Pressing mechanism, liquid injection device and battery production system

Abstract

The utility model relates to a pressing mechanism, a liquid injection device and a battery production system. The pressing mechanism comprises a base, a pressure source and a plurality of pressing plates arranged on the base, the plurality of pressing plates comprise movable pressing plates, the movable pressing plates are movably arranged, and the movable pressing plates and the adjacent pressing plates are spaced in the moving direction of the movable pressing plates to form positioning spaces for positioning the battery cells. Wherein the pressure source can execute pressing operation, and when the pressing operation is executed, the pressure source is used for driving all the movable pressing plates to move to a target position where the width of each positioning space is consistent with the thickness of a target battery cell, so that the battery cell located in the positioning space is extruded, and the battery cell is exhausted and deformed to the target battery cell thickness. According to the technical scheme, the pressing mechanism not only can adapt to the battery cells with various thickness specifications, but also can help the battery cells to exhaust and help the expanded shell of the battery cells to recover to the normal thickness, so that three purposes are achieved, the percent of pass of the battery cells can be greatly improved, and the production line cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of battery preparation, and in particular to a pressing mechanism, a liquid injection device and a battery production system. Background Art

[0002] After the battery cell undergoes formation and aging, it often needs a second injection. During the formation and aging stages, gas will be generated inside the battery cell, and the battery cell shell will easily expand and deform outward under the pressure of the internal gas. During the secondary injection, the gas inside the battery cell is usually only exhausted by vacuuming before injection. This method of exhaust often cannot restore the normal thickness of the shell that has expanded outward, resulting in unqualified batteries. In addition, the positioning tooling used for positioning the battery cell used in the existing secondary injection is often fixed, and needs to be replaced when the production line product changes, which increases costs. Utility Model Content

[0003] Based on this, it is necessary to provide a clamping mechanism, a liquid injection device and a battery production system to address the problem that the battery cell shell cannot return to normal thickness after expansion, resulting in unqualified battery cells, and the positioning tooling cannot adapt to production line changes, which increases costs.

[0004] A clamping mechanism can be used in the secondary liquid injection stage of a battery cell, the clamping mechanism comprising:

[0005] Base;

[0006] stressors; and

[0007] A plurality of pressing plates arranged on the base, wherein the plurality of pressing plates include a movable pressing plate, the movable pressing plate is movably arranged, and the movable pressing plate is spaced apart from the adjacent pressing plates in the moving direction thereof to form a positioning space for positioning the battery cell;

[0008] Wherein, the pressure source is capable of performing a pressing operation; when performing the pressing operation, the pressure source is used to drive all the movable pressure plates to move to a target position so that the width of each positioning space is consistent with the target battery cell thickness, so as to squeeze the battery cell located in the positioning space to exhaust it and deform it to the target battery cell thickness.

[0009] In some embodiments, all the pressure plates are arranged in sequence along the first direction, a positioning space for positioning the battery cell is formed between each adjacent pressure plate, and at least one of every two adjacent pressure plates is the movable pressure plate and is movably arranged along the first direction.

[0010] In some embodiments, all of the pressing plates include two end pressing plates and at least one middle pressing plate, the two end pressing plates are respectively located at the head and tail ends of all of the pressing plates in the first direction; all of the middle pressing plates are located between the two end pressing plates;

[0011] The middle pressing plate and at least one of the end pressing plates are configured as the movable pressing plates, and the pressure source is connected to the end pressing plate serving as the movable pressing plate.

[0012] In some embodiments, one of the end pressure plates is configured as the movable pressure plate, and the other end pressure plate is fixedly disposed on the base.

[0013] In some embodiments, a slide rail extending along the first direction is disposed on the base, and a pulley is disposed on the movable pressure plate, and the pulley is movably disposed along the slide rail.

[0014] In some embodiments, the clamping mechanism further includes an elastic member, and the elastic member is connected between two adjacent pressing plates forming the positioning space;

[0015] The elastic member is used to provide an elastic force for urging the two connected pressing plates to move away from each other along a spacing direction.

[0016] In some embodiments, the clamping mechanism further includes a distance measuring sensor for acquiring distance information capable of determining the width of the positioning space;

[0017] The distance measuring sensor is in communication connection with the pressure source, and the pressure source is used to control the movement of the movable pressure plate according to the distance information fed back by the distance measuring sensor.

