An electrode assembly for a lithium secondary battery

Abstract

The utility model discloses a kind of electric core stacking pre-tightening device, it is related to new energy industry soft package electric core stacking technical field, to solve the problem of module pre-tightening force being limited in prior art, tab support positioning is not accurate and electric core stacking is prone to mispositioning.The device includes bracket positioning frame, limiting component, pre-tightening force device, digital display screen and bottom plate;Bracket positioning frame is accurately positioned and quickly assembled and disassembled by slide rail and buckle;Limiting component is equipped with pressure sensor, and real-time monitoring stacking pressure is cooperated with digital display screen;Pre-tightening force device adjusts pre-tightening force by rotating handle knob and guide column, and is adapted to different specifications electric core;Electric core support block ensures that stacking horizontal position is stable.The utility model is positioned by the three-dimensional positioning of bracket positioning frame, the pressure of pre-tightening force device is adjustable and limiting component is real-time monitored, solve the problem of module pre-tightening force being limited in prior art, positioning is not accurate and stacking mispositioning, and different specifications electric core module can be adapted to stacking pre-tightening.

Description

Technical Field

[0001] This utility model belongs to the field of soft-pack battery cell stacking technology in the new energy industry, and particularly relates to a battery cell stacking pre-tightening device. Background Technology

[0002] In the new energy lithium battery industry, the process of stacking soft-pack cells into modules must simultaneously meet core requirements such as precise horizontal alignment, controllable module pre-tightening force, and stable positioning of the tab bracket.

[0003] Existing technologies often suffer from the following structural design flaws:

[0004] First, the preload adjustment of the module is limited, making it impossible to dynamically adjust the preload according to different specifications of the battery cells (such as thickness and material differences). In actual production, when the battery cell size changes or needs to be adapted to different steel strip insertion processes, the battery cell is prone to deformation due to pressure overload, or the module becomes loose due to insufficient pressure, resulting in poor compatibility. Second, the positioning accuracy of the tab bracket is insufficient. During stacking, the tab bracket is easily displaced by squeezing and impact forces, which can easily lead to poor welding or short circuits in subsequent welding processes. Third, the horizontal stability of the battery cell stacking is poor. Existing technologies often use clamping plates on both sides, which can easily cause horizontal movement due to gravity or lateral forces during stacking. Especially in multi-layer stacking, the cumulative misalignment of the battery cells directly affects the overall dimensional accuracy of the module and the assembly yield. Finally, existing technologies generally have compatibility defects and cannot meet the requirements of flexible production.

[0005] Therefore, given the shortcomings of existing devices in terms of preload controllability, positioning accuracy, and compatibility, there is an urgent need to design a cell stacking preload device to solve the above-mentioned technical problems. Utility Model Content

[0006] In view of the technical problems existing in the prior art, this utility model aims to provide a cell stacking pre-tightening device that integrates positioning, support, constraint and monitoring functions.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A cell stacking pre-tightening device includes a limiting component, a pre-tightening force device, a bracket positioning frame, a base plate, and a pressure sensing and display device;

[0009] The limiting component and the pre-tightening device are sequentially disposed on the base plate along the first direction and are distributed opposite to each other.

[0010] The limiting component, the pre-tightening device, and a pair of bracket positioning frames arranged opposite each other along the second direction together constitute a cubic stacking space for stacking battery cells to form a battery cell module; the first direction is perpendicular to the second direction;

[0011] The pre-tightening device is movably mounted on the base plate and is used to push the battery cell module to move along the first direction and abut against the limiting component, so as to apply a pre-tightening force to the stacked battery cell modules.

[0012] The bracket positioning frame is slidably mounted on the base plate along a direction parallel to the second direction, and is used to drive the tab bracket to move along a direction parallel to the second direction to position and install it on the end of the cell module where the tab is located.

[0013] The pressure sensing and display device is used to receive the preload force on the battery cell module to sense and display the preload force of the battery cell module in real time.

[0014] Furthermore, the pressure sensing and display device includes a pressure sensor and a digital display screen. The digital display screen is embedded in the surface of the base plate and electrically connected to the pressure sensor embedded in the limiting component. The pressure sensor is used to withstand the pressure of the battery cell and transmit the pressure value to the digital display screen.

[0015] Furthermore, the limiting component includes a limiting fixing plate and a limiting plate. The limiting fixing plate is vertically fixed to the surface of the base plate, and the limiting plate and the limiting fixing plate are slidably connected. The pressure sensor is embedded between the limiting fixing plate and the limiting plate.

