Preparation device and preparation method of conductive slurry for lithium ion battery

Abstract

The invention relates to the technical field of conductive slurry preparation, in particular to a preparation device and method of conductive slurry for a lithium ion battery. The preparation device comprises a grinding box, two grinding rollers are rotationally connected between the two opposite side walls of an inner cavity of the grinding box, and a feeding groove is formed in the top of the grinding box; a material pressing mechanism which can be opened and can ascend and descend is installed between the inner walls of the two opposite sides of the feeding groove, the bottom of the material pressing mechanism is conical and faces the gap between the two grinding rollers, and a feeding mechanism is installed at the top of the grinding box. The reciprocating sliding driving part can drive the feeding pipe assembly to slide back and forth along the rectangular groove in a reciprocating mode, when the feeding pipe assembly slides forwards along the lower half portion of the rectangular groove, the pressing mechanism can be opened through the pressing block, and slurry to be ground is evenly conveyed to the grinding roller through sliding of the feeding pipe assembly; and uniform grinding of the slurry is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of conductive paste preparation, in particular to a preparation device and a preparation method of conductive paste for lithium ion batteries. Background Art

[0002] In the preparation process of the existing conductive slurry, the mixed slurry needs to be ground to grind the large particles in the slurry into small particles, so as to improve the mixing effect of the slurry and improve the conductive performance. However, in the existing grinding roller grinding device, the raw materials are fed from the same position of the grinding roller during grinding and feeding, and then flow to both sides. This method causes the use of the grinding roller to be uneven and affects the grinding efficiency of the slurry. At the same time, during the grinding process, some slurry with larger particles will always jump between the grinding rollers and cannot be processed in time. To this end, the present invention has developed a preparation device for conductive slurry for lithium-ion batteries to solve the above problems. Summary of the invention

[0003] The object of the present invention is to provide a device and method for preparing a conductive paste for lithium ion batteries, so as to solve the technical problems raised by the above-mentioned background technology.

[0004] In order to achieve the above-mentioned purpose, the first technical solution provided by the present invention is: A preparation device for a conductive paste for a lithium-ion battery, comprising a grinding box, two grinding rollers are rotatably connected between two opposite side walls of an inner cavity of the grinding box, a feed trough is provided on the top of the grinding box, an openable and liftable pressing mechanism is installed between the inner walls on two opposite sides of the feed trough, and the bottom of the pressing mechanism is conical and faces the gap between the two grinding rollers, and a feeding mechanism is installed on the top of the grinding box; The feeding mechanism includes a box body fixed on the top of the grinding box, a reciprocating sliding drive member is installed between the opposite side walls of the box body inner cavity, a retractable feeding pipe assembly is installed on the reciprocating sliding drive member, the opposite side walls of the box body are symmetrically provided with rectangular grooves with semicircular ends, the outer wall of the telescopic end of the feeding pipe assembly is installed with a pressing block that cooperates with the pressing mechanism, the opposite two ends of the pressing block are respectively slidably connected with the two rectangular grooves, and the opposite two ends of the pressing block are symmetrically provided with reciprocating extrusion members, when the feeding pipe assembly slides along the lower half of the rectangular groove, the feeding pipe assembly is in an extended feeding state and the pressing mechanism is pushed to open to both sides by the pressing block, and when the feeding pipe assembly slides along the upper half of the rectangular groove, the feeding pipe assembly is in a non-feeding state and the pressing mechanism is pushed to reciprocate and rise and fall by the reciprocating extrusion member to press the material.

[0005] Preferably, the feed pipe assembly includes an outer feed pipe fixedly connected to the reciprocating sliding drive member, the inner cavity at the bottom of the outer feed pipe is sealingly and slidingly connected to the inner feed pipe, and the bottom of the inner feed pipe is a closed shape, a transverse axis is installed in the inner cavity of the outer feed pipe, a blocking rod inserted into the inner feed pipe is installed at the bottom of the transverse axis, and the shape of the blocking rod is adapted to the shape of the bottom of the inner feed pipe, when the inner feed pipe contracts, the blocking rod is inserted into the bottom of the inner feed pipe and blocks the inner feed pipe, and the pressing block is fixedly connected to the outer wall of the inner feed pipe.

