A power battery cell shell processing device and method

Abstract

The application discloses a kind of power battery's shell processing device and method of electric core, including conveying mechanism, and the conveying line of conveying mechanism is sequentially provided with pre-shaping station, rotary cutting station, polishing station and angle supporting station.The pre-shaping station is equipped with positioning mechanism and symmetrically arranged pre-shaping mechanism.Positioning mechanism is fixed on conveying mechanism by stopping shell with baffle and by lifting part pressing plate;Pre-shaping mechanism adopts double-layer driving structure, including outer mold cylinder, outer mold cylinder mounting plate, inner mold cylinder and die assembly.When working, outer mold cylinder drives mounting plate to translate, so that outer mold covers the outside of shell opening of electric core shell first, then inner mold cylinder on mounting plate drives inner mold to extend into shell opening cavity, and pre-shaping of shell opening R angle and tube type is realized by extrusion cooperation of inner and outer mold.The application carries out forced shaping to shell opening before rotary cutting, and improves the adaptability and welding yield of power battery packaging.

Description

Technical Field

[0001] This invention discloses a battery cell casing processing apparatus and method, belonging to the field of battery cell casing processing technology. Background Technology

[0002] With the global energy structure transformation, the traditional gasoline vehicle market is shrinking, leading to a reduction in powertrain production lines. Conversely, the sales of new energy vehicles have experienced explosive growth in recent years, creating a staggering demand for power batteries. In the new energy vehicle sector, power batteries are typically manufactured using 3003 rectangular aluminum alloy thin-walled shells (wall thickness typically ≤0.4mm) with high thermal conductivity and good formability. As the industry's requirements for power battery range, safety, and energy density continue to increase, the need to maximize the effective use of internal space within the battery is growing. This places higher demands on the manufacturing precision of the rectangular aluminum alloy thin-walled shells and their packaging processes.

[0003] In the assembly process of power batteries, the dimensional accuracy of the aluminum alloy cell casing opening is crucial. The casing opening must strictly conform to the design drawings and maintain good compatibility with the electrode cover plate to ensure the stability of the automated assembly line, improve production efficiency, guarantee the quality of subsequent laser welding, and reduce the occurrence of defects such as incomplete welding and leakage.

[0004] Currently, the aluminum alloy cell casings for power batteries mostly employ low-cost, high-efficiency production processes. These involve rapidly rolling ultra-thin aluminum alloy strips together using high-speed continuous rolling, followed by online high-frequency induction welding, and then processing them on a rotary cutting line. A typical rotary cutting process includes: rotary cutting, deburring, and corner shaping of the casing opening. In the rotary cutting process, a set of outer molds typically holds the outer perimeter of the casing opening. A die cutter inserts into the casing opening, fitting snugly against the outer mold, and rotates to cut flat from the inside out, ensuring burrs are turned outwards. Subsequently, an inner mold is inserted into the casing opening to perform corner shaping, standardizing the shape and dimensions of the four inner radius corners of the casing opening.

[0005] However, in actual production processes, the aforementioned existing technologies have the following significant drawbacks: 1. Roll forming causes R-angle deviation: The shape, dimensions, and flatness of the rectangular tube shell depend entirely on the precision of each axis and mold in the roll forming production line. As it is a thin-walled part (≤0.4mm), during the roll forming process, the four R-angles (inner and outer R-angles) of the shell opening often deviate from the theoretical design values ​​due to various random factors.

[0006] 2. Rotary cutting and flanging affect welding quality: During the rotary cutting process, if the outer radius (R-angle) of the shell opening is not tightly fitted with the inner radius (R-angle) of the rotary cutting mold (a gap exists), when the die cutter cuts from the inside out, large burrs and outward flanging are easily generated at the R-angle. This flanging is difficult to clean in the subsequent grinding process and will directly and seriously affect the laser welding quality during packaging.

[0007] 3. Difficulty in correcting the corner support process: In the subsequent corner support process, if the initial radius (R) shape deviation is too large, it cannot be standardized through simple corner support movements. If the corner support correction is too large, it will cause the wall thickness at the R to become thinner, resulting in an excessive gap during cap welding and causing poor soldering; if the corner support is insufficient, it will cause poor cap welding and affect the packaging efficiency.

[0008] 4. Limited measurement accuracy: Thin-walled aluminum alloy parts are prone to deformation, and the instability of the corner support process directly affects the numerical changes of the shell opening measurement points (inner length, inner width, etc.), resulting in a decrease in the pass rate of the submitted dimensions.

