Battery pole piece dewatering system and battery pole piece dewatering method

Abstract

The present invention relates to a battery pole piece dehydration system and a battery pole piece dehydration method. The battery pole piece dehydration system comprises a sequentially arranged unwinding mechanism, an oven for the battery pole piece to pass through, and a reeling mechanism, an online sampling and testing assembly is arranged between the oven and the reeling mechanism, and the online sampling and testing assembly comprises: a pole piece sampling device for online cutting of pole piece samples; and a moisture testing device, the position of the moisture testing device is arranged to receive the pole piece samples cut by the pole piece sampling device and test the moisture in the received pole piece samples. In the battery pole piece dehydration method used in the battery pole piece dehydration system, during the operation of the battery pole piece dehydration system, the battery pole piece is subjected to online sampling and testing by the online sampling and testing assembly. The battery pole piece dehydration system and the battery pole piece dehydration method advantageously prevent unqualified pole pieces from entering subsequent processes, thereby reducing the probability of failure.

Description

Technical Field

[0001] The present invention relates to the field of pole piece manufacturing; specifically, the present invention relates to a battery pole piece dehydration system and a battery pole piece dehydration method. Background Art

[0002] Lithium-ion battery electrodes are the key components of lithium-ion batteries.

[0003] During the preparation of lithium-ion battery electrodes, a liquid slurry consisting of positive and negative electrode micro-nano particle materials, adhesives, and solvents is evenly coated on the surface of the current collector copper foil and aluminum foil to form a layer of solvent-containing wet coating. Then, in the battery electrode dehydration system, hot air is used to blow the surface of the wet coating, so that the coating surface and the hot air conduct convection heat exchange, and the convection heat exchange causes the solvent of the wet coating to evaporate by heat to remove the moisture in the wet coating, thereby achieving the purpose of drying the wet coating.

[0004] The battery pole piece dewatering system usually includes an unwinding mechanism, an oven, and a rewinding mechanism. After the pole piece is unwound, it passes through a high-temperature oven at high speed, and the hot air takes away the moisture in the pole piece, and then it is rewound at the tail. Generally speaking, in the subsequent process, manual sampling will be performed at the tail of the pole piece to test the water content of the pole piece.

[0005] If the water content of the electrode exceeds the standard after water removal, it will lead to abnormalities such as deterioration of battery performance, rapid decay of cycle life, increase in internal resistance, and eventually failure of the battery. Moreover, once the electrode with excessive water content is made into a battery and reaches the customer, it is difficult to identify this defect and there is no way to rework it. The only option is to wait for the battery to fail and then scrap it, resulting in a waste of raw materials.

[0006] Therefore, it is extremely important to control the water content of the electrode after dehydration in battery cell production. It is necessary to prevent unqualified electrodes from entering subsequent processes to reduce the probability of failure. Summary of the invention

[0007] In view of this, the present invention provides a battery pole piece dehydration system and a battery pole piece dehydration method, thereby solving or at least alleviating one or more of the above-mentioned technical problems and other problems existing in the prior art.

[0008] First, according to one aspect of the present invention, a battery pole piece dehydration system is provided, wherein the battery pole piece dehydration system comprises a sequentially arranged unwinding mechanism, an oven for the battery pole piece to pass through, and a rewinding mechanism, and an online sampling test assembly is arranged between the oven and the rewinding mechanism, and the online sampling test assembly comprises: a pole piece sampling device for cutting pole piece samples online; and a moisture testing device, the position of the moisture testing device is set to receive the pole piece samples cut by the pole piece sampling device and test the moisture in the received pole piece samples. Through the online sampling test of the online sampling test assembly, the water content at different positions of the pole piece roll can be obtained, and these positions will correspond to different layers of the inner and outer circles of the pole piece roll after rewinding, so it is conducive to monitoring the water content change of the entire roll, and can effectively solve the problem of pole pieces with unqualified water content flowing into the next process, reducing the probability of failure.

