CN213727533U - Control system and coating machine for surface density of battery pole piece - Google Patents
Control system and coating machine for surface density of battery pole piece Download PDFInfo
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- CN213727533U CN213727533U CN202022127274.0U CN202022127274U CN213727533U CN 213727533 U CN213727533 U CN 213727533U CN 202022127274 U CN202022127274 U CN 202022127274U CN 213727533 U CN213727533 U CN 213727533U
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
- Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
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Abstract
The utility model belongs to the technical field of the lithium cell, especially, relate to a control system and coating machine of battery pole piece areal density, wherein the control system of battery pole piece areal density includes coating die head, controller, valve and a plurality of pressure sensor. The coating die head comprises an upper die, a lower die and a die cavity, a valve is communicated with the die cavity through a feeding pipeline, a plurality of pressure sensors are arranged in the die cavity along the extending direction of the die cavity, the pressure sensors and the valve are respectively electrically connected with a controller, and the controller is used for controlling the opening degree of the valve according to whether the pressure difference of the adjacent pressure sensors exceeds a preset pressure difference threshold value. The embodiment of the utility model provides an in, after the controller received the pressure signal who changes, judge whether the pressure differential fluctuation of any two adjacent pressure sensor is in the within range, if pressure differential has surpassed preset pressure differential threshold value, controller automatically regulated the aperture of valve changes the thick liquids velocity of import to this reaches the purpose of full automatically regulated thick liquids flow field distribution homogeneity, thereby guarantees the uniformity of the horizontal surface density of coating.
Description
Technical Field
The utility model belongs to the technical field of the lithium cell, especially, relate to a control system and coating machine of battery pole piece areal density.
Background
At present, the positive and negative pole pieces of the lithium battery are mostly coated in an extrusion mode, a coating die head is an important part of a coating machine, and coating liquid is extruded and sprayed out along a gap of the coating die head under certain pressure and coated on a base material.
In the coating process of the lithium ion battery pole piece, the slurry needs to be filtered due to the existence of particles in the slurry, and the flow rate of the slurry is gradually reduced due to the increase of the filtering pressure, so that the longitudinal (parallel to the advancing direction of the base material) surface density is gradually reduced. Meanwhile, the coating slurry is a non-Newtonian fluid, the viscosity of the coating slurry is influenced by various factors, the fluctuation range is large, and the fluctuation of the surface density in the transverse direction (vertical to the advancing direction of the substrate) is also brought. In the prior art, no effective measures are provided for improving pressure fluctuation in a die head caused by slurry property change, so that the surface density of a pole piece in the coating process is easily uneven, and the performance of a lithium battery is further influenced.
SUMMERY OF THE UTILITY MODEL
The utility model discloses the technical problem that will solve is: aiming at the problem of uneven surface density of a pole piece in the coating process in the prior art, a control system of the surface density of the battery pole piece and a coating machine are provided.
In order to solve the above technical problem, an embodiment of the present invention provides a system for controlling the areal density of a battery plate, which includes a coating die head, a valve, a plurality of pressure sensors, and a controller for controlling the opening degree of the valve;
the coating die head comprises an upper die, a lower die and a die cavity formed between the upper die and the lower die, the valve is communicated with the die cavity through a feeding pipeline, a plurality of pressure sensors are arranged in the die cavity at intervals along the extending direction of the die cavity, and the pressure sensors and the valve are respectively electrically connected with the controller.
Optionally, a slit channel between the upper die and the lower die is provided at the front side of the coating die head, the slit channel is communicated with the die cavity, and an included angle between a line connecting the pressure sensor and an inlet of the slit channel and a horizontal central line of the die cavity is 0-45 °.
Optionally, an upper die cavity is arranged at the lower part of the upper die, the opening of the upper die cavity faces downwards, a lower die cavity is arranged at the upper part of the lower die, the opening of the lower die cavity faces upwards, when the upper die and the lower die are closed, the upper die cavity and the lower die cavity are matched to form the die cavity, and the pressure sensor is arranged in the lower die cavity.