[0016] Furthermore, the limiting plate and the limiting fixing plate are slidably connected by limiting support columns. The limiting support columns are configured to be at least three, which slide in cooperation with the holes on the limiting fixing plate. The limiting support columns are evenly distributed in an array around the pressure sensor and are used to ensure that the limiting plate moves perpendicular to the base plate to ensure the uniformity of pressure on the surface of the battery cell module.

[0017] Furthermore, the pre-tightening device includes a pre-tightening fixing plate fixed above the base plate, a contact plate slidably mounted on the pre-tightening fixing plate along a direction parallel to the first direction, and a drive unit connected to the contact plate and used to drive it to reciprocate along a direction parallel to the first direction to apply a pre-tightening force to the cell module.

[0018] Furthermore, the drive unit includes: a rotary handle, a rotating shaft, and a guide post. The pre-tightening fixing plate has a threaded hole extending through it along the thickness direction. The rotating shaft partially passes through the threaded hole and has an external thread on its outer periphery that mates with the threaded hole. One end of the rotating shaft is fixedly connected to the rotary handle, and the other end abuts against the contact plate. The guide post slides through the pre-tightening fixing plate and is fixed at one end to the contact plate. By rotating the rotary handle, the contact plate moves toward the battery cell module to apply a pre-tightening force to it.

[0019] Furthermore, one end of the rotating shaft near the contact plate abuts against the contact plate via a bearing, and / or

[0020] The guide posts are configured as at least three and are evenly distributed in a circumferential array around the rotation axis to control the contact plate to move perpendicular to the base plate so as to achieve uniform pressure on the surface of the battery cell module.

[0021] Furthermore, the bracket positioning frame includes:

[0022] The support plate is slidably mounted on the base plate along a direction parallel to the second direction. It is configured as a U-shaped frame structure with a notch at the top and an inner wall with a mounting groove for accommodating the tab bracket.

[0023] The upper positioning plate is detachably connected to the support plate via a snap-fit ​​mechanism and is used to cover the notch to position the tab bracket located inside the mounting slot.

[0024] Furthermore, the mounting groove is formed at the bottom and inner walls of both sides of the support plate, and extends from the inner bottom surface of the support plate to the top notch;

[0025] The bottom mounting groove of the support plate and the side of the upper positioning plate opposite to the mounting groove are both provided with positioning holes. The positioning of the electrode bracket along the height direction is achieved by a fixing pin passing through the positioning hole.

[0026] Furthermore, the latching mechanism includes a latch and a latching interface that cooperate with each other. The latch is disposed on the support plate, and the latching interface is disposed on the upper limit plate. The latch and the latching interface engage and lock together to achieve a detachable connection between the upper limit plate and the support plate.

[0027] Furthermore, the bottom of the support plate is provided with a slide groove that is slidably connected to the slide rail fixed on the base plate. The bottom end face of the support plate is provided with positioning holes on both sides. The base plate surface on both sides of the bottom of the support plate is fixed with bracket positioning blocks parallel to the slide rail. The bracket positioning blocks have positioning holes, and fixing pins are inserted into the positioning holes. The fixing pins pass through the positioning holes to fix the bracket positioning frame at the cell stacking position.

[0028] Furthermore, a cell support block is provided between the pre-tightening device and the limiting component. The pre-tightening device, the limiting component, the cell support block, and the bracket positioning frame enclose a cubic stacking space. The thickness of the cell support block is equal to the vertical distance from the upper surface of the bottom mounting groove of the support plate to the upper surface of the base plate, which is used to support the cells and maintain the stacked horizontal position.

[0029] Furthermore, the upper limit plate has a rectangular notch at one end of the cell stack to ensure that the cells have sufficient displacement space when stacking.

[0030] The beneficial effects achieved by this utility model are as follows:

[0031] 1. Improve the controllability of preload: The preload is adjusted by turning the handle and guide column, and the pressure value is fed back in real time by the digital display screen, ensuring that the module preload is within the design range, thus solving the problem of limited preload in traditional devices.

[0032] 2. Improve positioning accuracy: The bracket positioning frame achieves three-dimensional positioning of the tab bracket through the upper limit plate, lower limit plate and fixing pin. The slide rail design facilitates the assembly and disassembly of the bracket and solves the problem of inaccurate positioning.

[0033] 3. Enhanced stacking stability: The limiting plate of the limiting component works with the cell support block to form a stable stacking space. The pressure sensor monitors the pressure in real time to prevent misalignment of the stacked cells.