[0009] Optionally, in the battery pole piece dehydration system as described above, a correction roller is arranged between the oven and the winding mechanism, and the online sampling test assembly is arranged upstream of the correction roller. Affected by the traction force, the pole piece has a greater tension at the winding roller close to the winding mechanism. Placing the online sampling test assembly upstream of the correction roller is conducive to reducing the risk of breaking the pole piece during sampling.

[0010] Optionally, in the battery pole piece dehydration system as described above, the battery pole piece dehydration system further comprises: a control module; and a marking device located between the oven and the winding mechanism, wherein the control module receives the test results of the moisture testing device in real time and identifies unqualified battery pole piece parts according to the test results, and when unqualified battery pole piece parts are identified, the control module instructs the marking device to mark the unqualified battery pole piece parts. By providing a marking device to automatically mark unqualified products, the reliability is higher and the marking quality consistency is better than manual marking.

[0011] Optionally, in the battery pole piece dewatering system as described above, the pole piece sampling device is located on the upper side of the battery pole piece conveying path, the moisture testing device is located on the lower side of the battery pole piece conveying path, and the positions of the pole piece sampling device and the moisture testing device are arranged so that the pole piece sample cut by the pole piece sampling device can fall into the moisture testing device by gravity and / or a slide. Such an arrangement can reliably ensure that the pole piece sample enters the moisture testing device to complete the water content test.

[0012] Optionally, in the battery pole piece dehydration system as described above, the battery pole piece dehydration system further has an openable sealing cover, the winding mechanism and the online sampling and testing assembly are both located in the sealing cover, and the sealing cover is sealedly connected to the oven at the outlet end of the oven. The sealed connection between the sealing cover and the oven can effectively provide a low-humidity environment for the pole piece sampling test and winding process, prevent the moisture of the external environment from entering between the sealing cover and the oven and adversely affecting the process, and avoid the pole piece from rapidly absorbing moisture during the cooling process after leaving the oven, resulting in excessive water content in the pole piece.

[0013] Optionally, in the battery pole piece dehumidification system as described above, a desiccant is placed in the sealing cover, or an air inlet for blowing dry gas into the sealing cover is provided at the sealing cover. Both the desiccant and the dry gas can help to further improve the low temperature environment in the sealing cover.

[0014] Optionally, in the battery pole piece dewatering system as described above, the sealing cover has a transparent observation window. The provision of the observation window enables the staff to observe the sampling and testing process inside the sealing cover during inspection.

[0015] Optionally, in the battery pole piece dehydration system as described above, the pole piece sampling device is a laser cutting machine, a mechanical cutting machine or an ultrasonic cutting machine.

[0016] Optionally, in the battery pole piece dehydration system as described above, the sampling position of the pole piece sampling device is located at the edge of the coating area of ​​the battery pole piece.

[0017] Optionally, in the battery pole piece dehydration system as described above, the pole piece sampling device cuts pole piece samples on the battery pole piece at a fixed sampling frequency, or, the pole piece sampling device cuts pole piece samples on the battery pole piece at a variable sampling frequency according to the stability of the battery pole piece dehydration system.

[0018] Secondly, according to another aspect of the present invention, there is provided a battery pole piece dehydration method for a battery pole piece dehydration system as described in any one of the aforementioned aspects, wherein, during the operation of the battery pole piece dehydration system, the battery pole piece is subjected to online sampling and testing by the online sampling and testing assembly.

[0019] Optionally, in the battery pole piece dehydration method as described above, the battery pole piece dehydration method further comprises the following step: when it is detected that the water content of the pole piece sample exceeds the standard, unqualified products are marked manually by staff or automatically by marking equipment.

[0020] Optionally, in the battery pole piece dehydration method as described above, the battery pole piece dehydration system further has an openable sealing cover, the winding mechanism and the online sampling and testing assembly are both located in the sealing cover, and the sealing cover is sealedly connected to the oven at the outlet end of the oven, wherein, during the process of dehydrating the battery pole piece, the sealing cover is always kept closed. During the process of dehydrating the battery pole piece, the sealing cover is always kept closed, which can effectively maintain the low temperature environment in the sealing cover.

