Sintering device for preparing lithium manganese iron phosphate by solid phase method

Abstract

The utility model discloses a sintering device for preparing lithium manganese iron phosphate by a solid phase method, and relates to the technical field of lithium manganese iron phosphate. The sintering device comprises a heat preservation heating box, a sintering box and a sealing cover, a plurality of material pushing air cylinders are clamped to one end of the heat preservation heating box, the sintering box is clamped to one end of the top of the heat preservation heating box in a penetrating mode, a plurality of ventilation heat conduction partition plates are fixedly welded in the sintering box, and the sealing cover is fixedly clamped to the top of the sintering box. A filtering assembly is arranged at the top of the sealing cover, and an air pump is clamped to the top of the filtering assembly in a penetrating mode. According to the sintering device, the heat preservation heating box, the sintering box and the sealing cover are arranged, so that the problems that in the initial stage of sintering raw materials, the temperature of the sintering device can be increased too fast and exceeds the temperature range suitable for sintering, and gas in the sintering device or gas generated by sintering can react with the raw materials in the sintering process, and the sintering efficiency is low are solved. The sintered materials may adhere to the inner wall of the device, and cleaning and discharging are inconvenient.

Description

Technical Field

[0001] This utility model belongs to the field of lithium manganese iron phosphate technology, and in particular relates to a sintering apparatus for preparing lithium manganese iron phosphate by solid-state method. Background Technology

[0002] Lithium manganese iron phosphate (LFP) is a novel phosphate-based lithium-ion battery cathode material formed by doping lithium iron phosphate with a certain proportion of manganese. The doping of manganese effectively combines the advantages of both iron and manganese. Furthermore, manganese and iron are both located in the fourth period of the periodic table and are adjacent to each other, possessing similar ionic radii and some chemical properties; therefore, doping does not significantly affect the original structure. The preparation methods of LFP can be divided into two main categories: solid-state and liquid-state methods. The solid-state method has advantages such as simple and mature processes, low preparation costs, and ease of large-scale industrialization. However, the solid-state process requires sintering the LFP. Sintering refers to transforming powdered materials into a dense body. After molding, the dense body obtained through sintering is a polycrystalline material, whose microstructure consists of crystals, glass, and pores. The sintering process directly affects the grain size, pore size, and grain boundary shape and distribution in the microstructure, thus affecting the material's performance. However, it still has the following drawbacks in practical applications:

[0003] Utility model CN217785672U discloses a drying and sintering device for producing iron phosphate. The sintering device body has a heating box mounted on its surface, a feed inlet at its top, a control console mounted on its surface, a discharge port at its bottom, a fixed frame mounted on its body, and a main shaft movably inserted inside the sintering device body. A heating cylinder is mounted on the main shaft, and a feeding port is mounted on the heating cylinder. During the sintering process, the material may adhere to the inner wall of the sintering device, requiring timely cleaning to avoid affecting heating efficiency. However, cleaning is time-consuming and labor-intensive, reducing processing efficiency.

[0004] When sintering lithium manganese iron phosphate, it is often necessary to keep the raw materials within a suitable temperature range. However, in actual operation, many sintering devices that use fuel combustion for heating may heat up too quickly during the heating process, which may affect the quality of lithium manganese iron phosphate. In addition, the gas inside the device may react with the raw materials during the heating process, reducing the quality of lithium manganese iron phosphate. Utility Model Content

[0005] The purpose of this invention is to provide a sintering apparatus for preparing lithium manganese iron phosphate by solid-state method. By using a heat preservation heating box, a sintering box and a sealing cover, the invention solves the problems that the temperature of the sintering apparatus may rise too quickly in the early stage of sintering the raw materials and exceed the appropriate sintering temperature range. In addition, the gas in the apparatus or the gas generated during sintering may react with the raw materials, and the sintered material may adhere to the inner wall of the apparatus, making it inconvenient to clean and discharge.

[0006] To solve the above-mentioned technical problems, this utility model is achieved through the following technical solution:

[0007] This utility model relates to a sintering apparatus for preparing lithium manganese iron phosphate by solid-state method, comprising a heat preservation heating box, a sintering box, and a sealing cover. Multiple pusher cylinders are snapped onto one end of the heat preservation heating box, and the sintering box is snapped onto the top end of the heat preservation heating box. Multiple ventilation and heat-conducting baffles are welded and fixed inside the sintering box. A discharge guide cover is rotatably snapped onto one end of the sintering box, and a sealing cover is snapped and fixed onto the top of the sintering box. A filter assembly is provided on the top of the sealing cover, and an air pump is snapped onto the top of the filter assembly.