[0018] A liquid injection device can be used in the secondary liquid injection stage of a battery cell, the liquid injection device comprising:

[0019] The clamping mechanism as described in the above embodiment;

[0020] The nail plugging and pulling mechanism is capable of performing nail pulling and nail plugging operations on the battery cell located in the positioning space; the pressure source is used to perform the pressing operation on the battery cell located in the positioning space and subjected to the nail pulling operation; and

[0021] The liquid injection mechanism is used to perform the liquid injection operation on the battery cell that is subjected to the compaction operation, and when the liquid injection mechanism performs the liquid injection operation, the pressure source can keep all the movable pressing plates at the target position.

[0022] In some embodiments, the liquid injection device further includes a negative pressure mechanism, and the negative pressure mechanism is used to perform a vacuum operation on the battery cell located in the positioning space when the pressure source performs the pressing operation.

[0023] A battery production system, characterized by comprising the liquid injection device described in the above embodiment.

[0024] When the clamping mechanism, injection device and battery production system are used for secondary injection, the clamping mechanism can change the size of the positioning space by adjusting the position of its movable pressing plate, so that it can adapt to various specifications of battery cell thickness to adapt to production line changes. Moreover, the pressure source can also drive the movable pressing plate to move and squeeze the battery cell in the positioning space to help the battery cell exhaust until the movable pressing plate moves to the width of the positioning space consistent with the target battery cell thickness, so that the expanded shell of the battery cell returns to normal thickness. In this way, the clamping mechanism can not only adapt to battery cells of various thickness specifications, but also help the battery cell exhaust and help the expanded shell of the battery cell return to normal thickness. "One thing, three uses" can greatly improve the qualified rate of the battery cell and reduce the production line cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0026] Figure 1 Schematic diagram of the use of the clamping mechanism in some embodiments of the present application.

[0027] Figure 2 for Figure 1 A schematic diagram of a portion of the structure shown.

[0028] Figure 3 Schematic diagram of the use of the clamping mechanism in other embodiments of the present application.

[0029] The reference numerals in the specific implementation manner are as follows:

[0030] 10. Clamping mechanism; 11. Base; 11a. Slide rail; m. Supporting surface; 12. Pressing plate; k. Positioning space; 12a. Moving pressing plate; 12b. End pressing plate; 12c. Intermediate pressing plate; 13. Pulley; F. First direction; 14. Pressure source; 15. Elastic member; 16. Distance measuring sensor; 17. Boss; 20. Battery cell. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0032] In the description of the present application, it should be understood that terms such as “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “clockwise”, “counterclockwise”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships, if any, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0033] In addition, if present, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0034] In this application, unless otherwise clearly specified and limited, if any, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0035] In the present application, if it appears, unless otherwise clearly specified and limited, a first feature “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature “above”, “above” and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature “below”, “below” and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0036] It should be noted that, if present, when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be a central element. When an element is considered to be "connected to" another element, it may be directly connected to the other element or there may be a central element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and are not intended to be the only implementation method.

[0037] In view of the problem pointed out in the background art that during the secondary liquid injection, the expanded battery cell shell often cannot be restored to its normal thickness, resulting in unqualified batteries, and the positioning tooling cannot adapt to the production line change and increase costs, this application proposes a clamping mechanism that can solve these two problems at the same time. The clamping mechanism is mainly but not limited to the secondary liquid injection stage of the battery cell.

[0038] The battery cells involved in the embodiments of the present application may be cylindrical, flat, rectangular or other shapes. The battery cell usually includes a shell, an electrode assembly accommodated between the shells and an electrolyte disposed in the shell. The electrolyte can be solid or liquid. The electrode assembly is the smallest unit for electrochemical reaction in the battery, which realizes the charging and discharging of the battery cell, and usually includes a positive electrode sheet, a negative electrode sheet and a separator separating the positive electrode sheet and the negative electrode sheet. The battery cell usually also includes poles (positive poles and negative poles) for connecting the battery cell to an external circuit.

[0039] The clamping mechanism 10 of the embodiment of the present application is described in detail below.