[0034] 4. Achieve flexible compatibility: The detachable clips and modular design support quick component replacement and adapt to the stacking of different sized battery cells, solving the problem of poor compatibility of traditional tooling. Attached Figure Description

[0035] Figure 1 This is a three-dimensional schematic diagram of the main structure of the cell stacking pre-tightening device in Example 1.

[0036] Figure 2 This is a top view of the cell stacking state of the cell stacking pre-tightening device in Example 1.

[0037] Figure 3 This is a three-dimensional structural diagram of the bracket positioning frame of the cell stacking pre-tightening device in Example 1.

[0038] Figure 4 This is a partial three-dimensional enlarged view of the buckle and card interface connection of the bracket positioning frame of the battery cell stacking pre-tightening device in Example 1.

[0039] Figure 5 This is a three-dimensional side view of the limiting component of the cell stacking pre-tightening device in Example 1.

[0040] Figure 6 This is a three-dimensional side view of the pressure sensor exposed after removing the limiting plate from the limiting component of the cell stacking pre-tightening device in Example 1.

[0041] Figure 7 This is a three-dimensional side view of the pre-tightening force device of the cell stacking pre-tightening device in Example 1.

[0042] Figure 8 The diagram shows the bracket positioning frame of the cell stacking pre-tightening device in Example 1, which is fixed to the tab bracket by the tab bracket fixing pin.

[0043] In the diagram: 100. Cell stacking pre-tightening device; 1. Bracket positioning frame; 1-1. Upper limit plate; 1-2. Lower limit plate; 1-3. Support plate; 1-4. Slide rail; 1-5. Fixing pin; 1-6. Buckle; 1-7. Snap-in interface; 1-8. Snap ring; 1-9. Drive arm; 1-10. Movable rotating shaft; 1-11. Base rotating shaft; 1-12. Snap-in base; 1-13. Bracket positioning block; 1-14. Electrode bracket fixing pin; 2. Limiting component; 2-1. Reinforcing rib; 2- 2. Limiting and fixing plate; 2-3. Limiting plate; 2-4. Pressure sensor; 2-5. Limiting base; 2-6. Limiting support column; 3. Pre-tightening device; 3-1. Contact plate; 3-2. Pre-tightening fixing plate; 3-3. Rotating handle; 3-4. Reinforcing plate; 3-5. Guide column; 3-6. Rotating shaft; 3-7. Pre-tightening base; 4. Digital display screen; 5. Tooling plate; 6. Battery cell support block; 7. Electrode bracket; a. Cubic stacking space. Detailed Implementation

[0044] The technical solutions of the utility model embodiments will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the utility model, and not all embodiments.

[0045] Example 1

[0046] like Figure 1 , Figure 2As shown, Embodiment 1 provides a cell stacking pre-tightening device 100, including a tooling plate 5, which is a base plate and serves as the basic supporting component of the cell stacking pre-tightening device 100. A pair of bracket positioning frames 1, a limiting component 2, a pre-tightening force device 3, and a digital display screen 4 are fixed on the tooling plate 5. The limiting component 2 and the pre-tightening force device 3 are sequentially arranged on the tooling plate 5 along a first direction and are distributed opposite to each other. The limiting component 2, the pre-tightening force device 3, and the pair of bracket positioning frames 1 arranged opposite to each other along a second direction together constitute a cubic stacking space a for stacking cells to form a cell module. The first direction is perpendicular to the second direction. The pre-tightening device 3 is movably mounted on the tooling plate 5 and is used to push the battery cell module to move along the first direction and abut against the limiting component 2 to apply a pre-tightening force to the stacked battery cell modules; the bracket positioning frame 1 is slidably mounted on the slide rail 1-4 on the surface of the tooling plate 5 along the second direction and is used to drive the tab bracket to move along the second direction to position and install it at the end of the battery cell module with the tab; the digital display screen 4 is embedded in a corner of the surface of the tooling plate 5 and is electrically connected to the pressure sensor 2-4 embedded on the limiting component 2. The pressure sensor 2-4 is used to bear the battery cell pressure and transmit the pressure value to the digital display screen 4. The pre-tightening device 3 is adjustable to accommodate different specifications of battery cells. The pressure sensors 2-4 monitor the pressure in real time. Through the cubic stacking space a formed by the sliding of the slide rails 1-4 and the relatively set limit components 2 and the pre-tightening device 3, the horizontal position of the battery cells is accurately aligned, solving the problems of limited pre-tightening force, poor compatibility and easy misalignment of stacking in traditional devices, and improving the assembly accuracy and stability of the module.