[0008] The insulated chamber prevents significant heat loss, and the heating structure within it heats the sintering chamber, sintering the raw materials. After sintering, a pusher cylinder moves the material within the sintering chamber, discharging it and scraping off material adhering to the inner wall and the surface of the ventilation and heat-conducting baffles, reducing cleaning difficulty within the sintering unit. During heating, multiple ventilation and heat-conducting baffles increase the contact area between the raw materials and the sintering chamber, allowing for rapid and uniform heating. During the heating process, air is drawn from the sintering chamber by an air pump and filtered through a filter assembly. The high-temperature gas is then returned to the sintering chamber through a ventilation and heat-conducting baffle, preventing reactions between the gas components and the raw materials and ensuring sintering efficiency. When the temperature inside the sintering chamber exceeds a threshold, cold water is pumped into the condenser tubes to cool the gas passing through the ventilation and heat-conducting baffles, further cooling the sintering chamber and ensuring that the temperature inside the sintering chamber remains within a suitable range. The water after heat exchange through the condenser tubes can also collect heat, preventing heat waste.

[0009] Furthermore, each of the pushing cylinders is slidably connected to a telescopic tube at one end, and a pushing plate is connected to the other end of the telescopic tube. The telescopic tube is inserted through and connected to one end of the heat preservation and heating box.

[0010] The pusher cylinder can drive the pusher plate to move, which in turn drives the material in the sintering box to discharge the material. It can also scrape off the material adhering to the inner wall of the sintering box and the surface of the ventilation and heat conduction baffle, ensuring discharge efficiency and reducing cleaning difficulty.

[0011] Furthermore, a rotating motor is snapped onto one end of the discharge guide cover, and the other end of the rotating motor is snapped onto and fixed to one end of the heat preservation heating box. The sintering box has multiple inlets at the other end of the discharge guide cover, and the multiple inlets and multiple ventilation and heat conduction baffles are alternately arranged. The multiple pusher plates are respectively inserted through the multiple inlets.

[0012] When material needs to be discharged, the motor can be turned to open the discharge guide cover. The material is pushed onto the surface of the discharge guide cover by the pusher plate and discharged along the discharge guide cover under the action of gravity. The operation is simple and convenient.

[0013] Furthermore, each of the ventilation and heat-conducting baffles has an air inlet at one end of its top, a ventilation pipe is welded through the bottom of one end of each of the ventilation and heat-conducting baffles, an exhaust pipe is welded through the top of the ventilation pipe, multiple ventilation pipes are inserted through the bottom of one end of the sintering box, multiple exhaust pipes are inserted through the top of one end of the sintering box, and multiple exhaust pipes are respectively located at the top of multiple inlets.

[0014] Multiple ventilation and heat-conducting baffles can increase the contact area between the material and the sintering box, enabling the material to heat up quickly and evenly, thus ensuring the quality of the material.

[0015] Furthermore, the top end of the sealing cover has multiple connection ports, and a ventilation frame is welded and fixed to the top end of the sealing cover. The multiple connection ports are connected to the ventilation frame, and the multiple connection ports are respectively attached to the top of multiple air inlets. A feed pipe is welded through the top of the sealing cover relative to the other end of the ventilation frame. The top of the feed pipe is rotatably snapped with a feed cover, and the feed pipe is connected to the sintering box.

[0016] During the heating process, air is drawn from the sintering chamber by an air pump, allowing the gas to be filtered in the filter assembly. The gas is then returned to the sintering chamber through the ventilation and heat-conducting baffle, preventing the components in the gas from reacting with the raw materials and ensuring sintering efficiency.

[0017] Furthermore, one end of the filter assembly is inserted and snapped into one side of the feed pipe, one end of the air pump is inserted and snapped into a return pipe, the other end of the return pipe is inserted and snapped into the top of the ventilation frame, and a condenser pipe is snapped and fixed to the outer circumference of the return pipe.

[0018] When the temperature inside the sintering chamber exceeds the threshold, cold water is pumped into the condenser tube to cool the gas passing through the return tube, further cooling the ventilation heat-conducting baffle and the inside of the sintering chamber, ensuring that the temperature inside the sintering chamber is always within a suitable range, and the water after heat exchange through the condenser tube can collect heat to avoid heat waste.

[0019] This utility model has the following beneficial effects:

[0020] This invention solves the problem of materials adhering to the inner wall of the sintering device during the sintering process by setting up an insulated heating box and a sintering box. This requires timely cleaning to avoid affecting heating efficiency, but cleaning is time-consuming and labor-intensive, reducing processing efficiency. When discharging, the discharge guide cover is rotated to open, and the pusher cylinder is controlled to drive the pusher plate to move. While discharging lithium manganese iron phosphate in the sintering box, the lithium manganese iron phosphate adhering to the sintering box can be scraped off, reducing the difficulty of cleaning inside the sintering device and greatly improving the convenience of using the device.

