A new electrode feeding system

Abstract

The utility model discloses a novel electrode feeding system, including a slurry storage tank; the discharge port of the slurry storage tank is connected to the feed port of the coating slurry buffer tank through a feed valve and a slurry feed pipeline in which a feed pump, a filter and a slurry feed solenoid valve are sequentially arranged; the discharge port of the coating slurry buffer tank is respectively connected to the first branch pipeline and the second branch pipeline through the coating feed pipeline; the other end of the feed valve is connected to the first inflation port through the first pressure-maintaining valve; the first branch pipeline is connected to the second pressure-maintaining valve; the second pressure-maintaining valve is connected to the second inflation port; the second branch pipeline is connected to the feed port of the feeding screw pump; the discharge port of the feeding screw pump is connected to the die head through a connecting pipeline in which a second filter and a coating gap valve are sequentially arranged; a first pressure gauge is installed between the feed valve and the first pressure-maintaining valve; and a second pressure gauge is installed on the first branch pipeline. The utility model can perform airtightness test on the sealing of the battery pole piece feeding system in advance to ensure the safety of battery production.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium ion battery pole piece production, in particular to a novel electrode feeding system. Background Art

[0002] At present, lithium-ion batteries have the advantages of high specific energy, many cycles and long storage time. They are not only widely used in portable electronic devices (such as mobile phones, digital cameras and laptops), but also widely used in large and medium-sized electric equipment such as electric vehicles, electric bicycles and electric tools. Therefore, the safety requirements for lithium-ion batteries are getting higher and higher.

[0003] During the production process of battery pole pieces, if there is an air leakage problem in the feeding system from the powder slurry of the battery pole piece to the coating die head, air will enter the slurry (i.e., the pole piece active material slurry), forming bubbles in the slurry. Finally, when the slurry is applied to the surface of the battery pole piece, the bubbles will burst and form pits on the surface of the battery pole piece. The active material in the pits is reduced, and in severe cases, there is even no active material in the center of the pit, resulting in the exposure of the pole piece current collector. Among them, the appearance of bubble pits in the positive pole piece will lead to loss of battery capacity, and the appearance of bubble pits in the negative pole piece will cause lithium precipitation problems, affecting the safety and reliability of the battery.

[0004] Therefore, there is an urgent need to develop a technology that can take preventive measures during the production process of battery electrodes to conduct an airtightness test on the sealing of the battery electrode slurry to the coating die feeding system in advance, so that the feeding system that meets the airtightness requirements can feed the slurry to the coating process of the battery electrode, thereby avoiding battery product defects caused by the introduction of gas into the slurry after feeding. Utility Model Content

[0005] The purpose of the utility model is to provide a novel electrode feeding system in view of the technical defects in the prior art.

[0006] To this end, the utility model provides a novel electrode feeding system, which includes a hollow slurry storage tank;

[0007] The bottom discharge port of the slurry storage tank is connected to one end of the feed valve through a hollow connecting pipe;

[0008] The other end of the feeding valve is connected to the feeding port at the left end of the coating slurry buffer tank through a slurry feeding pipeline which is provided with a feeding pump, a filter and a slurry feeding solenoid valve in sequence;

[0009] The discharge port at the bottom of the coating slurry buffer tank is connected to one end of a coating feed pipeline;

[0010] The other end of the coating supply pipeline is connected to one end of the first branch pipeline and one end of the second branch pipeline respectively;

[0011] The other end of the feed valve is also connected to one end of the first pressure-maintaining valve;

[0012] The other end of the first pressure-maintaining valve is connected to the first inflation port;

[0013] The other end of the first branch pipeline is connected to one end of the second pressure-maintaining valve;

[0014] The other end of the second pressure-maintaining valve is connected to the second inflation port;

[0015] The other end of the second branch pipeline is connected to the feed inlet of the feed screw pump;

[0016] The discharge port of the feeding screw pump is connected to the slurry feeding port on the die head through a connecting pipe which is provided with a second filter and a coating gap valve in sequence;

[0017] Wherein, a first pressure gauge is installed on the connecting pipe between the feeding valve and the first pressure maintaining valve;

[0018] A second pressure gauge is installed on the first branch pipeline.

[0019] It can be seen from the technical solution provided by the utility model above that, compared with the prior art, the utility model provides a new type of electrode feeding system, which is scientifically designed and can take preventive measures in the production process of battery pole pieces. It can perform an airtightness test on the sealing of the feeding system (i.e., the powder slurry of the battery pole piece to the coating die head feeding system) in advance, so that the feeding system that meets the airtightness requirements can feed the slurry to the coating process of the battery pole piece, thereby avoiding battery product defects caused by the introduction of gas into the slurry after feeding, ensuring the safety and reliability of battery production, and having great practical significance.

