Jet mill for small-scale test of positive and negative electrode materials of lithium battery

Abstract

The utility model provides a jet mill for a lithium battery positive and negative electrode material small test, which comprises a crushing cylinder provided with a straight cylinder body and a conical cylinder body connected to the bottom of the straight cylinder body, a grading mechanism arranged in the straight cylinder body, a feeding hole formed in the middle of the straight cylinder body, and a crushing mechanism, the upper end part of the straight cylinder body is closed, and the conical cylinder body is in a head-removed conical shape with a large upper part and a small lower part. The crushing mechanism is a nozzle, the nozzle comprises a body inserted in a crushing cylinder and a spray head connected to the body and extending into the end part of the crushing cylinder, and the nozzle is divided into a first nozzle inserted in the lower end part of a straight cylinder and a second nozzle inserted in the bottom of a conical cylinder; the extension line of the axial lead of the first nozzle and the extension line of the axial lead of the second nozzle intersect at one point, so that component materials entering from the feeding hole can fall under the action of gravity, are guided to the second nozzle through the inner wall of the conical cylinder body, are blown upwards by the second nozzle, are crushed after passing through the intersection point, and are screened and discharged by the grading mechanism. The crushing rate is high, residues are few, and chippings cannot be mixed.

Description

Technical Field

[0001] The utility model relates to the technical field of air flow pulverizers, in particular to an air flow pulverizer for small-scale trial use of positive and negative electrode materials of lithium batteries. Background Art

[0002] Positive and negative electrode materials are the core of lithium batteries. Their components and ratios will seriously affect the charge and discharge multiples, cycle times, safety and other performance of lithium batteries. Before batch production of lithium batteries, the R&D department will conduct multiple small-scale tests on the positive and negative electrode materials to determine the most suitable components and ratios.

[0003] Since the positive and negative electrode materials in small-scale tests are mostly specific component materials and the amount used is small, the degree of crushing of the component materials by manufacturers is different, and the particle size after mixing is uneven, which will seriously affect the accuracy of the small-scale test results. To solve this problem, the R&D department usually uses contact crushing equipment such as small steel mills to crush the mixed positive and negative electrode materials. During the crushing process, the grinding head debris of the small steel mill is easily mixed into the positive and negative electrode materials, affecting the accuracy of the small-scale test results. Utility Model Content

[0004] The purpose of the utility model is to overcome one or more shortcomings in the prior art and to provide a small-scale airflow pulverizer for positive and negative electrode materials of lithium batteries.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is that the positive and negative electrode materials of lithium batteries are tested using an air flow mill, comprising:

[0006] A pulverizing cylinder extending in a vertical direction, comprising a straight cylinder and a conical cylinder connected to the bottom of the straight cylinder, wherein the upper end of the straight cylinder is closed and the conical cylinder is in the shape of a truncated cone with a larger upper portion and a smaller lower portion;

[0007] A grading mechanism, the grading mechanism is arranged in the straight cylinder, the grading mechanism includes a grading wheel rotatably arranged at the upper end of the straight cylinder and a discharger coaxially arranged with the grading wheel, the discharger is cylindrical and fixed to the straight cylinder;

[0008] A feed hole is provided in the middle of the straight cylinder, and is used to feed the component materials to be crushed into the crushing cylinder;

[0009] Crushing mechanism; the crushing mechanism is a nozzle, which includes a main body inserted on the crushing cylinder and a nozzle connected to the main body and extending into the inner end of the crushing cylinder. The nozzle is divided into a first nozzle inserted at the lower end of the straight cylinder and a second nozzle inserted at the bottom of the conical cylinder. The extension line of the axis of the first nozzle and the extension line of the axis of the second nozzle intersect at one point.

[0010] Preferably, a nut is threadedly connected to the body and is used to lock the body onto the pulverizing barrel.

[0011] Preferably, the nozzle is threadedly connected to the body, the nozzle is a Laval nozzle, and a through hole with large ends and a small middle is opened in the center of the nozzle.

[0012] Further preferably, the end of the through hole away from the axis of the grinding cylinder is a round chamfer with a radius of 4.5 to 5 mm, and the end of the through hole close to the axis of the grinding cylinder is a bell mouth that gradually opens outward, and the opening angle of the bell mouth is 10 to 12°.

[0013] Further preferably, the length of the bell mouth is 75 to 80% of the total length of the through hole.

[0014] Further preferably, the opening angle refers to the angle between two busbars of the bell mouth symmetrically distributed on both sides of the axis of the through hole.

[0015] Preferably, there are two first nozzles which are evenly distributed around the axis of the straight cylinder, and the second nozzle is coaxially arranged with the conical cylinder.

[0016] Further preferably, the first nozzle is arranged at an angle, and the angle between the axis of the first nozzle and the axis of the second nozzle is 120°.

[0017] Preferably, the inner walls of the straight cylinder and the tapered cylinder are provided with a ceramic coating.

[0018] Preferably, the nozzle, the grading wheel and the discharger are all made of ceramic.