[0021] This invention solves the problem that during the sintering process of lithium manganese iron phosphate, the raw materials often need to be kept within a suitable temperature range. However, in actual operation, many sintering devices that use fuel combustion for heating may heat up too quickly, affecting the quality of lithium manganese iron phosphate. Furthermore, the gas inside the device may react with the raw materials during the heating process, reducing the quality of lithium manganese iron phosphate. During the sintering process, an air pump evacuates the sintering chamber, allowing the gas to be filtered through a filter assembly to prevent reactions between the gas components and the raw materials. When the temperature inside the sintering chamber exceeds a threshold, cold water is pumped into the condenser to cool the gas passing through the return pipe, further cooling the sintering chamber and ensuring that the temperature inside the sintering chamber remains within a suitable range, thus guaranteeing the quality of lithium manganese iron phosphate. Attached Figure Description

[0022] Figure 1 This is a structural rendering of the present invention;

[0023] Figure 2 This is a drawing of the heat preservation and heating box of this utility model;

[0024] Figure 3 This is a structural diagram of the sintering box of this utility model;

[0025] Figure 4 This is a side view of the sintering box of this utility model;

[0026] Figure 5 This is a structural diagram of the sealing cap of this utility model;

[0027] Figure 6 This is a bottom view of the sealing cap of this utility model.

[0028] Figure label:

[0029] 1. Insulated heating box; 101. Pushing cylinder; 102. Telescopic tube; 103. Pushing plate; 2. Sintering box; 201. Ventilation and heat conduction partition; 202. Discharge guide cover; 203. Rotary motor; 204. Air inlet; 205. Ventilation pipe; 206. Inlet; 207. Exhaust pipe; 3. Sealing cover; 301. Filter assembly; 302. Air pump; 303. Condenser pipe; 304. Feed pipe; 305. Return pipe; 306. Ventilation frame; 307. Feed cover; 308. Connection port. Detailed Implementation

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention.

[0031] Please see Figure 1-6 As shown, this utility model is a sintering device for preparing lithium manganese iron phosphate by solid-state method, including a heat preservation heating box 1, a sintering box 2 and a sealing cover 3. Multiple pusher cylinders 101 are snapped to one end of the heat preservation heating box 1. The sintering box 2 is snapped through to one end of the top of the heat preservation heating box 1. Multiple ventilation and heat conduction baffles 201 are welded and fixed inside the sintering box 2. A discharge guide cover 202 is rotatably snapped to one end of the sintering box 2. The sealing cover 3 is snapped and fixed to the top of the sintering box 2. A filter assembly 301 is provided on the top of the sealing cover 3. An air pump 302 is snapped through to the top of the filter assembly 301.

[0032] Open the feed pipe 304 and pour the raw material into the sintering chamber 2. Close the feed pipe 304 and control the air pump 302 to evacuate the sintering chamber 2, so that the gas enters the filter assembly 301 for filtration and then flows back into the sintering chamber 2. This prevents the components in the gas from reacting with the raw material at high temperatures. Control the heat preservation heating box 1 to heat the surface of the sintering chamber 2, and transfer the heat to the raw material through the sintering chamber 2 and the ventilation and heat conduction baffle 201 to sinter the raw material. When the temperature in the sintering chamber 2 reaches the threshold, pump cold water into the condenser pipe 303 to exchange heat with the gas passing through the return pipe 305, so that the gas entering the ventilation and heat conduction baffle 201 can be sintered. The low-temperature air in the partition 201 and sintering box 2 can cool the sintering box 2 and the raw materials, keeping the raw materials at a suitable sintering temperature. After the lithium manganese iron phosphate is sintered, the control motor 203 drives the discharge guide cover 202 to rotate and open, and controls the pusher cylinder 101 to drive the pusher plate 103 to move, so that the material in the sintering box 2 can move under the action of the pusher. At the same time, the lithium manganese iron phosphate attached to the sintering box 2 and the surface of the ventilation and heat conduction partition 201 is scraped off, so that the lithium manganese iron phosphate is discharged along the discharge guide cover 202 under the action of gravity. After the discharge is completed, only the surface of the pusher plate 103 needs to be cleaned.