[0040] Please refer to Figure 1 , Figure 2 and Figure 3 The clamping mechanism 10 of the embodiment of the present application can be used in the secondary liquid injection stage of the battery cell 20. The clamping mechanism 10 includes a base 11, a pressure source 14, and a plurality of pressing plates 12 arranged on the base 11. The plurality of pressing plates 12 include a movable pressing plate 12a. The movable pressing plate 12a is movably arranged. The movable pressing plate 12a and the adjacent pressing plates 12 are spaced in their moving direction to form a positioning space k for positioning the battery cell 20. Among them, the pressure source 14 can perform a clamping operation. When performing the clamping operation, the pressure source 14 is used to drive all the movable pressing plates 12a to move to a target position where the width of each positioning space k is consistent with the target battery cell thickness, so as to squeeze the battery cell 20 located in the positioning space k to exhaust it and deform it to the target battery cell thickness.

[0041] The base 11 generally has a horizontally arranged supporting surface m, and the battery cell 20 limited in the positioning space k is supported on the supporting surface m.

[0042] The movable platen 12a and the other platen 12 are adjacent and spaced apart in the moving direction of the movable platen 12a, and together form a positioning space k, and the "other platen 12" can be fixed or movable. The moving direction of the movable platen 12a is horizontal, and the thickness direction of the battery cell 20 is consistent with the moving direction of the corresponding movable platen 12a, that is, the positioning space k positions the battery cell 20 in the thickness direction, and the battery cell 20 expands roughly in the thickness direction after gas generation.

[0043] The pressure source 14 is connected to the movable platen 12a and can provide a force to the movable platen 12a to move the movable platen 12a, and the force can be a pressure or a tension. When the pressure source 14 drives the movable platen 12a to move, the width of the corresponding positioning space k can be changed. Among them, the width of the positioning space k refers to the spacing distance between the two platens 12 forming the positioning space k in the spacing direction. The spacing distance is the maximum spacing distance between the two.

[0044] In actual application, since the movable pressing plate 12 a is movable, the position of the movable pressing plate 12 a can be adjusted according to the thickness specification of the battery cell 20 , so that the width of the positioning space k is expanded or reduced, so as to facilitate the placement and positioning of the battery cell 20 .

[0045] It is understandable that the pressure source 14 can perform a pressing operation. When performing the pressing operation, the pressure source 14 can drive the movable pressing plate 12a to move to reduce the width of the positioning space k. The means for expanding the width of the positioning space k can be achieved by the pressure source 14 or by other means, such as manual pushing, which is not specifically limited.

[0046] When the pressure source 14 performs the pressing operation, it drives the movable pressing plate 12a to move and reduce the width of the positioning space k. When the width of the positioning space k is reduced to squeeze the battery cell 20, the gas inside the battery cell 20 is discharged, and at the same time, the shell of the battery cell 20 that expands outward is squeezed and deformed toward a normal thickness.

[0047] When the width of each positioning space k is reduced to the target cell thickness, all the movable pressing plates 12a are located at the target position. At this time, under the limitation of the positioning space k, the cell 20 in the positioning space k is deformed to the target cell thickness consistent with the width of the positioning space k, and the target cell thickness is usually the normal thickness required for the cell 20. Different types of cells 20 may have different target cell thicknesses.

[0048] When the clamping mechanism 10 is applied to secondary liquid injection, the clamping mechanism 10 can change the size of the positioning space k by adjusting the position of the movable pressing plate 12a, so as to adapt to the thickness of the battery cells 20 of various specifications, so as to adapt to the production line change. Moreover, the pressure source 14 can also drive the movable pressing plate 12a to move and squeeze the battery cells 20 in the positioning space k, and help the battery cells 20 to exhaust, until the movable pressing plate 12a moves to the width of the positioning space k consistent with the target battery cell thickness, so that the expanded shell of the battery cell 20 returns to normal thickness.

[0049] In this way, the clamping mechanism 10 can not only adapt to battery cells 20 of various thickness specifications, but also help the battery cells 20 to exhaust and help the expanded shell of the battery cells 20 to return to normal thickness. This "one thing, three uses" can greatly improve the pass rate of the battery cells 20 and reduce production line costs.

