A method and system for preparing lithium iron manganese phosphate positive electrode material

Abstract

The invention discloses a preparation method and system of a lithium iron manganese phosphate positive electrode material, relates to the technical field of electrode material preparation, and aims to solve the technical problem of low efficiency of a LMFP preparation device. The invention comprises a source material mixing mechanism, wherein the raw materials are uniformly mixed in the source material mixing mechanism, and the raw materials after preliminary mixing are secondary mixed and crushed by a ball mill. During the operation of the ball mill, a large number of grinding bodies in the mill will generate continuous impact and friction, and the impact and friction will generate heat, so the uniformly mixed raw materials are preheated, and then sintered in a high-temperature sintering furnace to convert them into lithium iron manganese phosphate materials with a specific crystal structure, and then crushed into finished products with a required particle size by a graded particle size crushing mechanism, and finally sieved and stored by a vibration screening mechanism, thereby significantly improving the preparation efficiency, uniformity and performance of the materials, while reducing energy consumption and cost, and providing strong support for the production of high-performance battery materials.

Description

Technical Field

[0001] The present invention relates to the technical field of electrode material preparation, and more specifically, to a method and system for preparing lithium iron manganese phosphate positive electrode material. Background Art

[0002] As an emerging positive electrode material for power batteries, lithium manganese iron phosphate (LMFP, chemical formula is usually LiFexMn1-xPO4) has attracted extensive attention and research in recent years because it combines the advantages of high safety of lithium iron phosphate (LFP) and high energy density of lithium manganese phosphate (LMP). LMFP can theoretically overcome the bottleneck of low energy density of LFP while maintaining high cycle stability and safety, and is expected to become an important material in the field of power batteries in the future.

[0003] As a traditional preparation method for polyanionic compounds, the solid phase method mainly includes the steps of precursor grinding, heat treatment, secondary grinding and high-temperature calcination. This method has the advantages of low industrial difficulty and high compaction density, but the particle size is large and the distribution is uneven, resulting in poor material consistency, long reaction process and high energy consumption. During the high-temperature calcination process, LMFP particles are prone to agglomeration to form larger particle clusters. These clusters are difficult to effectively disperse in the subsequent crushing process, resulting in reduced crushing efficiency. The LMFP material itself has high hardness and certain toughness, so that more energy input is required to effectively crush it during the crushing process. At the same time, due to the high sintering temperature and severe agglomeration, different levels of crushing and screening are required, such as jaw crushing, roller crushing and ultrafine crushing. After crushing, multiple levels of equipment are required, which leads to the need for enterprises to purchase a variety of equipment, which is relatively expensive and increases energy consumption, which is not conducive to cost reduction and efficiency improvement of enterprises.

[0004] In summary, the problem of low efficiency of preparing LMFP by solid phase method needs to be solved urgently. In view of this, we propose a preparation method and system for lithium iron manganese phosphate positive electrode material. Summary of the invention

[0005] The object of the present invention is to provide a method and system for preparing a lithium iron manganese phosphate positive electrode material to solve the technical problem of low efficiency of a LMFP preparation device.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a method and system for preparing lithium iron manganese phosphate positive electrode material, comprising a source material mixing mechanism, wherein a spiral feeder is provided at the input end of the source material mixing mechanism, and the output end of the source material mixing mechanism is connected to a ball mill through a conveying pipeline A, and the output end of the ball mill is connected to a high-temperature sintering furnace through a conveying pipeline B, and the output end of the high-temperature sintering furnace is connected to a graded particle size crushing mechanism through a belt feeder, and the output end of the graded particle size crushing mechanism is connected to a vibrating screening mechanism;

[0007] Wherein, the vibration screening mechanism is arranged on the support frame, the graded particle size crushing mechanism is arranged at the top of the support frame directly above the vibration screening mechanism, the graded particle size crushing mechanism is provided with a feed port at the top, and a discharge port is provided at the bottom of the graded particle size crushing mechanism, the feed port is connected to the output end of the belt feeder at one end away from the graded particle size crushing mechanism, and the discharge port is connected to the input end of the vibration screening mechanism at one end away from the graded particle size crushing mechanism;

[0008] The graded particle size crushing mechanism includes a driving unit, a bearing shell, a crushing chamber, a crushing disc group, a diameter-changing component, a linkage component and an adjustable tool group, wherein the driving unit is arranged at the top of the supporting frame, the bearing shell is arranged on the supporting frame at a position close to the output end of the driving unit, the crushing chamber is opened inside the bearing shell, the feeding port is arranged at the top of the bearing shell, the discharging port is arranged at the bottom of the bearing shell, the crushing disc group is arranged inside the bearing shell, the diameter-changing component is arranged on the crushing disc group, the linkage component is arranged on the crushing disc group, and the adjustable tool group is arranged on the diameter-changing component in a circular shape with equal spacing;

[0009] The crushing disc group and the adjustable tool group cooperate with the inner wall of the bearing shell to form the crushing chamber, and the variable diameter component and the adjustable tool group form a loose large particle size state and an ultra-fine small particle size state through the linkage component.

[0010] Preferably, the driving unit includes a reduction motor, a coupling and an output shaft, the reduction motor is arranged at the top of the support frame, the output shaft is rotatably inserted on the bearing shell, one end of the coupling is connected to the output end of the reduction motor, and the other end of the coupling is connected to the output shaft.

[0011] Preferably, the crushing disc group includes a rotating disc body, a center hole, a limiting slide groove, a moving rod, an extrusion block and a limiting slide rod, a plurality of the rotating disc bodies are sleeved on the output shaft through the center hole, the limiting slide grooves are arranged on the rotating disc body in a ring shape with equal intervals, the limiting slide grooves extend out of the outer wall of the rotating disc body, the moving rod is movably inserted in the limiting slide groove, the extrusion block is connected to the outer end of the moving rod, the limiting slide rod is connected to the inner end of the moving rod, the reducing assembly is connected to the position of the rotating disc body close to the limiting slide rod, and the linkage assembly is rotatably connected to a plurality of the extrusion blocks.

