Method for manufacturing lithium ion battery

Abstract

The application discloses a manufacturing method of a lithium ion battery, which comprises the following steps: providing an electric core, wherein the electric core comprises a positive electrode lug and a negative electrode lug; directly connecting a positive electrode terminal with the positive electrode lug to form a positive electrode part and directly connecting a negative electrode terminal with the negative electrode lug to form a negative electrode part, so that a connecting piece is saved; installing a first insulating piece, wherein the positive electrode part and the negative electrode part penetrate a first opening of the first insulating piece; installing a cover plate, wherein the positive electrode part and the negative electrode part penetrate a second opening of the cover plate; fixing the positive electrode part and the negative electrode part to prevent the positive electrode part and the negative electrode part from moving in a horizontal direction; pouring sealing material to package the second opening; adjusting the height of the positive electrode part and the negative electrode part before the sealing material solidifies; and solidifying the sealing material to form a second insulating piece, so that the application can simplify a structure assembly process, improve assembly consistency and improve the internal filling rate of the lithium ion battery.

Description

Technical Field

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

[0002] Energy storage refers to the process of storing energy through a medium or device and releasing it when needed. According to the energy storage method, energy storage can be divided into three categories: physical energy storage, chemical energy storage, and electromagnetic energy storage. Among them, chemical energy storage mainly includes lead-acid batteries, lithium-ion batteries, sodium-sulfur batteries, and flow batteries.

[0003] Lithium-ion batteries are efficient, environmentally friendly, and reliable energy storage devices. They feature high energy storage efficiency, high energy density, long lifespan, and no pollution, making them widely used in the energy storage field. Their energy storage principle involves the reciprocating movement of lithium ions between the positive and negative electrodes to store and release charge. During charging, lithium ions in the positive electrode material move towards the negative electrode, while electrons flow from the negative electrode to the positive electrode, storing charge. During discharging, the electron flow between the positive and negative electrodes causes lithium ions to move from the negative electrode to the positive electrode, releasing the stored charge. This process is reversible, allowing lithium-ion batteries to be repeatedly charged and discharged.

[0004] Lithium-ion batteries are mainly composed of components such as a top cover, outer casing, core, and connecting tabs. The positive and negative tabs on the core need to be connected to the connecting tabs, which in turn connect to the positive and negative terminals on the top cover. The assembly process of the top cover is complex and involves many parts. Moreover, the tabs on the battery cell need to be left long, resulting in insufficient space utilization.

[0005] Therefore, there is an urgent need to provide a method for manufacturing lithium-ion batteries that can simplify the assembly process and improve space utilization. Summary of the Invention

[0006] In view of this, the present invention provides a method for manufacturing a lithium-ion battery to prevent displacement of the positive and negative terminals and improve the yield of lithium-ion batteries.

[0007] The method for manufacturing a lithium-ion battery provided by this invention includes the following steps:

[0008] The battery cell is provided, with one end of the battery cell including a positive electrode tab and a negative electrode tab;

[0009] Provides a positive terminal and a negative terminal. The positive terminal is directly connected to the positive terminal tab to form a positive terminal component, and the negative terminal is directly connected to the negative terminal tab to form a negative terminal component.

[0010] A first insulating element is provided, the first insulating element is installed, and the positive electrode component and the negative electrode component pass through the first opening of the first insulating element;

[0011] Provide a cover plate, install the cover plate, and have the positive and negative electrode components pass through a second opening in the cover plate;

[0012] Fix the positive and negative electrode components to prevent them from moving horizontally;

[0013] Pour in sealing material to seal the second opening. Before the sealing material solidifies, adjust the height of the positive and negative electrode components.

[0014] The sealing material solidifies, forming a second insulating element.

[0015] Optionally, the positive terminal may be directly connected to the positive electrode tab by welding, and / or the negative terminal may be directly connected to the negative electrode tab by welding.

[0016] Optionally, the sealing material includes insulating adhesive, and sealing the second opening includes: pouring insulating adhesive and allowing the adhesive to cure to form a second insulating element.