[0019] Due to the application of the above technical solution, the utility model has the following advantages compared with the prior art:

[0020] The utility model provides a small-scale trial airflow pulverizer for positive and negative electrode materials of lithium batteries, comprising a straight cylinder extending in a vertical direction and a crushing cylinder connected to a conical cylinder at the bottom of the straight cylinder, a grading mechanism arranged in the straight cylinder, a feeding hole for feeding materials opened in the middle of the straight cylinder, and a crushing mechanism. By closing the upper end of the straight cylinder, the conical cylinder is in a headless cone shape with a larger upper portion and a smaller lower portion, the crushing mechanism is a nozzle, and the nozzle includes a body inserted on the crushing cylinder and a nozzle connected to the end of the body extending into the inner end of the crushing cylinder, so that the nozzle is divided into a nozzle inserted in the straight cylinder, a nozzle connected to the main body and extending into the inner end of the crushing cylinder, and a grading mechanism arranged in the straight cylinder, a feeding hole for feeding materials opened in the middle of the straight cylinder, and a crushing mechanism. The first nozzle at the lower end and the second nozzle inserted at the bottom of the cone body make the extension line of the axis of the first nozzle intersect with the extension line of the axis of the second nozzle at one point, so that the component materials entering from the feed hole can fall under the action of gravity, be guided to the second nozzle through the inner wall of the cone body, and then be blown upward by the second nozzle. After passing through the intersection point, they are crushed and then screened out by the grading mechanism. The crushing rate of the component materials is high, the residue is small, and no debris is mixed in. It is particularly suitable for the crushing operation of the component materials during the small-scale test of the positive and negative electrode materials of lithium batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a three-dimensional schematic diagram of a preferred embodiment of the utility model. For ease of observation, the closing piece on the top of the straight cylinder is hidden.

[0022] Figure 2 yes Figure 1 Schematic top view of .

[0023] Figure 3 yes Figure 2 Schematic cross-sectional view in the AA direction.

[0024] Figure 4 yes Figure 1 A three-dimensional schematic diagram of the lower end of the straight cylinder and the tapered cylinder.

[0025] Figure 5 yes Figure 4 Schematic top view of .

[0026] Figure 6 yes Figure 5 Schematic cross-sectional view in the BB direction.

[0027] Among them: 10. Crushing cylinder; 11. Straight cylinder; 12. Conical cylinder; 21. Classifying wheel; 22. Discharger; 30. Feed hole; 40a. First nozzle; 40b. Second nozzle; 41. Main body; 411. Nut; 42. Nozzle; 421. Through hole; 422. Bell mouth. DETAILED DESCRIPTION

[0028] The preferred embodiments of the present utility model are described in detail below with reference to the accompanying drawings.

[0029] like Figures 1 to 6As shown, the utility model provides a small-scale airflow pulverizer for lithium battery positive and negative electrode materials, comprising: a pulverizing cylinder 10, a grading mechanism, a feeding hole 30, and a pulverizing mechanism, wherein the pulverizing cylinder 10 extends in the vertical direction, and the pulverizing cylinder 10 comprises a straight cylinder 11 and a conical cylinder 12 sealed at the bottom of the straight cylinder 11, the upper end of the straight cylinder 11 is closed by a closure member (not shown in the figure), and the conical cylinder 12 is in the shape of a truncated cone with a larger upper portion and a smaller lower portion; the grading mechanism is arranged in the straight cylinder 11, and the grading mechanism comprises a grading wheel 21 rotatably arranged at the upper end of the straight cylinder 11 and a discharger 22 coaxially arranged with the grading wheel 21, the discharger 22 is cylindrical, and the discharger 22 is fixed to the straight cylinder body 11; a feed hole 30 is opened in the middle of the straight cylindrical body 11, and the feed hole 30 is used to feed the component materials to be crushed into the pulverizing cylinder 10; the pulverizing mechanism is a nozzle, and the nozzle includes a body 41 inserted on the pulverizing cylinder 10 and a nozzle 42 connected to the body 41 and extending into the inner end of the pulverizing cylinder 10, and the nozzle is divided into a first nozzle 40a inserted at the lower end of the straight cylindrical body 11 and a second nozzle 40b inserted at the bottom of the conical cylindrical body 12. There are two first nozzles 40a and they are evenly distributed around the axis of the straight cylindrical body 11, and the second nozzle 40b is coaxially arranged with the conical cylindrical body 12. The extension line of the axis of the first nozzle 40a and the extension line of the axis of the second nozzle 40b intersect at one point.

[0030] The advantage of this arrangement is that the component materials entering from the feed hole can fall under the action of gravity, be guided to the second nozzle through the inner wall of the cone, and then be blown upward by the second nozzle. After passing through the intersection of the extended lines of the axis of the first nozzle and the second nozzle, they are crushed by the air flow, and then screened out by the grading mechanism. The component materials have a high crushing rate, little residue, and will not be mixed with debris. It is particularly suitable for the crushing operation of component materials during small-scale tests of positive and negative electrode materials of lithium batteries.