[0047] The bracket positioning frame 1, as Figure 3As shown, it includes an upper positioning plate 1-1 and a support plate 1-3. The support plate 1-3 is slidably installed on the tooling plate 5 along a direction parallel to the second direction. It is configured as a U-shaped frame structure with a notch at the top and an inner wall with a mounting groove for accommodating the tab bracket. The upper positioning plate 1-1 is detachably connected to the support plate 1-3 by a snap-fit ​​mechanism and is used to cover the notch to position the tab bracket located inside the mounting groove. The mounting groove is formed at the bottom and inner walls of both sides of the support plate 1-3, and extends from the inner bottom surface of the support plate 1-3 to its top notch. The bottom mounting groove portion of the support plate 1-3 forms a lower limiting plate 1-2. The lower limiting plate 1-2 and the upper limiting plate 1-1 are provided with positioning holes on the side opposite to the mounting groove. Support positioning blocks 1-13 are provided on both sides of the support plate 1-3. The support positioning blocks 1-13 are parallel to the slide rail 1-4 and fixed to the tooling plate 5. The support positioning blocks 1-13 have positioning holes, and the fixing pins 1-5 pass through the positioning holes on the support positioning blocks 1-13. The positioning holes on the support plate 1-3 can be accessed to fix the bracket positioning frame 1 in a preset position; the bottom of the support plate 1-3 is provided with a sliding groove, which is slidably connected to the slide rail 1-4. The slide rail 1-4 is fixed to the tooling plate 5 by bolts, so that a pair of bracket positioning frames 1 can slide towards or away from each other along the slide rail 1-4, which facilitates the installation of the electrode bracket 7 and the sliding insertion of the cell module, and realizes adjustment within a range of 100mm in front and behind; the U-shaped support plate 1-3 and the detachable upper limit plate 1-1 form a U-shaped frame to realize the circumferential limit of the electrode bracket 7; the rectangular hollow position is convenient to accommodate the electrode and avoid the electrode from being deformed by pressure.

[0048] A cell support block 6 is provided between the pre-tightening device 3 and the limiting component 2 to support the cells and maintain their horizontal stacking position. The cell support block 6 consists of two long rectangular blocks, which are fixed to the surface of the tooling plate 5 and arranged parallel to each other between the pre-tightening device 3 and the limiting component 2. The thickness of the cell support block 6 is equal to the vertical distance between the upper surface of the lower limiting plate 1-2 (i.e., the upper surface of the bottom mounting groove of the support plate 1-3) and the surface of the tooling plate 5, ensuring that the cells are in a horizontal position. The cell support block 6 forms the bottom of the cubic stacking space a, which facilitates the insertion of the steel strip into the product and facilitates the stacking of the cells. The cell support block 6 is at the same height as the upper surface of the lower limiting plate 1-2, ensuring that the cells are stacked horizontally without tilting and restricting the horizontal movement of the cells. At the same time, a gap is reserved for the insertion of the steel strip to facilitate the subsequent module bundling process.

[0049] like Figure 3 , Figure 4As shown, the locking mechanism includes: a locking interface 1-7 and a buckle 1-6. The upper limit plate 1-1 and the support plate 1-3 are detachably connected via the locking interface 1-7 and the buckle 1-6. One end of the buckle 1-6 is fixed to the outer end face of the upper frame of the support plate 1-3 via a buckle base 1-12. The buckle base 1-12 is rotatably connected to the drive arm 1-9 via a base pivot 1-11. The drive arm 1-9 has a movable pivot 1-10 located below the base pivot 1-11. A retaining ring 1-8 is connected to shaft 1-10. The retaining ring 1-8 can rotate along the movable shaft 1-10. One end of the locking interface 1-7 is fixed to the end face of the upper limit plate 1-1, and a hook-shaped notch is provided at the end opposite to the upper limit plate 1-1. The hook-shaped notch engages with the retaining ring 1-8. After the retaining ring 1-8 engages with the hook-shaped notch, pressing the drive arm 1-9 can lock the retaining ring 1-8 into the locking interface 1-7, and pulling the drive arm 1-9 can disengage the retaining ring 1-8 from the locking interface 1-7, achieving quick disassembly. The locking mechanism realizes the locking and clamping function of the upper limit plate 1-1 and the support plate 1-3 through a buckle + locking interface, realizing the quick assembly and disassembly of the upper limit plate 1-1, improving the efficiency of type change and adapting to cells with different tab spacings.

