Lithium battery slurry demagnetizing system

Abstract

The utility model provides a lithium battery slurry demagnetizing system, which is used for preparing a battery active material and comprises a demagnetizing device, a demagnetizing device and a demagnetizing device, a coating device; and the slurry can remove magnetic substances through the demagnetizing device, and reaches the coating device through the magnetic substance detection device. By adopting the technical scheme, on one hand, the content of the magnetic substances in the slurry passing through the demagnetizing device can be detected on line in real time, and the information of the content of the magnetic substances in the slurry can be fed back in time, so that the production process can be adjusted in real time, and unqualified slurry is prevented from entering the next process (such as a coating device). And on the other hand, the content of the magnetic substances in all the slurry can be detected without manual sampling in the detection process, so that the production cost and the labor cost are reduced, the waste of the slurry is avoided, the detection reliability is improved, and the detection result can truly reflect the content of the magnetic substances in the slurry.

Description

Technical Field

[0001] This utility model belongs to the field of lithium battery slurry technology, specifically relating to a lithium battery slurry demagnetization system. Background Technology

[0002] Lithium-ion batteries include steel-cased, aluminum-cased, and plastic-cased batteries. Due to their advantages such as lighter weight, thinner structure, longer cycle life, better safety performance, higher energy density, stable discharge platform, excellent power performance, and environmental friendliness, lithium-ion batteries are widely used in electric bicycles, electric motorcycles, electric cars, power tools, electric toys, solar photovoltaic power generation systems, wind power generation systems, mobile communication base stations, backup UPS power supplies for large servers, emergency lighting, portable power supplies, and mining safety equipment, among other fields.

[0003] In the lithium battery production process, the slurry preparation process is particularly crucial. The slurry used in this process is for preparing battery active materials, and the content of magnetic substances in the slurry directly affects the discharge performance and cycle performance of the lithium battery. Specifically, if the magnetic substances in the slurry exceed the standard, it may cause an internal short circuit in the battery, leading to overheating, fire, or even explosion. Therefore, the content of magnetic substances in the slurry needs to be strictly controlled during lithium battery manufacturing.

[0004] In existing technologies, the control of magnetic materials in the lithium battery slurry preparation stage mainly relies on sampling inspection. This method requires manual sampling followed by testing with specific instruments to determine the magnetic content of the batch of slurry. This method has several drawbacks. First, sampling and testing inevitably waste some slurry. Second, the slurry requires manual sampling and periodic manual testing, thus wasting manpower. Third, the sampling method cannot achieve continuous monitoring; the sampled slurry is random, which may lead to large errors in the test results, making them unreliable. For example, even if the magnetic material content in the sampled slurry is within the standard, it cannot guarantee that the magnetic material content in the remaining unsampled slurry is within the standard. Fourth, the entire sampling and testing process requires waiting for the test results before proceeding to the next step, such as the coating process, which wastes time. Utility Model Content

[0005] The present invention provides the following technical solutions to solve the above-mentioned technical problems.

[0006] This invention provides a lithium battery slurry demagnetization system, wherein the slurry is a slurry used for preparing battery active materials, and the system includes:

[0007] Demagnetizing device, used to remove magnetic substances from slurry;

[0008] A coating apparatus, including a current collector, is used to coat a slurry, after removing magnetic materials, onto the current collector to form an electrode for a lithium battery.

[0009] The magnetic material detection device is located between the demagnetizing device and the coating device along the flow path of the slurry. The magnetic material detection device is connected to both the demagnetizing device and the coating device. The magnetic material detection device is used to detect the magnetic material content in the slurry after passing through the demagnetizing device.

[0010] The slurry can be demagnetized by a demagnetizing device and then pass through a magnetic material detection device before reaching the coating device.

