Injection method and equipment
By applying pressure to the large surface of the battery and combining it with negative pressure pumping, the problem of gas venting from the flexible shell cell was solved, achieving efficient electrolyte wetting and mixing, and improving electrolyte injection efficiency and battery performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- CONTEMPORARY AMPEREX TECHNOLOGY CO LTD
- Filing Date
- 2026-01-30
- Publication Date
- 2026-05-26
AI Technical Summary
Existing negative pressure devices cannot effectively remove gas from inside cells with flexible shells during liquid injection production.
By applying pressure to the large surface of the battery and using negative pressure to pump air, primary and secondary electrolytes are injected sequentially. The combined effect of pressure and negative pressure is used to expel the gas inside the battery and promote the electrolyte in the electrode to become free electrolyte, thus achieving full mixing and wetting of the electrolyte.
It improves the wetting speed and efficiency of the electrolyte, reduces residual air bubbles, enhances the quality of electrolyte injection, and reduces the risk of gas expansion in subsequent battery cycles.
Smart Images
Figure CN121601995B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of battery technology, and in particular to a liquid injection method and apparatus. Background Technology
[0002] For battery cells with flexible shells, a negative pressure device is needed to expel the internal gas during the liquid injection process.
[0003] The negative pressure device in the related technology cannot effectively expel the gas inside the battery cell during use. Summary of the Invention
[0004] In view of the above problems, this application provides a liquid injection method and device that can solve the problem that the negative pressure device cannot effectively expel the gas inside the battery cell during use.
[0005] To address the aforementioned technical problems, this application proposes a liquid injection method, which includes the following steps:
[0006] The large surface of the battery is fixed in the fixture, and a compressive force is applied to the first area of the large surface of the battery.
[0007] The gas inside the battery is expelled by using negative pressure suction and clamps to squeeze it out;
[0008] After injecting electrolyte into the battery once, the formation process is completed.
[0009] After formation is completed, during the second liquid injection, a squeezing pressure is continued to be applied to the first area of the large surface of the battery.
[0010] The gas inside the electrode is discharged by negative pressure suction combined with the squeezing force of the clamp, and some of the electrolyte inside the electrode is squeezed out to become free electrolyte.
[0011] Secondary electrolyte is injected into the battery. After the secondary electrolyte and free electrolyte are mixed by convection, the corresponding squeezing pressure is removed.
[0012] In the technical solution of this application embodiment, during the first injection of electrolyte, the first area of the flexible shell on the battery deforms under the action of extrusion force, and the gas inside the battery exchanges with the primary electrolyte. The gas is discharged outward, reserving space for electrolyte wetting, thereby improving the electrolyte wetting speed. When the electrolyte is injected for the second time, the battery continues to be subjected to extrusion force, and the gas and part of the electrolyte inside the electrode are squeezed out. At this time, the squeezed-out free electrolyte will be fully mixed with the secondary electrolyte after convection to complete the injection. After the injection is completed, the flexible shell returns to its initial state. In the overall process, by applying extrusion force to the large first area of the flexible shell on the battery in combination with negative pressure suction, the gas inside the battery can be effectively discharged, thereby improving the wetting efficiency.
[0013] In some embodiments, the injection of a primary electrolyte into the battery includes:
[0014] Connect the electrolyte filling cup to the battery filling port, and inject electrolyte into the electrolyte filling cup.
[0015] The clamp continuously applies compressive force;
[0016] After the primary electrolyte reaches the specified amount, the electrolyte valve is opened and the primary electrolyte is injected into the battery through high pressure.
[0017] Repeatedly use negative pressure suction and clamps to squeeze out the gas inside the battery until all the gas inside the battery is expelled.
[0018] In this way, electrolyte is injected into the battery sequentially through high pressure, and the gas inside the battery is expelled by repeated negative pressure pumping and clamping. This can effectively remove the gas inside the battery.
[0019] In some embodiments, the clamp continuously applies a compressive force, including:
[0020] The clamp applies compressive force to the first area of the large surface of the battery;
[0021] The extrusion pressure is matched with the negative pressure value at the injection port.
[0022] The negative pressure at the electrolyte filling port is designed to draw out gas from the battery, while the clamping force causes a directional indentation in the first area of the battery's surface. This facilitates the extraction of gas from the electrode pores and separator folds. Because the clamping force is matched with the corresponding negative pressure value, it further promotes the expulsion of gas from the battery, thereby reducing residual air bubbles inside the battery after electrolyte filling.