[0050] like Figure 3 As shown, after the upper limit plate 1-1 and the support plate 1-3 are engaged with the buckle 1-6 via the card interface 1-7, the upper limit plate 1-1 exactly covers the upper notch of the U-shaped rectangular frame structure with a rectangular notch, forming a rectangular hollow structure together with the support plate 1-3. When stacking battery cells, the rectangular hollow structure is used to limit the position of the tab support 7, ensuring that the support is vertical, unaffected by external forces, and can accommodate the tabs of the stacked battery cells. The upper limit plate 1-1 has a rectangular notch facing the battery cell stacking part to ensure that the pre-tightening device 3 has sufficient displacement space when pre-tightening the battery cell stacking.

[0051] like Figure 8 As shown, the upper limit plate 1-1 is fixed with a downward protruding tab bracket fixing pin 1-14 to limit the positioning hole at the upper part of the tab bracket 7, and the lower limit plate 1-2 is fixed with an upward protruding tab bracket fixing pin 1-14 to limit the positioning hole at the lower part of the tab bracket 7, so as to ensure that the tab bracket 7 is assembled in an accurate position and can accurately detect the installation position of the tab bracket 7.

[0052] The limiting component 2, such as Figure 5 , Figure 6As shown, the device includes a limiting base 2-5 fixed to a tooling plate 5. A limiting fixing plate 2-2 is vertically welded to the limiting base 2-5. Reinforcing ribs 2-1 with a thickness of 5mm are welded to both sides of the limiting fixing plate 2-2 to enhance the strength of the limiting fixing plate 2-2 and protect the limiting component 2. The limiting fixing plate 2-2 has four round holes for sliding connection of four limiting support columns 2-6. The four limiting support columns 2-6 are fixedly connected to the limiting plate 2-3. Pressure sensors 2-4 are embedded in the middle of the fixed plate 2-2, between the four limiting support columns 2-6. The sensing surface of the pressure sensor 2-4 contacts the limiting plate 2-3, which in turn contacts the battery cell, transmitting the battery cell pressure to the pressure sensor 2-4. The pressure sensor 2-4 is electrically connected to the digital display screen 4 via an RS485 interface and transmits signals to the digital display screen 4 through wires. The pressure sensor 2-4 monitors the pressure in real time to ensure that the product preload is within the qualified range, thus protecting the product. When the battery cells are stacked, the limiting plate 2-3 limits and fixes the battery cells. After being subjected to the pressure of the battery cells, the limiting plate 2-3 slides, transmitting the force to the pressure sensor 2-4, achieving accurate pressure detection. The limiting and fixing plate 2-2 provides rigid support, ensuring that the pressure sensor 2-4 only bears axial force (without lateral force interference), improving detection accuracy.

[0053] The preload device 3, such as Figure 7 As shown, it includes: a contact plate 3-1, a pre-tightening fixing plate 3-2, a handle 3-3, a reinforcing plate 3-4, a guide post 3-5, a rotating shaft 3-6, and a pre-tightening base 3-7. The pre-tightening base 3-7 is fixed to the surface of the tooling plate 5. The pre-tightening fixing plate 3-2 is vertically welded to the pre-tightening base 3-7 to form a whole, and the overall firmness is reinforced by the reinforcing plate 3-4. The contact plate 3-1 is slidably connected to the pre-tightening fixing plate 3-2 through the guide post 3-5. The pre-tightening fixing plate 3-2 has four round holes that slidably connect four guide posts 3-5. The guide posts 3-5 are evenly distributed in a circumferential array around the rotating shaft 3-6 to control the movement of the contact plate 3-1 perpendicular to the tooling plate 5 to achieve uniform pressure on the surface of the battery cell module. The guide post 3-5 has a diameter of 20mm. The contact plate 3-1 limits and fixes the product end plate.

[0054] The pre-tightening fixing plate 3-2 has a threaded hole extending through it along its thickness direction. The rotating shaft 3-6 partially passes through this threaded hole and has an external thread on its outer circumference that mates with it. One end of the rotating shaft 3-6 is fixedly connected to the handle 3-3, and the other end abuts against the contact plate 3-1. The guide post 3-5 slides through the pre-tightening fixing plate 3-2 and is fixed at one end to the contact plate 3-1. Clockwise rotation of the handle 3-3 pushes the contact plate 3-1 towards the battery cell module, applying an adjustable pre-tightening force of 0-5000N. The pre-tightening force device 3 applies pre-tightening force to the product to achieve the designed product dimensions through clockwise rotation of the handle 3-3. The handle 3-3 pushes the contact plate 3-1 via mechanical transmission, and the guide post 3-5 ensures that the contact plate 3-1 moves in a straight line (avoiding skew), enabling manual adjustment of the pre-tightening force. The structure is simple and reliable, easy to operate, and suitable for flexible production in small to medium batches.

