Graphite battery negative electrode material testing and sampling equipment

Abstract

The invention discloses graphite battery negative electrode material testing and sampling equipment, and particularly relates to the technical field of battery negative electrode material reaction treatment, the graphite battery negative electrode material testing and sampling equipment comprises a base, a crushing and shunting assembly is arranged on the base, and the crushing and shunting assembly comprises a reaction kettle body arranged at the top of the base. Through a stepped crushing structure of the spiral crushing belt and the twisting ring, and a centrifugal force field eddy current effect formed by rotation of the inclined grinding block, three-stage treatment of materials is realized. Wherein the spiral lead angle design of the spiral crushing belt can ensure that blocky materials are uniformly stressed in the axial direction, and local over-crushing is avoided; the gap between the twisting ring and the base plate is adjustable and can adapt to test scenes with different particle size requirements; the powder can be automatically graded according to the particle size through the eddy current effect generated by rotation of the inclined grinding block, qualified particles are accurately filtered and deposited through the filter screen cover, coarse particles flow back to the crushing cavity through the guide cylinder to be continuously treated, and the problem that particles are not evenly distributed in an existing quartering method sampling process is effectively solved.

Description

Technical Field

[0001] This invention relates to the field of reaction processing technology for battery anode materials, and more specifically, to a testing and sampling device for graphite battery anode materials. Background Technology

[0002] In the field of lithium-ion battery performance testing technology, the accuracy of performance evaluation results (such as specific capacity, cycle life, conductivity, crystal structure integrity, etc.) of graphite battery anode materials directly depends on the quality of samples that are statistically representative and meet the testing standards. Currently, industrially produced graphite anode materials (including bulk compacts, powder agglomerates, etc.) exhibit inherent microscopic inhomogeneity. This characteristic is a core technical bottleneck leading to deviations in test results, specifically manifested in the following two aspects:

[0003] From the perspective of particle morphology, mainstream anode materials such as artificial graphite mostly exist in the form of "secondary particles," which are formed by the aggregation of multiple "primary particles." The aggregation density and particle size distribution of secondary particles vary significantly between different production batches, and even between different regions within the same batch. Some natural graphite materials also have the problem of uneven thickness of the stacked flake particles. If random sampling is taken directly from the surface of the material stack or a local area (such as scraping surface powder or cutting off the edge of a block), the particle size distribution of the obtained sample cannot reflect the true distribution of the overall material. As a result, the results of subsequent specific surface area tests, charge-discharge cycle tests, etc., only represent "local characteristics," and the deviation from the actual performance of the batch material can reach 15%-30%.

[0004] From the perspective of compositional distribution, to improve the cycle stability of anode materials, surface coating (such as carbon coating, oxide coating) or elemental doping (such as nitrogen, boron doping) processes are commonly used in industry. However, due to limitations such as airflow distribution in coating equipment and dopant diffusion rate, the coating layer thickness on the material surface is prone to gradient differences of "thin at the edges and thick at the center," and the distribution of dopants within the particles also exhibits local enrichment or absence. Existing sampling methods do not specifically address this type of compositional unevenness, directly leading to extreme cases such as "coating failure samples" and "highly doped samples" being misjudged as part of the batch material performance during testing, seriously affecting the reliability of battery design and selection.

[0005] While the industry currently employs the conventional method of "quartering sampling + ball milling homogenization," it suffers from two major technical drawbacks: First, the quartering method relies on manual operation, and material spillage and particle stratification during sampling can lead to insufficient representativeness. Second, ball milling can only achieve a rough uniformity in particle size, failing to address the uneven microscopic distribution of coating layers and dopants. Furthermore, ball milling may introduce mechanical impurities (such as grinding ball debris), interfering with subsequent purity testing. In addition, key performance parameters of graphite materials, such as the degree of graphitization and lattice defects, require pretreatment under specific temperature conditions for accurate detection. However, existing sampling equipment lacks an integrated "pretreatment-sampling-homogenization" function, making samples susceptible to moisture and oxidation during transfer, further affecting testing accuracy. Therefore, this paper proposes an integrated sampling and testing device for graphite battery anode materials that integrates "efficient crushing, precise grading, gradient preheating, and interference-free sampling" to address the technical problems of insufficient sample representativeness, low pretreatment efficiency, and numerous interfering factors in existing technologies. Summary of the Invention

[0006] In order to overcome the above-mentioned defects of the prior art, the present invention provides a testing and sampling device for graphite battery anode materials, which aims to solve the problems mentioned in the background art.