Optionally, a plurality of said pressure sensors are located on the same horizontal line.
Optionally, a plurality of the pressure sensors are arranged at equal intervals along the extending direction of the mold cavity.
Optionally, the control system further comprises a feed pump electrically connected to the controller, and the controller is further configured to control the output power of the feed pump.
Optionally, the feed pump is connected to the feed conduit, and the valve is located between the feed pump and the coating die.
Optionally, the control system further includes a winding motor electrically connected to the controller, and the controller is further configured to control a rotation speed of the winding motor.
Optionally, the control system further includes an emptying roller, a winding roller, and a base material for coating the slurry, the base material is wound between the emptying roller and the winding roller, and the winding roller motor drives the winding roller and the emptying roller to rotate so as to control the traveling speed of the base material.
On the other hand, the embodiment of the utility model provides a coating machine, include as before the control system of battery pole piece areal density.
In the embodiment of the utility model, a plurality of pressure sensors are arranged in the die cavity along the extending direction of the die cavity and used for monitoring the pressure change in the die cavity, when the property of the slurry changes, the flow field distribution in the whole coating system changes correspondingly, and the pressure distribution in the coating die head also changes correspondingly, after the controller receives the changed pressure signal, the controller judges whether the pressure difference fluctuation of any two adjacent pressure sensors is in a reasonable range, if the pressure difference exceeds a preset pressure difference threshold value, according to a preset program instruction, the controller automatically adjusts the opening degree of the valve to change the slurry inlet flow rate, the process is continuously carried out at a certain frequency, and the feedback adjustment enables the proper slurry flow rate to be matched under the new slurry flowing state so as to meet the pressure distribution condition in the coating die head, therefore, the aim of fully automatically adjusting the distribution uniformity of the slurry flow field is achieved, and the consistency of the transverse surface density of coating is ensured.
Drawings
Fig. 1 is a schematic diagram of a system for controlling the areal density of a battery pole piece according to an embodiment of the present invention;
fig. 2 is a schematic cross-sectional view of a coating die provided by an embodiment of the present invention;
fig. 3 is a schematic diagram of a distribution of pressure sensors within a coating die provided by an embodiment of the present invention;
fig. 4 is a schematic signal feedback diagram of a control system for controlling the areal density of a battery pole piece according to an embodiment of the present invention.
The reference numerals in the specification are as follows:
1. a coating die head; 2. a controller; 3. a valve; 4. a pressure sensor; 5. an upper die; 6. a lower die; 7. a mold cavity; 8. a feed conduit; 9. a slit passage; 10. an upper mold cavity; 11. a lower die cavity; 12. a feed pump; 13. a roller motor; 14. a discharge roller; 15. a material rolling roller; 16. a substrate.
Detailed Description
In order to make the technical problem, technical solution and advantageous effects solved by the present invention more clearly understood, the following description is given in conjunction with the accompanying drawings and embodiments to illustrate the present invention in further detail. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
As shown in fig. 1 to 4, in one aspect, an embodiment of the present invention provides a system for controlling the areal density of a battery plate, which includes a coating die 1, a valve 3, a plurality of pressure sensors 4, and a controller 2 for controlling the opening degree of the valve 3.
The coating die head 1 comprises an upper die 5, a lower die 6 and a die cavity 7 formed between the upper die 5 and the lower die 6, wherein the die cavity 7 is used for containing coating slurry. The valve 3 is communicated with the die cavity 7 through a feeding pipeline 8, the pressure sensors 4 are arranged in the die cavity 7 along the extension direction of the die cavity 7, the pressure sensors 4 and the valve 3 are respectively electrically connected with the controller 2, the controller 2 is used for controlling the opening degree of the valve 3 according to whether the pressure difference of the adjacent pressure sensors 4 exceeds a preset pressure difference threshold value, and the flow rate of slurry entering the die cavity 7 from the feeding pipeline 8 is controlled by controlling the opening degree of the valve 3.