[0009] Therefore, how to provide a device that can pre-shape the blank tube opening precisely so that the tube shape and R-angle of the opening meet or approach the theoretical design requirements before entering the rotary cutting process has become a key issue in improving the yield and packaging quality of power battery aluminum shells. Summary of the Invention

[0010] To address the issues that arise in existing power battery rectangular aluminum alloy thin-walled shells after continuous roll forming, where random deviations in the shell opening radius (R-angle) lead to problems such as flanging and burrs in subsequent rotary cutting processes due to poor fit between the shell and the mold, and excessive correction in subsequent corner-supporting processes resulting in thinner walls and difficulty in closing the shell, this invention provides a power battery cell shell processing device and method. The aim is to improve the dimensional accuracy and shape stability of the shell opening through a pre-shaping process before rotary cutting.

[0011] The present invention provides a battery cell casing processing device, including a conveying mechanism, wherein the conveying mechanism is provided with a positioning structure for positioning the aluminum alloy battery cell casing, and a plurality of processing stations are arranged sequentially on the conveying line of the conveying mechanism, wherein the first processing station is a pre-shaping station.

[0012] The pre-shaping station is equipped with a positioning mechanism and a pre-shaping mechanism. The pre-shaping device includes pre-shaping units symmetrically arranged on both sides of the conveying mechanism, which are used to simultaneously pre-shape the two end openings of the battery cell casing. The specific structure is as follows: The positioning mechanism includes a lifting mechanism arranged perpendicular to the conveying mechanism and a part pressure plate connected to the lifting mechanism. The part pressure plate is arranged parallel to the aluminum alloy cell shell of the power battery and is used to drive the part pressure plate down through the lifting mechanism to fix the cell shell.

[0013] The pre-shaping mechanism includes an outer mold cylinder, an outer mold cylinder mounting plate driven by the outer mold cylinder to perform linear motion, and an inner mold cylinder and mold assembly mounted on the outer mold cylinder mounting plate.

[0014] The mold assembly includes an outer mold and an inner mold. The outer mold is fixed to the outer mold cylinder mounting plate and has a mold hole that matches the design shape of the battery cell shell. The inner mold is connected to the output end of the inner mold cylinder and has a shaping part for extending into the opening of the battery cell shell.

[0015] Working principle: The outer mold cylinder drives the outer mold cylinder mounting plate to move, which in turn drives the outer mold, inner mold cylinder and inner mold to move axially closer to the battery cell shell, so that the outer mold covers the outside of the shell opening. Then the inner mold cylinder drives the inner mold to extend into the inner cavity of the shell opening. The extrusion and cooperation of the outer mold and inner mold realizes the pre-shaping of the R angle and tubular shape of the battery cell shell opening.

[0016] Furthermore, the aluminum alloy cell shell of the power battery of the present invention is a rectangular aluminum alloy thin-walled shell blank tube with a wall thickness of ≤0.4mm, and its four corners are provided with inner and outer R-angles formed by roll bending.

[0017] Furthermore, the outer mold of the present invention is a block structure with a rectangular through hole and rounded corners corresponding to the designed outer R angle. An outwardly expanding guide bevel is provided on the side facing the battery cell shell; a baffle is provided on the side away from the battery cell shell for axial limiting, and the baffle is provided with a clearance hole for the inner mold to pass through.

[0018] Furthermore, the front shaping part of the inner mold of the present invention is a solid rectangular columnar structure with rounded corners corresponding to the designed inner R corners, and a narrowed guide slope is provided at the front end.

[0019] Furthermore, the positioning structure on the conveying mechanism of the present invention includes multiple sets of positioning components, each set consisting of four mirror-symmetrical positioning blocks. The spacing between the positioning slots on the positioning blocks corresponds to the width of the battery cell casing, ensuring conveying accuracy.

[0020] Furthermore, the multiple processing stations of the present invention sequentially include a pre-shaping station, a rotary cutting station, a grinding station, and a corner support station.

[0021] The present invention also provides a processing method, comprising: S1. positioning and clamping; S2. the outer mold cylinder drives the mounting plate to move horizontally, the outer mold is fitted into the shell opening, and the inner mold moves to the position accordingly; S3. the inner mold cylinder drives the inner mold to extend into the shell opening, and the inner and outer molds cooperate to extrude and shape; S4. the inner mold retracts first, the outer mold assembly retracts, and the baffle plate and pressure plate are released; S5. the material is transferred to the subsequent rotary cutting, grinding, and corner support stations.