[0023] When the negative pressure is too high and the compressive force is insufficient, the battery will undergo localized deformation due to the excessive pressure difference between the inside and outside. When the compressive force is too high and the negative pressure is insufficient, the gaps between the electrodes are excessively compressed, making it difficult for the electrolyte to penetrate into the pores inside the electrodes. When the compressive force and negative pressure are matched, the battery's indentation deformation is controllable, and the gaps between the electrodes are in the optimal range for electrolyte penetration. This allows for deep wetting without repeated pumping and electrolyte injection, improving electrolyte injection efficiency.
[0024] In some embodiments, the step of discharging gas from the electrode by negative pressure suction combined with clamping force and causing a portion of the electrolyte within the electrode to be squeezed out as free electrolyte includes:
[0025] Open the battery vent and continuously apply compressive force through the clamp to drive the battery surface to indent inward.
[0026] Under the action of negative pressure and clamping force, the gas inside the electrode is discharged, and at the same time, part of the primary electrolyte inside the electrode is squeezed out, becoming free electrolyte.
[0027] In this way, after the first electrolyte injection, although the electrolyte has wetted the electrode, some electrolyte remains trapped in the electrode pores and separator micropores due to capillary action and adsorption. The flow and diffusion of electrolyte are restricted by the complex pore structure of the electrode and separator, resulting in an inconsistency between the composition of the free electrolyte and the electrolyte inside the electrode, affecting battery performance. By using the combined action of clamping force and negative pressure, the primary electrolyte inside the electrode is squeezed out into free electrolyte, allowing this portion of electrolyte to enter the free space of the battery cavity. At this time, the injected secondary electrolyte will form directional convection with the free electrolyte, which is conducive to the rapid diffusion and uniform fusion of the two electrolytes. At the same time, during the process of squeezing out the electrolyte inside the electrode, the electrode pores will undergo expansion and contraction deformation, and the tiny air bubbles trapped in the electrolyte will be squeezed out simultaneously. After entering the free space, they will be quickly drawn away by the negative pressure. Meanwhile, the flow of free electrolyte will also carry air bubbles towards the exhaust port, achieving deep gas removal.
[0028] In some embodiments, the injection of secondary electrolyte into the battery, followed by the release of the corresponding squeezing pressure after the secondary electrolyte and free electrolyte have been convectively mixed, includes:
[0029] Connect the injection cup to the battery injection port, and inject a specified amount of secondary electrolyte into the injection cup;
[0030] The secondary electrolyte is injected into the battery under high voltage.
[0031] After the secondary electrolyte and the free electrolyte are convectively mixed, the corresponding extrusion pressure is removed.
[0032] In this way, high pressure is used to inject the secondary electrolyte into the battery, directly driving the free electrolyte to form forced convection, breaking the limitations of molecular diffusion, and allowing the two electrolytes to fully fuse in a very short time. This ensures that the solute concentration of the mixed electrolyte is consistent throughout the entire battery. Moreover, the high-pressure injected secondary electrolyte carries the mixed electrolyte to apply directional pressure to the wetting blind area, forcing it to penetrate into the deep pores of the electrode and the micropores of the separator, filling the defects of the primary wetting, achieving full coating of the active material of the electrode, and improving the utilization rate of the active material. Because the clamp still applies extrusion pressure to the large surface of the battery during secondary injection, the internal pressure of the battery cavity is higher than the atmospheric pressure. The pressure value of the high-pressure injection can match the cavity pressure generated by the clamp extrusion, ensuring that the secondary electrolyte can be injected into the battery stably and quantitatively, avoiding insufficient or excessive injection. Meanwhile, the high-pressure injected electrolyte flows faster, and the high-pressure environment causes the gas dissolved in the electrolyte to be quickly released and float to the exhaust port area. Combined with the negative pressure suction, these gases can be discharged from the battery in time, avoiding bubbles from being trapped between the electrode and the separator, and reducing the risk of gas expansion in subsequent battery cycles.
[0033] This application also proposes a liquid injection device, comprising:
[0034] The clamp is configured to hold a first region of the large surface of the battery, and a drive member drives the clamp to apply a compressive force to the first region of the large surface of the battery.
[0035] The negative pressure extraction device is configured to extract air from the battery.
[0036] The primary electrolyte injection unit is configured to inject electrolyte into the battery through the injection nozzle assembly and complete the formation process.
