A method for preparing ultra-fine glass fiber battery separator

Abstract

The present invention relates to the technical field of battery separator preparation, and in particular to a method for preparing an ultra-fine glass fiber battery separator, comprising: step S1, obtaining a prepared separator substrate; step S2, placing the separator substrate inside a detection box to detect the preparation result; step S3, introducing a first preset gas from the bottom of the detection box into the inside of the detection box according to a preset gas introduction method, and detecting the bubble diameters at several positions in the first detection liquid within a preset time period to determine whether the pore structure of the separator substrate meets the preset standard; step S4, adjusting the control parameters of the preparation process of the separator substrate based on the judgment result of the pore structure of the separator substrate. The present invention can quickly and accurately detect the prepared separator substrate.

Description

Technical Field

[0001] The invention relates to the technical field of battery separator preparation, and in particular to a method for preparing an ultra-fine glass fiber battery separator. Background Art

[0002] Storage batteries are widely used, and their output value and output rank first among all kinds of chemical power sources worldwide. Separators are an important component of batteries. At present, ultra-fine glass fiber battery separators are a kind of separators that are widely used in domestic battery separators. The material itself is an electronic insulator, and its porosity helps to maintain the electrolyte required for the reaction of active substances, making it ion conductive. The resistance of the separator is an important property of the separator, which is determined by the size and distribution of the pore structure of the separator. The ultra-fine glass fiber battery separator, the state of its fibers interwoven and evenly distributed determines the pore structure of the separator, resulting in the following defects, such as large average pores, uneven pore distribution, and pore size changes caused by the smooth surface of the glass fiber when the pressure is high. The traditional method of detecting the pores of the separator is often achieved by manually irradiating the separator with ordinary light sources. The detection efficiency is relatively low, and it is difficult to ensure the detection quality, which makes it difficult for the detection results to support the adjustment of the preparation process. Summary of the invention

[0003] To this end, the present invention provides a method for preparing an ultra-fine glass fiber battery separator, so as to overcome the problem in the prior art that the efficiency of separator pore detection is low, resulting in a low qualified rate of the prepared separator pore structure.

[0004] To achieve the above object, the present invention provides a method for preparing an ultra-fine glass fiber battery separator, comprising:

[0005] Step S1, obtaining a prepared separator substrate;

[0006] Step S2, placing the partition substrate inside a detection box for detection;

[0007] The partition substrate is kept parallel to the bottom of the detection box, and a first preset height interval exists between the lower surface of the partition substrate and the bottom of the detection box; the detection box is filled with a first detection liquid so that the liquid level of the first detection liquid exceeds a second preset height of the upper surface of the partition substrate;

[0008] Step S3, introducing a first preset gas from the bottom of the detection box into the interior of the detection box according to a preset gas introduction method, and detecting the bubble diameters at several positions in the first detection liquid within a preset time period to determine whether the pore structure of the partition substrate meets the preset standard; the preset gas introduction method includes a first preset gas introduction method and a second preset gas introduction method;

[0009] Wherein, the first preset gas introduction method is to introduce gas into the interior of the detection box at a first preset gas flow rate within a preset time period;

[0010] The second preset gas introduction method is to introduce gas into the detection box body with the second preset gas flow rate as the initial gas flow rate and then uniformly change the flow rate to the first preset gas flow rate within a preset time period;

[0011] Step S4, adjusting the control parameters of the preparation process of the separator substrate based on the judgment result of the pore structure of the separator substrate.

[0012] Furthermore, in step S3, judging whether the pore structure of the separator substrate meets a preset standard includes:

[0013] Step S310, judging whether the pore structure of the partition substrate meets a preset standard based on the difference in bubble diameters on the upper and lower sides of the partition substrate in the first detection liquid;

[0014] Step S320, judging whether the pore structure of the partition substrate meets the preset standard based on the difference in bubble diameters obtained on the upper side of the partition substrate in the first detection liquid by the second preset gas introduction method and the first preset gas introduction method.