[0033] Among them, such as Figure 1-4As shown, each pusher cylinder 101 has a telescopic tube 102 slidably connected to one end, and a pusher plate 103 connected to the other end of the telescopic tube 102. The telescopic tube 102 is inserted through and connected to one end of the heat preservation and heating box 1. A rotary motor 203 is connected to one end of the discharge guide cover 202, and the other end of the rotary motor 203 is fixed to one end of the heat preservation and heating box 1. The sintering box 2 has multiple inlets 206 at the other end of the discharge guide cover 202. The multiple inlets 206 and multiple ventilation and heat conduction baffles 201 are alternately arranged. Multiple pusher plates 103 are inserted into multiple sockets 206 respectively. Each ventilation and heat conduction baffle 201 has an air inlet 204 at one end of its top. A ventilation pipe 205 is welded through the bottom of one end of each ventilation and heat conduction baffle 201. An exhaust pipe 207 is welded through the top of the ventilation pipe 205. Multiple ventilation pipes 205 are inserted through the bottom of one end of the sintering box 2. Multiple exhaust pipes 207 are inserted through the top of one end of the sintering box 2. Multiple exhaust pipes 207 are located at the top of multiple sockets 206 respectively.

[0034] During the sintering of lithium manganese iron phosphate, the raw material is poured into the sintering box 2 and the amount of raw material is lower than the top of the pusher plate 103. The sintering box 2 is heated by the heat preservation heating box 1 to further heat the raw material. After the lithium manganese iron phosphate is sintered, the rotating motor 203 is controlled to drive the discharge guide cover 202 to rotate downward and open. The pusher cylinder 101 is controlled to drive the extension tube 102 to stretch, which further drives the pusher plate 103 to move. The material in the sintering box 2 moves under the action of the pushing force. At the same time, the lithium manganese iron phosphate attached to the surface of the ventilation and heat conduction partition 201 in the sintering box 2 is scraped off. The lithium manganese iron phosphate is discharged along the discharge guide cover 202 under the action of gravity. After the discharge is completed, only the surface of the pusher plate 103 needs to be cleaned.

[0035] Among them, such as Figure 1 , 5 As shown in Figure 6, a plurality of connection ports 308 are provided through one end of the top of the sealing cover 3. A ventilation frame 306 is welded and fixed to one end of the top of the sealing cover 3. The plurality of connection ports 308 and the ventilation frame 306 are connected through the sealing cover 3. The plurality of connection ports 308 are respectively attached to the top of the plurality of air inlets 204. A feed pipe 304 is welded through the other end of the top of the sealing cover 3 relative to the ventilation frame 306. A feed cover 307 is rotatably snapped onto the top of the feed pipe 304. The feed pipe 304 is connected through the sintering box 2. One end of the filter assembly 301 is snapped through and snapped onto one side of the feed pipe 304. One end of the air pump 302 is snapped through and snapped onto the return pipe 305. The other end of the return pipe 305 is snapped through and snapped onto the top of the ventilation frame 306. A condenser pipe 303 is snapped and fixed onto the outer circumference of the return pipe 305.

[0036] During feeding, the feed cover 307 is rotated open, and the raw material is poured into the sintering chamber 2 through the feed pipe 304. The feed cover 307 is then closed, and the air pump 302 is controlled to evacuate the sintering chamber 2, allowing the gas to enter the filter assembly 301 for filtration. The gas then enters the ventilation and heat-conducting baffle 201 through the return pipe 305 and the ventilation rack 306, and then flows back into the sintering chamber 2 through the ventilation pipe 205 and the exhaust pipe 207. This prevents the components in the gas from reacting with the raw material at high temperatures. During the heating process, the gas is further filtered to prevent the heated gas from reacting with the raw material. When the temperature in the sintering chamber 2 reaches the threshold, cold water is pumped into the condenser pipe 303 to further exchange heat with the gas passing through the return pipe 305. This allows the low-temperature gas entering the ventilation and heat-conducting baffle 201 and the sintering chamber 2 to cool the sintering chamber 2 and the raw material, ensuring that the raw material is always at a suitable sintering temperature.