[0017] Optionally, during assembly, the height difference between the first surface of the positive electrode component and / or the negative electrode component and the second surface of the second insulating component is not less than 0.5 mm, wherein the first surface is the surface of the positive electrode component and / or the negative electrode component away from the battery cell, and the second surface is the surface of the second insulating component away from the battery cell.

[0018] Optionally, during the pouring process, the second insulating component is controlled to protrude at least partially from the cover plate, and the height difference between the second surface of the second insulating component and the third surface of the cover plate is between 0.5mm and 4mm, with the third surface being the surface of the cover plate furthest from the battery cell.

[0019] Optionally, before installing the cover plate, the following may also be included: installing an explosion-proof valve on the cover plate.

[0020] Optionally, before the sealing material solidifies, adjust the height of the positive and negative electrode components, including:

[0021] The positive and negative electrode components are lifted to a height of 1mm-4.5mm from the cover plate.

[0022] Optionally, after directly connecting the positive terminal to the positive electrode tab to form a positive electrode component and directly connecting the negative terminal to the negative electrode tab to form a negative electrode component, and before installing the first insulating component, the method further includes: inserting the battery cell into the housing, with the positive electrode component and the negative electrode component located on one side of the opening end of the housing.

[0023] Optionally, after encapsulating the second opening, the method further includes: providing a housing, into which the battery cell with a positive electrode component, a negative electrode component, a first insulating component, a cover plate, and a second insulating component is integrally housed, with the positive electrode component and the negative electrode component located on one side of the opening end of the housing.

[0024] Optionally, the height of the positive and negative terminals can be between 5mm and 10mm.

[0025] Compared with the prior art, the method for manufacturing lithium-ion batteries provided by the present invention achieves at least the following beneficial effects:

[0026] In the manufacturing of lithium-ion batteries, this invention directly connects the positive terminal to the positive electrode tab to form the positive electrode component, and directly connects the negative terminal to the negative electrode tab to form the negative electrode component. This eliminates the need to first weld connectors to the positive and negative electrode tabs, and then connect the connectors to the positive and negative terminals respectively. This saves on connectors, which on the one hand reduces manufacturing processes, simplifies equipment processes, lowers material costs, and improves assembly consistency. On the other hand, the direct connection between the positive and negative terminals ensures a more stable connection, improving the reliability of the lithium-ion battery. Furthermore, the internal space of the casing is fully utilized, increasing the internal filling rate of the lithium-ion battery and thus enhancing its capacity.

[0027] The lithium-ion battery manufacturing method provided by this invention fixes the positive electrode component formed by the direct connection between the positive terminal and the positive electrode tab, and the negative electrode component formed by the direct connection between the negative terminal and the negative electrode tab, before the second opening is sealed with the sealing material. This prevents the positive and negative electrode components from moving horizontally. Then, the sealing material is poured to seal the second opening. Before the sealing material solidifies, the height of the positive and negative electrode components is adjusted, thereby preventing the positive and negative terminals from shifting horizontally and vertically. This solves the problem in the prior art where the elasticity of the tabs causes displacement of the positive and negative terminals, resulting in a low yield of lithium-ion batteries. This invention improves the yield of lithium-ion batteries.

[0028] Of course, any product implementing this invention does not necessarily need to achieve all of the technical effects described above at the same time.

[0029] Other features and advantages of the invention will become clear from the following detailed description of exemplary embodiments of the invention with reference to the accompanying drawings. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with their description, serve to explain the principles of the invention.

[0031] Figure 1 This is a flowchart of a method for manufacturing a lithium-ion battery provided by the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of a lithium-ion battery;

[0033] Figure 3 This is a split view of a lithium-ion battery;

[0034] Figure 4 This is a magnified view of a lithium-ion battery.