[0050] It should be noted that the positioning surface of the pressing plate 12 forming the positioning space k is adapted to the contour surface of the battery cell 20 shell under normal thickness. The positioning surface is in contact with the outer wall surface of the shell of the battery cell 20, and can also regularize the flatness of the shell. When the positioning surface of the pressing plate 12 is a plane, the clamping mechanism 10 is adapted to the square battery cell 20. When the positioning surface of the pressing plate 12 is an arc surface, the clamping mechanism 10 is adapted to the cylindrical battery cell 20.

[0051] Specifically, in some embodiments, the positioning surface of the pressing plate 12 is a plane. In this case, the pressing mechanism 10 is adapted to the positioning of the square battery cell 20 in the secondary liquid injection stage.

[0052] In some embodiments, reference Figure 1 , Figure 2 and Figure 3 All the pressing plates 12 are arranged in sequence along the first direction F, and a positioning space k for positioning the battery cell 20 is formed between each adjacent pressing plate 12. At least one of every two adjacent pressing plates 12 is a movable pressing plate 12a, and is movably arranged along the first direction F.

[0053] The pressure source 14 can be connected to each movable platen 12a to jointly drive each movable platen 12a to move independently. The pressure source 14 can also be connected to only one movable platen 12a, and drive all movable platens 12a to move through the force transmission of the movable platen 12a and the battery cell 20. The specific connection between the pressure source 14 and the movable platen 12a can be adaptively designed according to the setting scheme of the movable platen 12a.

[0054] At this time, all the pressing plates 12 are arranged in sequence and at intervals in the first direction F, that is, each pressing plate 12 can participate in forming two positioning spaces k. In this way, the pressing mechanism 10 can press and position a large number of battery cells 20 each time, and the utilization rate of the pressing mechanism 10 is high. In addition, all the moving mechanisms move in the same direction, which can simplify the structure of the pressure source 14.

[0055] There are many specific configurations of the pressure source 14, and those skilled in the art can make conventional configurations. As an example, the pressure source 14 includes a push cylinder and a transmission rod, and the transmission rod can be connected to at least one movable platen 12a, and under the push of the push cylinder, the at least one movable platen 12a is moved in the first direction F.

[0056] It is understandable that in other embodiments, the moving directions of the movable pressing plates 12 a may be different, as long as the battery cells 20 can be pressed and squeezed.

[0057] In some embodiments, reference Figure 1 , Figure 2 and Figure 3 All the pressing plates 12 include two end pressing plates 12b and at least one middle pressing plate 12c. The two end pressing plates 12b are respectively located at the head and tail ends of all the pressing plates 12 in the first direction F, and all the middle pressing plates 12c are located between the two end pressing plates 12b. The middle pressing plate 12c and at least one end pressing plate 12b are configured as a moving pressing plate 12a, and the pressure source 14 is connected to the end pressing plate 12b as the moving pressing plate 12a.

[0058] When the battery cells 20 are placed in the positioning spaces k between the adjacent pressure plates 12, the pressure source 14 pushes the end pressure plate 12b to move, and the force is transmitted through the battery cells 20, so that the remaining intermediate pressure plates 12c move. In this way, the structure of the clamping mechanism 10 can be greatly simplified, and the configuration cost of the pressure source 14 can be reduced.

[0059] Specifically in some embodiments, one end pressing plate 12 b is configured as a movable pressing plate 12 a , and the other end pressing plate 12 b is fixedly disposed on the base 11 .

[0060] The end pressure plate 12b fixed on the base 11 can be arranged on the base 11 by welding, fastening connection, etc. At this time, the pressing mechanism 10 only needs to be equipped with a pressure source 14 at one end, which can reduce the number of pressure sources 14 and reduce costs.

[0061] Of course, in other embodiments, both end pressure plates 12 b may be constructed as movable pressure plates 12 a , and then independent pressure sources 14 may be provided for the two corresponding pressure plates 12 .

[0062] In some embodiments, reference Figure 1 and Figure 2 A slide rail 11a extending along the first direction F is provided on the base 11, the slide rail 11a is provided on the movable pressing plate 12a, and the pulley 13 is movably provided along the slide rail 11a.

