Battery piece, battery string, photovoltaic module and electric device thereof

Abstract

The utility model relates to the technical field of photovoltaic power generation, in particular to a battery piece, a battery string, a photovoltaic module and an electric device thereof, and the battery piece comprises a battery piece body, an auxiliary grid line, a main grid line and a bonding pad. The battery piece body is used for photovoltaic power generation and is provided with a functional end face; the auxiliary grid lines are arranged on the functional end face in the first direction and used for collecting current on the battery piece. The main grid lines are arranged on the function end face in the second direction, and the main grid lines are used for collecting current on the auxiliary grid lines; the bonding pad comprises a base part and a protruding part, the base part is fixedly arranged at the intersection point of the main grid line and the auxiliary grid line, the protruding part is fixedly arranged on the base part, and the thickness of the protruding part is smaller than that of the base part. According to the battery piece provided by the invention, the arranged protruding part not only keeps the original height of the bonding pad, but also can conduct current, and the thickness of the protruding part is smaller than that of the base part, so that the overall size of the bonding pad is reduced, the material consumption of the bonding pad is reduced, and the material cost of the bonding pad is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of photovoltaic power generation, in particular to a cell piece, a cell string, a photovoltaic module and an electric device thereof. BACKGROUND

[0002] In the current preparation of photovoltaic cell pieces, the proportion of silver paste in the cost of photovoltaic cells is about 35%, which is the second largest cost next to the silicon wafer. Silver paste plays a key role in the process of manufacturing photovoltaic cells, especially in forming electrodes and charge transport. It is the material with the highest proportion in the non-silicon cost of the cell link, accounting for about 35% of the overall cost. The main components of silver paste include high-purity silver powder, glass system and organic carrier, among which the proportion of silver powder is large, about 90%.

[0003] The conventional electrode cost reduction of cell pieces is mainly through the following three ways:

[0004] (1) Reducing the thickness of the electrode to reduce the amount of silver paste, but this method is easy to form empty welding, mainly because the height of the solder pad is lower than the fine grid, the solder strip is easy to hang and not connected, the greater the height difference between the solder pad and the fine grid, the more difficult it is to weld.

[0005] (2) Reducing the area of the electrode to reduce the amount of silver paste, but this method will cause insufficient adhesion of silver paste to the silicon wafer.

[0006] (3) Reducing the amount of silver paste by doping base metals, but this method will cause changes in the physical properties of the electrode, and there is no reliable material to replace it at present. CONTENT OF THE UTILITY MODEL

[0007] The purpose of the present application is to provide a cell piece, a cell string, a photovoltaic module and an electric device thereof, which can reduce the manufacturing cost while ensuring the quality of electrical connection.

[0008] In order to achieve the above-mentioned purpose, in a first aspect, an embodiment of the present application provides a cell piece, comprising a cell piece body, a sub-grid line, a main grid line and a solder pad. The cell piece body is used for photovoltaic power generation, and has a functional end face; the sub-grid line is arranged on the functional end face along a first direction for collecting current on the cell piece; the main grid line is arranged on the functional end face along a second direction, and the main grid line and the sub-grid line are arranged in a cross manner, and the main grid line is used for collecting current on the sub-grid line; the solder pad comprises a base part and a protruding part, the base part is fixedly arranged at the intersection of the main grid line and the sub-grid line, and the protruding part is fixedly arranged on the base part, and the thickness of the protruding part is less than the thickness of the base part.

[0009] In one embodiment, the first direction and the second direction have an included angle a, wherein 0° < a ≤ 90°.

[0010] In one embodiment, the thickness of the protruding part is H, the thickness of the base part is K, and the number of the protruding parts arranged on the base part is N, wherein N*H<K, 1≤N, and N is an integer.

[0011] In one embodiment, when the number of the protruding parts is more than two, the protruding parts are arranged at intervals.

[0012] In one embodiment, the height of the protruding part is E, the height of the base part is F, and the height of the sub-grid line is L, wherein 4μm≤E+F≤L.

[0013] In one embodiment, 5μm≤L≤12μm.

[0014] In the second aspect, the embodiments of the present application further provide a battery string, comprising a battery piece body, and the number of the battery piece bodies is at least two, and at least two battery piece bodies are electrically connected.

[0015] In one embodiment, the battery string further comprises a solder strip, the solder strip is electrically connected with the solder pad through which the solder strip passes, and the solder strip is connected in series with every two adjacent battery pieces.