[0035] Figure 5 yes Figure 2 A cross-sectional view along line A-A' in the middle;

[0036] Figure 6 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention;

[0037] Figure 7 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention;

[0038] Figure 8 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention;

[0039] Figure 9 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention. Detailed Implementation

[0040] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that, unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps set forth in these embodiments do not limit the scope of the invention.

[0041] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the invention or its application or use.

[0042] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0043] In all the examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.

[0044] 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 discussed further in subsequent figures.

[0045] Reference Figure 1 , Figure 2 and Figure 3 , Figure 1 This is a flowchart of a method for manufacturing a lithium-ion battery provided by the present invention. Figure 2 This is a schematic diagram of the structure of a lithium-ion battery. Figure 3 This is a split diagram of a lithium-ion battery. Figure 1 The manufacturing method of lithium-ion batteries includes the following steps:

[0046] S1 provides a battery cell 06, one end of which includes a positive electrode tab 011 and a negative electrode tab 012;

[0047] S2 provides a positive terminal 04 and a negative terminal 05. The positive terminal 04 is directly connected to the positive terminal tab 011 to form a positive terminal component 08, and the negative terminal 05 is directly connected to the negative terminal tab 012 to form a negative terminal component 09.

[0048] S3, providing a first insulating member 03, mounting the first insulating member 03, and having the positive electrode component 08 and the negative electrode component 09 pass through the first opening 013 of the first insulating member 03;

[0049] S4, provide cover plate 02, install cover plate 02, positive electrode component 08 and negative electrode component 09 pass through the second opening 014 on cover plate 02;

[0050] S5, fix the positive electrode component 08 and the negative electrode component 09 to prevent the positive electrode component 08 and the negative electrode component 09 from moving in the horizontal direction;

[0051] S6, pour sealing material to seal the second opening 014, and adjust the height of the positive electrode component 08 and the negative electrode component 09 before the sealing material solidifies;

[0052] S7, the sealing material solidifies to form the second insulating element 01.

[0053] Specifically, in the battery cell 06 provided in step S1, the positive electrode tab 011 and the negative electrode tab 012 are located at the same end. The battery cell 06 can be manufactured by winding, which has higher production efficiency. The structure of the battery cell 06 adopts existing technology and is not specifically limited here. This invention does not improve the structure of the battery cell 06. Optionally, a multi-layer winding structure can be formed by winding a separator, positive electrode sheet, separator, negative electrode sheet, and separator in that order. After winding, the positive electrode tab 011 and the negative electrode tab 012 are welded to the same end of the winding structure. The positive electrode tab 011 may include aluminum (Al) material, and the negative electrode tab 012 may include nickel (Ni) material or copper-plated nickel (Ni-Cu) material.

[0054] Step S2 involves providing a positive terminal 04 and a negative terminal 05. The positive terminal 04 is directly connected to the positive electrode tab 011 to form a positive electrode component 08, and the negative terminal 05 is directly connected to the negative electrode tab 012 to form a negative electrode component 09. Because the positive terminal 04 and the positive electrode tab 011 are directly connected, the contact area between them is increased, as is the contact area between the negative terminal 05 and the negative electrode tab 012, resulting in a more stable connection and improving the yield rate of the lithium-ion battery. Optionally, the positive terminal 04 can be made of aluminum, and the negative terminal 05 can be made of copper or a copper-aluminum composite material.

[0055] Step S3: Provide a first insulating component 03. The first insulating component 03 can be a pre-formed part, such as a part injection molded from polypropylene material. During injection molding, a first opening 013 is reserved. The position of the first opening 013 matches the positive electrode component 08 and the negative electrode component 09. When installing the first insulating component 03, the first insulating component 03 is fitted into the positive electrode component 08 and the negative electrode component 09, so that the positive electrode component 08 and the negative electrode component 09 pass through the first opening 013 of the first insulating component 03. The shape of the first opening 013 is not specifically limited, as long as it matches the positive electrode component 08 and the negative electrode component 09.