[0055] The cell stacking pre-tightening process of the cell stacking pre-tightening device described in Embodiment 1 is as follows: Figure 2-8 As shown:

[0056] 1. Positioning of the tab bracket: Place the tab bracket into the bracket positioning frame 1, and insert the tab bracket fixing pins 1-14 of the upper limit plate 1-1 and the lower limit plate 1-2 into the tab bracket positioning hole to complete the three-dimensional positioning; push the bracket positioning frame 1 along the slide rail 1-4 to the stacking station, and insert the fixing pin 1-5 through the positioning hole on the bracket positioning block 1-13 and into the positioning hole on the bracket positioning frame 1 to fix the bracket positioning frame 1.

[0057] 2. Cell stacking: The soft-pack cells are placed layer by layer into the cubic stacking space a. The cell support block 6 ensures that the cells are horizontal, and the limiting plates 2-3 limit the cell offset.

[0058] 3. Preload adjustment: Rotate the handle 3-3 of the preload device 3, the contact plate 3-1 compresses the battery cell module, and the digital display screen 4 displays the pressure value detected by the pressure sensor 2-4 in real time (accuracy ±10N). Stop after adjusting to the design value (e.g. 2000N).

[0059] 4. Module removal: Pull up the drive arm 1-9 to disengage the buckle 1-6 from the retaining ring 1-8, remove the upper limit plate 1-1, pull out the bracket positioning frame 1 along the slide rail 1-4, and the pre-tightened battery cell module can be removed.

[0060] Example 2

[0061] Example 2 provides a cell stacking pre-tightening device, which differs from Example 1 in that: the tooling plate is replaced by the table surface of a workbench, which is the base plate. A slide rail is fixed along the second direction of the table surface, which is the direction in which the electrode bracket moves. The bracket positioning frame is slidably mounted on the table surface via the slide rail. The slide rail is a linear slide rail with a length of 300mm and is fixed to the table surface by M8 bolts. The limiting component and the pre-tightening device are arranged opposite to each other on the first direction of the table surface, which is the direction of cell stacking. The second direction is perpendicular to the first direction in the plane of the base plate. The limiting component, the pre-tightening device, and a pair of oppositely arranged bracket positioning frames together constitute a cubic stacking space for stacking cells.

[0062] The preload device employs a worm gear meshing mechanism: the worm is connected to the handle via a flat key, and both ends of the worm are mounted on the preload fixing plate via bearing assemblies; one end uses an angular contact ball bearing to bear radial and axial forces, while the other end slides with the preload fixing plate via a guide spline sleeve, restricting the worm to axial movement only and preventing rotation around its own axis; the worm gear is mounted in the worm gear box via a deep groove ball bearing, and the worm gear box is fixed to the side of the preload fixing plate, meshing with the worm (the axial module of the worm and the end face module of the worm gear are the same). (Number matching); the end of the worm gear is connected to the contact plate through a rigid thrust bearing to transmit axial thrust. Two T-shaped sliding grooves are added to the bottom of the contact plate, which slide and cooperate with the contact plate slide rail on the table to ensure the linear motion accuracy of the contact plate. The axial module of the worm gear is 2.5, the end module of the worm wheel is 2.5, and the gear ratio is 1:20, ensuring that the contact plate moves 0.5mm when the handle is rotated 1 revolution. A guide post is fixed on the contact plate, and the guide post slides and cooperates with the guide hole on the pre-tightening plate to further constrain the deflection of the contact plate. Rotating the handle drives the worm gear to rotate, and drives the worm wheel to rotate freely through the meshing of the helical teeth (the worm wheel does not output torque, but only serves as a reaction force support for the axial propulsion of the worm gear). At the same time, the worm gear advances linearly along the axial direction, pushing the contact plate to apply pre-tightening force to the movement of the cell module.

[0063] The guide posts are made of carbon fiber and are fitted with linear bearing guide sleeves for sliding contact. The surfaces of the guide posts are polished to reduce the coefficient of friction. The linear bearing guide sleeves are embedded in the holes of the pre-tightening plate, and the guide posts and guide sleeves make rolling contact with each other through ball bearings to avoid jamming. In addition, the number of guide posts has been reduced from four to three, arranged in an equilateral triangle array around the worm gear, which reduces the overall weight of the device while ensuring stability.