[0011] By adopting the above technical solution, on the one hand, the content of magnetic materials in the slurry after passing through the demagnetization device can be detected online in real time, and the information on the content of magnetic materials in the slurry can be fed back in a timely manner, allowing the production process to be adjusted in real time and preventing unqualified slurry from entering the next process (such as the coating device). On the other hand, the above detection process can detect the content of magnetic materials in all slurries without manual sampling, reducing production and labor costs, avoiding slurry waste, improving the reliability of detection, and the detection results can accurately reflect the content of magnetic materials in the slurry.

[0012] Optionally, the magnetic material detection device includes:

[0013] The testing pipeline is connected at both ends to a demagnetizing device and a coating device, respectively.

[0014] An induction coil is wound around the outer wall of the detection pipe, and a current flows through the induction coil.

[0015] The detector can detect changes in the current in the induction coil and determine the content of magnetic materials in the slurry based on the changes in current.

[0016] Optionally, the magnetic material detection device also includes:

[0017] A signal amplifier, connected to both ends of the induction coil, is used to supply current to the induction coil and amplify the signal of current change in the induction coil.

[0018] Optionally, the outer peripheral wall of the detection pipe is provided with multiple positioning grooves, which are distributed along the axial direction of the detection pipe. The induction coil is located in the positioning groove, and the positioning groove is used to position the induction coil.

[0019] Optionally, the spacing between adjacent positioning slots along the axial direction is the same.

[0020] Optionally, the spacing between adjacent positioning slots along the axial direction is 3-5 mm.

[0021] Optionally, the test pipe can be made of ceramic or polytetrafluoroethylene.

[0022] Optionally, the lithium battery slurry demagnetization system also includes:

[0023] An automatic valve is located between the magnetic material detection device and the coating device along the flow path of the slurry. The automatic valve controls the connection and disconnection of the magnetic material detection device and the coating device.

[0024] The control unit connects to the automatic valve. The control unit controls the automatic valve to close when the content of magnetic material in the detected slurry exceeds the first qualified magnetic material content threshold, thereby interrupting the magnetic material detection device and the coating device.

[0025] Optionally, the lithium battery slurry demagnetization system also includes:

[0026] The early warning unit is used to issue an early warning signal when the content of magnetic material in the detected slurry exceeds the second qualified magnetic material content threshold, wherein the second qualified magnetic material content threshold is 80% to 90% of the first qualified magnetic material content threshold.

[0027] Optionally, the demagnetizing device includes a first demagnetizing unit and a second demagnetizing unit, which can be used independently to remove magnetic materials from the slurry. The lithium battery slurry demagnetizing system also includes:

[0028] A three-way valve is connected to a control unit, which controls the opening and closing of the three-way valve. The three ports of the three-way valve are respectively connected to the first demagnetizing unit, the second demagnetizing unit, and the magnetic material detection device.

[0029] The control unit controls the three-way valve to connect the first demagnetizing unit to the magnetic material detection device and disconnect the second demagnetizing unit from the magnetic material detection device. When the content of magnetic material in the detected slurry exceeds the second qualified magnetic material content threshold, the control unit controls the three-way valve to disconnect the first demagnetizing unit from the magnetic material detection device and connect the second demagnetizing unit to the magnetic material detection device. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of a lithium battery slurry demagnetization system according to an embodiment of the present invention;

[0031] Figure 2 This diagram shows the connection structure of the lithium battery slurry demagnetization system and the storage system in one embodiment of the present invention.

[0032] Figure 3 This is a schematic diagram of the overall structure of a magnetic material detection device according to an embodiment of the present invention;

[0033] Figure 4 This is a schematic diagram of the overall structure of the detection pipe and induction coil in one embodiment of the present invention;

[0034] Figure 5This diagram illustrates the content of magnetic substances in the slurry being tested, as detected by a magnetic substance detection device.