[0056] Step S4: Provide a cover plate 02. The cover plate 02 can be made of aluminum, stainless steel, or carbon steel. A second opening 014 is pre-drilled in the cover plate 02. The shape of the second opening 014 is not specifically limited, as long as it matches the positive electrode component 08 and the negative electrode component 09. When installing the cover plate 02, fit the cover plate 02 onto the positive electrode component 08 and the negative electrode component 09, so that the positive electrode component 08 and the negative electrode component 09 pass through the second opening 014 of the first insulating member 03. That is, the first insulating member 03 and the cover plate 02 are sequentially installed on the battery cell 06 with the positive electrode component 08 and the negative electrode component 09. Optionally, the area of ​​the second opening 014 can be slightly larger than the area of ​​the positive electrode component 08 and the area of ​​the negative electrode component 09, so as to facilitate the positive electrode component 08 and the negative electrode component 09 passing through the second opening 014.

[0057] Step S5 involves fixing the positive electrode component 08 and the negative electrode component 09, thereby preventing them from moving horizontally. In related technologies, the positive electrode tab 011 and the negative electrode tab 012 are elastic, and displacement can occur when the positive electrode tab 011 is connected to the positive terminal 04 and the negative electrode tab 012 to the negative terminal 05 via the connector. Step S5, by fixing the positive electrode component 08 and the negative electrode component 09 horizontally, prevents horizontal displacement of the positive electrode component 08 and the negative electrode component 09, thus preventing a decrease in the yield rate of the lithium-ion battery.

[0058] Step S6: Pour sealing material to seal the second opening 014. In this invention, the second opening 014 is sealed by pouring sealing material. After the sealing material solidifies, the second opening 014 is sealed. As mentioned above, in related technologies, because the positive electrode tab 011 and the negative electrode tab 012 are elastic, displacement occurs when the positive electrode tab 011 and the positive terminal 04, and the negative electrode tab 012 and the negative terminal 05 are connected by the connector. This displacement occurs not only in the horizontal direction but also in the vertical direction. Because the tabs are elastic, and the simplified electrode post lacks vertical restraint, it may bulge upwards due to tension, such as... Figure 5 The direction of the arrow F affects the height control of the terminals (positive and negative electrode components). If the positive terminal 04 and the negative terminal 05 are displaced in the vertical direction, their final positions will deviate from the preset positions in the product, resulting in a decrease in the yield rate of lithium-ion batteries. In this embodiment, the height of the positive electrode component 08 and the negative electrode component 09 is adjusted before the sealing material solidifies. This prevents the positive electrode component 08 and the negative electrode component 09 from shifting in the height direction, thereby improving the yield rate of lithium-ion batteries.

[0059] In step S7, the sealing material solidifies to form the second insulating component 01. The second insulating component 01 is used to bond the positive electrode component 08, the negative electrode component 09, and the cover plate 02 together by pouring. The poured sealing material has good bonding force with the material of the cover plate 02, which meets the requirement that the lithium-ion battery casing can withstand a force of 1.2 MPa and meets the airtightness requirement.

[0060] Compared with related technologies, the lithium-ion battery manufacturing method provided in this embodiment has the following advantages:

[0061] Beneficial effects:

[0062] In this embodiment, when manufacturing a lithium-ion battery, the positive terminal 04 is directly connected to the positive electrode tab 011 to form the positive electrode component 08, and the negative terminal 05 is directly connected to the negative electrode tab 012 to form the negative electrode component 09. This eliminates the need to first weld the connector to the positive electrode tab 011 and the connector to the negative electrode tab 012, and then connect the connector to the positive terminal 04 and the connector to the negative terminal 05. This saves on connectors, which on the one hand reduces manufacturing processes, simplifies assembly processes, lowers material costs, and improves assembly consistency. On the other hand, the direct connection between the positive terminal 04 and the positive electrode tab 011, and the direct connection between the negative terminal 05 and the negative electrode tab 012, results in a more stable connection, improving the reliability of the lithium-ion battery. Furthermore, the internal space of the casing is fully utilized, increasing the cell filling rate within the casing, thereby increasing the battery capacity.