[0020] By applying the electrode feeding system provided by the utility model, it is possible to conveniently, safely and reliably feed the die head used for coating the slurry on the surface of the electrode piece, thereby ensuring the quality and efficiency of the feeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 A schematic diagram of the structure of a novel electrode feeding system provided by the utility model;

[0022] Figure 2 In one embodiment of a novel electrode feeding system provided by the utility model, after the first pressure-maintaining valve is closed and the pressure is maintained for 10 minutes, the pipeline pressure-time curve graph collected by the first pressure gauge;

[0023] In the figure, 1, slurry storage tank; 2, feeding valve; 3, first pressure gauge; 4, first charging port; 5, first pressure maintaining valve;

[0024] 6. Feeding pump; 7. Slurry feeding pipeline; 8. First filter; 9. Slurry feeding solenoid valve; 10. Coating slurry buffer tank;

[0025] 11. Coating slurry discharge valve; 12. Coating supply pipeline; 13. Second pressure gauge; 14. Second air charging port; 15. Second pressure maintaining valve;

[0026] 16. Feed screw pump; 17. Second filter; 18. Coating gap valve; 19. Die head; 20. Display. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0028] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0029] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0031] See also Figure 1 The utility model provides a novel electrode feeding system, which is a novel slurry to coating die feeding system. The system can detect the air tightness of the feeding system while realizing reliable slurry feeding. The system includes a hollow slurry storage tank 1;

[0032] The bottom discharge port of the slurry storage tank 1 is connected to one end of the feed valve 2 through a hollow connecting pipe;

[0033] The other end of the feeding valve 2 is connected to the feed port at the left end of the coating slurry buffer tank 10 through a slurry feeding pipeline 7 which is provided with a feeding pump 6, a filter 8 and a slurry feeding solenoid valve 9 in sequence;

[0034] The discharge port at the bottom end of the coating slurry buffer tank 10 is connected to one end of a coating feed pipe 12;

[0035] The other end of the coating supply pipeline 12 is connected to one end of the first branch pipeline 121 and one end of the second branch pipeline 122 respectively;

[0036] The other end of the feed valve 2 is also connected to one end of the first pressure-maintaining valve 5;

[0037] The other end of the first pressure-maintaining valve 5 is connected to the first inflation port 4;

[0038] The other end of the first branch pipe 121 is connected to one end of the second pressure-maintaining valve 15;

[0039] The other end of the second pressure-maintaining valve 15 is connected to the second inflation port 14;

[0040] The other end of the second branch pipeline 122 is connected to the feed port of the feed screw pump 16;

[0041] The discharge port of the feeding screw pump 16 is connected to the slurry feeding port on the die head 19 through a connecting pipe on which a second filter 17 and a coating gap valve 18 are sequentially arranged.

[0042] Wherein, a first pressure gauge 3 is installed on the connecting pipe between the feed valve 2 and the first pressure-maintaining valve 5;

[0043] A second pressure gauge 13 is installed on the first branch pipeline 121;

[0044] It should be noted that the first pressure gauge 3 is used to measure the pressure in the connecting pipe between the feeding valve 2 and the first pressure-maintaining valve 5 and the slurry feeding pipe 7. The second pressure gauge 13 is used to measure the pressure in the first branch pipe 121 and the coating feeding pipe 12.

[0045] In the present utility model, in specific implementation, the discharge port at the right end of the feed pump 6 is connected to the feed port of the filter 8;

[0046] The discharge port of the filter 8 is connected to one end of the slurry feeding electromagnetic valve 9;

[0047] The other end of the slurry feeding electromagnetic valve 9 is communicated with the feed port at the left end of the coating slurry buffer tank 10 .

[0048] In the present utility model, in specific implementation, the first charging port 4 and the second charging port 14 are respectively connected to the compressed air outlet of an air booster pump;

[0049] The air booster pump is used to provide compressed air to the first air charging port 4 and the second air charging port 14 .

[0050] In the present invention, in a specific implementation, the other end of the coating supply pipeline 12 is connected to a first interface of a three-way joint;

[0051] The second interface and the third interface of the three-way joint are connected to one end of the first branch pipe 121 and one end of the second branch pipe 122 respectively.

[0052] In the present utility model, in specific implementation, the cross-sectional area of ​​the slurry storage tank 1 gradually decreases from top to bottom.

[0053] In the present utility model, in a specific implementation, the lower part of the slurry storage tank 1 is in a hemispherical shape.