[0035] (Symbol Explanation)

[0036] 1-Lithium battery slurry demagnetization system, 2-Demagnetization device, 3-Magnetic material detection device, 4-Coating device, 5-Detection pipeline, 6-Induction coil, 7-Signal amplifier, 8-Server, 9-Display, 10-Feeding station, 11-Buffer station. Detailed Implementation

[0037] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. Although the description of this utility model will be presented in conjunction with preferred embodiments, this does not mean that the features of this utility model are limited to this embodiment. On the contrary, the purpose of describing the utility model in conjunction with the embodiments is to cover other options or modifications that may be derived based on the claims of this utility model. To provide a deep understanding of this utility model, many specific details will be included in the following description. This utility model may also be implemented without using these details. Furthermore, to avoid confusion or obscuring the focus of this utility model, some specific details will be omitted in the description. It should be noted that, without conflict, the embodiments and features in the embodiments of this utility model can be combined with each other.

[0038] Unless otherwise explicitly specified and limited, the terms "set up," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0039] The terms “first”, “second”, etc., are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0040] It should be noted that in this specification, similar reference numerals and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0041] To make the objectives, technical solutions, and advantages of this utility model clearer, the embodiments of this utility model will be described in further detail below with reference to the accompanying drawings.

[0042] like Figure 1As shown, this utility model provides a lithium battery slurry demagnetization system 1. The slurry is used for preparing battery active materials. The system 1 includes a demagnetization device 2, a coating device 4, and a magnetic material detection device 3. The demagnetization device 2 is used to remove magnetic materials from the slurry. The coating device 4 includes a current collector, which is used to coat the slurry with the magnetic materials removed onto the current collector to form the electrode of the lithium battery. The magnetic material detection device 3 is used to detect the content of magnetic materials in the slurry after passing through the demagnetization device 2. The magnetic material detection device 3 is located along the flow path of the slurry (e.g., along the flow path of the slurry). Figure 1 and Figure 2 The slurry (located in the Y direction) is between the demagnetizing device 2 and the coating device 4, and the magnetic material detection device 3 is connected to both the demagnetizing device 2 and the coating device 4. The slurry can pass through the demagnetizing device 2 to remove magnetic materials and then through the magnetic material detection device 3 to reach the coating device 4.

[0043] By adopting the above technical solution, on the one hand, the content of magnetic materials in the slurry after passing through the demagnetizing device 2 can be detected online in real time, and the information on the content of magnetic materials in the slurry can be fed back in a timely manner, so that the production process can be adjusted in real time to prevent unqualified slurry from entering the next process (such as the coating device 4). On the other hand, the above detection process can detect the content of magnetic materials in all slurries without manual sampling, which reduces production costs and labor costs, avoids slurry waste, improves the reliability of detection, and the detection results can accurately reflect the content of magnetic materials in the slurry.

[0044] Furthermore, such as Figures 2-4 As shown, in the above embodiment, the magnetic material detection device 3 includes a detection pipe 5, an induction coil 6, and a detector. The two ends of the detection pipe 5 are connected to the demagnetizing device 2 and the coating device 4, respectively. The induction coil 6 is wound around the outer peripheral wall of the detection pipe 5, and a current flows through the induction coil 6.

[0045] Based on the magnetic effect of electric current, a magnetic field is generated around induction coil 6 when current passes through it. When slurry passes through detection pipe 5, if the slurry contains magnetic materials, these materials will cut through the magnetic field generated by induction coil 6. According to Faraday's law of electromagnetic induction, this induces an electromotive force in induction coil 6, causing a change in current. The detector can detect this change in current in induction coil 6 and determine the content of magnetic materials in the slurry based on this change. This allows for accurate detection of magnetic materials in the slurry.

[0046] Furthermore, such as Figure 3As shown in the above embodiment, the magnetic material detection device 3 further includes a signal amplifier 7. It is connected to both ends of the induction coil 6. The signal amplifier 7 can both supply current to the induction coil 6 and amplify the current change signal in the induction coil 6. When magnetic material in the slurry passes through the magnetic field of the induction coil 6, it causes a slight change in the current in the induction coil 6. The lower the content of magnetic material in the slurry, the smaller the current change caused when passing through the detection pipe 5. The signal amplifier 7 can amplify these slight changes, so that even if the content of magnetic material in the slurry is low, the detector can accurately and sensitively detect the content of magnetic material in the slurry.