[0063] Before sealing the second opening 014 with the sealing material, the positive electrode component 08, formed by the direct connection between the positive terminal 04 and the positive electrode tab 011, and the negative electrode component 09, formed by the direct connection between the negative terminal 05 and the negative electrode tab 012, are fixed in place. This prevents the positive electrode component 08 and the negative electrode component 09 from moving in the horizontal direction. Then, the sealing material is poured in. Before the sealing material solidifies, the height of the positive electrode component 08 and the negative electrode component 09 is adjusted. This prevents the positive terminal 04 and the negative terminal 05 from shifting in the horizontal direction and in height. This solves the problem in the prior art where the positive terminal 04 and the negative terminal 05 shift due to the elasticity of the tabs, resulting in a low yield of lithium-ion batteries. The present invention improves the yield of lithium-ion batteries.

[0064] In some alternative embodiments, the positive terminal 04 is directly connected to the positive electrode tab 011 by welding, and / or the negative terminal 05 is directly connected to the negative electrode tab 012 by welding.

[0065] Optionally, the positive terminal 04 and the positive electrode tab 011 can be connected by welding, and the negative terminal 05 and the negative electrode tab 012 can also be connected by welding.

[0066] Welding offers excellent connection performance and can stably connect two structures even when they are made of different materials. The positive electrode tab 011 can be made of aluminum (Al), and the negative electrode tab 012 can be made of nickel (Ni) or nickel-plated copper (Ni-Cu). The positive terminal 04 can be made of aluminum, and the negative terminal 05 can be made of copper or a copper-aluminum composite material. Even if the negative terminal 05 and the negative electrode tab 012 are not made of the same material, welding can directly connect them without the need for additional connectors.

[0067] In some alternative embodiments, the sealing material includes an insulating adhesive, and encapsulating the second opening 014 includes: pouring the insulating adhesive and allowing it to cure to form a second insulating element 01.

[0068] The sealing material in this invention can be an insulating adhesive, which possesses good insulation, conformability, and integrity, as well as excellent heat resistance, thermal conductivity, and electrical properties. The casting process is simple and easily automated. To achieve good performance, the insulating adhesive is required to solidify rapidly, maintain good integrity, have low shrinkage, and not deform. It also needs high dielectric properties and moisture-proof and thermally conductive capabilities. Optionally, the insulating adhesive material can include polyester, epoxy, polyurethane, polybutadiene acid, silicone, polyesterimide, and polyimide, etc. The insulating adhesive can be poured into the second opening 014, and after curing, it forms the second insulating element 01, thereby sealing the second opening 014.

[0069] In some alternative embodiments, combined with Figure 4 , Figure 4 This is a partial enlarged view of a lithium-ion battery. During assembly, the height difference between the first surface 015 of the positive electrode component 08 and / or the negative electrode component 09 and the second surface 016 of the second insulating component 01 is controlled to be no less than 0.5 mm. The first surface 015 is the surface of the positive electrode component 08 and / or the negative electrode component 09 away from the cell 06, and the second surface 016 is the surface of the second insulating component 01 away from the cell 06.

[0070] It is understandable that the amount of sealing material poured should be moderate. If too much sealing material is poured, the height of the second insulating component 01 formed after the sealing material solidifies will be too high. At this time, the height difference between the second surface 016 of the second insulating component 01 and the first surface 015 of the control positive electrode component 08 and / or negative electrode component 09 will be too small, or the height of the second insulating component 01 may even be higher than the positive electrode component 08 or the negative electrode component 09, which will affect the conductivity of the positive electrode component 08 or the negative electrode component 09 of the lithium-ion battery. In this embodiment, when assembling a lithium-ion battery, the positions of the positive electrode component 08 and the negative electrode component 09 need to be fixed in the height direction using clips or other components. Then, a sealing material is poured in. After the sealing material solidifies, the first surface 015 of the positive electrode component 08 and / or the negative electrode component 09 is higher than the second surface 016 of the second insulating component 01. Preferably, the height difference between the first surface 015 of the positive electrode component 08 and / or the negative electrode component 09 and the second surface 016 of the second insulating component 01 is controlled to be no less than 0.5 mm. This ensures that the positive electrode component 08 or the negative electrode component 09 of the lithium-ion battery has good conductivity.