[0063] Specifically, the slide rail 11a can be a slide groove recessed on the supporting surface m, and the pulley 13 can be rotatably inserted in the slide groove. At this time, the movable pressing plate 12a is rotatably arranged on the base 11, and the movable pressing plate 12a moves more smoothly and labor-savingly, which can reduce the energy consumption of the pressure source 14.

[0064] In addition, two parallel slide rails 11a can be set on the base 11, and pulleys 13 are set on both sides of the bottom of the movable pressure plate 12a. Each pulley 13 is correspondingly set on a slide rail 11a, and the battery cell 20 is supported on the supporting surface m located between the two slide rails 11a.

[0065] In some embodiments, reference Figure 3 The clamping mechanism 10 further includes an elastic member 15, and the elastic member 15 is connected between two adjacent pressing plates 12 forming the positioning space k. The elastic member 15 is used to provide an elastic force to force the two connected pressing plates 12 to move away from each other along the spacing direction.

[0066] Specifically, an elastic member 15 is disposed between each two adjacent pressing plates 12. The elastic member 15 may be a spring, etc. The elastic member 15 may be located in the positioning space k or outside the positioning space k, and its specific arrangement position is not limited.

[0067] When the pressure source 14 performs the pressing operation, the distance between adjacent pressing plates 12 becomes smaller, and the elastic member 15 is compressed. When it is no longer necessary to position and press the battery cell 20, the pressure source 14 cancels its force, and the distance between the pressing plates 12 becomes larger under the restoring force of the elastic member 15. In this way, the setting of the elastic member 15 facilitates each pressing plate 12 to return to its initial position.

[0068] Specifically in one embodiment, refer to Figure 3 A convex column 17 is provided on the side of the pressing plate 12 , and the elastic member 15 is connected to the convex column 17 of each pressing plate 12 .

[0069] In some embodiments, reference Figure 3 The clamping mechanism 10 further includes a distance sensor 16, which is used to obtain distance information that can determine the width of the positioning space k. The distance sensor 16 is in communication with the pressure source 14, and the pressure source 14 is used to control the movement of the movable pressing plate 12a according to the distance information fed back by the distance sensor 16.

[0070] The distance sensor 16 may be, but is not limited to, arranged on the base 11 or the pressure source 14. The distance sensor 16 may be a visual distance sensor 16, an ultrasonic distance sensor 16, a laser distance sensor 16, a piezoelectric distance sensor 16, etc. The distance information obtained by the distance sensor 16 may be the moving distance of the driving end of the pressure source 14. The moving distance of the moving plate 12a is determined according to the moving distance of the driving end of the pressure source 14, and then the width of the positioning space k is determined. In this case, the distance sensor 16 may be a laser distance sensor 16 arranged on the pressure source 14, etc. The distance information obtained by the distance sensor 16 may also be directly the distance information representing the width of the positioning space k. For example, the image information of all the pressing plates 12 is obtained by the visual distance sensor 16, and the width of the positioning space k is directly fed back according to the image information. In this case, the distance sensor 16 may be arranged on the base 11. Regarding the setting method and specific selection of the distance sensor 16, those skilled in the art may make conventional settings.

[0071] The pressure source 14 is connected to the distance sensor 16 for communication. The pressure source 14 can determine whether the movable platen 12a has moved into position according to the distance information fed back by the distance sensor 16. Specifically, the pressure source 14 determines the width of the positioning space k according to the distance information fed back by the distance sensor 16. When the width of the positioning space k reaches the target cell thickness, it indicates that the movable platen 12a has moved into position. In this way, the pressure source 14 can accurately control the movement of the movable platen 12a based on the distance information fed back by the distance sensor 16, thereby achieving a good degree of recovery of the shell of the cell 20.

[0072] Specifically in one embodiment, refer to Figure 3 , a plurality of pressure plates 12 are arranged in sequence along the first direction F, wherein one end pressure plate 12b serves as a movable pressure plate 12a, and the other end pressure plate 12b is fixedly arranged, and the pressure source 14 is connected to the end pressure plate 12b serving as the movable pressure plate 12a. The distance measuring sensor 16 is arranged on the base 11, and is used to measure the distance between itself and the end pressure plate 12b serving as the movable pressure plate 12a. At this time, the driving distance of the pressure source 14 can be obtained by the moving distance of the end pressure plate 12b, and then the changing width of each positioning space k can be obtained according to the number of positioning spaces k (changing width = driving distance / number of positioning spaces k), and the current width of the positioning space k can be calculated based on the initial width and changing width of the positioning space k (current width = initial width - changing width).