[0037] The secondary electrolyte injection unit is configured to inject secondary electrolyte into the battery through the injection nozzle assembly.
[0038] In this way, the clamp is moved by the drive component to adjust the squeezing force of the clamp on the large surface of the battery, thereby facilitating the discharge of gas from the battery.
[0039] In some embodiments, the clamp includes a fixed base, a first clamping arm, and a second clamping arm, wherein the first clamping arm and / or the second clamping arm are slidably connected to the fixed base;
[0040] The drive unit cooperates with the first clamping arm and the second clamping arm and is configured to drive the first clamping arm and the second clamping arm to move closer to or further away from each other.
[0041] In some embodiments, a first pad is provided on the side of the first clamping arm facing the second clamping arm, and a second pad is provided on the side of the second clamping arm facing the first clamping arm.
[0042] The first pad and the second pad are respectively matched with the first region.
[0043] Since the first pad and the second pad are respectively matched with the first region, it is convenient to apply compressive force to the first region.
[0044] In some embodiments, a flexible layer is provided on the side of the first pad facing the second pad and on the side of the second pad facing the first pad.
[0045] The flexible layer helps prevent large-scale damage to the battery.
[0046] In some embodiments, the liquid injection device further includes a connector, the fixing seat and the liquid injection nozzle assembly are respectively connected to the connector, and the connector is capable of moving the liquid injection nozzle assembly toward the liquid injection port on the battery.
[0047] This makes it easier to move the injection nozzle assembly toward the injection port so that the battery can be injected with electrolyte.
[0048] In some embodiments, the connecting seat includes a first fixing plate, a second fixing plate, and a telescopic rod;
[0049] The fixing base is fixed to the first fixing plate, the injection nozzle assembly is fixed to the second fixing plate, and the telescopic rod is configured to connect the first fixing plate and the second fixing plate.
[0050] In some embodiments, the liquid injection device further includes a pressure detection module connected to the clamp and configured to detect the clamping force applied by the clamp to the large surface of the battery.
[0051] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, specific embodiments of this application are given below. Attached Figure Description
[0052] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the embodiments described below. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:
[0053] Figure 1 This is a schematic diagram of the liquid injection method provided in some embodiments of this application;
[0054] Figure 2 This application provides schematic diagrams of a single injection process for some embodiments;
[0055] Figure 3 This is a schematic diagram of a secondary injection process provided in some embodiments of this application;
[0056] Figure 4 This is a schematic diagram of the liquid injection device structure provided in some embodiments of this application;
[0057] Figure 5 for Figure 4 A partial schematic diagram;
[0058] Figure 6 This is a schematic diagram showing the clamp holding the battery according to some embodiments of this application.
[0059] The reference numerals in the detailed embodiments are as follows:
[0060] 10. Battery; 11. Clamp; 111. Fixing base; 112. First clamping arm; 113. Second clamping arm; 12. Injection nozzle assembly; 13. Connecting base; 131. First fixing plate; 132. Second fixing plate; 133. Telescopic rod; 14. Injection cup; 15. Exhaust port. Detailed Implementation
[0061] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.
[0062] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.
[0063] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0064] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0065] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.
[0066] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).
[0067] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0068] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; 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; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0069] For lithium batteries with flexible casings, the internal gas is divided into gas in the residual space and gas in the pores of the bare cell. The former gas is mainly discharged by negative pressure, while the latter gas is mainly discharged by the electrolyte wetting and exchanging space.
[0070] However, the negative pressure device in the related technology cannot effectively expel the gas inside the battery during use.
[0071] Based on the above considerations, in order to solve the problem that the negative pressure device cannot effectively expel the gas inside the battery cell during use, this application proposes a liquid injection method, which includes the following steps: fixing the large surface of the battery in a fixture and applying a squeezing force to the first area of the large surface of the battery; expelling the gas inside the battery by squeezing with the fixture using negative pressure suction; injecting electrolyte into the battery once and completing the formation; after the formation is completed, continuing to apply a squeezing force to the first area of the large surface of the battery during the second liquid injection; expelling the gas inside the electrode by squeezing with the fixture using negative pressure suction and causing some of the electrolyte inside the electrode to be squeezed out to become free electrolyte; injecting a second electrolyte into the battery, and after the second electrolyte and the free electrolyte are convectively mixed, canceling the corresponding squeezing force.