[0022] This invention has the following significant advantages: 1. Significantly improved welding quality: By pre-shaping before rotary cutting, the R-angle of the shell opening is perfectly fitted with the outer die of rotary cutting, completely eliminating the flanging and burrs during the rotary cutting process, ensuring the reliability of subsequent laser welding. 2. Reduced production scrap rate: Pre-shaping reduces the amount of correction required in the subsequent corner support process, avoiding the problem of thinning of the wall thickness at the R-angle due to excessive corner support or insufficient corner support leading to poor capping, greatly improving the finished product qualification rate. 3. Ingenious and stable structural design: Adopting a "dual-layer drive" structure (the outer die cylinder drives the inner die assembly to move as a whole), it achieves a precise timing sequence of first covering the outer die and then inserting the inner die, resulting in a compact structure and high positioning accuracy. 4. Strong adaptability: The die is equipped with an inlet bevel and a guiding slope, which can effectively cope with the shape deviation caused by rolling of ultra-thin blank tubes, ensuring the smooth operation of the automated production line. 5. Improved compatibility: It ensures a 100% compatibility success rate between the cell shell and the electrode covers at both ends, greatly improving the production efficiency of the power battery packaging line. Attached Figure Description

[0023] To more clearly illustrate the technical solutions of the embodiments disclosed in this invention, the accompanying drawings of the embodiments will be briefly described below. These drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention.

[0024] Figure 1 This is a schematic diagram of the overall process layout of the battery cell casing processing device provided by the present invention. Figure 2 This is a schematic diagram of the pre-shaping unit in this invention; Figure 3 This is an axial sectional view of the pre-shaping unit in this invention; Figure 4 This is a schematic diagram of the structure of the outer mold in this invention; Figure 5 This is a schematic diagram of the inner mold structure in this invention; Figure 6 This is a schematic diagram of the battery cell casing in this invention. Detailed Implementation

[0025] The technical solutions (including preferred technical solutions) of the present invention will be further described in detail below with reference to the accompanying drawings and by way of listing some optional embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] like Figure 1-6 As shown, this embodiment provides a battery cell casing processing apparatus, mainly used for processing such as... Figure 2The rectangular aluminum alloy thin-walled shell blank tube shown is referred to as the battery cell shell 2. The battery cell shell 2 is a rectangular tube formed by continuous rolling and high-frequency induction welding of ultra-thin aluminum alloy strip, with a wall thickness of ≤0.4mm.

[0027] The present invention includes a conveying mechanism 1, on which a pre-shaping station 100, a rotary cutting station 200, a grinding station 300 and a corner support station 400 are sequentially arranged. The conveying mechanism 1 is provided with a positioning component 11 for positioning the battery cell housing 2, including multiple sets of positioning blocks arranged at equal intervals along the conveying direction to ensure the radial stability of the housing during conveying.

[0028] The pre-shaping station 100, as the first process in the production line, is the core of this device. It includes a positioning mechanism 3, a pre-shaping mechanism 4, and a material stop and limit mechanism 5, which work together in multiple dimensions to achieve high-precision fixing and deformation correction of the shell opening.

[0029] The positioning mechanism 3 is used to vertically press and fix the battery cell housing 2. It includes a lifting mechanism 31 arranged perpendicular to the conveying mechanism 1 and a part pressure plate 32 connected to the bottom of the lifting mechanism 31. The part pressure plate 32 is arranged parallel to the top surface of the battery cell housing 2. The lifting mechanism 31 drives the part pressure plate 32 to press down, which, together with the positioning component 11 on the conveying mechanism 1, firmly locks the battery cell housing 2 in the processing position, preventing jumping or displacement during shaping.

[0030] The pre-shaping mechanism 4 is symmetrically arranged on both sides of the conveying mechanism 1, and it adopts a unique two-stage drive logic. The pre-shaping mechanism 4 includes an outer mold cylinder 41, an outer mold cylinder mounting plate 42 driven by the outer mold cylinder to perform linear motion, an inner mold cylinder 43 mounted on the outer mold cylinder mounting plate 42, and a mold assembly.

[0031] The mold assembly includes an outer mold 44 and an inner mold 45. The outer mold 44 is fixed on the outer mold cylinder mounting plate 42 and has a rectangular through hole 441. Its side facing the shell has an outwardly expanding guide bevel 442. The inner mold 45 is connected to the output end of the inner mold cylinder 43. Its front end has a solid rectangular shaping section 451 with a rounded corner structure corresponding to the designed inner R-angle, and its frontmost end has a narrowed multi-faceted guide slope 452. The outer mold cylinder 41 drives the mounting plate 42 to move, simultaneously moving the outer mold 44, inner mold cylinder 43, and inner mold 45 axially closer to the shell, completing the first layer of covering action. Subsequently, the inner mold cylinder 43 drives the inner mold 45 to extend into the shell opening, completing the second layer of shaping action.

