Crystalline silicon battery modules and solar photovoltaic panels

Abstract

The present invention provides a crystalline silicon cell assembly and a solar photovoltaic cell panel. The crystalline silicon cell assembly comprises: two symmetrically parallel connected cell arrays, each cell array comprises at least two cell strings, each cell string comprises a plurality of sliced ​​cells connected in series, the sliced ​​cells are 1 / 3 cell slices obtained by cutting a photovoltaic cell sheet, in each cell array, two adjacent cell strings have opposite polarities on the same side and are connected in series with each other, and the lead-out end of the crystalline silicon cell assembly is located in the middle of the cell assembly.

Description

Technical Field

[0001] The invention relates to the field of solar photovoltaics, and in particular to a crystalline silicon cell assembly and a solar photovoltaic cell panel. Background Art

[0002] With the development of high-efficiency batteries, the size of batteries has gradually increased. Currently, large-size batteries such as 158.75, 161.75, 166, and 210mm have been gradually developed from 156mm. As the size of batteries increases, the Is short-circuit current of battery cells and modules continues to increase. In order to reduce Rs (series resistance), most batteries are currently cut in half (1 / 2 slices) to produce half-piece modules. By cutting the battery in half (1 / 2 slices), Isc and Rs are reduced, but the current increases due to the increase in battery size. Even after slicing, the Isc of the module will still increase because the circuit is eventually connected in parallel, which ultimately affects the matching of the system installation.

[0003] Taking 210mm battery as an example, the current of a single battery is 18A, far exceeding the 10-12A level of existing batteries. Producing this type of battery module based on the current version will have a huge impact on the system and raw material manufacturers. At the same time, excessive current will make the hot spot effect of the module more obvious, affecting the service life of the module. Summary of the invention

[0004] In order to solve the above technical problems, the present invention discloses a crystalline silicon battery module, which includes: two battery arrays connected in parallel symmetrically, each battery array includes at least two battery strings, each battery string includes a plurality of sliced ​​batteries connected in series, the sliced ​​battery is a 1 / 3 battery slice obtained by cutting a photovoltaic battery sheet, in each battery array, the same sides of two adjacent battery strings have opposite polarities and are connected in series with each other, and the lead-out end of the crystalline silicon battery module is located in the middle of the battery module.

[0005] By cutting large-size batteries into 1 / 3 pieces, the current of a single cell after slicing is 1 / 3 of the full cell. After the above optimized layout design, the final output current of the module is 2 / 3 of the full cell, thereby solving the problem of excessive current of large-size batteries and making the final voltage and current of the module basically consistent with the current conventional module parameters; at the same time, the reduction in current can correspondingly reduce the occurrence of abnormal problems such as hot spots. In addition, compared with cutting in half, the size of a single cell is smaller when the same-size battery is cut into three pieces, and the ability to resist hidden cracks is enhanced after being made into a module, which can effectively improve the load capacity of the module.

[0006] Furthermore, a corresponding number of bypass diodes are provided in the middle of the battery assembly to protect the circuit.

[0007] By adopting the above solution, a corresponding number of bypass diodes are provided to protect the circuit.

[0008] Furthermore, each battery array includes at least three odd-numbered battery strings, and the positive electrodes of the two battery arrays are introduced into the middle of the battery assembly through lead-out welding strips.

[0009] The above solution is adopted to achieve optimized design and layout under odd number of battery strings.

[0010] Furthermore, the lead-out welding strip is located inside the battery array.

[0011] By adopting the above scheme, the component area can be reduced and the component efficiency can be improved.

[0012] Furthermore, a busbar used as a positive electrode lead-out terminal is provided in the middle of the battery assembly, and the busbar is overlap-welded with the lead-out welding strip.

[0013] The above solution is adopted to realize the positive electrode lead-out terminal of the battery assembly.

[0014] Furthermore, the lead-out welding strip is welded to the busbar welding strip at 90°.

[0015] The above solution reduces the difficulty of welding connection operation and has a simpler structure.

[0016] Furthermore, an insulating strip is provided under the lead-out welding strip to avoid contact with the battery cell.

[0017] The above solution is adopted to avoid leakage or short circuit caused by contact between the welding ribbon and the battery cell.

[0018] Furthermore, the insulating strip completely covers the lead-out welding strip in the length direction, and the insulating strip meets the standard creepage distance requirement in the width direction.

[0019] The above solution is adopted to ensure the insulation between the welding strip and the battery cell.

[0020] Furthermore, a first bus bar and a second bus bar for overlapping two battery strings are provided in the middle of the battery assembly, and the first bus bar and the second bus bar are overlap-welded to each other, wherein the unwelded portions of the first bus bar and the second bus bar serve as one end of the lead wire.