[0072] In the technical solution of this application embodiment, during the first injection of electrolyte, the first area of the flexible shell on the battery deforms under the action of extrusion force, and the gas inside the battery exchanges with the primary electrolyte. The gas is discharged outward, reserving space for electrolyte wetting, thereby improving the electrolyte wetting speed. When the electrolyte is injected for the second time, the battery continues to be subjected to extrusion force, and the gas and part of the electrolyte inside the electrode are squeezed out. At this time, the squeezed-out free electrolyte will be fully mixed with the secondary electrolyte after convection to complete the injection. After the injection is completed, the flexible shell returns to its initial state. In the overall process, by applying extrusion force to the large first area of the flexible shell on the battery in combination with negative pressure suction, the gas inside the battery can be effectively discharged, thereby improving the wetting efficiency.
[0073] According to some embodiments of this application, such as Figure 1 As shown, this application provides a liquid injection method, which includes the following steps:
[0074] Step 110: Fix the large surface of the battery in the fixture and apply compressive force to the first area of the large surface of the battery;
[0075] Step 120: Expel the gas inside the battery by using negative pressure suction and clamps to squeeze it out;
[0076] Step 130: Inject electrolyte into the battery once and complete the formation process;
[0077] Step 140: After formation is completed, during the second liquid injection, continue to apply pressure to the first area of the large surface of the battery;
[0078] Step 150: The gas inside the electrode is discharged by negative pressure suction combined with the squeezing force of the clamp, and some of the electrolyte inside the electrode is squeezed out to become free electrolyte;
[0079] Step 160: Inject secondary electrolyte into the battery. After the secondary electrolyte and free electrolyte are mixed by convection, remove the corresponding squeezing pressure.
[0080] In this embodiment, the large surface of the battery refers to the two opposite surfaces with the largest area in the external structure of the battery cell. The first region refers to the region corresponding to the internal electrode of the battery, which is not limited here.
[0081] In the technical solution of this application embodiment, during the first injection of electrolyte, the first area of the flexible shell on the battery deforms under the action of extrusion force, and the gas inside the battery exchanges with the primary electrolyte. The gas is discharged outward, reserving space for electrolyte wetting, thereby improving the electrolyte wetting speed. When the electrolyte is injected for the second time, the battery continues to be subjected to extrusion force, and the gas and part of the electrolyte inside the electrode are squeezed out. At this time, the squeezed-out free electrolyte will be fully mixed with the secondary electrolyte after convection to complete the injection. After the injection is completed, the flexible shell returns to its initial state. In the overall process, by applying extrusion force to the large first area of the flexible shell on the battery in combination with negative pressure suction, the gas inside the battery can be effectively discharged, thereby improving the wetting efficiency.
[0082] According to some embodiments of this application, such as Figure 2 As shown, injecting electrolyte into the battery includes:
[0083] Connect the liquid injection cup 14 to the liquid injection port of the battery 10, and inject electrolyte into the liquid injection cup 14 once;
[0084] The clamp 11 continuously applies compressive force;
[0085] After the electrolyte reaches the specified amount, the electrolyte valve is opened and the primary electrolyte is injected into the battery 10 through high pressure.
[0086] Repeatedly use negative pressure suction and clamp 11 to squeeze out the gas inside the battery 10 until the gas inside the battery 10 is completely discharged.
[0087] In this embodiment, "the amount of primary electrolyte in the injection cup 14 reaches the specified amount" means that the content of primary electrolyte in the injection cup 14 reaches the amount that the battery needs to inject.
[0088] In this embodiment, electrolyte is injected into the battery under high pressure, and the gas inside the battery is expelled by repeated negative pressure pumping and clamping. This can effectively remove the gas inside the battery.
[0089] According to some embodiments of this application, the clamp continuously applies compressive force, including:
[0090] The clamp 11 applies a compressive force to the first region of the large surface of the battery 10;
[0091] The squeezing pressure is matched with the negative pressure value at the injection port.
[0092] The first region in this embodiment can be referred to the description above, and will not be repeated here.
[0093] The negative pressure at the electrolyte filling port is designed to draw out gas from the battery, while the clamping force causes a directional indentation in the first area of the battery's surface. This facilitates the extraction of gas from the electrode pores and separator folds. Because the clamping force is matched with the corresponding negative pressure value, it further promotes the expulsion of gas from the battery, thereby reducing residual air bubbles inside the battery after electrolyte filling.