[0007] This invention provides the following technical solution: a graphite battery negative electrode material testing and sampling device, including a base, on which a crushing and diversion component is provided;

[0008] The pulverizing and diverting assembly includes a reaction vessel body disposed on the top of the base. A filter screen cover is disposed in the middle of the reaction vessel body. A first limiting ring is rotatably connected to the outer side of the filter screen cover. A second limiting ring is sleeved on the outer side of the first limiting ring. Several inclined grinding blocks are distributed between the first limiting ring and the second limiting ring.

[0009] The bottom of the second limiting ring is bolted with a toothed ring. Several extension cylinders are fixedly installed on the reactor body, and a guide cylinder is embedded in each of the extension cylinders. A spring is provided in the middle of each of the multiple guide cylinders, and a striking ball is fixedly installed at the bottom of each spring. The striking ball abuts against the inclined grinding block. A tight band is provided at the top of the inner cavity of the extension cylinder. An inner liner is provided on the inner wall of the tight band. Several connecting blocks are bolted to the inner liner. The multiple connecting blocks extend to the guide cylinder and are engaged with the guide cylinder. The bottom end of the guide cylinder extends to the top of the inclined grinding block, and an arc groove is opened on the side of the guide cylinder facing the second limiting ring.

[0010] Optionally, in a possible implementation, a crushing cylinder is provided at the top of the reactor body, and a pad is fixedly provided at the bottom of the crushing cylinder. The pad is bolted to the top of the reactor body, and a rotating shaft is rotatably connected to the top of the pad. A horizontal plate is fixedly provided on the rotating shaft. The horizontal plate is located at the top of the inner cavity of the crushing cylinder and is rotatably connected to the crushing cylinder. The pad has several through holes located at the top of corresponding extension cylinders. Several crushing belts are sleeved on the outside of the rotating shaft, and the top end of each crushing belt is fixed to the horizontal plate. The crushing belts are spiral in shape, and the bottom ends of multiple crushing belts are fixedly provided with... A rudder ring is provided, located on top of a pad. A conical sleeve is bolted to the inner wall of the crushing cylinder, covering the outside of the crushing zone. A first electric heating rod is embedded in the conical sleeve. A first motor for driving the rotating shaft is bolted to the top of the crushing cylinder. A gear is provided on the outside of the gear ring, meshing with the gear ring. A second motor for driving the gear is bolted to the bottom of the base. Several second electric heating rods are embedded on the outside of the reaction vessel body, and each second electric heating rod penetrates the filter screen and extends to the middle of the filter screen. The reaction vessel body is mounted on the base by a bracket.

[0011] The technical effects and advantages of this invention are as follows:

[0012] 1. This invention achieves three-stage material processing through a stepped crushing structure of a spiral crushing belt and a grinding ring, combined with the centrifugal force field vortex effect generated by the rotation of the inclined grinding block. Specifically, the spiral angle design of the spiral crushing belt ensures uniform axial force on lumpy materials, avoiding localized over-crushing; the adjustable gap between the grinding ring and the pad allows for adaptation to testing scenarios with different particle size requirements; the vortex effect generated by the rotation of the inclined grinding block enables automatic particle size classification of powders. Qualified particles are precisely filtered and deposited through a filter screen, while coarse particles are returned to the crushing chamber for further processing via a guide tube, effectively solving the problem of uneven particle distribution in existing quartering sampling methods.

[0013] 2. The dual heating system of the first electric heating rod in the conical sleeve and the second electric heating rod in the reaction vessel body of this invention forms a progressive heat treatment process suitable for graphite material performance testing. Specifically, the first electric heating rod in the conical sleeve preheats the material, removing adsorbed moisture and volatile impurities from the sample surface, thus preventing abnormal capacity decay during the initial charge-discharge test in subsequent electrochemical performance testing. The second electric heating rod in the reaction vessel body extends through the filter screen to the middle, enabling lattice adjustment pretreatment of the deposited sample, making the graphitization degree test results closer to the true state of the material. It also adapts to different testing standards, avoiding sample transfer losses and contamination problems caused by the separate preheating treatment required in existing equipment.