[0021] The above solution reduces the difficulty of welding connection operation and has a simpler structure.

[0022] The technical solution of the present invention also provides a solar photovoltaic cell panel, which includes the crystalline silicon cell assembly as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a layout diagram of a battery assembly according to an embodiment of the present invention;

[0024] Figure 2is a circuit diagram of a battery assembly according to an embodiment of the present invention;

[0025] Figure 3 is a layout diagram of a battery assembly according to another embodiment of the present invention;

[0026] Figure 4 is a circuit diagram of a battery assembly according to another embodiment of the present invention;

[0027] Figure 5 is a layout diagram of a battery assembly of a preferred embodiment of the present invention;

[0028] Figure 6 is a circuit diagram of a battery assembly of a preferred embodiment of the present invention;

[0029] Figure 7 is a circuit diagram of a battery assembly of an alternative embodiment of the present invention;

[0030] Fig. 8A Shows Figure 5 A partial enlarged view of the portion shown in A;

[0031] Figure 8B Shows Figure 5 Schematic diagram of the welding strips led out from both ends a and b;

[0032] Figure 8C Shows Fig. 8A Top view of Figures 1 and 2;

[0033] Fig.8D Shows Fig. 8A Side view of 1 and 2;

[0034] Fig. 8E Shows Figure 5 The overall schematic diagram of part A after welding the welding strip. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described below in conjunction with specific embodiments, but the present invention is not limited to these embodiments.

[0036] The present invention discloses a crystalline silicon battery module, which comprises: two battery arrays connected in parallel symmetrically, each battery array comprises at least two battery strings, each battery string comprises a plurality of sliced ​​batteries connected in series, the sliced ​​batteries are 1 / 3 battery slices obtained by cutting a photovoltaic battery sheet, in each battery array, the same sides of two adjacent battery strings have opposite polarities and are connected in series with each other, and the lead-out end of the crystalline silicon battery module is located in the middle of the battery module.

[0037] By cutting large-size batteries into 1 / 3 pieces, the current of a single cell after slicing is 1 / 3 of the full cell. After the above optimized layout design, the final output current of the module is 2 / 3 of the full cell, thereby solving the problem of excessive current of large-size batteries and making the final voltage and current of the module basically consistent with the current conventional module parameters; at the same time, the reduction in current can correspondingly reduce the occurrence of abnormal problems such as hot spots. In addition, compared with cutting in half, the size of a single cell is smaller when the same-size battery is cut into three pieces, and the ability to resist hidden cracks is enhanced after being made into a module, which can effectively improve the load capacity of the module.

[0038] Furthermore, a corresponding number of bypass diodes are provided in the middle of the battery assembly to protect the circuit.

[0039] With the above solution, a bypass diode is provided to protect the circuit.

[0040] Furthermore, each battery array includes at least three odd-numbered battery strings, and the positive electrodes of the two battery arrays are introduced into the middle of the battery assembly through lead-out welding strips.

[0041] The above solution is adopted to achieve optimized design and layout under odd number of battery strings.

[0042] Furthermore, the lead-out welding strip is located inside the battery array.

[0043] By adopting the above scheme, the component area can be reduced and the component efficiency can be improved.

[0044] Furthermore, a busbar used as a positive electrode lead-out terminal is provided in the middle of the battery assembly, and the busbar is overlap-welded with the lead-out welding strip.

[0045] The above solution is adopted to realize the positive electrode lead-out terminal of the battery assembly.

[0046] Furthermore, the lead-out welding strip is welded to the busbar welding strip at 90°.

[0047] The above solution reduces the difficulty of welding connection operation and has a simpler structure.

[0048] Furthermore, an insulating strip is provided under the lead-out welding strip to avoid contact with the battery cell.

[0049] The above solution is adopted to avoid leakage or short circuit caused by contact between the welding ribbon and the battery cell.

[0050] Furthermore, the insulating strip completely covers the lead-out welding strip in the length direction, and the insulating strip meets the standard creepage distance requirement in the width direction.

[0051] The above solution is adopted to ensure the insulation between the welding strip and the battery cell.

[0052] Furthermore, a first bus bar and a second bus bar for overlapping two battery strings are provided in the middle of the battery assembly, and the first bus bar and the second bus bar are overlap-welded to each other, wherein the unwelded portions of the first bus bar and the second bus bar serve as one end of the lead wire.

[0053] The above solution reduces the difficulty of welding connection operation and has a simpler structure.