[0015] Furthermore, in step S3, judging whether the pore structure of the separator substrate meets a preset standard includes:

[0016] Step S311, judging whether the pore structure of the partition substrate meets the preset standard based on the comparison result of the difference between the average diameter of the bubbles on the upper side of the partition substrate and the average diameter of the bubbles on the lower side of the partition substrate in the first detection liquid and the first preset threshold and the second preset threshold;

[0017] Step S321, calculate a first comparison value and a second comparison value based on the bubble diameter obtained on the upper side of the partition substrate in the first detection liquid by the second preset gas introduction method and the first preset gas introduction method and the preset bubble diameter, and judge whether the pore structure of the partition substrate meets the preset standard based on the first comparison value and the second comparison value.

[0018] Further, in the step S321, it is determined whether the pore structure of the separator substrate meets the preset standard based on the comparison result of the difference between the first comparison value and the second comparison value and the third preset threshold value;

[0019] The first comparison value is determined according to a plurality of bubble diameters of the gas introduced into the first detection liquid on the upper side of the partition substrate by a first preset gas introduction method and a preset bubble diameter;

[0020] The second comparison value is determined according to a plurality of bubble diameters on the upper side of the partition substrate in the first detection liquid when the gas is introduced by a second preset gas introduction method and a preset bubble diameter.

[0021] Further, in the step S320, the difference in bubble diameters obtained by the second preset gas introduction method and the first preset gas introduction method on the upper side of the partition substrate in the first detection liquid is obtained by:

[0022] The preset time period is evenly divided into a plurality of portions, and an average value of bubble diameters of bubbles obtained by passing gas through the second preset gas passing method on the upper side of the partition substrate in the first detection liquid in each time period is calculated, as well as an average value of bubble diameters of bubbles obtained by passing gas through the first preset gas passing method on the upper side of the partition substrate in the first detection liquid in each time period;

[0023] According to the maximum value PX of each average value corresponding to the second preset gas introduction method in each time period and the maximum value PY of each average value corresponding to the first preset gas introduction method, the difference RC of the bubble diameters obtained by the second preset gas introduction method and the first preset gas introduction method on the upper side of the partition substrate in the first detection liquid is determined, then RC=abs(PY-PX); abs() is the preset absolute value determination function.

[0024] Furthermore, in the step S3, the determining whether the pore structure of the separator substrate meets the preset standard further includes:

[0025] Step S330, judging whether the pore structure of the partition substrate meets a preset standard based on a comparison result between an average diameter of bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter;

[0026] Step S340: judging whether the pore structure of the partition substrate meets a preset standard based on the variance between the diameters of a plurality of bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter.

[0027] Furthermore, in step S330, if the average diameter of the bubbles on the upper side of the partition substrate in the first detection liquid is greater than the preset bubble diameter, it is determined that the pore structure of the partition substrate does not meet the preset standard and the overall pore size of the partition substrate exceeds the standard preparation pore size.

[0028] Further, in the step S340, the variance between the diameters of several bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter is greater than or equal to a variance threshold, and it is judged that the pore structure of the partition substrate does not meet the preset standard and the pore structure of the partition substrate is unevenly distributed.

[0029] Further, in the step S321, if abs(A1-A2)>V2, it is judged that the pore structure of the partition matrix does not meet the preset standard and the pore structure retention of the partition matrix is ​​low; wherein V2 is the third preset threshold, A1 is the first comparison value, A2 is the second comparison value, and abs() is the preset absolute value determination function.

[0030] Further, the preset bubble diameter is determined according to the standard preparation pores of the separator substrate and the first preset gas flow rate.

[0031] Compared with the prior art, the beneficial effect of the present invention lies in that the present invention places the prepared partition substrate inside a detection box to detect the preparation results, and judges whether the pore structure of the partition substrate meets the preset standards by detecting the bubble diameters of several positions in the first detection liquid by introducing a first preset gas from the bottom of the detection box into the inside of the detection box by two different gas introduction methods. This can not only improve the detection efficiency, but also improve the detection accuracy.