[0012] Preferably, the variable diameter assembly includes a rotating disk body, an external tooth groove A, a curved groove, a driving gear, a driving rod and a servo motor. The rotating disk body is arranged on the rotating disk body, the external tooth groove A is opened on the outer wall of the rotating disk body, the curved grooves are opened on the rotating disk body in a circular shape with equal intervals, the driving gear is rotatably connected to the rotating disk body at a position close to one side of the rotating disk body, the driving rod passes through the rotating disk body and is connected to the rotating disk body, the output end of the servo motor is connected to the driving rod, the limiting slide rod is slidably connected to the curved groove, one end of the driving gear is meshedly connected to the external tooth groove A, and the other end of the driving gear is meshedly connected to the linkage assembly.

[0013] Preferably, the linkage assembly includes a linkage block, an external tooth groove B, an internal tooth groove, a planetary gear, a rotating connecting rod and a connecting piece. Several of the linkage blocks are rotatably connected to the extrusion block in a ring shape with equal intervals. Several of the linkage blocks are connected by the connecting piece. The external tooth groove B is opened on the outer wall of the linkage block, and the internal tooth groove is opened on the inner wall of the linkage block. The planetary gear is rotatably connected to the extrusion block near the external tooth groove B. The rotating connecting rod passes through the extrusion block and is connected to the planetary gear. The driving gear is meshed and connected to the internal tooth groove on the side away from the external tooth groove A. The planetary gear is meshed and connected to the external tooth groove B, and the adjustable tool set is set on the rotating connecting rod.

[0014] Preferably, built-in grooves are provided on the outer walls at both ends of the linkage block, and the connecting member is provided on the built-in grooves;

[0015] The connecting member comprises a rotating block and a telescopic rod, wherein the rotating block is rotatably connected to the built-in groove, and the telescopic rod is connected to the rotating block.

[0016] Preferably, the adjustable tool group includes a sleeve, a mounting frame, a pin, a center gear and an expansion and contraction tool. The sleeve is symmetrically mounted on the rotating connecting rod, one end of the sleeve is connected to the extrusion block, the mounting frame is mounted on the sleeve, the pin is connected to the mounting frame in a ring shape with equal intervals, the center gear is fixedly mounted on the rotating connecting rod near a position between two symmetrical mounting frames, and the expansion and contraction tool is rotatably mounted on the pin.

[0017] Preferably, the expansion and contraction tool includes a sleeve body, intermittent teeth and a crushing knife body. The sleeve body is rotatably sleeved on the pin shaft, the intermittent teeth are opened on one side of the outer wall of the sleeve body, and the crushing knife body is arranged on the other side of the outer wall of the sleeve body. The sleeve body is meshedly connected to the central gear through the intermittent teeth.

[0018] The present invention also provides a method for preparing a lithium iron manganese phosphate positive electrode material, comprising the following steps:

[0019] S1, raw material mixing operation;

[0020] Firstly, raw materials such as lithium salt, manganese salt, iron salt and phosphate are mixed in proportion and put into the source material mixing mechanism through a spiral feeder for uniform stirring and mixing;

[0021] S2, grinding preheating operation;

[0022] The uniformly mixed raw materials are transported to the inside of the ball mill through the conveying pipe A, driving the ball mill to operate, and the ball mill further mixes and grinds the raw materials. At the same time, the heat generated during the operation performs preliminary preheating and drying treatment on the raw materials.

[0023] S3, adjustment operation;

[0024] S3.1. Determine the specific adjustment state according to the particle size of the required finished particles. If it is necessary to loosen the finished particles with large particle size, the servo motor drives the driving rod to rotate, the driving rod drives the driving gear to rotate, the driving gear engages with the outer tooth groove A of the rotating disk body to make the rotating disk body rotate, and the rotating disk body drives a number of curved grooves arranged in annular shapes with equal intervals to rotate, so that the limiting slide bar slides in the curved groove, the limiting slide bar pulls the moving rod to move in the limiting slide groove, and the moving rod drives the extrusion block to move, so that the crushing disk group is reduced as a whole, releasing the volume of the crushing chamber formed in cooperation with the inner wall of the bearing shell. At the same time, the servo motor drives the driving rod to rotate, the driving rod drives the driving gear to rotate, the driving gear engages with the inner tooth groove of the linkage block, so that the linkage block rotates, the linkage block rotates and drives the outer tooth groove B to rotate, the outer tooth groove B engages and rotates with a number of planetary gears, the planetary gear drives the rotating connecting rod to rotate, the rotating connecting rod drives the central gear to rotate, the central gear engages with the intermittent tooth groove of the sleeve disc body, so that the sleeve disc body drives the fine crushing cutter body to rotate to achieve an inward state;

[0025] S3.2. Determine the specific adjustment state according to the particle size of the required finished particles. If ultra-fine and small-size finished particles are required, the servo motor drives the driving rod to rotate, the driving rod drives the driving gear to rotate, the driving gear engages with the outer tooth groove A of the rotating disk body to rotate the rotating disk body, and the rotating disk body drives a number of circular curved grooves with equal spacing to rotate, so that the limiting slide bar slides in the curved groove, the limiting slide bar pulls the moving rod to move in the limiting slide groove, and the moving rod drives the extrusion block to move, so that the crushing disc group is expanded as a whole, and the volume of the crushing chamber formed by the inner wall of the bearing shell is compressed. At the same time, the servo motor drives the driving rod to rotate, the driving rod drives the driving gear to rotate, the driving gear engages with the inner tooth groove of the linkage block, so that the linkage block rotates, the linkage block rotates and drives the outer tooth groove B to rotate, the outer tooth groove B engages and rotates with a number of planetary gears, the planetary gear drives the rotating connecting rod to rotate, the rotating connecting rod drives the central gear to rotate, the central gear engages with the intermittent tooth groove of the sleeve disc body, so that the sleeve disc body drives the fine crushing cutter body to rotate to achieve the unfolded state;