[0073] In addition, the embodiment of the present application also provides a liquid injection device (not shown), which can be used in the secondary liquid injection stage of the battery cell 20. The liquid injection device includes the clamping mechanism 10, the plugging and pulling mechanism and the liquid injection mechanism in the above-mentioned embodiment. The plugging and pulling mechanism can perform a nail pulling operation and a nail plugging operation on the battery cell 20 located in the positioning space k. The pressure source 14 is used to perform a clamping operation on the battery cell 20 that is located in the positioning space k and is subjected to a nail pulling operation. The liquid injection mechanism is used to perform a liquid injection operation on the battery cell 20 that is subjected to a clamping operation, and when the liquid injection mechanism performs the liquid injection operation, the pressure source 14 can keep all movable pressure plates 12a in the target position.

[0074] The battery cell 20 is provided with a liquid injection port, and a sealing nail is provided at the liquid injection port. In actual application, the plugging and nail pulling mechanism removes the sealing nail at the liquid injection port of the aged battery cell 20 (i.e., performs a nail pulling operation) to open the liquid injection port. When the plugging and nail pulling mechanism performs a nail pulling operation on the battery cell 20, the battery cell 20 can be located in the positioning space k of the clamping mechanism 10, or it can be located outside the positioning space k.

[0075] The pressure source 14 performs a pressing operation on the battery cell 20 that is subjected to the nail pulling operation and is located in the positioning space k, so that the movable pressing plate 12a moves and reduces the width of the positioning space k to squeeze the battery cell 20 until the width of the positioning space k is consistent with the target battery cell thickness. In this process, the gas inside the battery cell 20 is gradually discharged outward through the liquid injection port, and the outwardly expanded shell of the battery cell 20 is gradually squeezed until it is deformed to a normal thickness.

[0076] When the shell of the battery cell 20 is at a normal thickness, the injection mechanism injects liquid into the battery cell 20. Specifically, the injection nozzle may be inserted into the injection port, and then the electrolyte is injected into the battery cell 20 through the injection nozzle. During the injection process, the pressure source 14 keeps the movable pressing plate 12a at the target position, so that the shell of the battery cell 20 is kept at a normal thickness. In this way, during the injection process, the shell is not easily deformed under the pressure of the electrolyte inside the battery cell 20, causing its thickness to change.

[0077] When the injection is completed, the plugging and pulling mechanism plugs the sealing nail back into the injection port (i.e., performs the plugging operation). Then, the pressure source 14 gradually withdraws the force. At this point, the secondary injection of the battery cell 20 is completed.

[0078] The specific structures of the plug nail extraction mechanism and the liquid injection mechanism can refer to the conventional settings in the art. Among them, the plug nail extraction mechanism can be but not limited to removing and installing sealing nails by negative pressure adsorption.

[0079] When the above-mentioned liquid injection device is used for the secondary liquid injection of the battery cell 20, the pressing mechanism 10 can be used to assist the exhaust of the battery cell 20 before the liquid injection, and the thickness of the shell of the battery cell 20 can be deformed to a normal thickness. In this way, the qualified rate of the battery cell 20 can be improved. Of course, the liquid injection device also has all the above-mentioned beneficial effects, which will not be repeated here.

[0080] In some embodiments, the liquid injection device further includes a negative pressure mechanism, which is used to perform a vacuum operation on the battery cell 20 located in the positioning space k when the pressure source 14 performs a pressing operation.

[0081] The negative pressure mechanism is used to draw negative pressure to the battery cell 20. When the pressure source 14 controls the movable pressing plate 12a to squeeze the battery cell 20, the negative pressure mechanism is turned on to speed up the exhaust of the battery cell 20 and shorten the production process.

[0082] Regarding the specific structure of the negative pressure mechanism, those skilled in the art can make conventional settings, which will not be elaborated here.

