A method for manufacturing a battery cell stack

Abstract

The application discloses a kind of electric core cutting and folding manufacturing method, it is related to lithium battery technical field.First, the stacking layer coiled material is unwound and cut, to form multiple stacking layers;Subsequently, multiple stacking layers are stacked and combined to form electric core.Compared with prior art, the electric core cutting and folding manufacturing method provided by the application can manufacture electric core with higher output voltage, reduce the overall resistance of electric core, and improve the energy density of electric core because of the step of stacking and combining multiple stacking layers to form electric core.

Description

Technical Field

[0001] This invention relates to the field of lithium battery technology, and more specifically, to a method for manufacturing cell stacking. Background Technology

[0002] With the development of science and technology, lithium batteries are used as power sources in many fields such as digital products, military industry, and new energy vehicles. As a result, the lithium battery industry has developed rapidly in recent years, and cell manufacturing is an important part of lithium battery production. Currently, conventional cell manufacturing methods produce cells with relatively low output voltages. In daily use, multiple cells are usually connected in series to ensure that the overall output voltage meets the requirements. However, this results in a complex series structure that is difficult to implement and has high material costs.

[0003] In view of this, designing a cell stacking manufacturing method that can improve the cell output voltage is particularly important in cell production. Summary of the Invention

[0004] The purpose of this invention is to provide a method for manufacturing battery cells by cutting and stacking, which can produce battery cells with higher output voltage, reduce the overall resistance of the battery cells, and increase the energy density of the battery cells.

[0005] The present invention is achieved by the following technical solution.

[0006] A method for manufacturing battery cells by cutting and stacking includes: unwinding and cutting a roll of stacked material to form multiple stacked layers; and stacking the multiple stacked layers together to form a battery cell.

[0007] Optionally, the stacked layer roll includes a first stacked layer roll and a second stacked layer roll. The step of unwinding and cutting the stacked layer roll to form multiple stacked layers includes: unwinding and cutting the first stacked layer roll along a first direction to form multiple first stacked layers; unwinding and cutting the second stacked layer roll along a second direction to form multiple second stacked layers; wherein the first direction and the second direction are set at a preset angle.

[0008] Optionally, the preset angle ranges from 30 degrees to 180 degrees.

[0009] Optionally, the step of stacking multiple stacked layers to form a battery cell includes: stacking multiple first stacked layers and multiple second stacked layers alternately in sequence.

[0010] Optionally, both the first stacked layer and the second stacked layer are composite electrodes, and the composite electrode includes a second active material layer, a first composite current collector layer, a first active material layer and a first electrolyte membrane stacked sequentially.

[0011] Optionally, the first active material layer is made of lithium metal or graphite material, and the second active material layer is made of lithium iron phosphate or ternary material.

[0012] Optionally, the areas of the second active material layer and the first composite current collector layer are equal, the areas of the first active material layer and the first electrolyte membrane are equal, and the area of ​​the first active material layer is greater than the area of ​​the second active material layer.

[0013] Optionally, the first stacked layer is a positive electrode sheet with a positive tab, and the second stacked layer is a negative electrode sheet with a negative tab.

[0014] Optionally, after the step of stacking multiple layers to form a battery cell, the battery cell cutting and stacking manufacturing method further includes: sequentially attaching a second electrolyte membrane, a third active material layer, and a second composite current collector layer to one side of the battery cell, and sequentially attaching a fourth active material layer and a third composite current collector layer to the other side of the battery cell.

[0015] Optionally, the second composite current collector layer is provided with a first electrode tab, and the third composite current collector layer is provided with a second electrode tab, wherein the first electrode tab and the second electrode tab have opposite polarities.

[0016] The cell stacking manufacturing method provided by this invention has the following beneficial effects:

[0017] The battery cell cutting and stacking manufacturing method provided by this invention first unwinds and cuts the stacked layer roll to form multiple stacked layers; then, the multiple stacked layers are stacked and compounded to form a battery cell. Compared with the prior art, the battery cell cutting and stacking manufacturing method provided by this invention, by employing the step of stacking and compounding multiple stacked layers to form a battery cell, can manufacture battery cells with higher output voltage, reduce the overall resistance of the battery cell, and increase the energy density of the battery cell. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a flowchart illustrating the steps of a cell cutting and stacking manufacturing method provided in the first embodiment of the present invention.