[0021] Optionally, in the above-mentioned battery pole piece dehydration method, a desiccant is placed in the sealing cover, or a dry gas is continuously blown into the sealing cover during the closing of the sealing cover. Both the desiccant and the dry gas can help to further improve the low temperature environment in the sealing cover.

[0022] From the following detailed description in combination with the accompanying drawings, the principles, characteristics, features and advantages of the various technical solutions according to the present invention can be clearly understood. The solution of the present invention can overcome or at least alleviate the defects or deficiencies in the existing battery pole piece dehydration system or battery pole piece dehydration method, and can especially prevent unqualified battery pole pieces from entering the subsequent processes of battery pole pieces and batteries, thereby reducing the probability of failure. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] With reference to the accompanying drawings, other features and advantages of the present invention will become more apparent through the following detailed description of exemplary embodiments of the present invention; however, it should be understood that the accompanying drawings are only for illustrative purposes and do not limit the scope of the present invention.

[0024] Figure 1 A battery pole piece dewatering system according to an embodiment of the present invention is schematically shown.

[0025] Reference numerals:

[0026] 1-unwinding mechanism; 2-drying oven; 3-rewinding mechanism; 4-battery pole piece; 5-first deviation correction roller; 6-second deviation correction roller; 7-third deviation correction roller; 8-online sampling test assembly; 81-pole piece sampling device; 82-moisture testing device; 9-sealing cover; 10-vent. DETAILED DESCRIPTION

[0027] The exemplary embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. The various components and structures in the accompanying drawings are only schematic and are not necessarily drawn to scale. It should be understood that unless otherwise specifically stated, the relative arrangement of the components and steps, numerical expressions and numerical values, etc. described in these embodiments are only illustrative and are not intended to limit the scope of the present invention.

[0028] In this document, the terms “first” and “second” are only used for the purpose of distinguishing between the two but are not intended to indicate their order and relative importance.

[0029] In addition, for any single technical feature described or implied in the embodiments mentioned herein, or any single technical feature displayed or implied in the drawings, the present invention still allows any combination or addition or deletion between these technical features (or their equivalents) without any technical obstacles, so it should be considered that these more embodiments according to the present invention are within the scope of the description of this article. In addition, for the sake of brevity, general matters that are already known to those skilled in the art, such as the basic working principles of the coating process, baking process, and rolling process commonly used in the field of lithium battery manufacturing, are not described in detail in this article.

[0030] Figure 1 A battery pole piece dehydration system according to an embodiment of the present invention is schematically shown. The battery pole piece dehydration system can be applied to the baking process of battery pole piece production, which is between the coating process and the rolling process of battery pole piece production. In the coating process, a slurry coating is applied on a foil to form a pole piece. In the baking process, the pole piece is dehumidified in an oven to remove moisture from the coating. In the rolling process, the bonding strength between the coating and the foil is enhanced, while the porosity of the pole piece is reduced.

[0031] As can be seen from the figure, the battery pole piece dehumidification system of this embodiment of the present invention may include a sequentially arranged unwinding mechanism 1, an oven 2 for the battery pole piece 4 to pass through, and a rewinding mechanism 3. The battery pole piece dehumidification system may be entirely located in a drying chamber, or at least the oven 2 and the rewinding mechanism 3 may be located in a drying chamber, so as to locally control its low humidity environment.

[0032] The unwinding mechanism 1 is arranged upstream of the oven 2. The pole piece material roll transferred from the previous coating process is placed on the unwinding roller of the unwinding mechanism 1. The battery pole piece 4 released from the pole piece material roll at the unwinding mechanism 1 is pulled into the oven 2. In an optional embodiment, a correction roller may be provided between the unwinding mechanism 1 and the oven 2 to ensure the directional conveyance of the pole piece. Furthermore, in different embodiments, different numbers and arrangements of correction rollers may be used depending on the specific circumstances. In the figure, only a first correction roller 5 is shown here as an example.