[0047] Furthermore, in the above embodiment, the outer peripheral wall of the detection pipe 5 is provided with a plurality of positioning grooves, which are respectively along the axial direction of the detection pipe 5 (e.g., Figure 3 and Figure 4 The induction coil 6 is distributed in the X direction (within the detection pipe 5), and is located in the positioning groove. The positioning groove is used to position the induction coil 6. This arrangement ensures that the induction coil 6 is always fixed on the detection pipe 5, preventing the induction coil 6 from shifting during operation, thereby ensuring the accuracy of the detection structure. In addition, by placing the induction coil 6 in the positioning groove, the installation of the induction coil 6 also becomes simpler and faster.

[0048] Furthermore, in the above embodiment, the spacing between adjacent positioning slots along the axial X direction is the same. This arrangement allows the induction coils 6 to be evenly distributed on the outer peripheral wall of the detection pipe 5, thereby further improving the accuracy of the detection.

[0049] Furthermore, such as Figure 4 As shown, in the above embodiment, the spacing between adjacent positioning slots along the axial direction X is 3-5mm, that is, the spacing d between adjacent induction coils 6 along the axial direction is 3-5mm.

[0050] Traditional slurry conveying pipes are made of stainless steel or other conventional metals, which are often magnetic. If the detection pipe 3, to which the induction coil 6 is wound, were also made of stainless steel or other metals, it might shield the magnetic field generated by the induction coil 6, thus affecting the accuracy of the detection. Therefore, the detection pipe 5 in this invention is made of a non-metallic material. This avoids the magnetic shielding effect, ensuring that the magnetic field can effectively act on the magnetic substances in the slurry, thereby accurately reflecting the content of magnetic substances in the slurry based on changes in current.

[0051] Specifically, the material of the testing pipe 5 is ceramic or polytetrafluoroethylene (PTFE). Both ceramic and PTFE have high smoothness, which helps the slurry flow smoothly in the pipe, reducing friction and resistance. In addition, both ceramic and PTFE have good corrosion resistance and wear resistance, which can resist the corrosion of chemicals in the slurry, resist the wear of hard particles that may be contained in the slurry on the inner wall of the testing pipe 5, extend the service life of the testing pipe 5, and maintain the structural integrity of the testing pipe 5.

[0052] Furthermore, in the above embodiment, the lithium battery slurry demagnetization system 1 also includes a control unit and an automatic valve (the automatic valve is connected to the control unit). The automatic valve is located between the magnetic material detection device 3 and the coating device 4 along the slurry flow path Y, and controls the connection and disconnection of the magnetic material detection device 3 and the coating device 4. When the magnetic material content in the detected slurry exceeds the first qualified magnetic material content threshold, the control unit controls the automatic valve to close, thereby interrupting the connection between the magnetic material detection device 3 and the coating device 4. This prevents unqualified slurry from flowing into the coating device 4, thus ensuring the quality of the slurry. Slurry exceeding the first qualified magnetic material content threshold is considered unqualified slurry. When the slurry passing through the online magnetic material detection device 4 is detected as unqualified, that is, the magnetic content exceeds the first qualified magnetic material content threshold, if the automatic valve is not closed to interrupt the connection between the magnetic material detection device 3 and the coating device 4, the unqualified slurry will enter the coating device 4 for coating. This excessive magnetic material may cause a short circuit inside the battery, thereby causing a safety hazard.

[0053] Furthermore, the lithium battery slurry demagnetization system 1 also includes an early warning unit. The early warning unit issues an early warning signal when the detected magnetic material content in the slurry exceeds a second acceptable magnetic material content threshold. This second acceptable magnetic material content threshold is 80% to 90% of the first acceptable magnetic material content threshold. By setting a lower threshold (the second acceptable magnetic material content threshold), an early warning signal can be issued as soon as the magnetic material content begins to deviate from the normal range. This gives operators more time to investigate the cause and take corrective measures (e.g., inspecting the demagnetization device 2, replacing or cleaning the magnetic rods in the demagnetization device 2). In other words, when an early warning signal is issued, the slurry is still acceptable, the slurry flow path is not interrupted, and the slurry after passing through the magnetic material detection device 3 will still enter the coating device 4 for coating. Because the early warning unit issues a warning before the magnetic material content reaches a higher threshold (the first acceptable magnetic material content threshold), it can prevent the magnetic material content from exceeding the standard, thereby avoiding the production of unqualified battery products.