[0014] 3. The equipment of this invention adopts multiple anti-interference measures in its structural design: First, the arc groove opened on the side of the guide cylinder facing the second limiting ring can guide the airflow to flow in a fixed direction, avoiding cross-contamination caused by powder adhering to the inner wall of the guide cylinder; Second, the synergistic effect of the striking ball and the spring can periodically strike the inclined grinding block during its rotation, which can not only prevent the material from agglomerating on the surface of the inclined grinding block, but also transmit the vibration to the filter screen cover, avoiding particle retention deviation caused by filter screen blockage; thus meeting the requirements of subsequent testing.

[0015] 4. This invention integrates crushing, grading, preheating, and sampling functions into the same reaction system, eliminating the need for manual material transfer and effectively shortening the sample preparation cycle. Compared to traditional four-part sampling methods, it reduces time, minimizes errors caused by manual intervention, and further ensures the stability of the testing process. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this disclosure, the accompanying drawings used in some embodiments will be briefly described below. Obviously, the drawings described below are only drawings of some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams and are not intended to limit the actual size of the product, the actual flow of the method, the actual timing of the signals, etc. involved in the embodiments of this disclosure.

[0017] Figure 1 This is a front view of the overall structure of the present invention.

[0018] Figure 2 This is a side view of the overall structure of the present invention.

[0019] Figure 3 This is a schematic diagram showing the reactor body, second electric heating rod, base, pad, and spring assembled together according to the present invention.

[0020] Figure 4 This is a schematic diagram of the rotating shaft, horizontal plate, crushing belt, and crushing ring of the present invention.

[0021] Figure 5 This is a schematic diagram of the reaction vessel body, gears, springs, and extension cylinder of the present invention.

[0022] Figure 6 This is a schematic diagram of the filter screen, first limiting ring, second limiting ring, inclined grinding block, guide cylinder and toothed ring of the present invention.

[0023] Figure 7 This is a perspective view of the flow guide tube, clamp, striking ball, and spring of the present invention.

[0024] Figure 8 This is a perspective view of the filter screen, first limiting ring, second limiting ring, inclined grinding block, and toothed ring of the present invention.

[0025] The attached figures are labeled as follows: 1. Base; 2. Reactor body; 3. Filter screen cover; 4. First limiting ring; 5. Second limiting ring; 6. Inclined grinding block; 7. Gear ring; 8. Flow guide tube; 9. Spring; 10. Striking ball; 11. Hoop; 12. Inner liner ring; 13. Connecting block; 14. Arc groove; 15. Crushing cylinder; 16. Pad plate; 17. Rotating shaft; 18. Horizontal plate; 19. Crushing belt; 20. Grinding ring; 21. Conical sleeve; 22. First electric heating rod; 23. First motor; 24. Gear; 25. Second motor; 26. Second electric heating rod; 27. Extension cylinder. Detailed Implementation

[0026] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] As attached Figure 1 -Appendix Figure 8 The graphite battery negative electrode material testing and sampling equipment shown includes a crushing and diversion component comprising a reaction vessel body 2 set on the top of the base 1, a filter screen cover 3 set in the middle of the reaction vessel body 2, a first limiting ring 4 rotatably connected to the outer side of the filter screen cover 3, a second limiting ring 5 sleeved on the outer side of the first limiting ring 4, and a number of inclined grinding blocks 6 distributed between the first limiting ring 4 and the second limiting ring 5.

[0028] The bottom of the second limiting ring 5 is bolted with a toothed ring 7. Several extension cylinders 27 are fixedly installed on the reactor body 2, and each extension cylinder 27 is embedded with a guide cylinder 8. A spring 9 is installed in the middle of each guide cylinder 8, and a striking ball 10 is fixedly installed at the bottom of each spring 9. The striking ball 10 abuts against the inclined grinding block 6. A tight band 11 is installed at the top of the inner cavity of the extension cylinder 27. An inner liner ring 12 is installed on the inner wall of the tight band 11. Several connecting blocks 13 are bolted to the inner liner ring 12. The connecting blocks 13 extend to the guide cylinder 8 and are engaged with the guide cylinder 8. The bottom end of the guide cylinder 8 extends to the top of the inclined grinding block 6, and an arc groove 14 is opened on the side of the guide cylinder 8 facing the second limiting ring 5.