[0094] When the negative pressure is too high and the compressive force is insufficient, the battery will undergo localized deformation due to the excessive pressure difference between the inside and outside. When the compressive force is too high and the negative pressure is insufficient, the gaps between the electrodes are excessively compressed, making it difficult for the electrolyte to penetrate into the pores inside the electrodes. When the compressive force and negative pressure are matched, the battery's indentation deformation is controllable, and the gaps between the electrodes are in the optimal range for electrolyte penetration. This allows for deep wetting without repeated pumping and electrolyte injection, improving electrolyte injection efficiency.
[0095] According to some embodiments of this application, such as Figure 3 As shown, the gas inside the electrode is expelled by negative pressure suction combined with the squeezing force of the clamp, and part of the electrolyte inside the electrode is squeezed out to become free electrolyte, including:
[0096] Open the vent 15 on the battery 10, and continuously apply squeezing force through the clamp 11 to drive the battery 10 to concave inward;
[0097] Under the action of negative pressure and clamping force, the gas inside the electrode is discharged, and at the same time, part of the primary electrolyte inside the electrode is squeezed out, becoming free electrolyte.
[0098] In this way, after the first electrolyte injection, although the electrolyte has wetted the electrode, some electrolyte remains trapped in the electrode pores and separator micropores due to capillary action and adsorption. The flow and diffusion of electrolyte are restricted by the complex pore structure of the electrode and separator, resulting in an inconsistency between the composition of the free electrolyte and the electrolyte inside the electrode, affecting battery performance. By using the combined action of clamping force and negative pressure, the primary electrolyte inside the electrode is squeezed out into free electrolyte, allowing this portion of electrolyte to enter the free space of the battery cavity. At this time, the injected secondary electrolyte will form directional convection with the free electrolyte, which is conducive to the rapid diffusion and uniform fusion of the two electrolytes. At the same time, during the process of squeezing out the electrolyte inside the electrode, the electrode pores will undergo expansion and contraction deformation, and the tiny air bubbles trapped in the electrolyte will be squeezed out simultaneously. After entering the free space, they will be quickly drawn away by the negative pressure. Meanwhile, the flow of free electrolyte will also carry air bubbles towards the exhaust port, achieving deep gas removal.
[0099] According to some embodiments of this application, a secondary electrolyte is injected into the battery, and after the secondary electrolyte and free electrolyte are convectively mixed, the corresponding squeezing pressure is released, including:
[0100] Connect the liquid injection cup 14 to the liquid injection port on the battery 10, and inject a specified amount of secondary electrolyte into the liquid injection cup 14;
[0101] The secondary electrolyte is injected into the battery through high voltage;
[0102] After the secondary electrolyte and the free electrolyte are convectively mixed, the corresponding extrusion pressure is removed.
[0103] In this way, high pressure is used to inject the secondary electrolyte into the battery, directly driving the free electrolyte to form forced convection, breaking the limitations of molecular diffusion, and allowing the two electrolytes to fully fuse in a very short time. This ensures that the solute concentration of the mixed electrolyte is consistent throughout the entire battery. Moreover, the high-pressure injected secondary electrolyte carries the mixed electrolyte to apply directional pressure to the wetting blind area, forcing it to penetrate into the deep pores of the electrode and the micropores of the separator, filling the defects of the primary wetting, achieving full coating of the active material of the electrode, and improving the utilization rate of the active material. Because the clamp still applies extrusion pressure to the large surface of the battery during secondary injection, the internal pressure of the battery cavity is higher than the atmospheric pressure. The pressure value of the high-pressure injection can match the cavity pressure generated by the clamp extrusion, ensuring that the secondary electrolyte can be injected into the battery stably and quantitatively, avoiding insufficient or excessive injection. Meanwhile, the high-pressure injected electrolyte flows faster, and the high-pressure environment causes the gas dissolved in the electrolyte to be quickly released and float to the exhaust port area. Combined with the negative pressure suction, these gases can be discharged from the battery in time, avoiding bubbles from being trapped between the electrode and the separator, and reducing the risk of gas expansion in subsequent battery cycles.