[0083] It should be noted that the clamping mechanism and the liquid injection device in the embodiment of the present application can be used not only in the secondary liquid injection stage, but also in the primary liquid injection stage. When the clamping mechanism and the liquid injection device are used in the secondary liquid injection stage, they not only have the effect of positioning the battery cell, but also have the effect of assisting exhaust and squeezing the expanded shell to a normal thickness.

[0084] In addition, an embodiment of the present application also provides a battery production system, including the above-mentioned liquid injection device.

[0085] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0086] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A clamping mechanism, which can be used in the secondary liquid filling stage of a battery cell; characterized in that: The clamping mechanism comprises: Base (11); stressors (14); and A plurality of pressing plates (12) are arranged on the base (11), the plurality of pressing plates (12) comprising a movable pressing plate (12a), the movable pressing plate (12a) being movably arranged, and the movable pressing plate (12a) and the adjacent pressing plate (12) being spaced apart in the moving direction thereof to form a positioning space (k) for positioning the battery cell; The pressure source (14) is capable of performing a pressing operation; when performing the pressing operation, the pressure source (14) is used to drive all the movable pressure plates (12a) to move to a target position where the width of each positioning space (k) is consistent with the target battery cell thickness, so as to squeeze the battery cell located in the positioning space (k) to exhaust the battery cell and deform it to the target battery cell thickness.

2. The clamping mechanism according to claim 1, characterized in that: All the pressing plates (12) are arranged in sequence along a first direction (F), a positioning space (k) for positioning the battery cell is formed between each adjacent pressing plate (12), and at least one of every two adjacent pressing plates (12) is the movable pressing plate (12a) and is movably arranged along the first direction (F).

3. The clamping mechanism according to claim 2, characterized in that: All of the pressing plates (12) include two end pressing plates (12b) and at least one middle pressing plate (12c), wherein the two end pressing plates (12b) are respectively located at the head and tail ends of all of the pressing plates (12) in the first direction (F); and all of the middle pressing plates (12c) are located between the two end pressing plates (12b); The intermediate pressure plate (12c) and at least one of the end pressure plates (12b) are constructed as the movable pressure plate (12a), and the pressure source (14) is connected to the end pressure plate (12b) serving as the movable pressure plate (12a).

4. The clamping mechanism according to claim 3, characterized in that: One of the end pressure plates (12b) is constructed as the movable pressure plate (12a), and the other end pressure plate (12b) is fixedly arranged on the base (11).

5. The clamping mechanism according to claim 2, characterized in that: The base (11) is provided with a slide rail (11a) extending along the first direction (F), and the movable pressing plate (12a) is provided with a pulley (13), and the pulley (13) is movably arranged along the slide rail (11a).

6. The clamping mechanism according to claim 1, characterized in that: The clamping mechanism further comprises an elastic member (15), and the elastic member (15) is connected between two adjacent pressing plates (12) forming the positioning space (k); The elastic member (15) is used to provide an elastic force that urges the two connected pressing plates (12) to move away from each other along a spacing direction.

7. The clamping mechanism according to claim 1, characterized in that: The clamping mechanism further comprises a distance measuring sensor (16) for acquiring distance information capable of determining the width of the positioning space (k); The distance measuring sensor (16) is communicatively connected to the pressure source (14), and the pressure source (14) is used to control the movement of the movable pressure plate (12a) according to the distance information fed back by the distance measuring sensor (16).

8. A liquid injection device, which can be used in the secondary liquid injection stage of a battery cell, characterized in that: The liquid injection device comprises: The clamping mechanism according to any one of claims 1 to 7; The nail plugging and pulling mechanism is capable of performing a nail pulling operation and a nail plugging operation on the battery cell located in the positioning space (k); the pressure source (14) is used to perform the pressing operation on the battery cell located in the positioning space (k) and subjected to the nail pulling operation; and The liquid injection mechanism is used to perform the liquid injection operation on the battery cell that is subjected to the pressing operation, and when the liquid injection mechanism performs the liquid injection operation, the pressure source (14) can keep all the movable pressing plates (12a) at the target position.

9. The liquid injection device according to claim 8, characterized in that: The liquid injection device further comprises a negative pressure mechanism, which is used to perform a vacuum operation on the battery core located in the positioning space (k) when the pressure source (14) performs the pressing operation.

10. A battery production system, characterized in that: Comprising the liquid injection device according to any one of claims 1 to 9.

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