[0032] As a further optimization of this embodiment, a material blocking and limiting mechanism 5 is provided on the side of the conveying mechanism 1 of the pre-shaping station 100. This mechanism includes a material blocking cylinder 51 and a material blocking plate 52 connected to its output end.

[0033] In operation, the axial direction of the baffle cylinder 51 is perpendicular to the axis of the conveying mechanism 1. Before the battery cell housing 2 is conveyed to the pre-shaping position, the baffle cylinder 51 drives the baffle plate 52 to rise or extend into the conveying path. The baffle surface of the baffle plate 52 is perpendicular to the conveying direction. When the battery cell housing 2 moves to the preset position with the conveying mechanism 1, its front end surface contacts the baffle plate 52 and stops, thereby achieving precise physical limiting in the conveying direction (axial direction). This, combined with the vertical pressing of the part pressure plate 32, constructs a "three-dimensional locking" positioning system, ensuring extremely high repeatability.

[0034] The operational logic of this device in actual production is as follows: S1. Interception and Clamping: First, the baffle cylinder 51 is activated, extending the baffle plate 52 above the conveyor track. The conveyor mechanism 1 sends the battery cell housing 2 into the pre-shaping station, where the front end of the housing impacts the baffle plate 52 to stop axially. Subsequently, the lifting mechanism 31 drives the part pressure plate 32 to move vertically downward, completely clamping and fixing the housing.

[0035] S2. Outer Mold Positioning: The outer mold cylinder 41 is activated, driving the outer mold cylinder mounting plate 42 to move horizontally towards the battery cell casing. The outer mold 44, fixed on the plate, first fits into the outer side of the battery cell casing opening. Due to the limiters at both ends, the outer mold can play a further micro-correction role when fitting in. At the same time, the inner mold cylinder 43 moves synchronously with the mounting plate to the ready-to-work position.

[0036] S3. Inner mold shaping: The inner mold cylinder 43 is activated, driving the inner mold 45 to pass through the clearance hole at the rear end of the outer mold and extend into the inner cavity of the battery cell outer shell opening. The inner mold fillet matches the outer mold fillet, forcibly extruding and shaping the inner and outer R-angles of the shell opening wall to eliminate roller pressure deviation.

[0037] S4. Mold Retraction and Release: After shaping, the inner mold 45 first exits the housing, and then the outer mold cylinder 41 drives the entire assembly to retract to its original position. The part pressure plate 32 lifts to release the housing. At the same time, the baffle cylinder 51 retracts, driving the baffle plate 52 to descend and clear the conveying path.

[0038] S5. Process flow: After the pre-shaping is completed, the battery cell shell 2 flows with the conveying mechanism 1 and enters the rotary cutting station 200, the grinding station 300 and the corner support station 400 in sequence.

[0039] As can be seen from the above specific embodiments, the present invention solves the problem of flanging of ultra-thin aluminum alloy shells during rotary cutting by using three-dimensional locking positioning and a double-layer drive shaping mechanism in the pre-shaping station, and greatly reduces the damage to the wall thickness caused by subsequent corner support processes, thus significantly improving the packaging quality and production efficiency of power battery cell shells.

[0040] It will be readily understood by those skilled in the art that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, combinations, substitutions, improvements, etc., made under the spirit and principles of the present invention are included within the protection scope of the present invention.

Claims

1. A processing apparatus for the cell casing of a power battery, characterized in that, The device includes a conveying mechanism, which is equipped with a positioning structure for positioning the aluminum alloy cell shell of a power battery. The conveying mechanism has multiple processing stations arranged sequentially along its conveying line, the first of which is a pre-shaping station. The pre-shaping station is equipped with a positioning mechanism and a pre-shaping mechanism. The pre-shaping device includes pre-shaping units symmetrically arranged on both sides of the conveying mechanism, which are used to simultaneously pre-shape the two end openings of the cell shell. The positioning mechanism includes a baffle mechanism arranged perpendicular to the direction of the conveying mechanism and a baffle plate connected to the baffle mechanism. The baffle plate is arranged perpendicular to the aluminum alloy cell shell of the power battery and blocks both ends of the shell for positioning the shell. The positioning mechanism also includes a lifting mechanism and a part pressure plate connected to the lifting mechanism. The part pressure plate is arranged parallel to the aluminum alloy cell shell of the power battery and is used to drive the part pressure plate down through the lifting mechanism to fix the cell shell. The pre-shaping mechanism includes an outer mold cylinder, an outer mold cylinder mounting plate driven by the outer mold cylinder to perform linear motion, and an inner mold cylinder and mold assembly mounted on the outer mold cylinder mounting plate; The mold assembly includes an outer mold and an inner mold. The outer mold is fixed to the outer mold cylinder mounting plate and has a mold hole that matches the design shape of the battery cell shell. The inner mold is connected to the output end of the inner mold cylinder and has a shaping part for extending into the opening of the battery cell shell. The outer mold cylinder drives the outer mold cylinder mounting plate to move, simultaneously driving the outer mold, inner mold cylinder and inner mold to move axially closer to the battery cell shell, so that the outer mold covers the outside of the shell opening. Then the inner mold cylinder drives the inner mold to extend into the inner cavity of the shell opening. The extrusion and cooperation of the outer mold and the inner mold realizes the pre-shaping of the R-angle and tubular shape of the battery cell shell opening.