[0104] This application also provides a liquid injection device, such as... Figure 4 As shown, the liquid injection device includes a clamp 11, a drive unit, a liquid injection nozzle assembly 12, a negative pressure suction unit, a primary liquid injection unit, and a secondary liquid injection unit. The clamp 11 is configured to hold the first area of the large surface of the battery 10, and the drive unit drives the clamp 11 to apply pressure to the first area of the large surface of the battery 10. The negative pressure suction unit is configured to evacuate air from the battery 10. The primary liquid injection unit is configured to inject primary electrolyte into the battery 10 through the liquid injection nozzle assembly 12 and complete the formation. The secondary liquid injection unit is configured to inject secondary electrolyte into the battery 10 through the liquid injection nozzle assembly 12.
[0105] The first region in this embodiment can be referred to the description above, and is not limited here.
[0106] The driving component in this embodiment can be a cylinder, an electric telescopic rod, etc., and is not limited here.
[0107] In this embodiment, the injection nozzle assembly 12 may include an injection nozzle body, a negative pressure pipeline interface, and an electrolyte pipeline interface. The negative pressure pipeline interface is used to connect an external vacuum pump, and the electrolyte pipeline interface is used to connect an external electrolyte storage device. It is understood that the injection nozzle assembly 12 may also include other components, such as a pressure gauge, but this is not limited to these components.
[0108] In this embodiment, the negative pressure suction device can be a negative pressure pump, and the primary liquid injection device and the secondary liquid injection device can all be liquid injection cups. Liquid injection is completed by inserting the liquid injection cup into the liquid injection port on the battery and then pouring electrolyte into the liquid injection cup.
[0109] During use, when the electrolyte is injected for the first time, the clamp 11 is moved by the drive component so that the clamp 11 can be adjusted to apply pressure to the first area of the large surface of the battery 10. At the same time, the negative pressure suction component is used to evacuate the battery, and the gas inside the battery and the primary electrolyte are exchanged. The gas is discharged to the outside, leaving space for the electrolyte to soak in, thereby improving the soaking speed of the electrolyte.
[0110] During the second electrolyte injection, the battery is continuously subjected to compressive force, causing gas and some electrolyte to be squeezed out from the electrodes. At this time, the squeezed-out free electrolyte mixes thoroughly with the secondary electrolyte after convection, completing the injection process. After injection, the flexible casing returns to its initial state. The entire process, by applying compressive force to the first large area of the flexible casing on the battery in conjunction with negative pressure suction, effectively removes gas from the battery, thereby improving the wetting efficiency.
[0111] According to some embodiments of this application, such as Figure 4 and combined Figure 5 , Figure 6 As shown, the clamp 11 includes a fixed base 111, a first clamping arm 112 and a second clamping arm 113, the first clamping arm 112 and / or the second clamping arm 113 being slidably connected to the fixed base 111; at the same time, the driving member cooperates with the first clamping arm 112 and the second clamping arm 113 and is configured to drive the first clamping arm 112 and the second clamping arm 113 to move closer or further away from each other.
[0112] In this embodiment, the first clamping arm 112 and the second clamping arm 113 can be connected to the fixed base 111 through the cooperation structure of the slider and the groove, which is not limited here.
[0113] Meanwhile, the driving component can be connected only to the first clamping arm 112, or the driving component can be connected only to the second clamping arm 113. When the battery 10 is located between the first clamping arm 112 and the second clamping arm 113, the squeezing force on the large surface of the battery 10 can be adjusted by driving the first clamping arm 112 and the second clamping arm 113 to move closer to each other.
[0114] According to some embodiments of this application, a first pad is provided on the side of the first clamping arm 112 facing the second clamping arm 113, and a second pad is provided on the side of the second clamping arm 113 facing the first clamping arm 112.
[0115] The first pad and the second pad are respectively matched with the first region.
[0116] In this embodiment, the size of the first pad and the size of the second pad are the same as the size of the first region.
[0117] In use, since the first pad and the second pad are respectively matched with the first region, when the first clamping arm 112 and the second clamping arm 113 are close to each other, the first pad and the second pad can be used to apply a compressive force to the designated first region.
[0118] According to some embodiments of this application, a flexible layer is provided on the side of the first pad facing the second pad and on the side of the second pad facing the first pad.
[0119] The flexible layer in this embodiment can be a silicone layer, a rubber layer, etc., and is not limited here.
[0120] During use, by setting corresponding flexible layers on the first and second pads, damage to the battery surface can be avoided when the first and second pads clamp the corresponding first area.
[0121] According to some embodiments of this application, such as Figure 4 As shown, the liquid injection device also includes a connecting seat 13, a fixing seat 111 and a liquid injection nozzle assembly 12 respectively connected to the connecting seat 13, and the connecting seat 13 can drive the liquid injection nozzle assembly 12 to move toward the liquid injection port on the battery.