[0026] S4, crushing operation;

[0027] The reduction motor drives the output shaft to rotate through the coupling, and the output shaft drives the crushing disc group, the reducer assembly, the linkage assembly and the adjustable tool group to rotate as a whole, and the crushing disc group and the adjustable tool group crush the cluster particles;

[0028] S5, screening operation;

[0029] The finished particles after crushing are screened by a vibrating screening mechanism and then stored.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention improves the existing preparation system of lithium iron manganese phosphate positive electrode materials, connects a ball mill through a conveying pipeline A at the output end of a source material mixing mechanism, connects a high-temperature sintering furnace through a conveying pipeline B at the output end of the ball mill, connects a graded particle size crushing mechanism through a belt feeder at the output end of the high-temperature sintering furnace, and connects a graded particle size crushing mechanism at the output end of the graded particle size crushing mechanism to a vibrating screening mechanism. Raw materials such as lithium salt, manganese salt, iron salt and phosphate are uniformly mixed in the source material mixing mechanism, and the raw materials after preliminary mixing are secondary mixed and crushed by a ball mill. During the operation of the ball mill, continuous impact and friction will be generated between a large number of grinding bodies in the mill, and such impact and friction will generate heat, so that the uniformly mixed raw materials are preheated, and then sintered by a high-temperature sintering furnace to convert them into lithium iron manganese phosphate materials with a specific crystal structure, and then crushed to a finished product of a required particle size by a graded particle size crushing mechanism, and finally sieved and stored by a vibrating screening mechanism, which significantly improves the preparation efficiency, uniformity and performance of the materials, while reducing energy consumption and costs, and provides strong support for the production of high-performance battery materials.

[0032] 2. The servo motor of the variable diameter assembly in the present invention drives the driving rod to rotate, the driving rod drives the driving gear to rotate, the driving gear engages with the outer tooth groove A of the rotating disk body to rotate the rotating disk body, the rotating disk body drives a number of curved grooves arranged in a ring shape with equal intervals to rotate, so that the limiting slide bar slides in the curved groove, the limiting slide bar pulls the moving rod to move in the limiting slide groove, the moving rod drives the extrusion block to move, so that the crushing disc group is expanded as a whole, and the volume of the crushing chamber formed by the inner wall of the bearing shell is compressed, so that the particle size of the finished particles can be accurately controlled according to needs, which is very important for improving the energy density, cycle stability and safety of the battery.

[0033] 3. In the present invention, when the servo motor of the variable diameter assembly drives the driving rod to rotate, and the driving rod drives the driving gear to rotate, the driving gear engages with the inner tooth groove of the linkage block, so that the linkage block rotates, and the rotation of the linkage block drives the outer tooth groove B to rotate, and the outer tooth groove B engages and rotates with a number of planetary gears, and the planetary gears drive the rotating connecting rod to rotate, and the rotating connecting rod drives the central gear to rotate. The intermittent tooth groove engagement of the central gear and the sleeve disc body enables the sleeve disc body to drive the fine crushing knife body to rotate to achieve the two states of expansion and retraction, so that the particle size distribution can be further accurately controlled, the crushing efficiency is optimized, which is helpful to optimize the specific surface area and pore structure of the electrode material, and promote the rapid diffusion and efficient transmission of lithium ions. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the overall structure of the system of the present invention.

[0035] Figure 2 It is a schematic diagram of the structure of the grading particle size crushing mechanism and the vibration screening mechanism of the present invention.

[0036] Figure 3 It is a schematic diagram of the internal structure of the graded particle size crushing mechanism of the present invention.

[0037] Figure 4 It is a schematic diagram of the back structure of the grading particle size crushing mechanism of the present invention.

[0038] Figure 5 It is a schematic diagram of the structure of the crushing disc group and the variable diameter assembly of the present invention.

[0039] Figure 6 It is a schematic cross-sectional structure diagram of the graded particle size crushing mechanism of the present invention.

[0040] Figure 7 It is a schematic diagram of the unfolded structural state of the pulverizing disc assembly of the present invention.

[0041] Figure 8 It is a schematic diagram of the unfolded structure of the linkage component of the present invention.

[0042] Fig. 9 It is an enlarged view of point A of the present invention.

[0043] Fig.10 It is a schematic diagram of the structure of the output shaft and the adjustable tool assembly of the present invention.

[0044] Fig.11 It is a schematic cross-sectional view of the output shaft and the adjustable tool assembly of the present invention.

[0045] Fig.12 This is a schematic diagram of the use of the ultra-fine small particle size state of the present invention.

[0046] Description of the numbers in the figure:

[0047] 1. Source material mixing mechanism; 2. Screw feeder; 3. Conveying pipeline A; 4. Ball mill; 5. Conveying pipeline B; 6. High-temperature sintering furnace; 7. Belt feeder; 8. Grading particle size crushing mechanism; 9. Vibration screening mechanism; 10. Feeding port; 11. Discharging port; 12. Support frame;

[0048] 801, driving unit; 802, bearing housing; 803, crushing chamber; 804, crushing disc assembly; 805, variable diameter assembly; 806, linkage assembly; 807, adjustable tool assembly;

[0049] 8011, reduction motor; 8012, coupling; 8013, output shaft;

[0050] 8041, rotating disk; 8042, center hole; 8043, limit slide groove; 8044, moving rod; 8045, extrusion block; 8046, limit slide rod;

[0051] 8051, rotating disk; 8052, external tooth groove A; 8053, curved groove; 8054, driving gear; 8055, driving rod; 8056, servo motor;

[0052] 8061, linkage block; 8062, external tooth groove B; 8063, internal tooth groove; 8064, planetary gear; 8065, rotating connecting rod; 8066, connecting piece; 8067, built-in groove; 8068, rotating block; 8069, telescopic rod;