[0054] The technical solution of the present invention also provides a solar photovoltaic cell panel, which includes the crystalline silicon cell assembly as described above.

[0055] See also Figure 1 and Figure 2 , which shows a layout diagram and a corresponding circuit diagram of a battery assembly according to an embodiment of the present invention. In this embodiment, the battery assembly includes two battery arrays connected in parallel symmetrically, each battery array includes 6 battery strings, each battery string includes a plurality of sliced ​​batteries connected in series, and the sliced ​​batteries are 1 / 3 battery slices obtained by cutting a photovoltaic battery sheet. In each battery array, the same side of two adjacent battery strings have opposite polarities and are connected in series with each other, and the lead-out end of the crystalline silicon battery assembly is located in the middle of the battery assembly.

[0056] Preferably, a corresponding number of bypass diodes are arranged in the middle of the battery assembly, such as Figure 2 As shown in the embodiment of FIG. 1 , the lead end of the component is located in the middle of the component, and a total of 3 diodes are matched. The circuit is protected by arranging a corresponding number of diodes in the middle of the component.

[0057] Although in Figure 1 and Figure 2 In the embodiment, each battery array includes 6 battery strings, but it can be understood that the number of battery strings is not limited thereto, and the specific number depends on the size requirements of the battery assembly, etc.

[0058] In the above embodiment, the circuit diagram adopts the module design of three-slice batteries in an even number of strings, the module lead-out terminal is located in the middle of the module, and a total of 3 diodes are matched. Figure 3 and Figure 4, which shows the layout diagram and corresponding circuit diagram of a battery assembly according to another embodiment of the present invention. In this embodiment, the battery assembly includes two battery arrays connected in parallel symmetrically, each battery array includes 5 battery strings, each battery string includes a plurality of sliced ​​batteries connected in series, and the sliced ​​battery is a 1 / 3 battery slice obtained by cutting a photovoltaic battery sheet. In each battery array, the same side of two adjacent battery strings have opposite polarities and are connected in series with each other. Since the number of battery strings in each battery array is an odd number, in order to make the lead-out end of the crystalline silicon battery assembly located in the middle of the battery assembly, the positive electrodes of the two battery arrays are introduced into the middle of the battery assembly through the lead-out welding tape. In this embodiment, on the outside of the battery array, the positive electrodes at both ends of the battery string are introduced into the middle of the assembly by using welding tape 7 at both ends of the assembly.

[0059] In a preferred embodiment, see Figure 5-Figure 6 , the lead-out welding strip 7 is located inside the battery array. Since the lead-out welding strip 7 is located inside the battery array, the assembly area is reduced under the condition of the same power, and the assembly efficiency is improved (=assembly power / assembly area).

[0060] See also Figure 7 , which shows an alternative embodiment of the circuit design when the battery string is an odd number of strings.

[0061] Although the two battery arrays shown in the above embodiments are symmetrically distributed in the horizontal direction, the battery strings in each battery array are arranged vertically in sequence, that is, the above embodiments are all battery cell layouts of a horizontal structure, but it is obviously understandable that the battery cell layout can also be a vertical structure, that is, the two battery arrays are symmetrically distributed in the vertical direction, and the battery strings in each battery array are arranged horizontally in sequence.

[0062] See also Figure 8A-8E ,in, Fig. 8A Shows Figure 5 A partial enlarged view of the part shown in A. Figure 8B Shows Figure 5 Schematic diagram of the welding strip introduced from both ends a and b. Figure 8C Shows Fig. 8A The top view of Figures 1 and 2. Fig.8D Shows Fig. 8A Side view of Figures 1 and 2. Fig. 8E Shows Figure 5 The overall schematic diagram of part A after welding the welding strip.

[0063] For the above-mentioned figures, 1 is busbar 1; 2 is busbar 2; 3 is the common welding part of busbars 1 and 2; 4 is the unwelded part of busbar 1, which serves as the negative lead-out terminal; 5 is a welding strip, which overlaps with the welding strip 7 introduced at ends a and b, serving as the positive lead-out terminal; 6 is an insulating strip, which is used to isolate the welding strip 7 from the battery cell to avoid leakage or short circuit; 7 is a layout Figure 2 The welding strip connected from end a to end b overlaps with 5; 8 is the common welding part of welding strips 5 and 7.

[0064] The specific plan is:

[0065] For regular odd-numbered string components, Figure 5 The A part shown should be a complete welding strip. This solution realizes the connection between the negative electrode of the battery and the positive electrode led out from the a and b ends by dividing the welding strip into two.