[0037] The specific working principle of this utility model is as follows: During the sintering of lithium manganese iron phosphate, the feed cover 307 is rotated and opened, and the raw material is poured into the sintering chamber 2 through the feed pipe 304. The amount of raw material is controlled to be lower than the top of the pusher plate 103. The feed cover 307 is closed, and the air pump 302 is controlled to evacuate the sintering chamber 2, so that the gas enters the filter assembly 301 for filtration, and enters the ventilation and heat conduction partition 201 through the return pipe 305 and the ventilation rack 306. Then, the gas is returned to the sintering chamber 2 through the ventilation pipe 205 and the exhaust pipe 207 to avoid the components in the gas from reacting with the raw material at high temperature. The sintering chamber 2 is heated by the heat preservation heating box 1 to further heat the raw material. When the temperature in the sintering chamber 2 reaches the threshold, the pump in the condenser pipe 303 is activated. Cold water is introduced to further exchange heat with the gas passing through the return pipe 305, so that the low-temperature gas entering the ventilation and heat-conducting baffle 201 and the sintering box 2 cools down the sintering box 2 and the raw materials, keeping the raw materials at a suitable sintering temperature. After the lithium manganese iron phosphate is sintered, the control motor 203 drives the discharge guide cover 202 to rotate downward and open, and the control cylinder 101 drives the extension tube 102 to stretch, further driving the pusher plate 103 to move, so that the material in the sintering box 2 moves under the action of the pusher, and at the same time scrapes off the lithium manganese iron phosphate adhering to the surface of the ventilation and heat-conducting baffle 201 in the sintering box 2, so that the lithium manganese iron phosphate is discharged along the discharge guide cover 202 under the action of gravity. After the discharge is completed, only the surface of the pusher plate 103 needs to be cleaned.

[0038] The above are merely preferred embodiments of the present utility model and do not limit the present utility model. Any modifications, equivalent substitutions, or improvements made to the technical solutions described in the foregoing embodiments, or to some of the technical features, shall fall within the protection scope of the present utility model.

Claims

1. A sintering apparatus for preparing lithium manganese iron phosphate by solid-state method, comprising a heat-insulating heating box (1), a sintering box (2), and a sealing cover (3), characterized in that: The heat preservation heating box (1) is connected to a plurality of pusher cylinders (101) at one end. The heat preservation heating box (1) is connected to a sintering box (2) through one end. The sintering box (2) is welded and fixed with a plurality of ventilation and heat conduction baffles (201). The sintering box (2) is connected to a discharge guide cover (202) through one end. The sintering box (2) is connected to a sealing cover (3) through the top. The sealing cover (3) is provided with a filter assembly (301) at the top. The filter assembly (301) is connected to an air pump (302) through the top.

2. The sintering apparatus for solid-state preparation of lithium manganese iron phosphate according to claim 1, characterized in that: Each of the pusher cylinders (101) has a telescopic tube (102) slidably connected to one end, and a pusher plate (103) is connected to the other end of the telescopic tube (102). The telescopic tube (102) is inserted through and connected to one end of the heat preservation heating box (1).

3. The sintering apparatus for solid-state preparation of lithium manganese iron phosphate according to claim 2, characterized in that: One end of the discharge guide cover (202) is connected to a rotating motor (203), and the other end of the rotating motor (203) is connected to one end of the heat preservation heating box (1). The sintering box (2) has multiple inlets (206) at the other end relative to the discharge guide cover (202). The multiple inlets (206) and multiple ventilation and heat conduction baffles (201) are alternately arranged, and multiple pusher plates (103) are respectively inserted into the multiple inlets (206).

4. The sintering apparatus for solid-state preparation of lithium manganese iron phosphate according to claim 3, characterized in that: Each of the ventilation and heat-conducting baffles (201) has an air inlet (204) at one end of its top. A ventilation pipe (205) is welded through the bottom of one end of each of the ventilation and heat-conducting baffles (201). An exhaust pipe (207) is welded through the top of the ventilation pipe (205). Multiple ventilation pipes (205) are inserted through the bottom of one end of the sintering box (2). Multiple exhaust pipes (207) are inserted through the top of one end of the sintering box (2). Multiple exhaust pipes (207) are located at the top of multiple inlets (206).

5. The sintering apparatus for solid-state preparation of lithium manganese iron phosphate according to claim 4, characterized in that: The top end of the sealing cover (3) is provided with multiple connection ports (308). A ventilation frame (306) is welded and fixed to the top end of the sealing cover (3). The multiple connection ports (308) and the ventilation frame (306) are connected through each other. The multiple connection ports (308) are respectively attached to the top of multiple air inlets (204). The top end of the sealing cover (3) relative to the ventilation frame (306) is welded through with a feed pipe (304). The top of the feed pipe (304) is rotatably snapped with a feed cover (307). The feed pipe (304) and the sintering box (2) are connected through each other.

6. The sintering apparatus for solid-state preparation of lithium manganese iron phosphate according to claim 5, characterized in that: One end of the filter assembly (301) is inserted and snapped into one side of the feed pipe (304), one end of the air pump (302) is inserted and snapped into the return pipe (305), the other end of the return pipe (305) is inserted and snapped into the top of the ventilation frame (306), and the outer circumference of the return pipe (305) is snapped and fixed with the condenser pipe (303).

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