[0033] The oven 2 is used to dry the battery pole pieces 4 conveyed therethrough. The heating channel in the oven 2 may be provided with a conveying device for carrying the battery pole pieces, such as but not limited to guide rollers. The oven 2 may also be provided with an exhaust device for exhausting moisture from the battery pole pieces 4 from the oven 2. In different embodiments, the interior of the oven 2 may have different specific structures and arrangements according to specific circumstances, which will not be described in detail here.

[0034] The winding mechanism 3 is arranged downstream of the oven 2, and is used to wind up the battery electrode 4 dried by the oven 2. After being dried in the oven 2, the battery electrode 4 is pulled toward the winding mechanism 3 and wound up at the winding roller of the winding mechanism 3. The wound electrode sheet coil can be used for subsequent rolling processes. In an optional embodiment, a deflection correction roller may be provided between the oven 2 and the winding mechanism 3 to ensure the directional conveying of the electrode. Furthermore, in different embodiments, different numbers and arrangements of deflection correction rollers may be used depending on the specific circumstances. In the figure, only two deflection correction rollers are shown here as an example, namely the second deflection correction roller 6 and the third deflection correction roller 7.

[0035] In the embodiment shown in the figure, an online sampling test assembly 8 is arranged between the oven 2 and the winding mechanism 3. For example, both can be fixed on a frame or a base of a battery electrode dewatering system.

[0036] By arranging the online sampling and testing assembly 8 between the oven 2 and the winding mechanism 3, during the operation of the battery pole piece dehydration system, the battery pole piece 4 dried in the oven 2 is sampled and tested for water content exceeding the standard before being wound up. If the water content does not exceed the standard, the battery pole piece dehydration system is allowed to carry out the baking process of unwinding, baking, and winding normally. Once it is tested that the water content of the pole piece exceeds the standard, it is marked on the pole piece, and it is cut off or reworked and re-baked before the next rolling process. At this time, the marking work can be done manually or automatically by the equipment.

[0037] Here, by sampling the battery pole piece 4 online and then testing it, the water content of different positions of the pole piece in the pole piece roll can be tested, which can basically represent the water content of the entire roll. Specifically, it can not only measure the water content of the outer layer of the roll, but also measure the water content of the inner layer of the roll, which is beneficial to monitor the change of the water content of the entire pole piece roll. In different embodiments, in order to achieve different test accuracies, the frequency of sampling tests can be controlled as needed. The higher the frequency of sampling tests, the higher the test accuracy can be obtained, and the more conducive it is to reduce the probability of pole pieces with unqualified water content entering subsequent processes. Especially when the water content of the incoming pole piece is inconsistent, the temperature control fails during baking, etc., resulting in inconsistent water content at different positions of the pole piece after baking, this online sampling test reflects a more significant technical effect.

[0038] Compared with the situation of only testing the water content at the end of the coil after the drying process, it greatly improves the quality of the coil after the baking process. Because the water content tested at the end of the coil cannot truly represent the water content of the inner layer of the coil, which may cause waste. In addition, the tail of the coil may absorb water again after leaving the oven and winding, so the water content measured only at this part may not be accurate and cannot represent the water content of the electrodes in other parts of the entire coil.

[0039] In addition, by sampling and testing the battery pole pieces 4 online, compared with directly testing the pole pieces in transit, it not only does not affect the normal production efficiency of the pole pieces, but also achieves more reliable test results, which can achieve very beneficial technical effects.

[0040] In the illustrated embodiment, the online sampling and testing assembly 8 is arranged after the oven 2 and between the deflection correction roller and the winding mechanism 3, that is, downstream of the deflection correction roller and upstream of the winding mechanism 3. In this arrangement, the water content of the pole piece sample tested by the online sampling and testing assembly 8 is closer to the water content of the pole piece at each layer and each position in the roll.