[0071] In some optional embodiments, during the pouring process, the second insulating member 01 is controlled to protrude at least partially from the cover plate 02, and the height difference between the second surface 016 of the second insulating member 01 and the third surface 017 of the cover plate 02 is between 0.5mm and 4mm, and the third surface 017 is the surface of the cover plate 02 away from the battery cell 06.

[0072] Optionally, the height difference between the second surface 016 of the second insulating member 01 and the third surface 017 of the cover plate 02 can be 0.5mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, or 1mm-3mm.

[0073] Understandably, the amount of sealing material poured must be sufficient to ensure good insulation of the second opening 014 on the cover plate 02. However, excessive pouring of sealing material will result in too small a height difference between the sealing material and the first surface 015 of the positive electrode component 08 and / or the negative electrode component 09, affecting the conductivity of the positive electrode component 08 or the negative electrode component 09 of the lithium-ion battery. In this embodiment, during the pouring process, the second insulating member 01 is controlled to at least partially protrude from the cover plate 02, and the height difference between the second surface 016 of the second insulating member 01 and the third surface 017 of the cover plate 02 is between 0.5mm and 4mm. This ensures both good conductivity of the positive electrode component 08 or the negative electrode component 09 of the lithium-ion battery and good insulation of the second opening 014 on the cover plate 02.

[0074] In some alternative embodiments, refer to Figure 6 , Figure 6 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention. Before installing the cover plate 02, the method further includes: installing an explosion-proof valve 010 on the cover plate 02.

[0075] Optionally, the explosion-proof valve 010 has an explosion-proof port machined on the cover plate 02, with a step on the explosion-proof port and an explosion-proof membrane installed on the step. The explosion-proof valve 010 utilizes the working principle of a positive temperature coefficient thermistor, where the resistance increases with higher temperatures and the thermistor does not conduct electricity. It can cut off the lithium-ion battery current circuit when the temperature sensed by the thermistor in the lithium-ion battery reaches a predetermined control temperature, thus improving the safety of the lithium-ion battery. Of course, a through hole 018 corresponding to the through hole is also required on the first insulating component 03.

[0076] In some alternative embodiments, refer to Figure 7 , Figure 7 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention. Before the sealing material solidifies, the heights of the positive electrode component 08 and the negative electrode component 09 are adjusted, including:

[0077] The positive electrode component 08 and the negative electrode component 09 are lifted to a height of 1mm-4.5mm from the cover plate 02.

[0078] Optionally, the positive electrode component 08 and the negative electrode component 09 can be picked up at a height of 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, or 4.5mm from the cover plate 02, or at a height of 2mm-4mm from the cover plate 02.

[0079] Optionally, the positive electrode component 08 and the negative electrode component 09 need to be fixed in the height direction. This improves the problem of displacement caused by the elasticity of the positive electrode tab 011 and the negative electrode tab 012. However, the height at which the positive electrode component 08 and the negative electrode component 09 are picked up cannot be too large or too small. If the height is too large, the positive electrode component 08 and the negative electrode component 09 will protrude too much from the cover plate 02, which may cause problems such as bending of the positive electrode component 08 and the negative electrode component 09 during use, resulting in instability of the lithium-ion battery. If the height is too small, the positive electrode component 08 and the negative electrode component 09 will not protrude enough from the cover plate 02, which may result in poor conductivity. In this embodiment, the positive electrode component 08 and the negative electrode component 09 can be picked up by the picking component to a height of 1mm-4.5mm from the cover plate 02. This ensures both conductivity and that the positive electrode component 08 and the negative electrode component 09 protrude from the cover plate 02 at a consistent height, making the lithium-ion battery more stable.