[0053] 8071. sleeve; 8072. mounting frame; 8073. pin shaft; 8074. center gear; 8075. expansion and contraction tool; 8076. sleeve body; 8077. intermittent tooth groove; 8078. crushing tool body. DETAILED DESCRIPTION

[0054] like Figures 1 to 12 As shown, the present invention relates to a method and system for preparing a lithium iron manganese phosphate positive electrode material, comprising a source material mixing mechanism 1, wherein a spiral feeder 2 is provided at the input end of the source material mixing mechanism 1, a ball mill 4 is connected to the output end of the source material mixing mechanism 1 through a conveying pipeline A3, a high-temperature sintering furnace 6 is connected to the output end of the ball mill 4 through a conveying pipeline B5, a graded particle size crushing mechanism 8 is connected to the output end of the high-temperature sintering furnace 6 through a belt feeder 7, and a vibration screening mechanism 9 is connected to the output end of the graded particle size crushing mechanism 8;

[0055] Among them, the vibration screening mechanism 9 is arranged on the support frame 12, the graded particle size crushing mechanism 8 is arranged at the top of the support frame 12 and is located directly above the vibration screening mechanism 9, the graded particle size crushing mechanism 8 is provided with a feed port 10 at the top, and a discharge port 11 at the bottom of the graded particle size crushing mechanism 8, the feed port 10 is connected to the output end of the belt feeder 7 at one end away from the graded particle size crushing mechanism 8, and the discharge port 11 is connected to the input end of the vibration screening mechanism 9 at one end away from the graded particle size crushing mechanism 8;

[0056] The graded particle size crushing mechanism 8 includes a driving unit 801, a bearing shell 802, a crushing chamber 803, a crushing disc group 804, a diameter reducing assembly 805, a linkage assembly 806 and an adjustable tool group 807. The driving unit 801 is arranged at the top of the support frame 12, the bearing shell 802 is arranged on the support frame 12 near the output end of the driving unit 801, the crushing chamber 803 is opened inside the bearing shell 802, the feed inlet 10 is arranged at the top of the bearing shell 802, the discharge port 11 is arranged at the bottom of the bearing shell 802, the crushing disc group 804 is arranged inside the bearing shell 802, the diameter reducing assembly 805 is arranged on the crushing disc group 804, the linkage assembly 806 is arranged on the crushing disc group 804, and the adjustable tool group 807 is arranged on the diameter reducing assembly 805 in a circular shape with equal spacing;

[0057] Among them, the crushing disc group 804 and the adjustable tool group 807 cooperate with the inner wall of the supporting shell 802 to form a crushing chamber 803, and the variable diameter component 805 and the adjustable tool group 807 form a loose large particle size state and an ultra-fine small particle size state through the linkage component 806.

[0058] The present invention improves the existing preparation system of lithium iron manganese phosphate positive electrode material, connects the output end of the source material mixing mechanism 1 to the ball mill 4 through the conveying pipeline A3, connects the output end of the ball mill 4 to the high temperature sintering furnace 6 through the conveying pipeline B5, connects the output end of the high temperature sintering furnace 6 to the graded particle size crushing mechanism 8 through the belt feeder 7, and connects the output end of the graded particle size crushing mechanism 8 to the vibration screening mechanism 9, and evenly mixes raw materials such as lithium salt, manganese salt, iron salt and phosphate in the source material mixing mechanism 1, and performs secondary mixing and crushing on the raw materials after preliminary mixing by using the ball mill 4. During the operation of the mill 4, due to the constant impact and friction between the large number of grinding bodies in the mill, this impact and friction will generate heat, which will preliminarily preheat the mixed raw materials, and then sinter them in the high-temperature sintering furnace 6 to convert them into lithium iron manganese phosphate materials with a specific crystal structure. They are then crushed into finished products of the required particle size by the graded particle size crushing mechanism 8, and finally screened and stored by the vibration screening mechanism 9, which significantly improves the preparation efficiency, uniformity and performance of the materials, while reducing energy consumption and costs, providing strong support for the production of high-performance battery materials.

[0059] In the embodiment of the present invention, the driving unit 801 includes a reduction motor 8011, a coupling 8012 and an output shaft 8013. The reduction motor 8011 is arranged at the top of the support frame 12, and the output shaft 8013 is rotatably inserted in the bearing shell 802. One end of the coupling 8012 is connected to the output end of the reduction motor 8011, and the other end of the coupling 8012 is connected to the output shaft 8013. In the present invention, the reduction motor 8011 of the driving unit 801 drives the output shaft 8013 to rotate through the coupling 8012, and the output shaft 8013 drives the crushing disc group 804, the diameter reducing assembly 805, the linkage assembly 806 and the adjustable tool group 807 to rotate as a whole. The crushing disc group 804 and the adjustable tool group 807 cooperate with the inner wall of the bearing shell 802 to form a crushing chamber 803 to crush the finished material body.

[0060] In an embodiment of the present invention, the crushing disc group 804 includes a rotating disc body 8041, a center hole 8042, a limiting slide groove 8043, a moving rod 8044, an extrusion block 8045 and a limiting slide bar 8046. Several rotating disc bodies 8041 are sleeved on the output shaft 8013 through the center hole 8042. The limiting slide grooves 8043 are arranged on the rotating disc body 8041 in a ring-shaped and equidistant manner. The limiting slide grooves 8043 extend out of the outer wall of the rotating disc body 8041. The moving rod 8044 is movably inserted in the limiting slide groove 8043. The extrusion block 8045 is connected to the outer end of the moving rod 8044. The limiting slide bar 8046 is connected to the inner end of the moving rod 8044. The reducing assembly 805 is connected to the rotating disc body 8041 near the limiting slide bar 8046. The linkage assembly 806 is rotatably connected to several extrusion blocks 8045.