[0006] Preferably, a first spring is sleeved on the outer wall of the inner feed pipe, and the first spring is located between the top of the pressing block and the bottom of the outer feed pipe.

[0007] Preferably, a rotating shaft is rotatably connected to the inner cavity of the pressure block, and sliding rings that are compatible with the rectangular groove are symmetrically rotatably connected to the opposite ends of the rotating shaft. The reciprocating extrusion piece is a cam piece, and rotating gears are symmetrically fixed to the opposite ends of the rotating shaft, and racks that cooperate with the rotating gears are symmetrically fixed to the inner walls on opposite sides of the box body.

[0008] The two wheels are connected with each other, and the two wheels are connected with each other with a plurality of wheels respectively.

[0009] Preferably, the inner walls on both sides of the box body are symmetrically fixed with limit strips inserted between the bottom of the extrusion strip and the top of the sliding seat, and when the two pressing blocks are in contact with each other, the extrusion strip is separated from the contact of the limit strip, and when the two pressing blocks are separated from each other, the bottom of the extrusion strip is in contact with the top of the limit strip.

[0010] Preferably, a strip groove cooperating with the installation shaft is formed through the side wall of the pressing block along the lifting direction of the pressing block.

[0011] Preferably, the reciprocating sliding drive member includes two reciprocating screw rods, the outer walls of the two reciprocating screw rods are threadedly connected with a slider, the outer wall of the fixed end of the feed pipe assembly passes through the slider, the outer walls of one end of the two reciprocating screw rods pass through the side wall of the box body and are connected through a first belt transmission member, and a driving motor is installed on the grinding box, and the driving motor is connected to a reciprocating screw rod and a grinding roller through a second belt transmission member.

[0012] Preferably, the cross-section of the bottom of the grinding box is semicircular, and a spiral feed shaft is rotatably connected between the inner walls on both sides of the bottom of the inner cavity of the grinding box, the drive shaft of the spiral feed shaft passes through the side wall of the grinding box and is installed with a second driving gear, and the side wall of the grinding box is rotatably connected to a transition gear meshing with the second driving gear, the outer walls of the two reciprocating screws are fixed with incomplete gears, and the transition gear is located between the two incomplete gears and meshed with the two incomplete gears in turn, and a discharge pipe is connected in the middle of the bottom of the grinding box.

[0013] Compared with the prior art, the beneficial effects of the present invention are: When the conductive slurry is ground, the present invention can drive the feed pipe assembly to slide back and forth along the rectangular groove through the reciprocating sliding drive member, and when the feed pipe assembly slides forward along the lower half of the rectangular groove, the pressing mechanism can be opened by the pressing block, and the slurry to be ground is evenly transported to the grinding roller through the sliding of the feed pipe assembly, thereby ensuring that the slurry is evenly ground. When the feed pipe assembly slides back along the upper half of the rectangular groove, it can drive the feed pipe assembly to contract and close the pressing mechanism to form a structure with a conical bottom shape, and then the pressing mechanism is driven to slide back and forth up and down by the reciprocating extrusion member, thereby squeezing the slurry on the grinding roller, so that the slurry with larger particles on the grinding roller can be broken under the action of the extrusion force, thereby improving the grinding effect of the slurry. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0015] Figure 1 It is a schematic structural diagram of the preparation device of the present invention.

[0016] Figure 2 It is a schematic diagram of the front cross-section structure of the preparation device of the present invention.

[0017] Figure 3 for Figure 2 A schematic diagram of the enlarged structure at point A in the middle.

[0018] Figure 4 It is a front view structural schematic diagram of the preparation device of the present invention.

[0019] Figure 5 It is a schematic structural diagram of a feed pipe assembly and its connecting parts in the preparation device of the present invention.

[0020] Figure 6 It is a schematic diagram of the front cross-section structure of the feed pipe assembly and its connecting parts in the preparation device of the present invention.

[0021] Figure 7 It is a schematic diagram of the exploded structure of the material pressing mechanism in the preparation device of the present invention.