[0016] In the third aspect, the embodiments of the present application further provide a photovoltaic module, comprising the battery string of any of the above embodiments.

[0017] In the fourth aspect, the embodiments of the present application further provide an electric device, comprising the photovoltaic module of any of the above embodiments.

[0018] The battery piece provided by the present application has the protruding part arranged thereon, which not only maintains the original height of the solder pad, but also enables the current to pass through, and the thickness of the protruding part is less than the thickness of the base part, thereby reducing the overall volume of the solder pad and the material of the solder pad, and reducing the material cost of the solder pad.

[0019] Other features and advantages of the present application will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0021] Figure 1 Structure diagram of one embodiment of the battery piece provided by the present application from one perspective;

[0022] Figure 2A two-view structural schematic diagram of one of the embodiments of the battery piece provided in the present application is shown in the following figure:

[0023] Figure 3 A three-view structural schematic diagram of one of the embodiments of the battery piece provided in the present application is shown in the following figure:

[0024] Figure 4 A four-view structural schematic diagram of one of the embodiments of the battery piece provided in the present application is shown in the following figure:

[0025] Figure 5 A five-view structural schematic diagram of one of the embodiments of the battery piece provided in the present application is shown in the following figure.

[0026] Icon:

[0027] 100-battery piece body; 200-substrate grid line; 300-welding pad; 310-base part; 320-protruding part; 400-welding strip. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, but not all the embodiments. The components of the embodiments of the present application described and shown in the drawings can be arranged and designed in various different configurations.

[0029] In the description of the present application, it should be noted that the directions or position relationships indicated by the terms “inner”, “outer” and the like are based on the directions or position relationships shown in the drawings, or the directions or position relationships in which the products of the present application are usually placed, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms “first”, “second” and the like are only used for differentiation and description, and cannot be understood as indicating or implying relative importance.

[0030] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms “set”, “connected” should be understood broadly, for example, can be fixedly connected, or can be detachably connected, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0031] In a first aspect, the embodiments of the present application provide a battery piece, such as Figure 1As shown, the cell includes a cell body 100, a sub-grid line 200, a main grid line and a solder pad 300.

[0032] The cell body 100 is used for photovoltaic power generation, and the cell body 100 has a functional end face. Exemplarily, the functional end face is an end face for receiving solar radiation, but in other embodiments, the functional end face is the opposite of the end face for receiving solar radiation.

[0033] The sub-grid line 200 is arranged on the functional end face in a first direction for collecting current on the cell.

[0034] The main grid line is arranged on the functional end face in a second direction, so that the main grid line is arranged crossing the sub-grid line 200, and the main grid line is used for collecting current on the sub-grid line 200. The current on the cell can be effectively collected and transmitted. The sub-grid line 200 is responsible for collecting current in each region of the cell, and the main grid line collects and transmits these currents to the solder pad 300.

[0035] Exemplarily, the solder pad 300 is used to collect current on the main grid line, and at least one solder pad 300 is arranged on the main grid line. The solder pads 300 on the same main grid line and the solder pads 300 on different main grid lines are electrically connected by a conductor. The solder pad 300 guides the current on the main grid line to the conductor, and the conductor collects the current on the solder pad 300 and transmits it to the outside. Exemplarily, the conductor is, for example, a solder strip 400.

[0036] The solder pad 300 includes a base portion 310 and a protruding portion 320. The base portion 310 is fixedly arranged at the intersection of the main grid line and the sub-grid line 200, which ensures the stable connection of the solder pad 300 with the cell body 100. Exemplarily, the solder pad 300 is made of silver, but it can also be made of other conductive materials, such as gold, copper or aluminum, etc.

[0037] The protruding portion 320 is fixedly arranged on the base portion 310, and the thickness of the protruding portion 320 is less than the thickness of the base portion 310. The protruding portion 320 is electrically connected to the conductor. The current on the main grid line is conducted to the base portion 310, and then from the base portion 310 to the protruding portion 320, and then from the protruding portion 320 to the conductor.