[0061] The reducing assembly 805 includes a rotating disk body 8051, an outer tooth groove A8052, a curved groove 8053, a driving gear 8054, a driving rod 8055 and a servo motor 8056. The rotating disk body 8051 is arranged on the rotating disk body 8041, the outer tooth groove A8052 is opened on the outer wall of the rotating disk body 8051, and the curved grooves 8053 are opened on the rotating disk body 8051 in a ring-shaped and equidistant manner. The driving gear 8054 is rotatably connected to the rotating disk body 8041 at a position close to one side of the rotating disk body 8051, the driving rod 8055 passes through the rotating disk body 8041 and is connected to the rotating disk body 8051, the output end of the servo motor 8056 is connected to the driving rod 8055, the limiting slide bar 8046 is slidably connected to the curved groove 8053, one end of the driving gear 8054 is meshedly connected to the outer tooth groove A8052, and the other end of the driving gear 8054 is meshedly connected to the linkage assembly 806.

[0062] The servo motor 8056 of the variable diameter assembly 805 in the present invention drives the driving rod 8055 to rotate, and the driving rod 8055 drives the driving gear 8054 to rotate. The driving gear 8054 engages with the outer tooth groove A8052 of the rotating disk body 8051 to rotate the rotating disk body 8051, and the rotating disk body 8051 drives a plurality of curved grooves 8053 arranged in a ring shape with equal intervals to rotate, so that the limiting slide bar 8046 slides in the curved groove 8053, and the limiting slide bar 8046 pulls the moving rod 8044 to move in the limiting slide groove 8043, and the moving rod 8044 drives the extrusion block 8045 to move, so that the crushing disk group 804 is expanded as a whole, and the volume of the crushing chamber 803 formed by cooperating with the inner wall of the bearing shell 802 is compressed, so that the particle size of the finished particles can be accurately controlled according to demand, which is very important for improving the energy density, cycle stability and safety of the battery.

[0063] In the embodiment of the present invention, the linkage assembly 806 includes a linkage block 8061, an outer tooth groove B8062, an inner tooth groove 8063, a planetary gear 8064, a rotating connecting rod 8065 and a connecting piece 8066. A plurality of linkage blocks 8061 are rotatably connected to the extrusion block 8045 in an annular shape with equal spacing. A plurality of linkage blocks 8061 are connected by connecting pieces 8066. The outer tooth groove B8062 is provided on the outer wall of the linkage block 8061, and the inner tooth groove 8063 is provided on the outer wall of the linkage block 8061. On the inner wall of the linkage block 8061, the planetary gear 8064 is rotatably connected to the extrusion block 8045 near the outer tooth groove B8062, the rotating connecting rod 8065 passes through the extrusion block 8045 and is connected to the planetary gear 8064, the driving gear 8054 is meshedly connected to the inner tooth groove 8063 on the side away from the outer tooth groove A8052, the planetary gear 8064 is meshedly connected to the outer tooth groove B8062, and the adjustable tool group 807 is sleeved on the rotating connecting rod 8065.

[0064] Built-in grooves 8067 are opened on the outer walls at both ends of the linkage block 8061, and the connecting member 8066 is arranged on the built-in groove 8067; the connecting member 8066 includes a rotating block 8068 and a telescopic rod 8069, the rotating block 8068 is rotatably connected to the built-in groove 8067, and the telescopic rod 8069 is connected to the rotating block 8068.

[0065] In the present invention, when the servo motor 8056 of the variable diameter assembly 805 drives the driving rod 8055 to rotate, and the driving rod 8055 drives the driving gear 8054 to rotate, the driving gear 8054 meshes with the inner tooth groove 8063 of the linkage block 8061, so that the linkage block 8061 rotates, and the linkage block 8061 rotates to drive the outer tooth groove B8062 to rotate, and the outer tooth groove B8062 meshes with a plurality of planetary gears 8064 to rotate, and the planetary gears 8064 drive the rotating connecting rod 8065 to rotate, and the rotating connecting rod 8065 drives the rotating connecting rod 8065 to rotate. The movable adjustable tool group 807 rotates to switch the expansion and retraction of the tool. When the extrusion block 8045 moves, the telescopic rods 8069 on the built-in slots 8067 of the plurality of linkage blocks 8061 connect them as a whole. One of the rotating blocks 8068 is rotatably connected to the top of one of the built-in slots 8067, and the other adjacent rotating block 8068 is rotatably connected to the bottom of the other built-in slot 8067. The two ends of the telescopic rod 8069 are respectively connected to the two rotating blocks 8068, so that the plurality of linkage blocks 8061 are connected as shown in FIG. Figure 8 and Fig. 9 As shown, a separated transmission state can be achieved.

[0066] It is worth noting that Figure 5 As shown, when the driving gear 8054 rotates, it will simultaneously engage with the outer tooth grooves A8052 and the inner tooth grooves 8063 on both sides to drive the rotating disk 8051 and the linkage block 8061 to rotate. Since the transmission ratio of the outer tooth grooves B8062 and the planetary gear 8064 is greater than that of the driving gear 8054 and the outer tooth grooves A8052, the driving gear 8054 will not be unable to drive the linkage block 8061.

[0067] As another embodiment of the present invention, the adjustable tool group 807 includes a sleeve 8071, a mounting frame 8072, a pin 8073, a center gear 8074 and an expansion and contraction tool 8075. The sleeve 8071 is symmetrically sleeved on the rotating connecting rod 8065, one end of the sleeve 8071 is connected to the extrusion block 8045, the mounting frame 8072 is sleeved on the sleeve 8071, the pin 8073 is connected to the mounting frame 8072 in a ring shape with equal intervals, the center gear 8074 is fixedly sleeved on the rotating connecting rod 8065 near the position between the two symmetrical mounting frames 8072, and the expansion and contraction tool 8075 is rotatably sleeved on the pin 8073.

[0068] The expansion and contraction tool 8075 includes a sleeve body 8076, intermittent teeth 8077 and a crushing knife body 8078. The sleeve body 8076 is rotatably sleeved on the pin shaft 8073. The intermittent teeth 8077 are opened on one side of the outer wall of the sleeve body 8076, and the crushing knife body 8078 is arranged on the other side of the outer wall of the sleeve body 8076. The sleeve body 8076 is meshedly connected to the central gear 8074 through the intermittent teeth 8077.