[0032] Furthermore, the present invention uses the bubble diameters obtained by the two methods to jointly judge whether the pore structure of the partition substrate meets the preset standard, which can improve the detection accuracy.

[0033] Furthermore, the present invention determines whether the pore structure of the partition matrix meets the preset standards by detecting the average diameter of bubbles on the upper and lower sides of the partition matrix within a preset time period, thereby improving the accuracy of detection. Moreover, by calculating the first comparison value and the second comparison value for judgment, the influence of special circumstances can be avoided, thereby further improving the detection accuracy.

[0034] Furthermore, the present invention divides the preset time period into several parts on average, detects the bubbles corresponding to each time period to determine the maximum average value of the bubble diameter corresponding to each time period, and can determine the overall change of the bubbles. The difference in bubble diameter between the second preset gas introduction method and the first preset gas introduction method can thereby more accurately determine the pore detection situation.

[0035] Furthermore, the present invention can ensure the accuracy of detection by adding two more methods to jointly determine the detection condition of the partition substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 The present invention is a flow chart of a method for preparing an ultra-fine glass fiber battery separator;

[0037] Figure 2 It is a structural schematic diagram of the detection box of the present invention;

[0038] Figure 3A schematic diagram of a process for judging whether the pore structure of the separator substrate meets the preset standard according to the present invention;

[0039] Figure 4 It is a logic judgment diagram of the preparation method of the ultra-fine glass fiber battery separator of the present invention;

[0040] In the figure: 1. detection box; 2. first detection liquid; 3. partition substrate; 4. air hole. DETAILED DESCRIPTION

[0041] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0042] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0043] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0044] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] See also Figure 1 and Figure 2 As shown, Figure 1 The present invention is a flow chart of a method for preparing an ultra-fine glass fiber battery separator; Figure 2 It is a structural schematic diagram of the detection box of the present invention;

[0046] The present invention provides a method for preparing an ultra-fine glass fiber battery separator, comprising:

[0047] Step S1, obtaining a prepared separator substrate;

[0048] Step S2, placing the partition substrate inside a testing box to test the preparation results;

[0049] The partition substrate is kept parallel to the bottom of the detection box 1, and there is a gap of a first preset height between the lower surface of the partition substrate 3 and the bottom of the detection box 1; the first detection liquid 2 is filled in the detection box 1 so that the liquid level of the first detection liquid 2 exceeds the second preset height of the upper surface of the partition substrate 3;

[0050] During implementation, a plurality of air holes 4 are provided at the bottom of the detection box 1, and the interior of the detection box 1 is filled with the first detection liquid 2. The actual implementers can set the first preset height and the second preset height according to actual conditions. The first preset height is greater than the second preset height. Preferably, the first preset height is 1.3 to 1.5 times the second preset height.

[0051] Specifically, the first detection liquid 2 can be a liquid with a certain viscosity or the liquid can be mixed with a dye with a special color to facilitate bubble detection, or the color of the introduced gas can be distinguished from the color of the first detection liquid 2. The viscosity of the first detection liquid 2 is based on the ability to stably maintain the bubbles, which will not be elaborated here; the detection box 1 can be set to a transparent material, and an image acquisition device or other sensors that can detect or calculate the diameter of the bubbles in the first detection liquid 2 can be installed at corresponding positions outside the detection box 1.

[0052] Step S3, introducing a first preset gas from the bottom of the detection box into the interior of the detection box according to a preset gas introduction method, and detecting the bubble diameters at several positions in the first detection liquid within a preset time period to determine whether the pore structure of the partition substrate meets the preset standard; the preset gas introduction method includes a first preset gas introduction method and a second preset gas introduction method;

[0053] Wherein, the first preset gas introduction method is to introduce gas into the interior of the detection box at a first preset gas flow rate within a preset time period;

[0054] The second preset gas introduction method is to introduce gas into the detection box body with the second preset gas flow rate as the initial gas flow rate and uniformly change the flow rate to the first preset gas flow rate within a preset time period.