[0022] Figure 8 It is a schematic diagram of the internal structure of the box in the preparation device of the present invention.

[0023] In the accompanying drawings, the components represented by the reference numerals are listed as follows: 1. Grinding box; 2. Grinding roller; 21. First driving gear; 3. Feeding trough; 4. Pressing mechanism; 41. Sliding seat; 42. Mounting shaft; 43. Second spring; 44. Pressing block; 45. Sliding column; 46. Extrusion bar; 47. Third spring; 48. Limiting bar; 49. Strip groove; 5. Feeding mechanism; 51. Box; 52. Reciprocating sliding driving member; 521. Reciprocating screw rod; 522. Sliding block; 523. First belt transmission member; 524. Driving driving motor; 525, second belt transmission member; 53, feed pipe assembly; 531, outer feed pipe; 532, inner feed pipe; 533, horizontal axis; 534, blocking rod; 535, first spring; 54, rectangular groove; 55, pressure block; 56, reciprocating extrusion member; 57, rotating shaft; 58, sliding ring; 59, rotating gear; 510, rack; 6, spiral feed shaft; 7, second drive gear; 8, transition gear; 9, incomplete gear; 10, discharge pipe. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] like Figure 1-8 As shown; Embodiment 1 of the present invention is; A preparation device for a conductive paste for a lithium-ion battery comprises a grinding box 1, two grinding rollers 2 are rotatably connected between opposite side walls of an inner cavity of the grinding box 1, a feed trough 3 is provided on the top of the grinding box 1, an openable and liftable pressing mechanism 4 is installed between the opposite side walls of the feed trough 3, and the bottom of the pressing mechanism 4 is conical and faces the gap between the two grinding rollers 2, and a feeding mechanism 5 is installed on the top of the grinding box 1; The feeding mechanism 5 includes a box body 51 fixed on the top of the grinding box 1, and a reciprocating sliding driving member 52 is installed between the opposite side walls of the inner cavity of the box body 51, and a retractable feeding pipe assembly 53 is installed on the reciprocating sliding driving member 52. Rectangular grooves 54 with semicircular ends are symmetrically opened on the opposite side walls of the box body 51. The two ends of the rectangular groove 54 are set to be semicircular to play a role of smooth transition. A pressing block 55 cooperating with the pressing mechanism 4 is installed on the outer wall of the telescopic end of the feeding pipe assembly 53, and the opposite two ends of the pressing block 55 are respectively slidably connected with the two rectangular grooves 54, and reciprocating extrusion members 56 are symmetrically installed at the opposite two ends of the pressing block 55. When the feeding pipe assembly 53 slides along the lower half of the rectangular groove 54, the feeding pipe assembly 53 is in an extended feeding state and pushes the pressing mechanism 4 to open to both sides through the pressing block 55. When the feeding pipe assembly 53 slides along the upper half of the rectangular groove 54, the feeding pipe assembly 53 is in a non-feeding state and pushes the pressing mechanism 4 to reciprocate and rise and fall to press the material through the reciprocating extrusion member 56.

[0026] In this embodiment, in order to achieve that no material is discharged when the feed pipe assembly is retracted, the feed pipe assembly 53 includes an outer feed pipe 531 fixedly connected to the reciprocating sliding drive member 52, the inner cavity at the bottom of the outer feed pipe 531 is sealed and slidably connected to the inner feed pipe 532, and the bottom of the inner feed pipe 532 is a closed shape, a transverse axis 533 is installed in the inner cavity of the outer feed pipe 531, and a blocking rod 534 inserted into the inner feed pipe 532 is installed at the bottom of the transverse axis 533, and the shape of the blocking rod 534 is adapted to the bottom shape of the inner feed pipe 532. When the inner feed pipe 532 is retracted, the blocking rod 534 is inserted into the bottom of the inner feed pipe 532 and blocks the inner feed pipe 53 2. The pressing block 55 is fixedly connected to the outer wall of the inner feed pipe 532. The outer wall of the inner feed pipe 532 is sleeved with a first spring 535, and the first spring 535 is located between the top of the pressing block 55 and the bottom of the outer feed pipe 531, wherein the extension and retraction of the feed pipe is achieved by the mutual sliding of the inner feed pipe and the outer feed pipe, and when the inner feed pipe slides upward and contracts, the bottom of the blocking rod can be inserted into the closing inner wall of the inner feed pipe, so that the inner feed pipe forms a closed structure, so that no slurry will flow out, and the inner feed pipe is provided with a closing structure so that the inner diameter of the upper end of the inner feed pipe can be larger than the inner diameter of the bottom, thereby ensuring that the blocking rod will not affect the discharge of the slurry when it is at the upper end of the inner feed pipe.