[0069] In the present invention, when the servo motor 8056 of the variable diameter component 805 drives the driving rod 8055 to rotate, and the driving rod 8055 drives the driving gear 8054 to rotate, the driving gear 8054 engages with the inner tooth groove 8063 of the linkage block 8061, so that the linkage block 8061 rotates, and the rotation of the linkage block 8061 drives the outer tooth groove B8062 to rotate, and the outer tooth groove B8062 engages and rotates with a plurality of planetary gears 8064, and the planetary gear 8064 drives the rotating connecting rod 8065 to rotate, and the rotating connecting rod 8065 drives the central gear 8074 to rotate, and the central gear 8074 engages with the intermittent tooth groove 8077 of the sleeve disc body 8076, so that the sleeve disc body 8076 drives the fine crushing knife body 8078 to rotate to realize the two states of expansion and retraction, so as to further accurately control the particle size distribution, optimize the crushing efficiency, help optimize the specific surface area and pore structure of the electrode material, and promote the rapid diffusion and efficient transmission of lithium ions.

[0070] Working principle: This embodiment provides a method for using a system for preparing a lithium iron manganese phosphate positive electrode material, comprising the following steps:

[0071] S1, raw material mixing operation;

[0072] Firstly, raw materials such as lithium salt, manganese salt, iron salt and phosphate are mixed in proportion and put into the source material mixing mechanism 1 through the spiral feeder 2 for uniform stirring and mixing;

[0073] S2, grinding preheating operation;

[0074] The uniformly mixed raw materials are transported to the inside of the ball mill 4 through the conveying pipe A3, and the ball mill 4 is driven to operate. The ball mill 4 further mixes and grinds the raw materials. At the same time, the heat generated during the operation performs preliminary preheating and drying treatment on the raw materials.

[0075] S3, adjustment operation;

[0076] S3.1. Determine the specific adjustment state according to the particle size of the desired finished particles. If it is necessary to loosen the finished particles with large particle size, the servo motor 8056 drives the driving rod 8055 to rotate, and the driving rod 8055 drives the driving gear 8054 to rotate. The driving gear 8054 engages with the outer tooth groove A8052 of the rotating disk body 8051 to rotate the rotating disk body 8051. The rotating disk body 8051 drives a number of curved grooves 8053 arranged at equal intervals in an annular shape to rotate, so that the limiting slide bar 8046 slides in the curved groove 8053, the limiting slide bar 8046 pulls the moving rod 8044 to move in the limiting slide groove 8043, and the moving rod 8044 drives the extrusion block 8045 to move, so that the crushing disk group 804 is reduced as a whole, and the crushing disk group 804 is released from the bearing shell 8051. 02 The volume of the crushing chamber 803 is formed by the inner wall of the servo motor 8056. At the same time, the servo motor 8056 drives the driving rod 8055 to rotate, and the driving rod 8055 drives the driving gear 8054 to rotate. The driving gear 8054 meshes with the inner tooth groove 8063 of the linkage block 8061, so that the linkage block 8061 rotates, and the rotation of the linkage block 8061 drives the outer tooth groove B8062 to rotate. The outer tooth groove B8062 meshes and rotates with a plurality of planetary gears 8064. The planetary gear 8064 drives the rotating connecting rod 8065 to rotate, and the rotating connecting rod 8065 drives the central gear 8074 to rotate. The central gear 8074 meshes with the intermittent tooth groove 8077 of the sleeve disc body 8076, so that the sleeve disc body 8076 drives the fine crushing knife body 8078 to rotate to achieve an inward state.

[0077] S3.2. Determine the specific adjustment state according to the particle size of the desired finished particles. If ultra-fine and small-size finished particles are required, the servo motor 8056 drives the driving rod 8055 to rotate, and the driving rod 8055 drives the driving gear 8054 to rotate. The driving gear 8054 engages with the outer tooth groove A8052 of the rotating disk 8051 to rotate the rotating disk 8051. The rotating disk 8051 drives a number of curved grooves 8053 arranged at equal intervals in a ring shape to rotate, so that the limiting slide bar 8046 slides in the curved groove 8053, the limiting slide bar 8046 pulls the moving rod 8044 to move in the limiting slide groove 8043, and the moving rod 8044 drives the extrusion block 8045 to move, so that the crushing disk group 804 is expanded as a whole, compressing and supporting the shell. The volume of the crushing chamber 803 formed by the inner wall of 802, at the same time, the servo motor 8056 drives the driving rod 8055 to rotate, the driving rod 8055 drives the driving gear 8054 to rotate, the driving gear 8054 is engaged with the inner tooth groove 8063 of the linkage block 8061, so that the linkage block 8061 rotates, the linkage block 8061 rotates to drive the outer tooth groove B8062 to rotate, the outer tooth groove B8062 is engaged and rotated with a plurality of planetary gears 8064, the planetary gear 8064 drives the rotating connecting rod 8065 to rotate, the rotating connecting rod 8065 drives the central gear 8074 to rotate, the central gear 8074 is engaged with the intermittent tooth groove 8077 of the sleeve disc body 8076, so that the sleeve disc body 8076 drives the fine crushing knife body 8078 to rotate to realize the unfolded state;

[0078] S4, crushing operation;

[0079] The reduction motor 8011 drives the output shaft 8013 to rotate through the coupling 8012, and the output shaft 8013 drives the crushing disc group 804, the diameter reducing assembly 805, the linkage assembly 806 and the adjustable tool group 807 to rotate as a whole, and the crushing disc group 804 and the adjustable tool group 807 crush the cluster particles;

[0080] S5, screening operation;

[0081] The crushed finished particles are screened by the vibrating screening mechanism 9 and then stored.

[0082] The embodiments of the present invention disclose preferred embodiments, but are not limited thereto. A person skilled in the art can easily understand the spirit of the present invention based on the above embodiments and make different extensions and changes. However, as long as they do not deviate from the spirit of the present invention, they are all within the protection scope of the present invention.