2. The battery cell casing processing apparatus according to claim 1, characterized in that: The outer shell of the power battery aluminum alloy cell is a rectangular aluminum alloy thin-walled shell blank tube with a wall thickness of ≤0.4mm. The cross-section of the blank tube is rectangular, and each of its four corners is provided with an inner R-angle and an outer R-angle formed by roll bending. Both ends of the blank tube have a through shell opening to be shaped.

3. The battery cell casing processing apparatus according to claim 1, characterized in that: The outer mold is a block structure with a rectangular through hole. The inner contour shape of the rectangular through hole is adapted to the theoretical design outer contour shape of the battery cell shell, and the four inner corners of the rectangular through hole are provided with rounded corner structures corresponding to the outer R corners of the battery cell shell design.

4. The battery cell casing processing apparatus according to claim 3, characterized in that: The rectangular through hole has an outwardly expanding inlet bevel on the side facing the cell casing.

5. The battery cell casing processing apparatus according to claim 3, characterized in that: The outer mold is provided with a baffle for axially limiting the battery cell housing on the side away from the battery cell housing. The baffle is provided with a clearance hole for the inner mold to pass through. The shape of the clearance hole is smaller than that of the rectangular through hole.

6. The battery cell casing processing apparatus according to claim 1, characterized in that: The inner mold includes a fixed connection part and a shaping part located at the front end. The shaping part is a solid rectangular columnar structure, and its cross-sectional outline is adapted to the theoretical design inner cavity shape of the battery cell shell. The four outer corners of the shaping part are provided with rounded corner structures corresponding to the inner R corners of the battery cell shell design.

7. The battery cell casing processing apparatus according to claim 6, characterized in that: The front end of the shaping section is provided with a guide slope that narrows toward the central axis.

8. The battery cell casing processing apparatus according to claim 1, characterized in that: The positioning structure on the conveying mechanism includes multiple sets of positioning components arranged at equal intervals along the conveying direction of the conveying mechanism. Each set of positioning components includes four positioning blocks arranged in a mirror symmetrical manner. Each positioning block is provided with a positioning groove. The spacing between the positioning grooves on two positioning blocks located on the same side corresponds to the width of the battery cell casing.

9. The battery cell casing processing apparatus according to claim 1, characterized in that: The multiple processing stations set up in sequence include a pre-shaping station, a rotary cutting station, a grinding station, and a corner support station.

10. A method for processing using the apparatus according to any one of claims 1-9, characterized in that, Includes the following steps: S1, the conveying mechanism sends the battery cell casing to the pre-forming station, the baffle mechanism drives the baffle plate to move vertically downward to block the two ends of the casing for positioning, and the lifting mechanism drives the part pressure plate to move vertically downward to press the battery cell casing onto the positioning structure of the conveying mechanism. S2, the outer mold cylinder starts, driving the outer mold cylinder mounting plate to move horizontally towards the battery cell shell, so that the outer mold is first fitted into the outer side of the battery cell shell opening, while the inner mold cylinder moves synchronously with the mounting plate to the ready-to-work position. S3, the inner mold cylinder is started, driving the inner mold to extend into the inner cavity of the battery cell outer shell opening. The rounded corner structure of the outer corner of the inner mold matches the rounded corner structure of the inner hole of the outer mold, forcibly extruding and shaping the inner and outer R corners of the shell opening wall to eliminate roller pressure deviation. S4. After the shaping is completed, the inner mold cylinder first drives the inner mold to exit, and then the outer mold cylinder drives the outer mold and inner mold assembly to return to their original positions as a whole. The lifting mechanism drives the part pressure plate to lift up and release the battery cell shell. S5, the battery cell casing is sequentially transferred to the subsequent rotary cutting station, grinding station and corner support station by the conveying mechanism.

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