[0031] To facilitate connection and ventilation, in this embodiment, the main body 41 is in the shape of a hollow screw, and a nut 411 is provided on its outer periphery and threadedly connected to it for locking the main body 41 on the grinding barrel 10. Furthermore, the nozzle 42 is threadedly connected to the main body 41. The nozzle 42 is in the shape of a hollow plug, which is threadedly connected to the center hole of the main body 41. The nozzle 42 is a Laval nozzle, and a through hole 421 with large ends and a small middle is opened in the center of the nozzle 42.

[0032] In order to adapt to the crushing of positive and negative electrode materials of lithium batteries and obtain the best crushing effect, further, the end of the through hole 421 close to the axis of the crushing cylinder 10 is a round chamfer with a radius of 4.5 to 5 mm, and the end of the through hole 421 away from the axis of the crushing cylinder 10 is a bell mouth 422 that gradually opens outward. The opening angle of the bell mouth 422 is preferably 10 to 12°. The opening angle refers to the angle between the two busbars of the bell mouth 422 symmetrically distributed on both sides of the axis of the through hole 421. In this embodiment, the angle is 11°. At the same time, the length of the bell mouth 422 is also very important. The length is preferably 75 to 80% of the total length of the through hole 421. In this embodiment, the length is 77% of the total length of the through hole 421. The aperture of the through hole 421 and the inner diameter of the straight cylinder 10 and the size of the conical cylinder 12 can be selected according to the crushing amount of the component material and the particle size of the incoming material, and no limitation is made here.

[0033] To further enhance the crushing effect, in this embodiment, the first nozzle 40 a is tilted, and the angle between the axis of the first nozzle 40 a and the axis of the second nozzle 40 b is 120°.

[0034] In order to further prevent debris from mixing in, the inner walls of the straight cylinder 11 and the conical cylinder 12 are provided with a ceramic coating. At the same time, the nozzle, the grading wheel 21 and the discharger 22 are all made of ceramic.

[0035] It should be noted that the height of the second nozzle 40b protruding from the bottom surface of the cone body 12 cannot be too high, and is usually controlled to be 3 to 5 mm to avoid forming an excessively large dead zone at the bottom of the cone body 12, which affects the residual amount.

[0036] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A small-scale airflow mill for lithium battery positive and negative electrode materials, comprising: A pulverizing cylinder extending in a vertical direction, comprising a straight cylinder and a conical cylinder connected to the bottom of the straight cylinder, wherein the upper end of the straight cylinder is closed and the conical cylinder is in the shape of a truncated cone with a larger upper portion and a smaller lower portion; A grading mechanism, the grading mechanism is arranged in the straight cylinder, the grading mechanism includes a grading wheel rotatably arranged at the upper end of the straight cylinder and a discharger coaxially arranged with the grading wheel, the discharger is cylindrical and fixed to the straight cylinder; A feed hole is provided in the middle of the straight cylinder, and is used to feed the component materials to be crushed into the crushing cylinder; Crushing mechanism; Its characteristics are: The pulverizing mechanism is a nozzle, which includes a main body inserted on the pulverizing cylinder and a nozzle connected to the main body and extending into the inner end of the pulverizing cylinder. The nozzle is divided into a first nozzle inserted at the lower end of the straight cylinder and a second nozzle inserted at the bottom of the conical cylinder. The extension line of the axis of the first nozzle and the extension line of the axis of the second nozzle intersect at one point.

2. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 1, characterized in that: The body is threadedly connected with a nut for locking the body on the grinding cylinder.

3. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 1, characterized in that: The nozzle is threadedly connected to the body. The nozzle is a Laval nozzle. A through hole with large ends and a small middle is provided in the center of the nozzle.

4. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 3, characterized in that: The end of the through hole away from the axis of the grinding cylinder is a round chamfer with a radius of 4.5 to 5 mm, and the end of the through hole close to the axis of the grinding cylinder is a bell mouth that gradually opens outward, and the opening angle of the bell mouth is 10 to 12°.

5. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 4, characterized in that: The length of the bell mouth is 75 to 80% of the total length of the through hole.

6. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 4, characterized in that: The opening angle refers to the angle between two busbars of the bell mouth symmetrically distributed on both sides of the axis of the through hole.

7. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 1, characterized in that: There are two first nozzles which are evenly distributed around the axis of the straight cylinder, and the second nozzle is coaxially arranged with the conical cylinder.

8. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 7, characterized in that: The first nozzle is arranged at an angle, and the angle between the axis of the first nozzle and the axis of the second nozzle is 120°.

9. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 1, characterized in that: The inner walls of the straight cylinder and the tapered cylinder are provided with ceramic coatings.

10. The small-scale airflow pulverizer for lithium battery positive and negative electrode materials according to claim 1, characterized in that: The nozzle, the grading wheel and the discharger are all made of ceramics.

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