[0054] In the present invention, in a specific implementation, the cross-sectional area of ​​the coating slurry buffer tank 10 gradually decreases from top to bottom.

[0055] In the present utility model, in a specific implementation, the front view shape of the coating slurry buffer tank 10 is an inverted pentagon, the upper half of which is a rectangle, and the lower half is an inverted triangle (isosceles triangle).

[0056] In the present invention, in a specific implementation, the first pressure gauge 3 and the second pressure gauge 13 can be pressure gauges with a pressure value display function.

[0057] In the present utility model, in specific implementation, the detection data output terminal of the first pressure gauge 3 is connected to the first data acquisition input terminal on the display 20;

[0058] The detection data output terminal of the second pressure gauge 13 is connected to the second data acquisition input terminal on the display 20;

[0059] The display 20 is used to display the internal pressure data of the pipeline measured by the first pressure gauge 3 and the second pressure gauge 13 to achieve visual display.

[0060] In order to more clearly understand the technical solution of the present utility model, the functions of each component are described below.

[0061] Slurry storage tank 1, used to store slurry to ensure continuous and stable supply for coating;

[0062] Feed valve 2 is used to close the feed valve when the stored slurry is used up to avoid empty beating.

[0063] The first pressure gauge 3 is used to test the compressed air pressure of the slurry feeding section and the pressure change trend over time;

[0064] The first air filling port 4 is used as a connection port of an external air filling device to fill compressed air into the slurry feeding pipeline 7;

[0065] The first pressure-maintaining valve 5 is used to fill compressed air when it is opened, and to prevent the compressed air inside the slurry feeding pipeline 7 from leaking from the first inflation port 4 when it is closed;

[0066] The feed pump 6 is used to deliver slurry to the coating slurry buffer tank 10, and can further start running when the slurry liquid level reaches the lower limit of the feed according to the liquid level signal of the coating slurry buffer tank 10, and stop running when the slurry liquid level reaches the upper limit of the feed;

[0067] A first filter 8, for coarsely filtering particles in the slurry;

[0068] The slurry feeding solenoid valve 9 is used to, according to the liquid level signal of the coating slurry buffer tank 10, when the slurry liquid level reaches the lower limit of the feeding, the feeding pump 6 starts to run, at this time the slurry feeding solenoid valve 9 opens, and the slurry enters the coating feeding system from the slurry feeding system; when the slurry liquid level reaches the upper limit of the feeding, the feeding pump 6 stops running, at this time the slurry feeding solenoid valve 9 closes, and the slurry stops entering the coating feeding system from the slurry feeding system;

[0069] The coating slurry buffer tank 10 is used to buffer the slurry and maintain a stable liquid level, and to supply the slurry to the coating die (i.e., the die 19 used to coat the slurry onto the surface of the battery pole piece) through the feeding screw pump 16;

[0070] The coating slurry discharge valve 11 is used for initial feeding. When the coating slurry buffer tank 10 is filled from an empty tank to the upper limit of the liquid level, the coating slurry discharge valve 11 is opened and the feeding screw pump 16 is started, so that the slurry fills the coating feeding system and enters the die head 19;

[0071] The second pressure gauge 13 is used to test the compressed air pressure of the coating feeding section and the pressure change trend over time;

[0072] The second air filling port 14 is used as an external air filling device to fill compressed air into the connection port of the coating supply pipe 12;

[0073] The second pressure-maintaining valve 15 is used to fill compressed air when it is opened, and to prevent the compressed air inside the coating supply pipeline 12 from leaking from the second air filling port 14 after it is closed;

[0074] The feeding screw pump 16 is used to stably supply the slurry to the die head 19 at a certain rotation speed according to the slurry discharge amount required for coating the electrode piece;

[0075] The second filter 17 is used for fine filtering of particles in the slurry;

[0076] The coating gap valve 18 is used to control the opening and closing of the valve so that the slurry extruded from the die head 19 forms a periodic coating area and a non-coating blank area of ​​a set size on the surface of the battery electrode current collector;

[0077] The die head 19 is the original die head of the battery pole piece slurry coating equipment, which is used to coat the slurry on the battery pole piece current collector by extrusion to manufacture the pole piece;

[0078] The display 20 is used to receive the electrical signal from the coating equipment and display it visually.

[0079] In terms of specific implementation, the first pressure gauge 3 and the second pressure gauge 13 can be finished modules with mature existing technologies. For example, a Keyence industrial pressure transmitter model PMS120 produced by Keyence (China) Co., Ltd. can be used. It has a pressure value display function and can transmit the pressure signal to a display, on which the pressure fluctuation trend can be displayed over time.