[0027] In this embodiment, the reciprocating sliding drive member 52 includes two reciprocating screw rods 521, and the outer walls of the two reciprocating screw rods 521 are threadedly connected with a slider 522. The outer wall of the fixed end of the feed pipe assembly 53 passes through the slider 522, and the outer walls of one end of the two reciprocating screw rods 521 pass through the side wall of the box body 51 and are connected through a first belt transmission member 523. A driving motor 524 is installed on the grinding box 1, and the driving motor 524 is connected to a reciprocating screw rod 521 and a grinding roller 2 through a second belt transmission member 525, wherein the rotation of the driving motor can drive the two reciprocating screw rods to rotate synchronously, thereby driving the slider and the feed pipe assembly to slide reciprocatingly, and the length of the reciprocating screw rod is greater than the distance between the two ends of the rectangular groove, that is, when the pressing block slides to the end of the rectangular groove, the slider can still continue to slide a distance in the same direction, so that the pressing block can transition up and down through the extension and contraction of the feed pipe assembly, and at the same time, the driving motor can also synchronously drive the two grinding rollers to grind the slurry.

[0028] In this embodiment, the pressing mechanism 4 includes two pressing pieces symmetrically installed on the inner walls of the opposite sides of the feed groove 3, the pressing piece includes a sliding seat 41 with a hollow interior and two mounting shafts 42, the sliding seat 41 is slidably connected with the two mounting shafts 42, and the two mounting shafts 42 pass through the sliding seat 41 and are provided with a limited block, a first inclined surface is provided on the top of a side surface of the two sliding seats 41 close to each other, the pressing block 55 is provided with a second inclined surface that cooperates with the first inclined surface, and a second spring 43 is provided on the outer wall of the mounting shaft 42, and the second spring 43 is provided on the outer wall of the mounting shaft 42. The spring 43 is located between the inner wall of the feed trough 3 and the sliding seat 41. A pressing block 44 is slidably connected between the top and bottom of the inner cavity of the sliding seat 41. The bottoms of the two pressing blocks 44 pass through the bottom of the sliding seat 41, and the bottoms of the two pressing blocks 44 form a conical shape when the two pressing blocks 44 are attached to each other. Two sliding columns 45 are fixed to the top of the pressing block 44. An extrusion strip 46 that cooperates with the reciprocating extrusion piece 56 is installed on the top of the sliding column 45. The outer wall of the sliding column 45 is sleeved with a third spring 47, and the third spring 47 is located at the top of the sliding seat 41. and the extrusion strip 46, wherein when the pressing block transitions from the upper half to the lower half of the rectangular groove, the height of the pressing block can be gradually reduced, so that the pressing block gradually contacts the pressing mechanism, and the second inclined surface of the pressing block cooperates with the first inclined surface of the pressing mechanism to push the pressing mechanism to slide in both directions, thereby opening the pressing mechanism, and until the pressing block slides to the lower half of the rectangular groove, the feed pipe assembly is opened, and finally the feed pipe assembly is fed to the grinding roller, and when the pressing block transitions from the lower half to the upper half of the rectangular groove, the feeding tube assembly is opened. , the pressing block is gradually separated from the pressing mechanism, and then the pressing mechanism returns to its original position under the action of the first spring restoring force, so that the two pressing blocks are closed, and when the pressing block is about to transition from the lower half of the rectangular groove to the upper half, the sealing rod inside the feed pipe assembly is inserted into the closing part of the inner feed pipe to close the feed pipe, and then the reciprocating extrusion part gradually drives the reciprocating extrusion part to reciprocately extrude the extrusion strip and the pressing block during the sliding process of the pressing block along the upper half of the rectangular groove, thereby realizing the reciprocating extrusion of the gap between the grinding rollers by the pressing block.