[0055] In practice, the second preset gas flow rate is 1.5 to 2.5 times the first preset gas flow rate. It is understandable that the first preset gas flow rate and the second gas flow rate in the present invention can be subjected to several gas flow tests at different flow rates according to the qualified partition substrate samples in the actual scene. Preferably, the gas flow rate in which the deformation amount of the partition substrate is less than 5% (maximum deformation amount / partition length dimension) is selected as the second gas flow rate. The first gas flow rate can be set accordingly according to the ratio between the first gas flow rate and the second gas flow rate. It can be selected according to the specific application scenario and will not be repeated here.

[0056] Specifically, the first preset gas can be any gas that does not react with the first detection liquid and the partition substrate, such as argon, neon, carbon dioxide, or argon, neon, carbon dioxide that has been dyed or mixed with marking particles.

[0057] The present invention places the prepared partition substrate inside a detection box to detect the preparation results, and judges whether the pore structure of the partition substrate meets the preset standard by detecting the bubble diameters of several positions in the first detection liquid by introducing a first preset gas from the bottom of the detection box into the inside of the detection box by two different gas introduction methods. This can not only improve the detection efficiency, but also improve the detection accuracy.

[0058] See also Figure 3 As shown, it is a schematic diagram of the process of judging whether the pore structure of the separator substrate meets the preset standard according to the present invention; specifically, in the step S3, judging whether the pore structure of the separator substrate meets the preset standard includes:

[0059] Step S310, judging whether the pore structure of the partition substrate meets a preset standard based on the difference in bubble diameters on the upper and lower sides of the partition substrate in the first detection liquid;

[0060] Step S320, judging whether the pore structure of the partition substrate meets the preset standard based on the difference in bubble diameters obtained on the upper side of the partition substrate in the first detection liquid by the second preset gas introduction method and the first preset gas introduction method.

[0061] The present invention uses the bubble diameters obtained by the two methods to jointly judge whether the pore structure of the partition substrate meets the preset standard, which can improve the detection accuracy.

[0062] Specifically, in step S3, judging whether the pore structure of the separator substrate meets the preset standard includes:

[0063] Step S311, judging whether the pore structure of the partition substrate meets the preset standard based on the comparison result of the difference between the average diameter of the bubbles on the upper side of the partition substrate and the average diameter of the bubbles on the lower side of the partition substrate in the first detection liquid and the first preset threshold and the second preset threshold;

[0064] Specifically, the difference between the average diameter of the bubbles on the upper side of the partition substrate and the average diameter of the bubbles on the lower side of the partition substrate in the first detection liquid is determined according to the following method:

[0065] Obtain the bubble diameters YB1, YB2, ..., YB2 on the upper side of the partition substrate in the first detection liquid after the gas is introduced by the first preset gas introduction method within a preset time period. j , …, YB m and the bubble diameters YJ1, YJ2, ..., YJ below the separator substrate i , …, YJ n , then the difference YC of the bubble diameters on the upper and lower sides of the partition substrate in the first detection liquid when the gas is introduced by the first preset gas introduction method is: YC = (∑ n i＝1 (YJ i )) / n-(∑ m j＝1 (YB j )) / m; wherein j=1, 2, ..., m; m is the number of bubbles introduced into the upper side of the gas partition substrate by the first preset gas introduction method within a preset time period; YB j is the bubble diameter of the jth bubble generated by the first preset gas introduction method into the upper side of the gas partition substrate within the preset time period; i=1, 2, ..., n; n is the number of bubbles introduced into the lower side of the gas partition substrate by the first preset gas introduction method within the preset time period; YJ i is the bubble diameter of the i-th bubble generated by introducing the gas into the lower side of the gas separator substrate by the first preset gas introduction method within a preset time period;