The pressure sensors 4 are arranged in the die cavity 7 along the extending direction of the die cavity 7 and are used for monitoring pressure change in the die cavity 7, when physical properties such as viscosity and shear stress of slurry are changed due to slurry particle agglomeration or unstable properties of slurry in different batches, flow field distribution in the whole coating system is correspondingly changed, pressure distribution conditions in the coating die head 1 are correspondingly changed, the controller 2 receives a changed pressure signal and judges whether pressure difference fluctuation of any two adjacent pressure sensors 4 is in a reasonable range, if the pressure difference exceeds a preset pressure difference threshold value, the controller 2 automatically adjusts the opening of the valve 3 to change the flow rate of a slurry inlet according to a preset program instruction, and the process is continuously carried out at a certain frequency, feedback adjustment enables a proper slurry flow rate to be matched under a new slurry flowing state so as to enable the slurry flow rate to meet the pressure distribution condition in the coating die head 1, and therefore the purpose of fully automatically adjusting the distribution uniformity of the slurry flow field is achieved, and the consistency of the coating transverse surface density is improved. For example, when the local pressure difference measured by two adjacent pressure sensors 4 is larger than the set value, the viscosity of the slurry is increased. Since the slurry is a shear-thinning non-newtonian fluid, the controller 2 should adjust the valve 3 to moderately increase the flow rate of the slurry to achieve the purpose of reducing the viscosity of the slurry, and finally, the uniformity and stability of the pressure distribution in the mold cavity 7 are ensured.
Compared with the lack of logic of manual regulation, the control system in the embodiment has flexible combination, simple control logic and lower cost. And the controller 2 has the advantages that the parameters are easy to set, and the program can be continuously upgraded and improved in the practical process.
As shown in fig. 3, in an embodiment, to form a reliable pressure difference distribution, at least three pressure sensors 4 are disposed in the mold cavity 7, in order to measure the pressure distribution inside the mold cavity 7, the mold cavity 7 is reasonably segmented according to actual control accuracy and the length of the mold cavity 7, one pressure sensor 4 is disposed in each segment, a pressure difference change value of adjacent segments is used as an adjustment basis, and when the pressure difference change value of any two adjacent segments exceeds a preset pressure difference threshold, the controller 2 automatically adjusts the opening degree of the valve 3 according to a signal fed back by the pressure sensor 4.
The pressure sensor 4 is arranged in the die cavity 7 and can be used as a signal input of the controller 2 and also used for outputting the slurry state to workers in the production process.
In one embodiment, the controller 2 is a programmable controller, and the valve 3 is an electric valve and is electrically connected to the programmable controller, and the programmable controller can control the electric valve to open or close. As shown in fig. 4, the pressure signal monitored by the pressure sensor 4 is transmitted to the programmable controller via an a/D converter, and the programmable controller adjusts the output signal via a D/a converter to adjust the valve 3.
As shown in fig. 2, in an embodiment, a slit channel 9 is provided at a front side of the coating die head 1 and located between the upper die 5 and the lower die 6, the slit channel 9 is communicated with the die cavity 7, an inlet of the slit channel 9 is located in the die cavity 7, the slurry in the die cavity 7 is extruded through the slit channel 9 and coated on a base material 16, and an included angle between a connecting line of the pressure sensor 4 and the inlet of the slit channel 9 and a horizontal center line of the die cavity 7 is 0 ° to 45 °. Preferably, the pressure sensor 4 is provided close to the entrance of the slit passage 9.
In an embodiment, an upper cavity 10 is disposed at a lower portion of the upper mold 5, the upper cavity 10 is opened downward, a lower cavity 11 is disposed at an upper portion of the lower mold 6, the lower cavity 11 is opened upward, when the upper mold 5 and the lower mold 6 are closed, the upper cavity 10 and the lower cavity 11 cooperate to form the cavity 7, and the pressure sensor 4 is disposed at the lower cavity 11. The lower die cavity 11 is provided with a feeding hole communicated with the feeding pipeline 8, slurry enters the die cavity 7 from the feeding hole of the lower die cavity 11, and the pressure sensor 4 is arranged in the lower die cavity 11 and can more accurately sense the pressure change in the die cavity 7.