[0080] In some alternative embodiments, refer to Figure 8 , Figure 8 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention. After the positive terminal 04 is directly connected to the positive electrode tab 011 to form the positive electrode component 08, and the negative terminal 05 is directly connected to the negative electrode tab 012 to form the negative electrode component 09, before the first insulating component 03 is installed, the method further includes step S8: inserting the battery cell 06 into the housing 07, with the positive electrode component 08 and the negative electrode component 09 located on one side of the opening end of the housing 07.

[0081] In this embodiment, when assembling a lithium-ion battery, the positive terminal 04 and the positive electrode tab 011 are first connected to form a positive electrode component 08, and the negative terminal 05 and the negative electrode tab 012 are connected to form a negative electrode component 09. Then, the battery cell 06 is placed into the housing 07, and then the first insulating component 03, the cover plate 02, and the second insulating component 01 are installed in sequence to complete the assembly.

[0082] In some alternative embodiments, refer to Figure 9 , Figure 9 This is a flowchart of another method for manufacturing a lithium-ion battery provided by the present invention. After the second opening 014 is encapsulated, the method further includes step S9: providing a housing 07, and installing the battery cell 06, which has a positive electrode component 08, a negative electrode component 09, a first insulating component 03, a cover plate 02, and a second insulating component 01, into the housing 07. The positive electrode component 08 and the negative electrode component 09 are located on one side of the opening end of the housing 07.

[0083] In this embodiment, the positive terminal 04 and the positive electrode tab 011 are first connected to form the positive electrode component 08, and the negative terminal 05 and the negative electrode tab 012 are connected to form the negative electrode component 09. Then, the first insulating component 03 is installed, followed by the cover plate 02. Sealing material is poured to form the second insulating component 01. Finally, the battery cell 06, which includes the positive electrode component 08, the negative electrode component 09, the first insulating component 03, the cover plate 02, and the second insulating component 01, is installed into the housing 07.

[0084] This invention provides two different assembly methods, both of which are relatively simple and easy to operate, can reduce production costs, simplify production processes, and enable process diversity.

[0085] In some alternative embodiments, reference continues to be made to... Figure 3 The heights of the positive terminal 04 and the negative terminal 05 are between 5mm and 10mm.

[0086] Optionally, the heights of the positive terminal 04 and the negative terminal 05 are equal. For example, the heights of the positive terminal 04 and the negative terminal 05 can be 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, or 6mm-8mm.

[0087] The height of the positive terminal 04 and the negative terminal 05 cannot be too large or too small. If the height of the positive terminal 04 and the negative terminal 05 is too large, the positive electrode component 08 and the negative electrode component 09 will protrude excessively from the cover plate 02. This excessive protrusion of the positive electrode component 08 and the negative electrode component 09 will cause problems such as bending during use, leading to instability of the lithium-ion battery. If the height of the positive terminal 04 and the negative terminal 05 is too small, the positive electrode component 08 and the negative electrode component 09 will protrude insufficiently from the cover plate 02, potentially resulting in poor conductivity. The height of the positive terminal 04 and the negative terminal 05 should be between 5mm and 10mm. This ensures both good conductivity of the positive electrode component 08 and the appropriate protrusion height from the cover plate 02, resulting in a more stable lithium-ion battery.

[0088] As can be seen from the above embodiments, the method for manufacturing lithium-ion batteries provided by the present invention achieves at least the following beneficial effects:

[0089] In the manufacturing of lithium-ion batteries, this invention directly connects the positive terminal to the positive electrode tab to form the positive electrode component, and directly connects the negative terminal to the negative electrode tab to form the negative electrode component. This eliminates the need to first weld connectors to the positive and negative electrode tabs, and then connect the connectors to the positive and negative terminals respectively. This saves on connectors, simplifying the manufacturing process, reducing material costs, and ensuring a more stable connection between the positive and negative terminals, thus improving the reliability of the lithium-ion battery. Furthermore, the internal space of the casing is fully utilized, increasing the internal filling rate and ultimately enhancing the battery capacity.