[0029] A crushing cylinder 15 is installed at the top of the reactor body 2. A pad 16 is fixedly installed at the bottom of the crushing cylinder 15. The pad 16 is bolted to the top of the reactor body 2. A rotating shaft 17 is rotatably connected to the top of the pad 16. A horizontal plate 18 is fixedly installed on the rotating shaft 17. The horizontal plate 18 is located at the top of the inner cavity of the crushing cylinder 15 and is rotatably connected to the crushing cylinder 15. Several through holes are opened on the pad 16, which are respectively located at the top of the corresponding extension cylinder 27. Several crushing belts 19 are sleeved on the outside of the rotating shaft 17, and the top end of each crushing belt 19 is fixed on the horizontal plate 18. The crushing belts 19 are spiral in shape. A grating ring 20 is fixedly installed at the bottom end of each crushing belt 19. 20 is located on top of the pad 16. A conical sleeve 21 is bolted to the inner wall of the crushing cylinder 15. The conical sleeve 21 covers the outside of the crushing belt 19. A first electric heating rod 22 is embedded in the conical sleeve 21. A first motor 23 for driving the rotating shaft 17 to rotate is bolted to the top of the crushing cylinder 15. A gear 24 is provided on the outside of the gear ring 7. The gear 24 meshes with the gear ring 7. A second motor 25 for driving the gear 24 to rotate is bolted to the bottom of the base 1. Several second electric heating rods 26 are embedded on the outside of the reaction vessel body 2. Each second electric heating rod 26 penetrates the filter screen 3 and extends to the middle of the filter screen 3. The reaction vessel body 2 is mounted on the base 1 by a bracket.

[0030] The specific working principle is as follows: the raw material is added into the crushing cylinder 15, and the raw material is gathered and guided by the cone sleeve 21. The first motor 23 drives the rotating shaft 17 to rotate. When the rotating shaft 17 rotates, it drives the crushing belt 19, the horizontal plate 18 and the grinding ring 20 to rotate. When the crushing belt 19 rotates, it crushes the larger pieces of material, while the grinding ring 20 grinds the material crushed by the crushing belt 19. It is easy to divert the crushed raw material through the through holes on each pad 16. When the raw material is crushed in the middle of the cone sleeve 21, the first electric heating rod 22 realizes the function of wrapping and heating the raw material, realizing the function of heat treatment of the material on the basis of crushing.

[0031] After the raw material is diverted through the through-hole, it is conveyed through the guide tube 8 to the space between the filter screen 3 and the reactor body 2, allowing the raw material particles to be conveyed between the first limiting ring 4 and the second limiting ring 5. Simultaneously, the raw material particles are diverted by the various inclined grinding blocks 6 between the first limiting ring 4 and the second limiting ring 5. The second motor 25 drives the gear 24 to rotate, which in turn drives the gear ring 7 to rotate, causing the first limiting ring 4, the second limiting ring 5, and the inclined grinding blocks 6 to rotate. The rotation of the inclined grinding blocks 6 allows for the grinding of the material between the first limiting ring 4 and the second limiting ring 5. The crushing process allows granular materials to be pulverized. Simultaneously, the rotation of the inclined grinding block 6, the first limiting ring 4, and the second limiting ring 5 generates airflow, which extracts the pulverized material. The pulverized material is then filtered through the filter screen 3 and deposited inside the filter screen 3. It is then heated by the second electric heating rod 26, thereby increasing the specific surface area. The powder particles are smaller and the specific surface area is larger, making heat treatment (such as graphitization, coating, doping, etc.) more complete and the reaction more thorough. Powdered graphite is more likely to achieve lattice rearrangement at high temperatures, improving the graphitization rate and enhancing conductivity and cycle stability.

[0032] Furthermore, when the first limiting ring 4, the second limiting ring 5, and the inclined grinding block 6 rotate, the striking ball 10 can come into contact with the inclined grinding block 6. When the striking ball 10 comes into contact with the inclined grinding block 6, it moves upward and compresses the spring 9. The spring 9's own elasticity drives the striking ball 10 to reset, causing the striking ball 10 to strike the inclined grinding block 6. This facilitates the transmission of vibrations received by the first limiting ring 4, the second limiting ring 5, and the inclined grinding block 6 to the filter screen 3, preventing material deposited on the outside of the filter screen 3 from clogging the filter screen 3.

