manner, as described above. Figure 1 I won't go into too much detail here.
[0047] In addition, the two ends of the multiple power generation units 11 connected in series are respectively connected to a positive lead conductor and a negative lead conductor. The positive lead conductor is electrically connected to the positive bus bar of the battery cell array to output the positive power of the battery cell array, and the negative lead conductor is electrically connected to the negative bus bar of the battery cell array to output the negative power of the battery cell array.
[0048] Example 2
[0049] This embodiment provides a photovoltaic module resistant to hot spots. Please refer to [link / reference]. Figure 3 It includes a panel layer 2, a back sheet layer 3, and an anti-hot spot solar cell array 1 as in Embodiment 1; the panel layer 2 is fixedly disposed on the front side of the anti-hot spot solar cell array 1; and the back sheet layer 3 is fixedly disposed on the back side of the anti-hot spot solar cell array 1.
[0050] Among them, the anti-hot spot solar cell array 1 is encapsulated and protected by the panel layer 2 and the backsheet layer 3. In conjunction with the anti-hot spot solar cell array 1, the reliability, durability and safety of the photovoltaic module can be further improved.
[0051] In an optional embodiment, both the panel layer 2 and the backsheet layer 3 are connected to the anti-hot spot solar cell array 1 through the encapsulation layer 4, and both the panel layer 2 and the encapsulation layer 4 are made of transparent insulating material.
[0052] Specifically, panel layer 2 is a transparent film made of ETFE (ethylene-tetrafluoroethylene copolymer) with a thickness of 0.02-0.3mm. The use of an ultra-thin transparent film panel reduces the weight of the component. Encapsulation layer 4 is a transparent film made of EVA (ethylene-vinyl acetate copolymer) with a thickness of 0.2-0.5mm, used to achieve interlayer bonding and fuse the materials of each layer into an integral structure. Backsheet layer 3 is a white or black sheet made of PET (polyethylene terephthalate) with a thickness of 0.02-0.3mm, providing insulation and weather protection.
[0053] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.
Claims
1. A hot spot resistant solar cell array, characterized in that: include: At least one power generation unit (11) is provided, the power generation unit (11) includes a plurality of battery strings (111) arranged side by side and connected in parallel along a first direction, each battery string (111) includes a plurality of battery cells (112) connected in series along a second direction; the power generation unit (11) is provided with a busbar (113) at both ends along the second direction, and the battery cells (112) at both ends of each battery string (111) along the second direction are electrically connected to the corresponding busbar (113); Multiple conductive elements (12) are distributed in parallel along the second direction, each conductive element (12) extends along the first direction, and each conductive element (12) can be attached to and electrically connected to the back of at least one row of battery cells (112) on all the battery strings (111) of the power generation unit (11). Multiple positioning elements (13) are provided, the multiple positioning elements (13) are distributed in parallel along the first direction, each positioning element (13) extends along the second direction, and adjacent battery strings (111) within the power generation unit (11) are connected through one of the positioning elements (13); and A bypass component (14) is disposed on at least one side of the power generation unit (11) along the first direction. The two ends of the bypass component (14) are electrically connected to the busbars (113) at both ends of the power generation unit (11), and the bypass component (14) is also electrically connected to at least one of the conductive elements (12).
2. The anti-hot spot solar cell array according to claim 1, characterized in that: Each of the battery cells (112) is configured as a rectangular piece, with the length direction of each battery cell (112) parallel to the first direction and the width direction of each battery cell (112) parallel to the second direction; a main grid (1121) extending along the first direction is provided on the long side of the back of the battery cell (112), and a plurality of sub-grids (1122) extending along the second direction are also provided parallel to the back of the battery cell (112), and each of the sub-grids (1122) on the back of the battery cell (112) is connected to the main grid (1121) on the back of the battery cell (112); the conductive element (12) is electrically connected to each of the sub-grids (1122) on the back of the corresponding battery cell (112).
3. The anti-hot spot solar cell array according to claim 2, characterized in that: Each of the conductive components (12) is configured as a conductive tape, which is attached to the back of the corresponding battery cell (112) and electrically conducts to each of the sub-grids (1122) on the back of the corresponding battery cell (112).
4. The anti-hot spot solar cell array according to claim 1, characterized in that: Each of the positioning components (13) is configured as a positioning tape, and each positioning tape is pasted between the back sides of two adjacent battery strings (111).
5. The anti-hot spot solar cell array according to claim 4, characterized in that: The positioning tape is used to match the color of the backing layer (3).
6. The anti-hot spot solar cell array according to claim 1, characterized in that: The bypass assembly (14) includes a bypass conductor (141) and a plurality of bypass diodes (142). The bypass conductor (141) extends parallel to the second direction. Each of the bypass diodes (142) is connected in series with the bypass conductor (141) and is electrically connected. The two ends of the bypass conductor (141) are electrically connected to the busbars (113) at both ends of the power generation unit (11). The bypass conductor (141) is also electrically connected to at least one of the conductive elements (12). A bypass diode (142) is connected in series between adjacent electrical connection points on the bypass conductor (141).
7. The anti-hot spot solar cell array according to claim 6, characterized in that: The bypass conductor (141) is electrically connected to each of the conductive elements (12).
8. The anti-hot spot solar cell array according to claim 2, characterized in that: The long sides of adjacent battery cells (112) in the battery string (111) overlap to enable them to be connected in series for conductive connection.
9. The anti-hot spot solar cell array according to any one of claims 1-8, characterized in that: The number of power generation units (11) is set to multiple, and the multiple power generation units (11) are distributed in parallel along the first direction. Each power generation unit (11) is provided with the busbar (113), the bypass component (14), multiple conductive components (12) and multiple positioning components (13). The busbar (113) on the side of the adjacent power generation unit (11) can be electrically connected so that the multiple power generation units (11) are connected in series.
10. A photovoltaic module resistant to hot spots, characterized in that: include: The anti-spot solar cell array (1) as described in any one of claims 1-9; The panel layer (2) is fixedly disposed on the front side of the anti-spot solar cell array (1); The backsheet layer (3) is fixedly disposed on the back side of the anti-spot solar cell array (1); The encapsulation layer (4) is used to connect the panel layer (2) and the backsheet layer (3) to the anti-spot solar cell array (1), and the panel layer (2) and the encapsulation layer (4) are both made of transparent insulating material.