[0090] The lithium-ion battery manufacturing method provided by this invention fixes the positive electrode component formed by the direct connection between the positive terminal and the positive electrode tab, and the negative electrode component formed by the direct connection between the negative terminal and the negative electrode tab, before the second opening is sealed with the sealing material. This prevents the positive and negative electrode components from moving horizontally. Then, the sealing material is poured to seal the second opening. Before the sealing material solidifies, the height of the positive and negative electrode components is adjusted, thereby preventing the positive and negative terminals from shifting horizontally and vertically. This solves the problem in the prior art where the elasticity of the tabs causes displacement of the positive and negative terminals, resulting in a low yield of lithium-ion batteries. This invention improves the yield of lithium-ion batteries.

[0091] While specific embodiments of the invention have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of the invention. Those skilled in the art should understand that modifications can be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A method for manufacturing a lithium-ion battery, characterized in that, Including the following steps: A battery cell is provided, one end of which includes a positive electrode tab and a negative electrode tab; A positive terminal and a negative terminal are provided. The positive terminal is directly connected to the positive terminal tab to form a positive terminal component, and the negative terminal is directly connected to the negative terminal tab to form a negative terminal component. A first insulating element is provided, and the first insulating element is installed, wherein the positive electrode component and the negative electrode component pass through a first opening in the first insulating element; A cover plate is provided, and the cover plate is installed, with the positive electrode component and the negative electrode component passing through a second opening in the cover plate; The positive electrode component and the negative electrode component are fixed to prevent them from moving in the horizontal direction; Pour in sealing material to seal the second opening; Before the sealing material solidifies, the height of the positive electrode component and the negative electrode component is adjusted, which includes: lifting the positive electrode component and the negative electrode component to a height of 1mm-4.5mm from the cover plate; The sealing material solidifies to form a second insulating component; during assembly, the height difference between the first surface of the positive electrode component and / or the negative electrode component and the second surface of the second insulating component is controlled to be no less than 0.5 mm, wherein the first surface is the surface of the positive electrode component and / or the negative electrode component away from the battery cell, and the second surface is the surface of the second insulating component away from the battery cell; During the pouring process, the second insulating component is controlled to protrude at least partially from the cover plate. The height difference between the second surface of the second insulating component and the third surface of the cover plate is between 0.5 mm and 4 mm. The third surface is the surface of the cover plate away from the battery cell.

2. The method for manufacturing a lithium-ion battery according to claim 1, characterized in that, The positive terminal is directly connected to the positive electrode tab by welding, and / or the negative terminal is directly connected to the negative electrode tab by welding.

3. The method for manufacturing a lithium-ion battery according to claim 1, characterized in that, The sealing material includes an insulating adhesive, and sealing the second opening includes: pouring the insulating adhesive and allowing it to cure to form the second insulating component.

4. The method for manufacturing a lithium-ion battery according to claim 1, characterized in that, Before installing the cover plate, the method further includes: installing an explosion-proof valve on the cover plate.

5. The method for manufacturing a lithium-ion battery according to claim 1, characterized in that, After the step of directly connecting the positive terminal to the positive electrode tab to form a positive electrode component and directly connecting the negative terminal to the negative electrode tab to form a negative electrode component, and before installing the first insulating component, the method further includes: inserting the battery cell into the housing, with the positive electrode component and the negative electrode component located on one side of the opening end of the housing.

6. The method for manufacturing a lithium-ion battery according to claim 1, characterized in that, After sealing the second opening, the method further includes: providing a housing, and inserting the battery cell with the positive electrode component, the negative electrode component, the first insulating component, the cover plate and the second insulating component into the housing, wherein the positive electrode component and the negative electrode component are located on one side of the opening end of the housing.

7. The method for manufacturing a lithium-ion battery according to claim 1, characterized in that, The height of the positive and negative terminals is between 5mm and 10mm.

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