[0066] Obtain the bubble diameters EB1, EB2, ..., EB1 on the upper side of the partition substrate in the first detection liquid when the gas is introduced by the second preset gas introduction method within a preset time period. k , …, EB g and the bubble diameters EJ1, EJ2, ..., EJ on the lower side of the partition substrate f , …, E. J. h , then the difference EC of the bubble diameters on the upper and lower sides of the partition substrate in the first detection liquid when the gas is introduced by the second preset gas introduction method is: EC = (∑ h f＝1 (EJ f )) / h-(∑ g k＝1 (EBk )) / g; wherein k=1, 2, ..., g; g is the number of bubbles introduced into the upper side of the gas partition substrate by the second preset gas introduction method within a preset time period; EB k is the bubble diameter of the kth bubble generated by introducing the second preset gas introduction method into the upper side of the gas partition substrate within the preset time period; f=1, 2, ..., h; h is the number of bubbles introduced into the lower side of the gas partition substrate by the second preset gas introduction method within the preset time period; EJ f is the bubble diameter of the fth bubble generated by introducing the gas into the lower side of the gas separator substrate by the second preset gas introduction method within the preset time period;

[0067] According to YC and EC, the difference MC between the average diameter of the bubbles on the upper side of the partition substrate and the average diameter of the bubbles on the lower side of the partition substrate in the first detection liquid is determined, MC=(YC+EC) / 2.

[0068] Specifically, if the pores of the prepared partition matrix are too large, the partition strength will be relatively low. If the pores of the prepared partition matrix are too small, the liquid absorption capacity of the partition will be relatively poor. Therefore, if MC is greater than the first preset threshold and less than the second preset threshold, it is judged that the pore structure of the partition matrix does not meet the preset standards. In actual application scenarios, the actual implementers can set the first preset threshold and the second preset threshold based on the actual situation and conduct several pore bubble tests on the partition matrix samples for each qualification judgment to set the first preset threshold and the second preset threshold. The second preset threshold is greater than the first preset threshold. Preferably, the second preset threshold is 1.2 to 1.5 times the first preset threshold.

[0069] Step S321, calculate a first comparison value and a second comparison value based on the bubble diameter obtained on the upper side of the partition substrate in the first detection liquid by the second preset gas introduction method and the first preset gas introduction method and the preset bubble diameter, and judge whether the pore structure of the partition substrate meets the preset standard based on the first comparison value and the second comparison value.

[0070] Specifically, in the step S321, based on the comparison result of the difference between the first comparison value and the second comparison value and the third preset threshold, it is judged whether the pore structure of the separator substrate meets the preset standard;

[0071] The first comparison value is determined according to a plurality of bubble diameters of the gas introduced into the first detection liquid on the upper side of the partition substrate by a first preset gas introduction method and a preset bubble diameter;

[0072] In implementation, the first comparison value is determined by:

[0073] Obtain the bubble diameters YR1, YR2, ..., YR1 on the upper side of the partition substrate in the first detection liquid after the gas is introduced by the first preset gas introduction method within a preset time period.t , …, YR r ; Wherein, t = 1, 2, ..., r; r is the number of bubbles introduced into the upper side of the gas separator substrate by the first preset gas introduction method within a preset time period; YR t is the bubble diameter of the tth bubble generated by introducing the gas into the upper side of the gas separator substrate by the first preset gas introduction method within a preset time period;

[0074] The gas is introduced according to the first preset gas introduction method. The diameter of the bubble on the upper side of the partition substrate in the first detection liquid is compared with the preset bubble diameter LR to determine the first comparison value A1=(∑ r t＝1 (YR t -LR)) 2 ) / r.

[0075] The second comparison value is determined according to a plurality of bubble diameters on the upper side of the partition substrate in the first detection liquid when the gas is introduced by a second preset gas introduction method and a preset bubble diameter.