[0064] The limiting support columns are made of carbon fiber and are slidably fitted with linear bearing guide sleeves. There are three limiting support columns, and their surfaces are polished to reduce the coefficient of friction. The linear bearing guide sleeves are embedded in the holes of the limiting fixing plate. The limiting support columns and guide sleeves are in rolling contact with ball bearings to avoid jamming. The limiting support columns are evenly distributed in an array around the pressure sensor to ensure that the limiting plate moves perpendicular to the platform and to ensure the uniformity of pressure on the surface of the battery cell module.

[0065] The snap-fit ​​mechanism uses a spring to apply the snap-fit ​​force. The snap-fit ​​includes a snap ring and a spring. One end of the spring is fixed to the support plate, and the other end is fixedly connected to the snap ring. Pulling the snap ring forcefully stretches the spring and causes the snap ring to snap into and lock into the snap-fit ​​interface. A positioning pin is added to the upper outer end face of the support plate. When the upper positioning plate is close, the positioning pin can be embedded into the positioning hole of the upper positioning plate to form a snap-fit ​​positioning guarantee. Together with the spring snap-fit ​​force, it realizes the snap-fit ​​and locking function between the upper positioning plate and the support plate.

[0066] The main body of the battery cell support block is a cuboid, with its bottom positioned in a positioning hole on the platform via a protruding positioning pin. The top of the support block has a wear-resistant and anti-slip layer to prevent the battery cells from sliding laterally during stacking. Compared to the support block in Embodiment 1, this design is easier to position and is both anti-slip and wear-resistant.

[0067] While maintaining the core functions of Example 1, the above alternative solutions provide another flexible production scenario for battery cell modules through the worm gear and worm wheel meshing adjustment design.

[0068] Example 3

[0069] Example 3 provides a cell stacking pre-tightening device, which differs from Example 1 in that: the clamping mechanism in Example 3 uses a magnetic quick-release structure to replace the mechanical engagement of the buckle and the interface: neodymium iron boron strong magnets and low carbon steel gaskets are embedded in the mating surfaces of the upper limit plate and the support plate, respectively. The magnetic strength of the neodymium iron boron strong magnets is ≥1500N, and quick positioning and locking are achieved through magnetic attraction; a spring top pin is added to the upper outer end face of the support plate. When the upper limit plate approaches, the top pin automatically engages with the positioning hole of the upper limit plate, forming a double anti-loosening guarantee. Compared with the buckle structure of Example 1, the magnetic design has no mechanical wear, shortens the assembly and disassembly time to within 1 second, and avoids the fatigue fracture problem caused by frequent buckle operation.

[0070] The above description is only a preferred embodiment of the utility model, but the protection scope of the utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed by the utility model, based on the technical solution and the utility model concept, should be included within the protection scope of the utility model.

[0071] The description briefly mentions the application direction of the utility model in relation to existing technologies known to those skilled in the art without modification, and combines them with the utility model to form a complete technology; it avoids excessive popularization of technologies known to those skilled in the art, in order to help those skilled in the art quickly understand the main content of the utility model.

Claims

1. A cell stacking pre-tightening device, characterized in that, It includes limit components, pre-tightening devices, bracket positioning frames, base plates, and pressure sensing and display devices; The limiting component and the pre-tightening device are sequentially disposed on the base plate along the first direction and are distributed opposite to each other. The limiting component, the pre-tightening device, and a pair of bracket positioning frames arranged opposite each other along the second direction together constitute a cubic stacking space for stacking battery cells to form a battery cell module; the first direction is perpendicular to the second direction; The pre-tightening device is movably mounted on the base plate and is used to push the battery cell module to move along the first direction and abut against the limiting component, so as to apply a pre-tightening force to the stacked battery cell modules. The bracket positioning frame is slidably mounted on the base plate along a direction parallel to the second direction, and is used to drive the tab bracket to move along a direction parallel to the second direction to position and install it on the end of the cell module where the tab is located. The pressure sensing and display device is used to receive the preload force on the battery cell module to sense and display the preload force of the battery cell module in real time.

2. The cell stacking pre-tightening device according to claim 1, characterized in that, The pressure sensing and display device includes a pressure sensor and a digital display screen. The digital display screen is embedded in the surface of the base plate and electrically connected to the pressure sensor embedded in the limiting component. The pressure sensor is used to withstand the pressure of the battery cell and transmit the pressure value to the digital display screen.