[0122] In this embodiment, the fixing seat 111 and the liquid injection nozzle assembly 12 can be snapped onto the connecting seat 13. During liquid injection, the connecting seat 13 drives the corresponding liquid injection nozzle assembly 12 to fit tightly against the liquid injection port on the battery 10, thereby facilitating liquid injection into the battery 10.
[0123] According to some embodiments of this application, such as Figure 4 As shown, the connecting seat 13 includes a first fixing plate 131, a second fixing plate 132, and a telescopic rod 133; wherein, the fixing seat 111 is fixed to the first fixing plate 131, the injection nozzle assembly 12 is fixed to the second fixing plate 132, and the telescopic rod 133 is configured to connect the first fixing plate 131 and the second fixing plate 132.
[0124] In this embodiment, the telescopic rod 133 can be an electric telescopic rod, a threaded rod, etc., and is not limited here.
[0125] In this embodiment, as Figure 4As shown, the fixing seat 111 can be snapped onto the side of the first fixing plate 131 facing the second fixing plate 132, and the injection nozzle assembly 12 can be snapped onto the side of the second fixing plate 132 facing the first fixing plate 131.
[0126] By adjusting the length of the telescopic rod 133, the second fixing plate 132 and the first fixing plate 131 can be brought closer to each other, thereby facilitating the corresponding liquid injection nozzle assembly 12 to be tightly attached to the liquid injection port on the battery 10, thus making it convenient to inject liquid into the battery 10.
[0127] According to some embodiments of this application, the liquid injection device further includes a pressure detection module connected to the clamp 11 and configured to detect the clamping force applied by the clamp 11 to the large surface of the battery 10.
[0128] In this embodiment, the pressure detection module can be a pressure sensor. The pressure detection module detects the clamping force applied to the large surface of the battery 10 so that excessive pressure will cause damage to the large surface of the battery 10.
[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and they should all be covered within the scope of the claims and specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.
Claims
1. A method for injecting liquid, characterized in that, The method includes the following steps: The large surface of the battery is fixed in the fixture, and a compressive force is applied to the first area of the large surface of the battery. The gas inside the battery is expelled by using negative pressure suction and clamps to squeeze it out; After injecting electrolyte into the battery once, the formation process is completed. After formation is completed, during the second liquid injection, a squeezing pressure is continued to be applied to the first area of the large surface of the battery. The gas inside the electrode is discharged by negative pressure suction combined with the squeezing force of the clamp, and some of the electrolyte inside the electrode is squeezed out to become free electrolyte. Secondary electrolyte is injected into the battery. After the secondary electrolyte and free electrolyte are mixed by convection, the corresponding squeezing pressure is removed.
2. The injection method according to claim 1, characterized in that, The process of injecting electrolyte into the battery includes: Connect the electrolyte filling cup to the battery filling port, and inject electrolyte into the electrolyte filling cup. The clamp continuously applies compressive force; After the primary electrolyte reaches the specified amount, the electrolyte valve is opened and the primary electrolyte is injected into the battery through high pressure. Repeatedly use negative pressure suction and clamps to squeeze out the gas inside the battery until all the gas inside the battery is expelled.
3. The injection method according to claim 2, characterized in that, The clamp continuously applies compressive force, including: The clamp applies compressive force to the first area of the large surface of the battery; The extrusion pressure is matched with the negative pressure value at the injection port.
4. The injection method according to claim 1, characterized in that, The process of expelling gas from the electrode through negative pressure extraction combined with clamping force and causing some of the electrolyte within the electrode to be squeezed out as free electrolyte includes: Open the battery vent and continuously apply compressive force through the clamp to drive the battery surface to indent inward. Under the action of negative pressure and clamping force, the gas inside the electrode is discharged, and at the same time, part of the primary electrolyte inside the electrode is squeezed out, becoming free electrolyte.
5. The injection method according to claim 1, characterized in that, The process of injecting secondary electrolyte into the battery, and then releasing the corresponding squeezing pressure after the secondary electrolyte and free electrolyte have been convectively mixed, includes: Connect the injection cup to the battery injection port, and inject a specified amount of secondary electrolyte into the injection cup; The secondary electrolyte is injected into the battery under high voltage. After the secondary electrolyte and the free electrolyte are convectively mixed, the corresponding extrusion pressure is removed.