[0080] In a specific implementation, the first pressure-maintaining valve 5 and the second pressure-maintaining valve 15 can be finished modules with mature existing technologies. For example, a sanitary quick-connect ball valve with a model of φ19*34 produced by Misumi can be used.

[0081] In specific implementation, the first filter 8 can be a finished product module with mature existing technology, for example, a 150-mesh metal mesh filter produced by Buhler China Investment Co., Ltd. can be used;

[0082] The second filter 17 may be a finished product module with mature prior art, for example, a capsule filter of model RK12-20HC75 produced by Cobetter Filter Equipment Co., Ltd.

[0083] In specific implementation, the feed screw pump 16 can be a finished product module with mature existing technology, for example, a feed screw pump model NHL30FF produced by Hyoshin Equipment Co., Ltd. can be used.

[0084] In specific implementation, the coating gap valve 18 can be a finished product module with mature existing technology, for example, a coating gap valve that is equipped with a coating machine of model CLSC-150L40D produced by Haoneng Technology Co., Ltd.

[0085] In a specific implementation, the die head 19 can be a finished product module with mature existing technology, for example, a slurry coating die head provided with a coating machine of model CLSC-150L40D produced by Haoneng Technology Co., Ltd.

[0086] In a specific implementation, the display 20 may be a finished product module with mature existing technology, for example, a touch display screen with model number TP1200 6AV2124-0MC01-0AX0 produced by Siemens China.

[0087] In order to more clearly understand the technical solution of the present utility model, the working principle of the present utility model is explained below in conjunction with specific embodiments.

[0088] Example

[0089] The first step, such as Figure 1 As shown, before the slurry is supplied, the feeding system provided by the utility model (i.e., the slurry to coating die feeding system) is in a clean and hollow state;

[0090] In the second step, the outlet valve (i.e., the feed valve 2) of the slurry storage tank 1 and the slurry feed solenoid valve 9 are closed, and compressed air is charged into the slurry feed pipeline 7 through the first air charging port 4. When the pressure reaches 400 kPa, the first pressure-maintaining valve 5 is closed, and the pipeline pressure is tested by the first pressure gauge 3. The pressure is maintained for 10 minutes, and the pressure data displayed on the display 20 is observed (for example, it can be expressed in the form of a pressure-time curve). There is no pressure drop or the pressure drop amplitude is less than a certain value (for example, a standard value of 5 kPa). Figure 2 As shown, it means that the air tightness of the corresponding pipeline is qualified and can meet the production requirements. This operation tests the air tightness of the slurry feeding part in the feeding system;

[0091] In the third step, close the coating slurry discharge valve 11 and the coating gap valve 18, and fill the coating feed pipe 12 with compressed air through the second inflation port 14. When the pressure reaches 400 kPa, close the second pressure maintaining valve 15, and test the pipeline pressure through the second pressure gauge 13. After maintaining the pressure for 10 minutes, observe the pressure data displayed on the display 20 (for example, it can be expressed in the form of a pressure-time curve). If there is no pressure drop or the pressure drop is less than a certain value (for example, the standard value of 5 kPa), it means that the air tightness of the corresponding pipeline is qualified and can meet the production requirements. This operation tests the air tightness of the coating feed part in the feed system.

[0092] Regarding the second and third steps above, if the pressure drop amplitude exceeds the standard value, the staff needs to conduct a comprehensive test on the air tightness of the entire feeding system. For example, starting from the connection at the end of the pipeline, remove the clamps used for each connection, install the blind plate (i.e. flange cover), and repeat the above leak detection work to locate the leaking area, and use bubble water to find the location of the leak, and retest the air tightness after maintenance.

[0093] Regarding the second and third steps mentioned above, if the pressure drop amplitude values ​​obtained by the two pressure gauges are both less than the standard values, the test is completed, the pipeline valve (specifically the first pressure maintaining valve 5 and the second pressure maintaining valve 15) is opened to release the compressed air, and the subsequent slurry supply operation is continued. The above measurements can effectively reduce the problem of gas introduction into the slurry due to leakage points caused by improper pipeline installation or long-term deformation of the clamp gasket at the connection position, and ultimately effectively prevent and avoid pits on the electrode surface due to the rupture of bubbles in the slurry during the coating process.

[0094] Compared with the prior art, the novel electrode feeding system provided by the utility model has the following beneficial effects:

[0095] 1. The utility model is designed with an airtightness measurement structure, which can quantitatively measure the sealing effect of the battery pole piece slurry to the coating and feeding system.