[0029] In this embodiment, in order to achieve that when the pressing block slides along the upper part of the rectangular groove, the reciprocating extrusion member can be driven to extrude the pressing mechanism, and when the pressing block slides along the lower part of the rectangular groove, the reciprocating extrusion member will not be driven to rotate, so a rotating shaft 57 is rotatably connected to the inner cavity of the pressing block 55, and the rotating shaft 57 is symmetrically rotatably connected to the sliding ring 58 adapted to the rectangular groove 54 at two opposite ends. The reciprocating extrusion member 56 is a cam member, and the rotating shaft 57 is symmetrically fixed with rotating gears 59 at two opposite ends. The inner walls of the box body 51 on both sides are symmetrically fixed with racks 510 that cooperate with the rotating gear 59, and the rack 510 is located above the rectangular groove 54, wherein the sliding ring can rotate along the rectangular groove, and when the sliding ring and the rotating shaft slide to the upper part of the rectangular groove, the rotating gear on the outer wall of the rotating shaft gradually meshes with the rack 510, thereby driving the rotating shaft and the cam member to rotate, so that the cam member can intermittently contact the pressing mechanism below and push the pressing mechanism to slide up and down intermittently, thereby intermittently extruding the material on the grinding roller without affecting the grinding.

[0030] In this embodiment, in order to prevent the pressing block of the pressing mechanism from moving up and down during the opening process, the inner walls on both sides of the box body 51 are symmetrically fixed with limit strips 48 inserted between the bottom of the extrusion strip 46 and the top of the sliding seat 41, and when the two pressing blocks 44 are in contact with each other, the extrusion strip 46 is separated from the contact of the limit strip 48, and when the two pressing blocks 44 are separated from each other, the bottom of the extrusion strip 46 is in contact with the top of the limit strip 48, wherein, when the two pressing blocks are closed, the limit strip will not limit the up and down sliding of the extrusion strip, ensuring that the extrusion strip can slide back and forth up and down under the drive of the reciprocating extrusion member, and when the two pressing blocks are separated, the limit strip is gradually inserted into the bottom of the extrusion strip, so that the limit strip can limit the height position of the extrusion strip, so that no up and down sliding will occur during the movement, and the end of the limit strip is an inclined slope.

[0031] In this embodiment, in order to prevent the installation shaft from affecting the up and down sliding of the pressing block, a strip groove 49 cooperating with the installation shaft 42 is formed through the side wall of the pressing block 44 along the lifting direction of the pressing block 44 .

[0032] In this embodiment, in order to further mix the ground slurry, the cross-section of the bottom of the grinding box 1 is semicircular, and a spiral feeding shaft 6 is rotatably connected between the inner walls on both sides of the bottom of the inner cavity of the grinding box 1. The driving shaft of the spiral feeding shaft 6 passes through the side wall of the grinding box 1 and is installed with a second driving gear 7. The side wall of the grinding box 1 is rotatably connected with a transition gear 8 meshing with the second driving gear 7. The outer walls of the two reciprocating screws 521 are fixed with incomplete gears 9, and the transition gear 8 is located between the two incomplete gears 9 and meshes with the two incomplete gears 9 in turn. A discharge pipe 10 is connected in the middle of the bottom of the grinding box 1, which can mesh with the transition gears in turn when the two incomplete gears rotate, and because the incomplete gears are located on both sides of the transition gears, the transition gears can be driven to rotate back and forth, thereby driving the spiral feeding shaft to feed back and forth, thereby achieving uniform mixing of the slurry, and after mixing, it can be discharged through the discharge pipe.

[0033] In this embodiment, a feed hopper is installed on the top of the box body 51, and the bottom of the feed hopper is connected to the external feed pipe 531 through a retractable hose.