[0020] Figure 2 A schematic diagram of the structure of a battery cell production line used in the battery cell cutting and stacking manufacturing method provided in the first embodiment of the present invention;

[0021] Figure 3This is a schematic diagram of the structure of a battery cell manufactured by the battery cell cutting and stacking manufacturing method provided in the first embodiment of the present invention;

[0022] Figure 4 A schematic diagram of the structure of a battery cell production line used in the battery cell cutting and stacking manufacturing method provided in the second embodiment of the present invention;

[0023] Figure 5 This is a schematic diagram of the structure of a battery cell manufactured by the battery cell cutting and stacking manufacturing method provided in the second embodiment of the present invention;

[0024] Figure 6 A schematic diagram of the structure of a battery cell production line used in the battery cell cutting and stacking manufacturing method provided in the third embodiment of the present invention;

[0025] Figure 7 This is a schematic diagram of the structure of a battery cell manufactured by the battery cell cutting and stacking manufacturing method provided in the third embodiment of the present invention.

[0026] Icons: 100 - Battery cell; 110 - Stacked layer roll; 111 - First stacked layer roll; 112 - Second stacked layer roll; 120 - Stacked layer; 121 - Composite electrode; 122 - First active material layer; 123 - First composite current collector layer; 124 - Second active material layer; 125 - First electrolyte membrane; 126 - First stacked layer; 127 - Second stacked layer; 128 - Positive electrode; 129 - Negative electrode; 131 - Positive tab; 132 - Negative tab; 133 - Second electrolyte membrane; 134 - Second composite current collector layer; 135 - Third composite current collector layer; 136 - First tab; 137 - Second tab; 138 - Third active material layer; 139 - Fourth active material layer; 200 - Cutting mechanism. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, 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. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0028] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0029] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0030] In the description of this invention, it should be noted that the terms "inner," "outer," "upper," "lower," "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of the invention is in use. They are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. In addition, the terms "first," "second," "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0031] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," "installed," and "connected" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0032] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, features in the following embodiments can be combined with each other.

[0033] First Embodiment

[0034] Please refer to the reference. Figure 1 , Figure 2 and Figure 3 ( Figure 2 (The hollow arrow in the diagram indicates the direction of the conveyor belt). This embodiment of the invention provides a method for manufacturing battery cells by cutting and stacking, for manufacturing battery cells 100. It can produce battery cells 100 with higher output voltage, reduce the overall resistance of battery cells 100, and increase the energy density of battery cells 100.

[0035] It should be noted that the cell cutting and stacking manufacturing method is applied to the cell production line. The cell production line can use the cell cutting and stacking manufacturing method to process each layer of raw materials to produce cell 100. Cell 100 has a high output voltage, low overall resistance, and high energy density.

[0036] The cell stacking manufacturing method includes the following steps:

[0037] Step S110: Unwind and cut the stacked layer roll 110 to form multiple stacked layers 120.

[0038] It should be noted that in step S110, the feeding mechanism first drives the stacked layer roll 110 to unwind and send it to the corresponding position of the cutting mechanism 200; then the cutting mechanism 200 cuts it into multiple pieces of equal area, thus forming multiple stacked layers 120.

[0039] In this embodiment, the stacked layer 120 is a composite electrode 121, which includes a second active material layer 124, a first composite current collector layer 123, a first active material layer 122, and a first electrolyte membrane 125 stacked sequentially. Specifically, the second active material layer 124 is made of lithium iron phosphate or ternary materials, the first active material layer 122 is made of lithium metal or graphite, and the first composite current collector layer 123 is made of aluminum or an aluminum-copper alloy.

[0040] In this embodiment, the areas of the first active material layer 122, the first composite current collector layer 123, the second active material layer 124, and the first electrolyte membrane 125 are all equal.

[0041] Specifically, in the process of manufacturing the composite electrode 121, a first active material layer 122 and a second active material layer 124 are first coated on both sides of the first composite current collector layer 123, respectively; then the side of the first active material layer 122 away from the first composite current collector layer 123 is directly bonded to the first electrolyte membrane 125 to form the composite electrode 121.

[0042] Step S120: Stack multiple stacked layers 120 together to form a battery cell 100.

[0043] It should be noted that in step S120, the stacked layer 120 is first clamped and fed forward by the wafer feeding mechanism; when the stacked layer 120 moves to the preset position, the wafer feeding mechanism is controlled to place the stacked layer 120 on the stacking platform; this is repeated to stack multiple stacked layers 120; then the multiple stacked layers 120 are combined to form a cell 100.

[0044] Specifically, the number of stacked layers 120 is determined by the required output voltage of the battery cell 100; that is, the number of stacked layers 120 in the battery cell 100 is different for different output voltages. The more stacked layers 120 there are, the higher the output voltage of the battery cell 100; the fewer stacked layers 120 there are, the lower the output voltage of the battery cell 100.

[0045] Step S130: On one side of the battery cell 100, a second electrolyte membrane 133, a third active material layer 138, and a second composite current collector layer 134 are sequentially attached, and on the other side of the battery cell 100, a fourth active material layer 139 and a third composite current collector layer 135 are sequentially attached.