Claims

1. A system for preparing lithium iron manganese phosphate positive electrode material, characterized in that: It comprises a source material mixing mechanism (1), wherein the input end of the source material mixing mechanism (1) is provided with a screw feeder (2), the output end of the source material mixing mechanism (1) is connected to a ball mill (4) via a conveying pipeline A (3), the output end of the ball mill (4) is connected to a high-temperature sintering furnace (6) via a conveying pipeline B (5), the output end of the high-temperature sintering furnace (6) is connected to a graded particle size crushing mechanism (8) via a belt feeder (7), and the output end of the graded particle size crushing mechanism (8) is connected to a vibration screening mechanism (9); The vibrating screening mechanism (9) is arranged on a support frame (12), the graded particle size crushing mechanism (8) is arranged at the top of the support frame (12) and is located directly above the vibrating screening mechanism (9), the graded particle size crushing mechanism (8) is provided with an inlet (10) at the top, and a discharge port (11) at the bottom, the inlet (10) is connected to the output end of the belt feeder (7) at one end away from the graded particle size crushing mechanism (8), and the discharge port (11) is connected to the input end of the vibrating screening mechanism (9) at one end away from the graded particle size crushing mechanism (8); The graded particle size crushing mechanism (8) comprises a driving unit (801), a bearing shell (802), a crushing chamber (803), a crushing disc group (804), a diameter-changing component (805), a linkage component (806) and an adjustable tool group (807), wherein the driving unit (801) is arranged at the top of the support frame (12), the bearing shell (802) is arranged at a position on the support frame (12) close to the output end of the driving unit (801), and the crushing chamber (803) is opened at the bearing shell (802). Inside the shell (802), the feed port (10) is arranged at the top end of the bearing shell (802), the discharge port (11) is arranged at the bottom end of the bearing shell (802), the crushing disc group (804) is arranged inside the bearing shell (802), the diameter-changing component (805) is arranged on the crushing disc group (804), the linkage component (806) is arranged on the crushing disc group (804), and the adjustable tool group (807) is arranged in a circular shape at equal intervals on the diameter-changing component (805); The crushing disc set (804) and the adjustable cutter set (807) cooperate with the inner wall of the bearing shell (802) to form the crushing chamber (803); The driving unit (801) comprises a reduction motor (8011), a coupling (8012) and an output shaft (8013); the reduction motor (8011) is arranged at the top end of the support frame (12); the output shaft (8013) is rotatably inserted on the bearing shell (802); one end of the coupling (8012) is connected to the output end of the reduction motor (8011); and the other end of the coupling (8012) is connected to the output shaft (8013); The crushing disc assembly (804) comprises a rotating disc body (8041), a center hole (8042), a limiting slide groove (8043), a moving rod (8044), an extrusion block (8045) and a limiting slide rod (8046); a plurality of the rotating disc bodies (8041) are sleeved on the output shaft (8013) through the center hole (8042); the limiting slide grooves (8043) are arranged on the rotating disc body (8041) in a circular shape and at equal intervals; the limiting slide grooves (8043) extend out of the rotating disc body (8041); The outer wall of the disk body (8041), the moving rod (8044) is movably inserted in the limiting slide groove (8043), the extrusion block (8045) is connected to the outer end of the moving rod (8044), the limiting slide bar (8046) is connected to the inner end of the moving rod (8044), the diameter reducing component (805) is connected to the position of the rotating disk body (8041) close to the limiting slide bar (8046), and the linkage component (806) is rotatably connected to a plurality of the extrusion blocks (8045); The diameter reducing assembly (805) comprises a rotating disc (8051), an external tooth groove A (8052), a curved groove (8053), a driving gear (8054), a driving rod (8055) and a servo motor (8056); the rotating disc (8051) is arranged on the rotating disc (8041); the external tooth groove A (8052) is formed on the outer wall of the rotating disc (8051); the curved groove (8053) is formed on the rotating disc (8051) in a circular shape and is evenly spaced; the driving gear (8054) is rotatably connected to the rotating disc (8041); 8041) is located near one side of the rotating disk (8051), the driving rod (8055) passes through the rotating disk (8041) and is connected to the rotating disk (8051), the output end of the servo motor (8056) is connected to the driving rod (8055), the limiting sliding rod (8046) is slidably connected to the curved groove (8053), one end of the driving gear (8054) is meshedly connected to the outer tooth groove A (8052), and the other end of the driving gear (8054) is meshedly connected to the linkage assembly (806); The linkage assembly (806) comprises a linkage block (8061), an outer tooth groove B (8062), an inner tooth groove (8063), a planetary gear (8064), a rotating connecting rod (8065) ​​and a connecting piece (8066); a plurality of the linkage blocks (8061) are rotatably connected to the extrusion block (8045) in an annular shape and at equal intervals; a plurality of the linkage blocks (8061) are connected via the connecting piece (8066); the outer tooth groove B (8062) is provided on the outer wall of the linkage block (8061); and the inner tooth groove (8063) is provided on the linkage block (8061). On the inner wall, the planetary gear (8064) is rotatably connected to the position of the extrusion block (8045) close to the outer tooth groove B (8062), the rotating connecting rod (8065) ​​passes through the extrusion block (8045) and is connected to the planetary gear (8064), the driving gear (8054) is meshedly connected to the inner tooth groove (8063) at a side away from the outer tooth groove A (8052), the planetary gear (8064) is meshedly connected to the outer tooth groove B (8062), and the adjustable tool assembly (807) is sleeved on the rotating connecting rod (8065); The adjustable tool assembly (807) comprises a sleeve (8071), a mounting frame (8072), a pin (8073), a central gear (8074) and an expansion and contraction tool (8075); the sleeve (8071) is symmetrically sleeved on the rotating connecting rod (8065); one end of the sleeve (8071) is connected to the extrusion block (8045); the mounting frame (8072) is sleeved on the sleeve (8071); the pin (8073) is connected to the mounting frame (8072) in an annular shape with equal spacing; the central gear (8074) is fixedly sleeved on the rotating connecting rod (8065) ​​at a position close to two symmetrical mounting frames (8072); and the expansion and contraction tool (8075) is rotatably sleeved on the pin (8073); The expansion and contraction tool (8075) comprises a sleeve body (8076), intermittent tooth grooves (8077) and a crushing knife body (8078); the sleeve body (8076) is rotatably sleeved on the pin shaft (8073); the intermittent tooth grooves (8077) are provided on one side of the outer wall of the sleeve body (8076); the crushing knife body (8078) is provided on the other side of the outer wall of the sleeve body (8076); the sleeve body (8076) is meshedly connected to the central gear (8074) via the intermittent tooth grooves (8077).