[0033] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A sampling and testing device for graphite battery negative electrode materials, comprising a base (1), characterized in that: The base (1) is provided with a crushing and diversion component; The pulverizing and diverting assembly includes a reactor body (2) disposed on the top of the base (1), a filter screen cover (3) disposed in the middle of the reactor body (2), a first limiting ring (4) rotatably connected to the outer side of the filter screen cover (3), a second limiting ring (5) sleeved on the outer side of the first limiting ring (4), and a plurality of inclined grinding blocks (6) distributed between the first limiting ring (4) and the second limiting ring (5). The bottom of the second limiting ring (5) is bolted with a toothed ring (7). Several extension cylinders (27) are fixedly arranged on the reactor body (2), and each extension cylinder (27) is embedded with a guide cylinder (8). A spring (9) is arranged in the middle of each of the multiple guide cylinders (8), and a striking ball (10) is fixedly arranged at the bottom end of each spring (9). The striking ball (10) abuts against the inclined grinding block (6).

2. The testing and sampling equipment for graphite battery negative electrode materials according to claim 1, characterized in that: The top of the inner cavity of the extension tube (27) is provided with a clamp (11), and an inner liner (12) is provided on the inner wall of the clamp (11). Several connecting blocks (13) are installed on the inner liner (12) by bolts.

3. The testing and sampling equipment for graphite battery negative electrode materials according to claim 2, characterized in that: Multiple connecting blocks (13) extend to the guide tube (8) and engage with the guide tube (8). The bottom end of the guide tube (8) extends above the inclined grinding block (6), and the guide tube (8) has an arc groove (14) on the side facing the second limiting ring (5).

4. The testing and sampling equipment for graphite battery negative electrode materials according to claim 1, characterized in that: The top of the reactor body (2) is provided with a crushing cylinder (15), and the bottom of the crushing cylinder (15) is fixedly provided with a pad (16), which is installed on the top of the reactor body (2) by bolts.

5. The testing and sampling device for graphite battery negative electrode materials according to claim 4, characterized in that: The top of the pad (16) is rotatably connected to a rotating shaft (17), and a horizontal plate (18) is fixedly installed on the rotating shaft (17). The horizontal plate (18) is located at the top of the inner cavity of the crushing cylinder (15) and is rotatably connected to the crushing cylinder (15). The pad (16) has several through holes located at the top of the corresponding extension cylinder (27).

6. The testing and sampling equipment for graphite battery negative electrode materials according to claim 5, characterized in that: The outer side of the rotating shaft (17) is fitted with several crushing belts (19), and the top of each crushing belt (19) is fixed on the horizontal plate (18). The crushing belt (19) is spiral in shape.

7. The testing and sampling device for graphite battery negative electrode materials according to claim 6, characterized in that: Each of the multiple crushing belts (19) is fixedly provided with a rubbing ring (20) at its bottom end, and the rubbing ring (20) is located on top of the pad (16).

8. The testing and sampling equipment for graphite battery negative electrode materials according to claim 6, characterized in that: The inner wall of the crushing cylinder (15) is fitted with a cone sleeve (21) by bolts. The cone sleeve (21) covers the outside of the crushing belt (19). A first electric heating rod (22) is embedded in the cone sleeve (21).

9. The testing and sampling equipment for graphite battery negative electrode materials according to claim 5, characterized in that: The top of the crushing cylinder (15) is bolted with a first motor (23) for driving the rotating shaft (17) to rotate. A gear (24) is provided on the outside of the gear ring (7), and the gear (24) meshes with the gear ring (7). The bottom of the base (1) is bolted with a second motor (25) for driving the gear (24) to rotate.

10. The testing and sampling device for graphite battery negative electrode materials according to claim 1, characterized in that: The outer side of the reactor body (2) is embedded with several second electric heating rods (26), and each second electric heating rod (26) penetrates the filter screen (3) and extends to the middle of the filter screen (3). The reactor body (2) is mounted on the base (1) by a bracket.

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