In an embodiment, the pressure sensors 4 are arranged at equal intervals along the extending direction of the mold cavity 7, so that the pressure difference value between adjacent pressure sensors 4 is not affected by the intervals, and the pressure distribution of different sections in the mold cavity 7 can be accurately controlled. The pressure sensors 4 are located on the same horizontal line in the extending direction of the die cavity 7, the pressure sensors are affected by the flow rate of the slurry in the height direction of the die cavity 7, different pressures can be generated at different heights, and the pressure difference monitored by the adjacent pressure sensors 4 can be prevented from being affected by height change when the pressure sensors 4 are located at the same height.
As shown in fig. 1, in an embodiment, the control system further includes a feed pump 12 electrically connected to the controller 2, the feed pump 12 is configured to control a flow rate of the slurry flowing to the mold cavity 7, preferably, the feed pump 12 is a screw pump, the controller 2 is configured to control an output power of the feed pump 12 according to whether a differential pressure of the adjacent pressure sensor 4 exceeds a preset differential pressure threshold, when the output power of the feed pump 12 is larger, the flow rate of the slurry delivered from the feed pump 12 per unit time is larger, and when the output power of the feed pump 12 is smaller, the flow rate of the slurry delivered from the feed pump 12 per unit time is smaller.
In one embodiment, the feed pump 12 is connected to the feed line 8 and the valve 3 is located between the feed pump 12 and the coating die 1. On the feeding pipe 8, the feeding pump 12 controls the flow of the slurry entering the die cavity 7, so as to influence the surface density of the pole piece in the direction parallel to the advancing direction of the base material 16, and the valve 3 controls the flow speed of the slurry entering the die cavity 7, so as to influence the surface density of the pole piece in the direction perpendicular to the advancing direction of the base material 16.
In one embodiment, the control system further comprises a roller motor 13 electrically connected to the controller 2, and the controller 2 is configured to control the rotation speed of the roller motor 13 according to whether the pressure difference between adjacent pressure sensors 4 exceeds a preset pressure difference threshold, so as to influence the traveling speed of the substrate 16.
As shown in fig. 1, in an embodiment, the control system further includes an unwinding roller 14, a winding roller 15, and a base material 16 for coating the slurry, the slurry in the mold cavity 7 is coated on the base material 16 through the slit passage 9, the base material 16 is wound between the unwinding roller 14 and the winding roller 15, an uncoated base material 16 is wound on the unwinding roller 14, the coated base material 16 is wound on the winding roller 15, the winding roller motor 13 drives the winding roller 15 and the unwinding roller 14 to rotate to control the traveling speed of the base material 16, when the traveling speed of the base material 16 is fast, the thickness of the slurry coated on the base material 16 is thin, and when the traveling speed of the base material 16 is slow, the thickness of the slurry coated on the base material 16 is thick.
As shown in fig. 1 and 4, in one embodiment, the controller 2 has one input interface and three output interfaces, and during the coating process, when the pressure sensor 4 in the mold cavity 7 monitors a changed pressure signal, the monitoring signal of the pressure sensor 4 is transmitted to the controller 2 through an a/D converter and the input interface. According to the signal fed back by the pressure sensor 4, the controller 2 adjusts the output power of the feeding pump 12, the opening degree of the valve 3 and the rotating speed of the roller motor 13 through different output interfaces, the opening degree of the valve 3 is adjusted to enable the transverse surface density to be consistent, meanwhile, the output power of the feeding pump 12 and the rotating speed of the roller motor 13 can be controlled to obtain the advancing speed of the base material 16 matched with the flow of the slurry, the fixing of the coating thickness is guaranteed, the consistency of the longitudinal surface density is guaranteed, and pole pieces with uniform surface density are obtained.
On the other hand, an embodiment of the utility model provides a coating machine, include as before the control system of battery pole piece areal density, control system is the automatic control system who has the negative feedback, and feed pump 12, valve 3 and winding up roller motor 13 are adjusted in the feedback under the program control, pressure sensor 4's pressure signal constantly feeds back with certain sampling frequency, and this accommodation process is repeated until flow field reaches expected homogeneous state in the die cavity 7. Compared with the traditional manual regulation micrometer, the accuracy and reliability of controlling the flow field by changing the coating outlet gap are higher, and the response and execution speed are higher.