[0046] It should be noted that in step S130, the two outermost layers of the battery cell 100 are the second active material layer 124 and the first electrolyte membrane 125, respectively. A second electrolyte membrane 133, a third active material layer 138, and a second composite current collector layer 134 are sequentially attached to the outermost second active material layer 124. A fourth active material layer 139 and a third composite current collector layer 135 are sequentially attached to the outermost first electrolyte membrane 125. The third active material layer 138 is identical to the first active material layer 122, and the fourth active material layer 139 is identical to the second active material layer 124.

[0047] Specifically, in the process of attaching the second electrolyte membrane 133, the third active material layer 138, and the second composite current collector layer 134, or attaching the fourth active material layer 139 and the third composite current collector layer 135, the same three steps of unwinding, cutting, and lamination are required. Taking the attachment of the second electrolyte membrane 133 as an example, firstly, the feeding mechanism drives the second electrolyte membrane roll to unwind and sends it to the corresponding position of the cutting device; then, the cutting device cuts it into multiple pieces of equal area, thus forming multiple second electrolyte membranes 133; finally, the second electrolyte membrane 133 is laminated to the outermost second active material layer 124 of the battery cell 100.

[0048] In this embodiment, the second composite current collector layer 134 is provided with a first tab 136, and the third composite current collector layer 135 is provided with a second tab 137. The first tab 136 and the second tab 137 have opposite polarities. The first tab 136 and the second tab 137 work together to serve as the external tabs of the entire cell 100. In this way, there are no tabs occupying space inside the cell 100, which can effectively improve the energy density of the cell 100. Furthermore, since there are no tabs inside the cell 100 to collect current and generate heat, the contact between the layers is uniform, so the cell 100 has high reliability and good consistency.

[0049] It is worth noting that, because the electrolyte membrane can conduct protons and ions while isolating electrons, and because there are no tabs inside the cell 100 and the internal structure of the cell 100 is a series structure, the cell 100 manufactured by the cell stacking manufacturing method has a higher output voltage, a shorter electron flow path, a lower overall resistance, and a higher energy density.

[0050] The battery cell cutting and stacking manufacturing method provided in this embodiment of the invention first unwinds and cuts the stacked layer roll 110 to form multiple stacked layers 120; then, the multiple stacked layers 120 are stacked and compounded to form a battery cell 100. Compared with the prior art, the battery cell cutting and stacking manufacturing method provided by this invention, by employing the step of stacking and compounding multiple stacked layers 120 to form a battery cell 100, can manufacture a battery cell 100 with a higher output voltage, reduce the overall resistance of the battery cell 100, and increase the energy density of the battery cell 100.

[0051] Second Embodiment

[0052] Please refer to the reference. Figure 4 and Figure 5 ( Figure 4 The hollow arrow in the figure indicates the direction of the conveyor belt. This embodiment of the invention provides a method for manufacturing battery cell stacking. Compared with the first embodiment, the difference in this embodiment is that steps S110 and S120 are different.

[0053] In this embodiment, the stacked layer roll 110 includes a first stacked layer roll 111 and a second stacked layer roll 112, and the stacked layer 120 includes a first stacked layer 126 and a second stacked layer 127. Specifically, the first stacked layer 126 and the second stacked layer 127 are both composite electrode sheets 121, and the composite electrode sheet 121 includes a second active material layer 124, a first composite current collector layer 123, a first active material layer 122 and a first electrolyte membrane 125 stacked sequentially.

[0054] In this embodiment, the areas of the second active material layer 124 and the first composite current collector layer 123 are equal, the areas of the first active material layer 122 and the first electrolyte membrane 125 are equal, and the area of ​​the first active material layer 122 is greater than the area of ​​the second active material layer 124.

[0055] It should be noted that in step S110, the first stacked layer roll 111 is unwound and cut along the first direction to form a plurality of first stacked layers 126; the second stacked layer roll 112 is unwound and cut along the second direction to form a plurality of second stacked layers 127; wherein the first direction and the second direction are set at a preset angle.

[0056] Specifically, the preset angle ranges from 30 degrees to 180 degrees. A reasonable preset angle can ensure the manufacturing efficiency of the battery cell 100 while meeting the space requirements. In this embodiment, the preset angle is 30 degrees, but it is not limited to this. In other embodiments, the preset angle can be 90 degrees or 180 degrees. The size of the preset angle is not specifically limited.