[0041] In an optional embodiment, the online sampling test assembly 8 may also be arranged between different deflection correction rollers, such as the second deflection correction roller 6 and the third deflection correction roller 7, or between the deflection correction roller and the oven 2. By arranging the online sampling test assembly 8 away from the winding roller of the winding mechanism 3, it is helpful to prevent the interference between the high-speed moving pole piece and the pole piece sampling from tearing the pole piece. Because the pole piece is pulled forward, the tension is greater at the position close to the winding roller. Once there is interference with the sampling process, the force will have the risk of tearing the pole piece apart.

[0042] from Figure 1 It can be seen that in this embodiment of the present invention, the online sampling and testing assembly 8 can include a pole piece sampling device 81 and a moisture testing device 82. The pole piece sampling device 81 can be used to cut pole piece samples online. Compared with manual sampling, this automatic sampling significantly improves the sampling efficiency. The moisture testing device 82 can be used to test the moisture in the received pole piece sample, and its position is set to receive the pole piece sample cut by the pole piece sampling device 81.

[0043] In the example shown in the figure, the electrode sampling device 81 is located on the upper side of the battery electrode conveying path, and the moisture testing device 82 is located on the lower side of the battery electrode conveying path. At the same time, the positions of the electrode sampling device 81 and the moisture testing device 82 are arranged so that the electrode sample cut by the electrode sampling device 81 can fall into the moisture testing device 82 through gravity and / or a slide (not shown).

[0044] For example, the electrode sampling device 81 can be arranged close to the battery electrode 4. The moisture testing device 82 can be located close to the position of the battery electrode 4 cut by the electrode sampling device 81, for example, below the cut position of the battery electrode 4. At the same time, considering the high-speed movement of the battery electrode 4, it can be located slightly below the cut position of the battery electrode 4. In addition, if the electrode sample falls far away, or considering the high-speed movement of the battery electrode 4, a slide rail can be provided to guide the electrode sample that falls after cutting, so that it can reliably fall into the moisture testing device 82, be received by the moisture testing device 82 and be tested therein.

[0045] In different specific embodiments, the pole piece sampling device 81 may have different implementation methods. For example, depending on the specific situation, the pole piece sampling device 81 may include but is not limited to a laser cutter, a mechanical cutter or an ultrasonic cutter. The principle of laser cutting includes using the energy released when the laser beam is irradiated to the surface of the workpiece to melt and evaporate the workpiece to achieve the purpose of cutting. The principle of mechanical cutting includes using a tool (such as but not limited to a stamping tool, etc.) to directly cut the workpiece. The principle of ultrasonic cutting includes cutting the workpiece through the vibration generated by an ultrasonic vibrator. Given the above cutting principle, a suitable cutting tool can be selected in different embodiments as needed. If necessary, in order to prevent the pole piece from being torn off during sampling, the pole piece sampling device can be moved accordingly with the pole piece during sampling.

[0046] In addition to the above-mentioned laser cutting machine, mechanical cutting machine and ultrasonic cutting machine, other suitable implementations of the pole piece sampling device 81 may also be desirable and will not be described in detail here.

[0047] The pole piece sample cut by the pole piece sampling device 81 may be in the shape of a disc. In other optional embodiments, the pole piece sample cut may also be in a square, a triangle or any other shape. Selecting a regular shape can facilitate calculation of the area of ​​the pole piece sample, thereby making it easier to calculate its weight, and to determine whether the moisture content therein meets the standard based on the weight.

[0048] In one embodiment of the battery pole piece dehydration system, the sampling position of the pole piece sampling device 81 can be located at the edge of the coating area of ​​the battery pole piece 4. Regarding the sampling position, the baking position in the oven 2 can be considered. During the baking process in the oven 2, the baking temperature of the middle position of the battery pole piece 4 is the highest, and the baking temperature at the two edge positions is relatively low. Therefore, the moisture content at the two edge positions of the battery pole piece is also relatively high. Therefore, taking the two outer edge areas of the battery pole piece as the standard, if these edge areas can meet the water content requirements, the water content requirements can also be met at the middle position. It should be noted that the present invention does not exclude the implementation method of the sampling position being located in the middle area of ​​the coating area of ​​the battery pole piece.