The above description is only exemplary of the present invention and should not be taken as limiting the scope of the present invention, as any modifications, equivalents, improvements and the like made within the spirit and principles of the present invention are intended to be included within the scope of the present invention.
Claims (10)
1. A control system for the surface density of a battery pole piece is characterized by comprising a coating die head, a valve, a plurality of pressure sensors and a controller for controlling the opening degree of the valve;
the coating die head comprises an upper die, a lower die and a die cavity formed between the upper die and the lower die, the valve is communicated with the die cavity through a feeding pipeline, a plurality of pressure sensors are arranged in the die cavity at intervals along the extending direction of the die cavity, and the pressure sensors and the valve are respectively electrically connected with the controller.
2. The system for controlling the areal density of the battery plate of claim 1, wherein the front side of the coating die head is provided with a slit passage between the upper die and the lower die, the slit passage communicates with the die cavity, and an angle between a line connecting the pressure sensor and an inlet of the slit passage and a horizontal center line of the die cavity is 0 to 45 °.
3. The system for controlling the areal density of a battery pole piece of claim 2, wherein the lower portion of the upper mold is provided with an upper mold cavity, the upper mold cavity opens downwardly, the upper portion of the lower mold is provided with a lower mold cavity, the lower mold cavity opens upwardly, when the upper and lower molds are closed, the upper and lower mold cavities cooperate to form the mold cavity, and the pressure sensor is disposed in the lower mold cavity.
4. The system for controlling the areal density of the battery plate of claim 1, wherein a plurality of said pressure sensors are located on the same horizontal line.
5. The system for controlling the areal density of the battery plate of claim 1, wherein a plurality of the pressure sensors are arranged at equal intervals along the direction of extension of the mold cavity.
6. The system of any of claims 1-5, further comprising a feed pump in electrical communication with the controller, wherein the controller is further configured to control the output power of the feed pump.
7. The system for controlling areal density of battery plates of claim 6, wherein the feed pump is connected to the feed conduit and the valve is located between the feed pump and the coating die.
8. The system for controlling areal density of battery plates of any of claims 1 to 5, wherein the control system further comprises a roller motor electrically connected to the controller, the controller further being configured to control the rotational speed of the roller motor.
9. The system for controlling the areal density of the battery plate of claim 8, wherein the system further comprises an unwind roller, a wind-up roller, and a substrate for coating the slurry, the substrate being wound between the unwind roller and the wind-up roller, the wind-up roller motor rotating the wind-up roller and the unwind roller to control the speed of travel of the substrate.
10. A coater comprising the system for controlling the areal density of a battery pole piece according to any one of claims 1 to 9.
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CN202022127274.0U CN213727533U (en) | 2020-09-25 | 2020-09-25 | Control system and coating machine for surface density of battery pole piece |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN115569814A (en) * | 2022-10-26 | 2023-01-06 | 深圳市曼恩斯特科技股份有限公司 | Coating device and coating surface density closed-loop adjusting method thereof |
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2020
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
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CN115569814A (en) * | 2022-10-26 | 2023-01-06 | 深圳市曼恩斯特科技股份有限公司 | Coating device and coating surface density closed-loop adjusting method thereof |
CN115569814B (en) * | 2022-10-26 | 2023-12-26 | 深圳市曼恩斯特科技股份有限公司 | Coating device and coating surface density closed-loop adjusting method thereof |
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Effective date of registration: 20211229 Address after: 518116 Baolong Industrial Road, Baolong Industrial Park, Longgang District, Shenzhen, Guangdong, 3001, No. 3001 Patentee after: SHENZHEN BYD AUTO R&D Co.,Ltd. Address before: 518118 BYD Road, Pingshan New District, Shenzhen, Guangdong 3009 Patentee before: BYD Co.,Ltd. |
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