[0038] The protruding portion 320 is arranged to maintain the original height of the solder pad 300, maintain good electrical connection between the solder pad 300 and the conductor, and reduce the overall volume and material of the solder pad 300 by reducing its thickness. This design not only ensures the smooth transmission of current, but also reduces material costs. Since the thickness of the protruding portion 320 is less than that of the base portion 310, the overall volume of the solder pad 300 is correspondingly reduced, thereby reducing the material of the solder pad 300. In the case of large-scale production of cells, this reduction in material cost is of great significance to improve the market competitiveness of the product.

[0039] In one embodiment, the first direction and the second direction have an angle α, where 0°<α≤90°. Exemplarily, the angle α between the first direction and the second direction is 90°. In another embodiment, the angle α between the first direction and the second direction is 60°. In another embodiment, the angle α between the first direction and the second direction is 45°. In another embodiment, the angle α between the first direction and the second direction is 30°. In another embodiment, the angle α between the first direction and the second direction is 20°. In another embodiment, the angle α between the first direction and the second direction is 5°.

[0040] When the cell is rectangular, α is set to 90°. When the cell is diamond-shaped, α is set to 45°. When the angle α is appropriate, the secondary grid lines 200 can more evenly cover the cell surface, optimizing the current collection path on the cell. This allows for more efficient collection of the current generated by the photovoltaic effect. By selecting the appropriate angle α, the resistance loss during current transmission can be minimized, thereby improving the overall efficiency of the cell.

[0041] like Figure 1 As shown, in one embodiment, the thickness of the protrusion 320 is H, the thickness of the base 310 is K, and the number of the protrusions 320 arranged on the base 310 is N, wherein N*H<K, 1≤N, and N is an integer.

[0042] For example, Figure 1 As shown, N=3, there is a gap between the three protrusions 320. In another embodiment, as shown in FIG. Figure 2 As shown, N=3, and between the three protrusions 320, two protrusions 320 are arranged in close contact and spaced apart from another protrusion 320. Figure 3 As shown, in another embodiment, N=2. Figure 4 As shown, in another embodiment, N=1, and the protrusion 320 is provided in the middle of the base portion 310. Of course, in another embodiment, N may also be equal to 4, 5, 6, etc.

[0043] N*H<K, making the overall thickness of the raised portion 320 smaller than the thickness of the base portion 310, can reduce the volume and material consumption of the pad 300 to a certain extent. This reduction in material consumption directly reduces the cost of the pad 300, thereby controlling overall production costs. The provision of the raised portion 320 may help improve the contact area and contact quality between the pad 300 and the connecting component, thereby enhancing the stability and reliability of the connection.

[0044] like Figure 1 and Figure 3 As shown, in one embodiment, when two or more protrusions 320 are provided, the protrusions 320 are arranged at intervals.

[0045] like Figure 1 As shown, in one embodiment, the height of the protrusion 320 is E, the height of the base portion 310 is F, and the height of the secondary gate line 200 is L, wherein 4 μm≤E+F≤L.

[0046] E+F≤L makes the height of the secondary gate line 200 greater than the total height of the pad 300, and the secondary gate line 200 can protect the pad 300 from damage such as bumps. In practical applications, this helps to extend the service life of the pad 300 and improve the reliability and stability of the device.

[0047] 4μm≤E+F, prevents the height of the pad 300 from being too low and causing poor contact with the conductor. Poor contact may cause problems such as poor current transmission, increased resistance, and heat generation, thereby affecting the overall performance of the device. By setting a reasonable lower limit for the height of the pad 300, these potential problems can be effectively avoided. Under the premise of ensuring good contact between the pad 300 and the conductor, the overall height of the pad 300 can be reduced by controlling the total height (E+F) of the pad 300 not to exceed the height L of the secondary grid line 200. This helps to reduce the amount of material used in the pad 300 and reduce production costs. At the same time, the reduction in the height of the pad 300 also helps to improve the compactness and integration of the device, providing strong support for the miniaturization and lightweight design of the device.

[0048] In one embodiment, 5μm≤L≤12μm. As one of the channels for current transmission, the reasonable setting of the height of the auxiliary grid line 200 is crucial to ensure the smooth transmission of current. Setting L within the range of 5μm to 12μm can effectively balance the efficiency and stability of current transmission, avoiding performance and cost issues caused by excessive or insufficient current. The height setting of the auxiliary grid line 200 will also affect production costs. By precisely controlling the height of L, the amount of material used can be optimized while ensuring performance, thereby reducing production costs and improving economic benefits.