[0049] In one embodiment, the sampling frequency of the pole piece sampling device 81 can be a fixed sampling frequency. The fixed sampling step can be set according to specific needs. A denser sampling frequency will lead to a higher pole piece scrap rate; a sparser sampling frequency may lead to the risk of missed detection. In other embodiments, a non-fixed sampling frequency is also feasible. For example, a higher sampling frequency can be used when it can be expected that the battery pole piece dehydration system will work unstably, and a lower sampling frequency can be used when it can be expected that the battery pole piece dehydration system will work relatively stably.

[0050] In the illustrated embodiment, the moisture testing device 82 may be a measuring instrument for measuring water content using the Karl Fischer method. After the moisture testing device 82 receives the electrode sample, the electrode sample enters the container of the moisture testing device 82. At this time, the container is sealed, and then the electrode sample is heated at high temperature to release moisture from the electrode sample. The moisture vapor is carried to a beaker containing a flux (such as a Karl Fischer reagent) through an airflow, and an electrode capable of inducing an electrochemical potential reaction is inserted into the flux. When the moisture released from the electrode sample reacts with the melt in the flux, the moisture testing device 82 displays the water content based on the corresponding electrochemical potential difference. It should be noted that moisture testing devices based on different principles are also applicable; they will not be described in detail here.

[0051] The battery electrode dewatering system may further include a control module (not shown) and a marking device located between the oven 2 and the winding mechanism 3. The control module may receive the test results of the moisture testing device 8 in real time and identify unqualified battery electrode parts based on the test results. When an unqualified battery electrode part is identified, the control module may instruct the marking device to mark the unqualified battery electrode part. The specific marking method may include but is not limited to affixing a colored label, such as a yellow label, to the unqualified battery electrode part. In this way, these unqualified battery electrode parts can be identified in the subsequent rolling process, and they can be fed back to the process personnel, and the defective products can be selected separately and reworked and re-baked.

[0052] from Figure 1It can also be seen that a sealing cover 9 is also provided in the battery electrode dehydration system of the illustrated embodiment, and the second deviation correction roller 6, the third deviation correction roller 7, the online sampling test assembly 8 and the winding mechanism 3 after the oven 2 are all sealed in the sealing cover 9. In the case where the deviation correction roller is not provided, the winding mechanism 3, the online sampling test assembly 8, etc. can be arranged in the sealing cover 9. A desiccant can be provided in the sealing cover 9. Compared with the drying chamber mentioned above, the sealing cover 9 can reduce the dew point value of the electrode environment leaving the oven 2 by an order of magnitude. The sealing cover 9 can be opened to facilitate the removal of the electrode material coil wound up at the winding mechanism 3 and enter the next rolling process.

[0053] The sealing cover 9 is sealedly connected to the oven 2 at the discharge port end of the oven 2. For example, as shown in the figure, in addition to the discharge port position through which the battery pole piece 4 passes, another vent 10 can be provided at the discharge port end so that the sealing cover 9 is connected to the oven 2. According to different embodiments, the number, area, cross-sectional shape, etc. of the vent 10 may not be limited.

[0054] In addition, the sealed connection between the sealing cover 9 and the oven 2 can effectively provide a low-humidity environment for the electrode sampling test and winding process, prevent the moisture from the external environment from entering between the sealing cover 9 and the oven 2 and adversely affecting the process, and avoid the electrode from absorbing moisture quickly during the cooling process after leaving the oven 2, causing the water content of the electrode to increase again and exceed the standard, thereby reducing the baking efficiency. After the electrode is rolled into a electrode material roll, the inner circle of the electrode is not in direct contact with the air, which can significantly reduce the possibility of water absorption of the electrode.