[0066] like Fig. 8A As shown, parts 1 and 2 are two separate welding strips. Figure 8C and Fig.8D The lap welding is realized in the form of, wherein 3 is the connecting part between the two welding strips to be welded, 4 is the reserved part of the welding strip 1 that does not need to be welded, and 4 will serve as one end of the lead wire.

[0067] like Figure 8B As shown, 7 is S layout Figure 2 The welding strips connecting the two ends of a and b are used as carriers of the electrodes at both ends. The welding strips 5 and 7 are welded at 90 degrees. Fig. 8E As shown, 8 is the overlap welding position of the welding strips 5 and 7.

[0068] In order to avoid leakage or short circuit caused by contact between the welding ribbon and the battery cell, an insulating strip 6 needs to be added under the welding ribbon 7. The specific implementation of the insulating strip 6 includes but is not limited to a single-layer EPE, EVA+EPE (or insulating backplane) or POE+EPE (or insulating backplane). The insulating strip needs to completely cover the welding ribbon 7 in the length direction, and reserve a creepage distance that meets the standard requirements in the width direction.

[0069] like Fig. 8E The figure shows the schematic diagram of the lead-out part in the middle of the component after completion, where parts 4 and 5 are the lead-out ends. After the welding ribbons are overlapped, they are folded upwards and serve as the positive and negative electrodes of the component respectively.

[0070] The above part is Figure 6 The specific embodiment of the circuit diagram shown in FIG. Figure 7 The circuit diagram shown is a reverse connection. The difference is that when the welding ribbons 1 and 2 are welded, the welding ribbon 2 is located above 1, and the welding ribbon 2 has a reserved bending part. The other operations are the same.

[0071] Technical effects brought about by the technical solution of the present invention

[0072] For battery cells with specifications of 210 and above, the current of a single cell can reach more than 18A. If conventional welding solutions are used, the current of the assembly will also exceed 18A, which is much higher than the current level of 10-12A of conventional assemblies, and has a significant impact on the installation end of the system. The solution of the present invention is to cut the whole cell into three pieces, that is, the size of a single piece is 210*70mm, and the current of the small piece of battery is 1 / 3 of the current of the whole cell. By performing series and parallel layout according to the above design scheme, the final assembly output current can be 12A, which is basically the same as conventional assemblies;

[0073] After cutting into three pieces, the gaps between cells and cell strings are denser than those of conventional modules, which can increase the light reflection area of ​​the module backplane, thereby improving the utilization rate of light and increasing power.

[0074] After being cut into three pieces, the area of ​​a single battery cell is smaller, the load resistance capacity is improved, and the ability to resist hidden cracks is effectively enhanced.

[0075] The above is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several modifications and improvements without departing from the inventive concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A crystalline silicon battery assembly, characterized in that: include: Two battery arrays are symmetrically connected in parallel, each battery array includes at least two battery strings, each battery string includes a plurality of sliced ​​batteries connected in series, the sliced ​​battery is a 1 / 3 battery slice obtained by cutting a photovoltaic battery sheet, in each battery array, the same side of two adjacent battery strings have opposite polarities and are connected in series with each other, and the lead-out end of the crystalline silicon battery assembly is located in the middle of the battery assembly; wherein, A first bus bar and a second bus bar are provided in the middle of the battery assembly for overlapping two battery strings. The first bus bar and the second bus bar are overlapped and welded to each other, wherein the unwelded portion of the first bus bar and the second bus bar serves as one end of the lead wire; wherein, The positive electrodes of the two battery arrays are led out to the middle of the battery assembly through lead-out welding strips, and an insulating strip is arranged under the lead-out welding strip to avoid contact with the battery cell; the length direction of the insulating strip completely covers the lead-out welding strip, and the width direction of the insulating strip meets the standard creepage distance requirements.

2. The crystalline silicon battery assembly according to claim 1, characterized in that: In the middle of the battery assembly, there are a corresponding number of bypass diodes to protect the circuit.

3. The crystalline silicon battery assembly according to claim 2, characterized in that: Each battery array includes at least three odd-numbered battery strings.

4. The crystalline silicon battery assembly according to claim 3, characterized in that: The lead-out welding strip is located inside the battery array.

5. The crystalline silicon battery assembly according to claim 4, characterized in that: A busbar used as a positive electrode lead-out terminal is provided in the middle of the battery assembly, and the busbar is overlap-welded with the lead-out welding strip.

6. The crystalline silicon battery assembly according to claim 5, characterized in that: The lead-out welding strip is welded to the busbar welding strip at 90°.

7. A solar photovoltaic panel, characterized in that: Comprising a crystalline silicon battery assembly as described in any one of claims 1-6.

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