[0054] Specifically, refer to Figure 5 and combined Figure 3A represents the magnetic substance content in the substandard slurry, which is also the first acceptable magnetic substance content threshold. B serves as the warning line for the magnetic content of the slurry, which is also the second acceptable magnetic substance content threshold. The second acceptable magnetic substance content threshold can be set according to the actual site conditions. Specifically, the second acceptable magnetic substance content threshold is 80% to 90% of the first acceptable magnetic substance content threshold. Figure 5 The curve in the figure represents the content of magnetic substances detected in the slurry as it passes through the detection pipe 5. The content of magnetic substances in the slurry is determined based on the change in current (when the slurry flows through the detection pipe 5, the magnetic substances in the slurry cut the magnetic field generated by the induction coil 6, thereby causing a change in current, and the content of magnetic substances in the slurry is then determined based on this change in current).

[0055] The demagnetizing device 2 can remove some magnetic impurities. However, due to differences in the magnetic content of the raw materials and the varying usage time of the demagnetizing device 2, the demagnetizing effect varies. Therefore, it is necessary to test the content of magnetic substances in the slurry after passing through the demagnetizing device 2. The above-mentioned technical solution can not only detect changes in the magnetic substances in the slurry in real time and monitor the content of magnetic substances, but also provide an early warning function, giving timely alerts so that production personnel can clean the magnetic rods in time and ensure the quality of the slurry.

[0056] Furthermore, combined Figure 2 The demagnetizing device 2 includes a first demagnetizing unit and a second demagnetizing unit, which can be used independently to remove magnetic materials from the slurry. The lithium battery slurry demagnetizing system 1 also includes a three-way valve. The three-way valve is connected to a control unit, which can control the opening and closing of the three-way valve.

[0057] The three ports of the three-way valve are connected to the first demagnetizing unit, the second demagnetizing unit, and the magnetic material detection device 3, respectively. The control unit controls the three-way valve to connect the first demagnetizing unit to the magnetic material detection device and disconnect the second demagnetizing unit from the magnetic material detection device. That is, the slurry in the storage system (which feeds slurry into the buffer station 11 through the feeding station 10) is demagnetized by the first demagnetizing unit, and then tested by the magnetic material detection device. Slurry that passes the magnetic material content test will then reach the coating device 3 for coating to complete the preparation of the lithium battery electrode.

[0058] When the content of magnetic material in the tested slurry exceeds the second qualified magnetic material content threshold, the control unit controls the three-way valve to disconnect the first demagnetizing unit from the magnetic material detection device and connect the second demagnetizing unit to the magnetic material detection device. Since the slurry with the second qualified magnetic material content is still considered qualified, the three-way valve can be controlled to disconnect the first demagnetizing unit from the magnetic material detection device 3 and connect the second demagnetizing unit to the magnetic material detection device 3. This allows the second demagnetizing unit to continue demagnetizing the slurry, which then passes through the magnetic material detection device 3 for detection and the coating device 4 for coating to complete the preparation of the lithium battery electrode. During this period, the first demagnetizing unit can be inspected, for example, to check whether the magnetic rod in the demagnetizing device has reached the end of its service life or whether the magnetic rod has absorbed too many impurities, thus reducing the demagnetizing effect. The magnetic rod can then be replaced or cleaned. This allows for more effective control of the magnetic material content in the slurry, for example, controlling the magnetic material content below the second qualified magnetic material content threshold B, thereby ensuring the quality and safety of the lithium battery product.