[0034] The specific working process of this embodiment is as follows: Pour the premixed slurry into the feed hopper, then start the drive motor 524, which drives the two reciprocating screws 521 and the two grinding rollers 2 to rotate respectively, and the reciprocating screw 521 drives the slider 522, the feed pipe assembly 53 and the pressing block 55 to slide along the rectangular groove 54; When the pressing block 55 slides along the rectangular groove 54, the sliding rings 58 at both ends of the pressing block 55 can reduce the friction force by rotating relative to the rectangular groove 54, ensuring smoother sliding. Then, when the sliding ring 58 slides to the end of one end of the rectangular groove 54, it gradually slides downward along the semicircular transition section (at this time, the slider 522 still slides in the same direction), synchronously driving the pressing block 55 and the inner feed pipe 532 to slide downward, thereby extending the feed pipe assembly 53, and the pressing block 55 gradually pushes the two sliding seats 41 to slide in a direction away from each other, so that the two pressing blocks 44 gradually open. Until the sliding ring 58 slides to the lower half of the rectangular groove 54, the slider 522 slides to the end of the reciprocating screw 521, and the sealing rod 534 is separated from the closing part of the inner feed pipe 532, so that the slurry in the outer feed pipe 531 can flow into the inner feed pipe 532 and be discharged toward the grinding roller 2. At the same time, as the reciprocating screw 521 continues to rotate, it can drive the slider 522 to slide in the opposite direction (at this time, the sliding ring 58 is in the lower half of the rectangular groove 54), so that the slurry can be evenly distributed on the grinding roller 2, and the grinding roller 2 rotates synchronously to grind the slurry.

[0035] When the slider 522 gradually slides to the end of the other end of the reciprocating screw rod 521, the sliding ring 58 slides to the transition section at the other end of the rectangular groove 54 and gradually slides upward, and when the sliding ring 58 starts to slide upward, it simultaneously drives the inner feed pipe 532 to shrink upward, so that the blocking rod 534 can be inserted into the closing part of the inner feed pipe 532 to stop the discharge, and then as the sliding ring 58 slides upward, the pressing block 55 is gradually separated from the two sliding seats 41, and the two sliding seats 41 return to their original positions under the action of the restoring force of the second spring 43, so that the bottoms of the two pressing blocks 44 are attached to each other and form a conical shape, and then the sliding ring 58 is 8 slides to the upper half of the rectangular groove 54 (at this time, the slider 522 slides to the end of the reciprocating screw 521), so that as the reciprocating screw 521 continues to rotate, the slider 522 can be driven to slide in the opposite direction, and during the sliding process, the rotating gear 59 on the outer wall of the rotating shaft 57 gradually contacts the rack 510, thereby driving the rotating shaft 57 and the cam member to rotate through the rack 510, and then the extrusion bar 46 is reciprocatedly extruded through the cam member, so that the two pressing blocks 44 can slide downward synchronously and squeeze the material on the grinding roller 2, so that the large particle material on the grinding roller 2 can be squeezed into the gap between the two grinding rollers 2 and ground.

[0036] After the sliding ring 58 slides to the end of the rectangular groove 54 again, it slides downward again to open the pressing block 44 and discharge the material from the feed pipe assembly 53, and this reciprocating process is repeated to achieve uninterrupted and efficient grinding of the conductive paste.

[0037] During the grinding process, the incomplete gears 9 on the two grinding rollers 2 can drive the transition gear 8 to rotate in opposite directions in turn, thereby driving the second drive gear 7 and the spiral feed shaft 6 to rotate back and forth, thereby reciprocatingly transporting and mixing the slurry at the bottom of the grinding box 1 to achieve efficient mixing. After the grinding and mixing are completed, the discharge pipe 10 at the bottom is opened for discharge.

[0038] During the opening process of the pressing block 44 , the extrusion bar 46 can gradually contact the limiting bar 48 , so that the height of the extrusion bar 46 is kept fixed through the limiting effect of the limiting bar 48 and does not slide up and down.

[0039] like Figure 1-8 As shown, the second embodiment of the present invention is: A method for preparing a conductive paste for a lithium ion battery comprises the following steps: S1, 1.25 parts by weight of polyvinyl pyrrolidone (PVP-K30) and 93.75 parts by weight of NMP were mixed at a stirring speed of 300 rpm for 20 min, 5 parts by weight of carbon nanotubes were added, and the mixture was dispersed at a stirring speed of 300 rpm for 40 min to obtain a premix; S2. Grind the premix obtained in step S1 in the grinder of Example 1 to obtain an aqueous conductive slurry of oligo-walled carbon nanotubes.