2. A system for preparing a lithium iron manganese phosphate positive electrode material according to claim 1, characterized in that: Built-in grooves (8067) are provided on the outer walls at both ends of the linkage block (8061), and the connecting member (8066) is arranged on the built-in grooves (8067).

3. A system for preparing a lithium iron manganese phosphate positive electrode material according to claim 2, characterized in that: The connecting member (8066) comprises a rotating block (8068) and a telescopic rod (8069), wherein the rotating block (8068) is rotatably connected to the built-in groove (8067), and the telescopic rod (8069) is connected to the rotating block (8068).

4. A method for preparing a lithium iron manganese phosphate positive electrode material using the preparation system for the lithium iron manganese phosphate positive electrode material according to claim 3, the preparation method comprising the following steps: S1, raw material mixing operation; Firstly, lithium salt, manganese salt, iron salt and phosphate raw materials are mixed in proportion and then fed into a source material mixing mechanism (1) through a spiral feeder (2) for uniform stirring and mixing; S2, grinding preheating operation; The uniformly mixed raw materials are transported to the inside of the ball mill (4) through the transport pipe A (3), and the ball mill (4) is driven to operate. The ball mill (4) further mixes and grinds the raw materials into fine powder. At the same time, the heat generated during the operation performs preliminary preheating and drying treatment on the raw materials. S3, adjustment operation; S3.

1. The specific adjustment state is determined according to the particle size of the desired finished particles. If it is necessary to loosen the finished particles with large particle size, the servo motor (8056) drives the driving rod (8055) to rotate, and the driving rod (8055) drives the driving gear (8054) to rotate. The driving gear (8054) engages with the outer tooth groove A (8052) of the rotating disk body (8051) to rotate the rotating disk body (8051). The rotating disk body (8051) drives a plurality of circular curved grooves (8053) arranged at equal intervals to rotate, so that the limiting slide bar (8046) slides in the curved groove (8053). The limiting slide bar (8046) pulls the moving rod (8044) to move in the limiting slide groove (8043). The moving rod (8044) drives the extrusion block (8045) to move, so that the crushing disk group (804) is reduced as a whole, and the crushing disk group (804) is released from the bearing shell (802). The volume of the crushing chamber (803) is formed by the wall, and at the same time, the servo motor (8056) drives the driving rod (8055) to rotate, the driving rod (8055) drives the driving gear (8054) to rotate, the driving gear (8054) meshes with the inner tooth groove (8063) of the linkage block (8061), so that the linkage block (8061) rotates, the linkage block (8061) rotates to drive the outer tooth groove B (8062) to rotate, the outer tooth groove B (8062) meshes with a plurality of planetary gears (8064) to rotate, the planetary gear (8064) drives the rotating connecting rod (8065) ​​to rotate, the rotating connecting rod (8065) ​​drives the central gear (8074) to rotate, the central gear (8074) meshes with the intermittent tooth groove (8077) of the sleeve disc body (8076), so that the sleeve disc body (8076) drives the fine crushing knife body (8078) to rotate to achieve an inward state; S3.

2. The specific adjustment state is determined according to the particle size of the desired finished particles. If ultra-fine and small-size finished particles are required, the servo motor (8056) drives the driving rod (8055) to rotate, and the driving rod (8055) drives the driving gear (8054) to rotate. The driving gear (8054) engages with the outer tooth groove A (8052) of the rotating disk body (8051) to rotate the rotating disk body (8051). The rotating disk body (8051) drives a plurality of circular curved grooves (8053) arranged at equal intervals to rotate, so that the limiting slide bar (8046) slides in the curved groove (8053). The limiting slide bar (8046) pulls the moving rod (8044) to move in the limiting slide groove (8043). The moving rod (8044) drives the extrusion block (8045) to move, so that the crushing disk group (804) is expanded as a whole, compressing the bearing shell (802). The inner wall cooperates to form a volume of the crushing chamber (803); at the same time, the servo motor (8056) drives the driving rod (8055) to rotate, the driving rod (8055) drives the driving gear (8054) to rotate, the driving gear (8054) meshes with the inner tooth groove (8063) of the linkage block (8061), so that the linkage block (8061) rotates, the linkage block (8061) rotates to drive the outer tooth groove B (8062) to rotate, the outer tooth groove B (8062) meshes with a plurality of planetary gears (8064) to rotate, the planetary gear (8064) drives the rotating connecting rod (8065) ​​to rotate, the rotating connecting rod (8065) ​​drives the central gear (8074) to rotate, the central gear (8074) meshes with the intermittent tooth groove (8077) of the sleeve disc body (8076), so that the sleeve disc body (8076) drives the fine crushing knife body (8078) to rotate to achieve the unfolded state; S4, crushing operation; The reduction motor (8011) drives the output shaft (8013) to rotate via the coupling (8012), and the output shaft (8013) drives the crushing disc group (804), the diameter reducing assembly (805), the linkage assembly (806) and the adjustable tool group (807) to rotate as a whole, and the crushing disc group (804) and the adjustable tool group (807) crush the cluster particles; S5, screening operation; The finished particles after pulverization are screened by a vibrating screening mechanism (9) and then stored.

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