[0049] In another embodiment, the base portion 310 and the raised portion 320 are hollowed out, which can significantly reduce the volume of these components, thereby achieving a lightweight overall mechanical structure. Lightweighting is beneficial for improving the operating efficiency of the equipment, reducing energy consumption, and reducing material costs.

[0050] like Figure 1 As shown, in one embodiment, the raised portion 320 is arranged along a straight line. In another embodiment, two raised portions 320 are provided, and the two raised portions 320 and the base portion 310 form a Y-shaped structure.

[0051] like Figure 5As shown, in one embodiment, a plurality of protrusions 320 are provided, and the plurality of protrusions 320 form a connection group. The protrusions 320 in the same connection group are spaced apart, and the connection group is provided with at least one group, such as Figure 5 As shown, when there are two or more connection groups, the connection groups are spaced apart.

[0052] In a second aspect, an embodiment of the present application further provides a battery string, comprising a battery cell body 100 , wherein the number of the battery cell bodies 100 is at least two, and at least two battery cell bodies 100 are electrically connected.

[0053] Exemplarily, two battery cell bodies 100 are provided, and the two battery cell bodies 100 are electrically connected. In another embodiment, three battery cell bodies 100 are provided, and the three battery cell bodies 100 are electrically connected. In another embodiment, four battery cell bodies 100 are provided, and the four battery cell bodies 100 are electrically connected. Of course, in other embodiments, five, six, etc. battery cell bodies 100 may also be provided.

[0054] The battery string uses the battery cells provided in the embodiments of the present application, which can reduce manufacturing costs.

[0055] like Figure 1 As shown, in one embodiment, the battery string further includes a welding ribbon 400 , which is electrically connected to the pads 300 it passes through and connects every two adjacent battery cells in series.

[0056] In a third aspect, embodiments of the present application further provide a photovoltaic assembly, comprising a battery string according to any of the above embodiments. For example, the photovoltaic assembly secures the battery string via a structure such as a frame.

[0057] In a fourth aspect, embodiments of the present application further provide an electrical device comprising the photovoltaic assembly of any of the above embodiments. Exemplarily, the electrical device includes, but is not limited to, a battery, a motor, a vehicle, and the like.

[0058] It should be noted that, unless there is any conflict, the features in the embodiments of this application can be combined with each other.

[0059] The foregoing description is merely a preferred embodiment of the present application and is not intended to limit the present application. Persons skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A battery sheet, characterized by, Comprising: a cell body (100) for photovoltaic power generation, the cell body (100) having a functional end face; a sub-grid line (200) disposed on the functional end face in a first direction for collecting current on the cell; a main grid line disposed on the functional end face in a second direction, the main grid line being disposed crossing the sub-grid line (200), the main grid line being used for collecting current on the sub-grid line (200); a solder pad (300) comprising a base portion (310) and a raised portion (320), the base portion (310) being fixedly disposed at the intersection of the main grid line and the sub-grid line (200), the raised portion (320) being fixedly disposed on the base portion (310), the thickness of the raised portion (320) being less than the thickness of the base portion (310).

2. The battery sheet of claim 1, wherein, The first direction and the second direction have an included angle α, wherein 0° < α ≤ 90°.

3. The battery sheet of claim 1, wherein, The thickness of the raised portion (320) is H, the thickness of the base portion (310) is K, and the number of the raised portions (320) disposed on the base portion (310) is N, wherein N*H < K, 1 ≤ N, and N is an integer.

4. The battery sheet of claim 1, wherein, When the number of the raised portions (320) is more than two, the raised portions (320) are disposed at intervals.

5. The battery sheet of claim 1, wherein, The height of the raised portion (320) is E, the height of the base portion (310) is F, and the height of the sub-grid line (200) is L, wherein 4 μm ≤ E+F ≤ L.

6. The battery sheet of claim 5, wherein, 5 μm ≤ L ≤ 12 μm.

7. A battery string, characterized by Comprising: a plurality of cell bodies (100), the number of the cell bodies (100) being at least two, and the at least two cell bodies (100) being electrically connected.

8. The battery string of claim 7, wherein, Further comprising: a solder strip (400) electrically connected with the solder pad (300) passed thereby, and the solder strip (400) being connected in series with every adjacent two cells.

9. A photovoltaic module, characterized by Comprising: the cell string of any one of claims 7 to 8.

10. An electrical device, characterized by Comprising: the photovoltaic module of claim 9.

Images