3. The cell stacking pre-tightening device according to claim 2, characterized in that, The limiting assembly includes a limiting fixing plate and a limiting plate. The limiting fixing plate is vertically fixed to the surface of the base plate. The limiting plate and the limiting fixing plate are slidably connected. The pressure sensor is embedded between the limiting fixing plate and the limiting plate.

4. The cell stacking pre-tightening device according to claim 3, characterized in that, The limiting plate and the limiting fixing plate are slidably connected by limiting support columns. At least three limiting support columns are configured to slide and engage with holes on the limiting fixing plate. The limiting support columns are evenly distributed in an array around the pressure sensor and are used to ensure that the limiting plate moves perpendicular to the base plate to ensure the uniformity of pressure on the surface of the battery cell module.

5. The cell stacking pre-tightening device according to claim 1, characterized in that, The preload device includes a preload fixing plate fixed above the base plate, a contact plate slidably mounted on the preload fixing plate in a direction parallel to the first direction, and a drive unit connected to the contact plate and used to drive it to reciprocate in a direction parallel to the first direction to apply a preload to the cell module.

6. The cell stacking pre-tightening device according to claim 5, characterized in that, The drive unit includes a handle, a rotating shaft, and a guide post. The pre-tightening fixing plate has a threaded hole extending through it along its thickness direction. The rotating shaft partially passes through the threaded hole and has an external thread on its outer circumference that mates with the threaded hole. One end of the rotating shaft is fixedly connected to the handle, and the other end abuts against the contact plate. The guide post slides through the pre-tightening fixing plate and is fixed at one end to the contact plate. By rotating the handle, the contact plate moves toward the battery cell module to apply a pre-tightening force to it.

7. The cell stacking pre-tightening device according to claim 6, characterized in that, The end of the rotating shaft near the contact plate abuts against the contact plate via a bearing, and / or The guide posts are configured as at least three and are evenly distributed in a circumferential array around the rotation axis to control the contact plate to move perpendicular to the base plate so as to achieve uniform pressure on the surface of the battery cell module.

8. The cell stacking pre-tightening device according to claim 1, characterized in that, The bracket positioning frame includes: The support plate is slidably mounted on the base plate along a direction parallel to the second direction. It is configured as a U-shaped frame structure with a notch at the top and an inner wall with a mounting groove for accommodating the tab bracket. The upper positioning plate is detachably connected to the support plate via a snap-fit ​​mechanism and is used to cover the notch to position the tab bracket located inside the mounting slot.

9. The cell stacking pre-tightening device according to claim 8, characterized in that, The mounting groove is formed at the bottom and inner walls of both sides of the support plate, and extends from the inner bottom surface of the support plate to the top notch. The bottom mounting groove of the support plate and the side of the upper positioning plate opposite to the mounting groove are both provided with positioning holes. The positioning of the electrode bracket along the height direction is achieved by a fixing pin passing through the positioning hole.

10. The cell stacking pre-tightening device according to claim 8, characterized in that, The latching mechanism includes a latch and a latching interface that cooperate with each other. The latch is disposed on the support plate, and the latching interface is disposed on the upper limit plate. The latch and the latching interface are engaged and locked together to achieve a detachable connection between the upper limit plate and the support plate.

11. The cell stacking pre-tightening device according to claim 8, characterized in that, The bottom of the support plate is provided with a sliding groove that is slidably connected to a slide rail fixed on the base plate. The bottom end face of the support plate is provided with positioning holes on both sides. The base plate surface on both sides of the bottom of the support plate is fixed with a bracket positioning block parallel to the slide rail. The bracket positioning block has a positioning hole, and a fixing pin is inserted into the positioning hole. The fixing pin passes through the positioning hole to fix the bracket positioning frame at the cell stacking position.

12. The cell stacking pre-tightening device according to claim 8, characterized in that, A cell support block is provided between the pre-tightening device and the limiting component. The pre-tightening device, the limiting component, the cell support block, and the bracket positioning frame enclose a cubic stacking space. The thickness of the cell support block is equal to the vertical distance from the upper surface of the bottom mounting groove of the support plate to the upper surface of the base plate, which is used to support the cells and maintain the stacked horizontal position.

13. The cell stacking pre-tightening device according to claim 8, characterized in that, The upper limit plate has a rectangular notch at one end of the cell stack to ensure that the cells have sufficient displacement space when stacking.

Images