[0057] It should be noted that in step S120, multiple first stacked layers 126 and multiple second stacked layers 127 are stacked alternately in sequence. Specifically, firstly, a feeding mechanism is used to clamp and feed the first stacked layer 126 forward. When the first stacked layer 126 moves to a preset position, the feeding mechanism is controlled to place the first stacked layer 126 on the stacking platform. Then, another feeding mechanism is used to clamp and feed the second stacked layer 127 forward. When the second stacked layer 127 moves to a preset position, the feeding mechanism is controlled to place the second stacked layer 127 on top of the first stacked layer 126. This process is repeated to alternately overlap and place multiple first stacked layers 126 and multiple second stacked layers 127 in sequence. Then, the multiple first stacked layers 126 and multiple second stacked layers 127 are combined to form the battery cell 100.

[0058] The beneficial effects of the cell cutting and stacking manufacturing method provided in this embodiment of the invention are the same as those in the first embodiment, and will not be repeated here.

[0059] Third Embodiment

[0060] Please refer to the reference. Figure 6 and Figure 7 ( Figure 6 The hollow arrow in the figure indicates the direction of the conveyor belt. This embodiment of the invention provides a method for manufacturing battery cell stacking. Compared with the second embodiment, the difference in this embodiment is that step S110 is different.

[0061] In this embodiment, the first stacked layer 126 is a positive electrode 128, and the positive electrode 128 is provided with a positive electrode tab 131. The second stacked layer 127 is a negative electrode 129, and the negative electrode 129 is provided with a negative electrode tab 132. Specifically, the positive electrode 128 includes a second active material layer 124, a first composite current collector layer 123, a first active material layer 122, and a first electrolyte membrane 125 stacked sequentially, wherein the first composite current collector layer 123 is provided with a positive electrode tab 131; the negative electrode 129 includes a second active material layer 124, a first composite current collector layer 123, a first active material layer 122, and a first electrolyte membrane 125 stacked sequentially, wherein the first composite current collector layer 123 is provided with a negative electrode tab 132.

[0062] It should be noted that in step S110, the preset angle formed between the first direction and the second direction is 180 degrees, that is, the first stacked layer roll 111 and the second stacked layer roll 112 are unwound in opposite directions, so as to meet the site space requirements while ensuring the manufacturing efficiency of the battery cell 100.

[0063] In this embodiment, the areas of the first active material layer 122, the first composite current collector layer 123, the second active material layer 124, and the first electrolyte membrane 125 are all equal in both the positive electrode 128 and the negative electrode 129.

[0064] The beneficial effects of the cell cutting and stacking manufacturing method provided in this embodiment of the invention are the same as those in the second embodiment, and will not be repeated here.

[0065] The above are merely preferred embodiments of the present invention and are not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for manufacturing battery cells by cutting and stacking, characterized in that, include: Unwinding and cutting the stacked layer roll (110) to form multiple stacked layers (120) includes: the stacked layer roll (110) includes a first stacked layer roll (111) and a second stacked layer roll (112); unwinding and cutting the first stacked layer roll (111) along a first direction to form multiple first stacked layers (126); unwinding and cutting the second stacked layer roll (112) along a second direction to form multiple second stacked layers (127); wherein the first direction and the second direction are set at a preset angle, and the preset angle ranges from 30 degrees to 180 degrees; Both the first stacked layer (126) and the second stacked layer (127) are composite electrodes (121). The composite electrode (121) includes a second active material layer (124), a first composite current collector layer (123), a first active material layer (122), and a first electrolyte membrane (125) stacked sequentially. The areas of the second active material layer (124) and the first composite current collector layer (123) are equal, the areas of the first active material layer (122) and the first electrolyte membrane (125) are equal, and the area of ​​the first active material layer (122) is greater than the area of ​​the second active material layer (124). Stacking multiple stacked layers (120) to form a cell (100) includes: sequentially and alternately stacking multiple first stacked layers (126) and multiple second stacked layers (127); A second electrolyte membrane (133), a third active material layer (138), and a second composite current collector layer (134) are sequentially attached to one side of the battery cell (100), and a fourth active material layer (139) and a third composite current collector layer (135) are sequentially attached to the other side of the battery cell (100). The second composite current collector layer (134) is provided with a first tab (136), and the third composite current collector layer (135) is provided with a second tab (137). The first tab (136) and the second tab (137) have opposite polarities.

2. The cell stacking manufacturing method according to claim 1, characterized in that, The first active material layer (122) is made of lithium metal or graphite material, and the second active material layer (124) is made of lithium iron phosphate or ternary material.

3. The cell stacking manufacturing method according to claim 1, characterized in that, The first stacked layer (126) is a positive electrode (128), and the positive electrode (128) is provided with a positive electrode tab (131). The second stacked layer (127) is a negative electrode (129), and the negative electrode (129) is provided with a negative electrode tab (132).

Images