[0096] 2. The utility model can test the air tightness of the feeding system by adding a pressure structure (such as an air booster pump, a first inflation port and a second inflation port), installing a pressure-maintaining valve to maintain pressure, and installing pressure gauges at different positions.

[0097] 3. In the present invention, two pressure gauges are connected to a display, through which the pipeline pressure data detected by the pressure gauge can be displayed. When the pressure drop in the pipeline is greater than a certain value (for example, the standard value of 5kpa), it can be considered that the air tightness of the feeding system is unqualified. Then, the staff will re-test and leak-check each connection part and equipment in the feeding system to overcome the leaking position, and then test it again with a pressure gauge. When there is no pressure drop in the pipeline or the pressure drop is less than a certain value (for example, the standard value of 5kpa), it means that the air tightness of the feeding system is qualified.

[0098] 4. The feeding system provided by the utility model can detect whether there is a loose seal at the connection in the case of an empty pipe by filling compressed air and measuring the pressure value, and perform processing before feeding to prevent air from entering the slurry through the sealing defects after feeding. Through the high-precision digital pressure value display, this system can quickly and efficiently detect pipeline leakage points. Through prior prevention, the probability of electrode defects is greatly reduced, saving production costs.

[0099] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A new type of electrode feeding system, characterized in that: It comprises a hollow slurry storage tank (1); The bottom discharge port of the slurry storage tank (1) is connected to one end of the feed valve (2) through a hollow connecting pipe; The other end of the feeding valve (2) is connected to the feeding port at the left end of the coating slurry buffer tank (10) through a slurry feeding pipeline (7) which is provided with a feeding pump (6), a filter (8) and a slurry feeding electromagnetic valve (9) in sequence; The discharge port at the bottom end of the coating slurry buffer tank (10) is connected to one end of a coating supply pipeline (12); The other end of the coating supply pipeline (12) is respectively connected to one end of the first branch pipeline (121) and one end of the second branch pipeline (122); The other end of the feed valve (2) is also connected to one end of the first pressure-maintaining valve (5); The other end of the first pressure-maintaining valve (5) is connected to the first inflation port (4); The other end of the first branch pipe (121) is connected to one end of the second pressure-maintaining valve (15); The other end of the second pressure-maintaining valve (15) is connected to the second inflation port (14); The other end of the second branch pipe (122) is connected to the feed inlet of the feed screw pump (16); The discharge port of the feeding screw pump (16) is connected to the slurry feeding port on the die head (19) through a connecting pipe which is provided with a second filter (17) and a coating gap valve (18) in sequence; Wherein, a first pressure gauge (3) is installed on the connecting pipe between the feed valve (2) and the first pressure-maintaining valve (5); A second pressure gauge (13) is installed on the first branch pipeline (121).

2. The novel electrode feeding system according to claim 1, characterized in that: The discharge port at the right end of the feed pump (6) is connected to the feed port of the filter (8); The discharge port of the filter (8) is connected to one end of the slurry feeding electromagnetic valve (9); The other end of the slurry feeding electromagnetic valve (9) is connected to the feed port at the left end of the coating slurry buffer tank (10).

3. The novel electrode feeding system according to claim 1, characterized in that: The first air charging port (4) and the second air charging port (14) are respectively connected to a compressed air outlet of an air booster pump; The air booster pump is used to provide compressed air to the first air charging port (4) and the second air charging port (14).

4. The novel electrode feeding system according to claim 1, characterized in that: The other end of the coating supply pipeline (12) is connected to a first interface of a three-way joint; The second interface and the third interface of the three-way joint are respectively connected to one end of the first branch pipeline (121) and one end of the second branch pipeline (122).

5. The novel electrode feeding system according to claim 1, characterized in that: The cross-sectional area of ​​the slurry storage tank (1) gradually decreases from top to bottom.

6. The novel electrode feeding system according to claim 1, characterized in that: The lower part of the slurry storage tank (1) is in a hemispherical shape.

7. The novel electrode feeding system according to claim 1, characterized in that: The cross-sectional area of ​​the coating slurry buffer tank (10) gradually decreases from top to bottom.

8. The novel electrode feeding system according to claim 1, characterized in that: The front view of the coating slurry buffer tank (10) is an inverted pentagon, the upper half of which is a rectangle and the lower half is an inverted triangle.

9. The novel electrode feeding system according to any one of claims 1 to 8, characterized in that: The detection data output terminal of the first pressure gauge (3) is connected to the first data acquisition input terminal on the display (20); The detection data output terminal of the second pressure gauge (13) is connected to the second data acquisition input terminal on the display (20).

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