[0055] In order to further improve the low humidity environment in the sealing cover 9, which is conducive to satisfying the cooling of the pole piece and preventing the risk of the pole piece absorbing moisture, in a further embodiment, an air inlet for blowing dry gas into the sealing cover 9 can be provided at the sealing cover 9. The position, number, area, cross-sectional shape, air intake direction, air intake strength, etc. of the air inlet can be set as needed, and will not be repeated here. The dry gas here can include but is not limited to dry air, nitrogen, etc.

[0056] The sealing cover 9 can be made of various materials, such as but not limited to plastic, metal, etc. In order to facilitate inspection and enable the staff to observe the operation inside the sealing cover 9, the sealing cover 9 can be made of transparent materials, such as transparent plastic, glass, etc. Alternatively, when the sealing cover 9 is made of opaque material, a transparent observation window can be provided for the sealing cover 9 to facilitate inspection needs.

[0057] Based on the above description, combined with the attached Figure 1It can be understood that the various embodiments of this battery pole piece dehydration system, by including, for example but not limited to, an online sampling test component 8, a sealing cover 9, etc., advantageously and significantly improve the dehydration performance of the battery pole piece dehydration system, prevent unqualified battery pole pieces from entering subsequent processes, and provide the possibility for high quality and high efficiency of battery pole pieces and subsequent battery processes.

[0058] In addition, the present invention also provides a method for removing water from a battery pole piece using the battery pole piece removal system as described in any of the above embodiments. In the embodiment of this method, an online sampling test assembly is used to perform an online sampling test on the battery pole piece.

[0059] Specifically, according to this method, after the battery electrode water removal system is started, the online sampling and testing component begins sampling and testing.

[0060] Specifically, the electrode sampling device 81 cuts electrode samples from the electrode passing through the oven 2. After the electrode samples fall into the moisture testing device 82, the moisture testing device 82 performs a moisture test on the electrode samples to detect the water content therein.

[0061] According to a specific embodiment, when the water content exceeds the standard, the unqualified products can be marked manually by the staff or by a marking device. The process can be that the staff or automatic equipment applies color marks to the unqualified products. These marks can be painted or affixed labels or marks.

[0062] After the sampling test of the whole roll of pole pieces is completed, the pole piece roll after dehydration is transferred away from the winding mechanism 3. In the subsequent rolling process, defective products can be selected according to the marks on the pole piece roll, and they can be reworked and sent back for re-baking.

[0063] In the case where the battery pole piece dehydration system has a sealing cover 9, in an optional embodiment of the battery pole piece dehydration method, the sealing cover 9 needs to be opened before the pole piece roll is transferred from the winding mechanism 3. In addition, during the dehydration process of the battery pole piece, the sealing cover 9 needs to be kept closed at all times, and the sealing cover 9 provided with an air inlet can continuously blow dry gas into the sealing cover 9.

[0064] Based on the above description, combined with the attached Figure 1 It can be understood that the various embodiments of the battery pole piece dehydration method can advantageously and significantly improve the dehydration performance of the battery pole piece dehydration system, prevent unqualified battery pole pieces from entering subsequent processes, and provide the possibility for high quality and high efficiency of battery pole pieces and subsequent battery processes and products.

[0065] The above exemplary embodiments of the battery pole piece dehydration system and the battery pole piece dehydration method according to the present invention are described. Without departing from the scope and spirit of the described embodiments, those skilled in the art can make additions, subtractions or modifications to the embodiments and the features therein. All equivalent technical solutions should belong to the scope of the present invention and are considered to fall within the scope of the present invention.