[0040] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixation" and "screw-on" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral one; 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, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0041] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes may be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A device for preparing a conductive paste for lithium-ion batteries, characterized in that: It comprises a grinding box (1), wherein two grinding rollers (2) are rotatably connected between two opposite side walls of an inner cavity of the grinding box (1), a feed trough (3) is provided on the top of the grinding box (1), an openable and liftable pressing mechanism (4) is installed between the inner walls on two opposite sides of the feeding trough (3), and the bottom of the pressing mechanism (4) is conical and faces the gap between the two grinding rollers (2), and a feeding mechanism (5) is installed on the top of the grinding box (1); The feeding mechanism (5) comprises a box body (51) fixed on the top of the grinding box (1), a reciprocating sliding driving member (52) is installed between opposite side walls of the inner cavity of the box body (51), a retractable feeding pipe assembly (53) is installed on the reciprocating sliding driving member (52), rectangular grooves (54) with semicircular ends are symmetrically opened on the opposite side walls of the box body (51), and a pressing block (55) that cooperates with the pressing mechanism (4) is installed on the outer wall of the telescopic end of the feeding pipe assembly (53), and the opposite ends of the pressing block (55) are respectively connected to the two rectangular grooves (54) and the two rectangular grooves (54 ... are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and the two rectangular grooves are respectively connected to the two rectangular grooves (54) and The two pressure blocks (55) are symmetrically connected to each other through the rectangular groove (54), and reciprocating extrusion pieces (56) are symmetrically installed at opposite ends of the pressure block (55). When the feed pipe assembly (53) slides along the lower half of the rectangular groove (54), the feed pipe assembly (53) is in an extended feeding state and pushes the pressure mechanism (4) to open to both sides through the pressure block (55). When the feed pipe assembly (53) slides along the upper half of the rectangular groove (54), the feed pipe assembly (53) is in a non-feeding state and pushes the pressure mechanism (4) to reciprocate and rise and fall to press the material through the reciprocating extrusion piece (56).

2. The device for preparing a conductive paste for lithium-ion batteries according to claim 1, characterized in that: The feed pipe assembly (53) comprises an outer feed pipe (531) fixedly connected to a reciprocating sliding drive member (52); the inner cavity at the bottom of the outer feed pipe (531) is sealingly and slidingly connected to an inner feed pipe (532), and the bottom of the inner feed pipe (532) is in a closed shape; a transverse axis (533) is installed in the inner cavity of the outer feed pipe (531); a blocking rod (534) inserted into the inner feed pipe (532) is installed at the bottom of the transverse axis (533), and the shape of the blocking rod (534) is adapted to the shape of the bottom of the inner feed pipe (532); when the inner feed pipe (532) contracts, the blocking rod (534) is inserted into the bottom of the inner feed pipe (532) and blocks the inner feed pipe (532); and the pressing block (55) is fixedly connected to the outer wall of the inner feed pipe (532).

3. The device for preparing a conductive paste for lithium ion batteries according to claim 2, characterized in that: The outer wall of the inner feed pipe (532) is sleeved with a first spring (535), and the first spring (535) is located between the top of the pressing block (55) and the bottom of the outer feed pipe (531).

4. The device for preparing a conductive paste for lithium-ion batteries according to claim 1, characterized in that: A rotating shaft (57) is rotatably connected to the inner cavity of the pressure block (55), and sliding rings (58) matching the rectangular groove (54) are rotatably connected to both ends of the rotating shaft (57). The reciprocating extrusion member (56) is a cam member, and rotating gears (59) are symmetrically fixedly connected to opposite ends of the rotating shaft (57). Racks (510) matching the rotating gears (59) are symmetrically fixedly connected to the inner walls of opposite sides of the box body (51).