[0059] Although the present invention has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the present invention in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of the present invention to these descriptions. Those skilled in the art can make various changes in form and detail, including some simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A lithium battery slurry demagnetization system, wherein the slurry is a slurry for preparing battery active materials, characterized in that, include: A demagnetizing device is used to remove magnetic substances from the slurry; A coating apparatus, including a current collector, is used to coat a slurry, after removing magnetic materials, onto the current collector to form an electrode of the lithium battery; A magnetic material detection device is located between the demagnetizing device and the coating device along the flow path of the slurry. The magnetic material detection device is connected to both the demagnetizing device and the coating device. The magnetic material detection device is used to detect the content of magnetic materials in the slurry after passing through the demagnetizing device. The slurry can have magnetic substances removed by the demagnetizing device and then reach the coating device after passing through the magnetic substance detection device.

2. The lithium battery slurry demagnetization system according to claim 1, characterized in that, The magnetic material detection device includes: The detection pipe has two ends connected to the demagnetizing device and the coating device, respectively. An induction coil is wound around the outer peripheral wall of the detection pipe, and a current flows through the induction coil. The detector is capable of detecting changes in the current in the induction coil and determining the content of magnetic materials in the slurry based on the changes in current.

3. The lithium battery slurry demagnetization system according to claim 2, characterized in that, The magnetic material detection device also includes: A signal amplifier, connected to both ends of the induction coil, is used to provide the current to the induction coil and amplify the signal of the change in current in the induction coil.

4. The lithium battery slurry demagnetization system according to claim 2, characterized in that, The outer peripheral wall of the detection pipe is provided with multiple positioning grooves, which are distributed along the axial direction of the detection pipe. The induction coil is located in the positioning groove, and the positioning groove is used to position the induction coil.

5. The lithium battery slurry demagnetization system according to claim 4, characterized in that, The spacing between adjacent positioning slots along the axial direction is the same.

6. The lithium battery slurry demagnetization system according to claim 5, characterized in that, The spacing between adjacent positioning grooves along the axial direction is 3-5 mm.

7. The lithium battery slurry demagnetization system according to claim 2, characterized in that, The detection pipe is made of ceramic or polytetrafluoroethylene.

8. The lithium battery slurry demagnetization system according to claim 1, characterized in that, The lithium battery slurry demagnetization system also includes: An automatic valve is located between the magnetic material detection device and the coating device along the flow path of the slurry; the automatic valve controls the connection and disconnection of the magnetic material detection device and the coating device. A control unit is provided, wherein the automatic valve is connected to the control unit, and the control unit is used to control the automatic valve to close so as to interrupt the magnetic material detection device and the coating device when the content of magnetic material in the detected slurry exceeds a first qualified magnetic material content threshold.

9. The lithium battery slurry demagnetization system according to claim 8, characterized in that, The lithium battery slurry demagnetization system also includes: The early warning unit is used to issue an early warning signal when the content of magnetic material in the detected slurry exceeds the second qualified magnetic material content threshold, wherein the second qualified magnetic material content threshold is 80% to 90% of the first qualified magnetic material content threshold.

10. The lithium battery slurry demagnetization system according to claim 9, characterized in that, The demagnetizing device includes a first demagnetizing unit and a second demagnetizing unit, which can be used independently to remove magnetic substances from the slurry. The lithium battery slurry demagnetizing system further includes: A three-way valve is connected to the control unit, which controls the opening and closing of the three-way valve. The three ports of the three-way valve are respectively connected to the first demagnetizing unit, the second demagnetizing unit, and the magnetic material detection device. The control unit is used to control the three-way valve to connect the first demagnetizing unit to the magnetic material detection device and disconnect the second demagnetizing unit from the magnetic material detection device. When the content of magnetic material in the detected slurry exceeds the second qualified magnetic material content threshold, the control unit controls the three-way valve to disconnect the first demagnetizing unit from the magnetic material detection device and connect the second demagnetizing unit to the magnetic material detection device.

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