Claims

1. A battery pole piece dewatering system, characterized in that: The battery pole piece dewatering system comprises an unwinding mechanism (1), an oven (2) for the battery pole piece (4) to pass through, and a rewinding mechanism (3) arranged in sequence, and an online sampling test component (8) is arranged between the oven (2) and the rewinding mechanism (3), and the online sampling test component (8) comprises: A pole piece sampling device (81) for cutting pole piece samples online; and A moisture testing device (82), wherein the moisture testing device (82) is arranged in a position to receive the pole piece sample cut by the pole piece sampling device (81) and to test the moisture in the received pole piece sample.

2. The battery pole piece dewatering system according to claim 1, wherein: A deviation correction roller is arranged between the oven (2) and the winding mechanism (3), and the online sampling test assembly is arranged upstream of the deviation correction roller.

3. The battery pole piece dewatering system according to claim 1, wherein: The battery plate dewatering system further comprises: a control module; and a marking device located between the oven (2) and the winding mechanism (3), The control module receives the test result of the moisture testing device (82) in real time and identifies unqualified battery electrode parts based on the test result, and when an unqualified battery electrode part is identified, the control module instructs the marking device to mark the unqualified battery electrode part.

4. The battery pole piece dewatering system according to claim 1, wherein: The electrode piece sampling device (81) is located on the upper side of the battery electrode piece conveying path, and the moisture testing device (82) is located on the lower side of the battery electrode piece conveying path, and the positions of the electrode piece sampling device (81) and the moisture testing device (82) are arranged so that the electrode piece sample cut by the electrode piece sampling device (81) can fall into the moisture testing device (82) by gravity and / or a slide.

5. The battery pole piece dewatering system according to any one of claims 1 to 4, wherein: The battery electrode sheet dewatering system is constructed to further include an openable sealing cover (9), the winding mechanism (3) and the online sampling test assembly (8) are both located within the sealing cover (9), and the sealing cover (9) is sealedly connected to the oven (2) at the discharge port end of the oven (2).

6. The battery pole piece dewatering system according to claim 5, wherein: A desiccant is placed in the sealing cover (9), or an air inlet for blowing dry gas into the interior of the sealing cover (9) is provided at the sealing cover (9).

7. The battery pole piece dewatering system according to claim 5, wherein: The sealing cover (9) has a transparent observation window.

8. The battery pole piece dewatering system according to any one of claims 1 to 4, wherein: The pole piece sampling device (81) is a laser cutting machine, a mechanical cutting machine or an ultrasonic cutting machine.

9. The battery pole piece dewatering system according to any one of claims 1 to 4, wherein: The sampling position of the pole piece sampling device (81) is located at the edge of the coating area of ​​the battery pole piece (4).

10. The battery pole piece dewatering system according to any one of claims 1 to 4, wherein: The pole piece sampling device (81) cuts pole piece samples from the battery pole piece (4) at a fixed sampling frequency, or the pole piece sampling device (81) cuts pole piece samples from the battery pole piece (4) at a variable sampling frequency according to the stability of the battery pole piece water removal system.

11. A method for removing water from a battery pole piece used in a battery pole piece removal system according to any one of claims 1 to 10, wherein: During the operation of the battery pole piece dehumidification system, the battery pole piece (4) is subjected to an online sampling test via the online sampling test assembly (8).

12. The method for removing water from a battery pole piece according to claim 11, wherein: The battery plate dewatering method further comprises the following steps: When it is detected that the water content of the electrode sample exceeds the standard, the unqualified products are marked manually by the staff or automatically by the marking equipment.

13. The method for removing water from a battery pole piece according to claim 11, wherein: When the battery electrode sheet dewatering system is configured to further include an openable sealing cover (9), the winding mechanism (3) and the online sampling test assembly (8) are both located in the sealing cover (9), and the sealing cover (9) is in sealed communication with the oven (2) at the outlet end of the oven (2), Wherein, during the process of removing water from the battery pole piece (4), the sealing cover (9) is always kept closed.

14. The method for removing water from a battery pole piece according to claim 13, wherein: A desiccant is placed in the sealing cover (9), or a dry gas is continuously blown into the interior of the sealing cover (9) while the sealing cover (9) is closed.

Images