5. The device for preparing a conductive paste for lithium-ion batteries according to claim 1, characterized in that: The pressing mechanism (4) comprises two pressing pieces symmetrically mounted on the inner walls of opposite sides of the feed trough (3), the pressing pieces comprising a sliding seat (41) with a hollow interior and two mounting shafts (42), the sliding seat (41) being slidably connected to the two mounting shafts (42), and the two mounting shafts (42) passing through the sliding seat (41) and provided with a limit block, a first inclined surface being provided at the top of a side surface where the two sliding seats (41) are close to each other, the pressing block (55) being provided with a second inclined surface that cooperates with the first inclined surface, the outer wall of the mounting shaft (42) being provided with a second spring (43), and the second spring (43) being located at the feed trough (3) A pressing block (44) is slidably connected between the inner wall and the sliding seat (41), and between the top and bottom of the inner cavity of the sliding seat (41). The bottoms of the two pressing blocks (44) pass through the bottom of the sliding seat (41), and when the two pressing blocks (44) are in contact with each other, the bottoms form a conical shape. Two sliding columns (45) are fixed to the top of the pressing block (44), and an extrusion strip (46) that cooperates with the reciprocating extrusion piece (56) is installed on the top of the sliding column (45). The outer wall of the sliding column (45) is sleeved with a third spring (47), and the third spring (47) is located between the top of the sliding seat (41) and the extrusion strip (46).

6. The device for preparing a conductive paste for lithium-ion batteries according to claim 5, characterized in that: The inner walls on opposite sides of the box body (51) are symmetrically fixed with limit strips (48) inserted between the bottom of the extrusion strip (46) and the top of the sliding seat (41), and when the two pressing blocks (44) are in contact with each other, the extrusion strip (46) is separated from the contact with the limit strip (48), and when the two pressing blocks (44) are separated from each other, the bottom of the extrusion strip (46) is in contact with the top of the limit strip (48).

7. The device for preparing a conductive paste for lithium-ion batteries according to claim 5, characterized in that: A strip groove (49) is formed on the side wall of the pressing block (44) along the lifting direction of the pressing block (44) and cooperates with the installation shaft (42).

8. The device for preparing a conductive paste for lithium-ion batteries according to claim 1, characterized in that: The reciprocating sliding drive member (52) comprises two reciprocating screw rods (521), the outer walls of the two reciprocating screw rods (521) are threadedly connected to a slider (522), the outer wall of the fixed end of the feed pipe assembly (53) passes through the slider (522), the outer walls of one end of the two reciprocating screw rods (521) pass through the side wall of the box body (51) and are connected through a first belt transmission member (523), and a driving motor (524) is installed on the grinding box (1), and the driving motor (524) is connected to a reciprocating screw rod (521) and a grinding roller (2) through a second belt transmission member (525).

9. The device for preparing a conductive paste for lithium-ion batteries according to claim 8, characterized in that: The bottom cross-section of the grinding box (1) is semicircular, a spiral feed shaft (6) is rotatably connected between the inner walls on both sides of the inner cavity bottom of the grinding box (1), the drive shaft of the spiral feed shaft (6) passes through the side wall of the grinding box (1) and is installed with a second drive gear (7), the side wall of the grinding box (1) is rotatably connected with a transition gear (8) meshing with the second drive gear (7), the outer walls of the two reciprocating screws (521) are fixed with incomplete gears (9), and the transition gear (8) is located between the two incomplete gears (9) and meshes with the two incomplete gears (9) in sequence, and a discharge pipe (10) is connected to the middle of the bottom of the grinding box (1).

10. A method for preparing a conductive paste for lithium ion batteries, characterized in that: The steps include: S1, adding 0.8-1.5 parts by weight of polyvinyl pyrrolidone and 90-95 parts by weight of NMP into a mixer, and mixing them for 15-25 minutes at a stirring speed of 250-350 rpm, then adding 3-7 parts by weight of carbon nanotubes, and dispersing them for 35-50 minutes at a stirring speed of 270-320 rpm to obtain a premix; S2. Grind the premix obtained in step S1 using the preparation device described in any one of claims 1 to 9 to obtain an aqueous conductive slurry of oligo-walled carbon nanotubes.

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