[0076] In implementation, the second comparison value is determined by:

[0077] Obtain the bubble diameters ER1, ER2, ..., ER3 on the upper side of the partition substrate in the first detection liquid after the gas is introduced by the second preset gas introduction method within a preset time period. q , …, ER p ; Wherein, q = 1, 2, ..., p; p is the number of bubbles introduced into the upper side of the gas partition substrate by the second preset gas introduction method within a preset time period; ER q is the bubble diameter of the qth bubble generated by introducing the gas into the upper side of the gas separator substrate by the second preset gas introduction method within a preset time period;

[0078] The gas is introduced according to the second preset gas introduction method. The bubble diameter on the upper side of the partition substrate in the first detection liquid is compared with the preset bubble diameter LR to determine the second comparison value A2=(∑ p q＝1 (YR q -LR)) 2 ) / p;

[0079] Specifically, the preset bubble diameter LR is determined based on the standard preparation pores of the partition substrate and the first preset gas flow rate, and can be calculated by taking the average value of the test results of several gas passage tests on the partition samples after the partition substrate has passed various qualification judgments (qualified liquid absorption capacity, qualified tensile strength, qualified capillary acid absorption height).

[0080] In practice, LR = d × (N a ×V b ×T c) / Q; where N a is the number of pores, V b is the first preset gas flow rate (unit: ml / s), T c is the preset time period (unit: s), Q is the gas flow ratio of the standard prepared pore (unit: ml / m); d is the first coefficient, and d is related to the gas pressure.

[0081] The present invention determines whether the pore structure of the partition matrix meets the preset standard by detecting the average diameter of bubbles on the upper and lower sides of the partition matrix within a preset time period, which can improve the accuracy of detection. In addition, by calculating the first comparison value and the second comparison value for judgment, it can avoid the influence of special circumstances and further improve the detection accuracy.

[0082] Specifically, in the step S320, the difference in bubble diameters obtained by the second preset gas introduction method and the first preset gas introduction method on the upper side of the partition substrate in the first detection liquid is obtained by:

[0083] The preset time period is evenly divided into a plurality of portions, and an average value of bubble diameters of bubbles obtained by passing gas through the second preset gas passing method on the upper side of the partition substrate in the first detection liquid in each time period is calculated, as well as an average value of bubble diameters of bubbles obtained by passing gas through the first preset gas passing method on the upper side of the partition substrate in the first detection liquid in each time period;

[0084] According to the maximum value PX of each average value corresponding to the second preset gas introduction method in each time period and the maximum value PY of each average value corresponding to the first preset gas introduction method, the difference RC of the bubble diameters obtained by the second preset gas introduction method and the first preset gas introduction method on the upper side of the partition substrate in the first detection liquid is determined, then RC=abs(PY-PX); abs() is the preset absolute value determination function.

[0085] The present invention divides the preset time period into several parts on average, detects the bubbles corresponding to each time period, and determines the maximum average value of the bubble diameter corresponding to each time period. The overall change of the bubbles can be determined, and the difference in bubble diameter between the second preset gas introduction method and the first preset gas introduction method can be used to more accurately determine the pore detection situation.

[0086] Specifically, in step S321, if abs(A1-A2)>V2, it is judged that the pore structure of the partition matrix does not meet the preset standard and the pore structure retention of the partition matrix is ​​low; wherein V2 is the third preset threshold, A1 is the first comparison value, A2 is the second comparison value, and abs() is the preset absolute value determination function.

[0087] In implementation, actual implementers may set the third preset threshold value based on the test results of several qualified separator substrate samples according to actual conditions. Preferably, the value range of the third preset threshold value may be set to 0.05-0.1.

[0088] See also Figure 4 As shown, it is a logic judgment diagram of the method for preparing the ultra-fine glass fiber battery separator of the present invention; specifically, in the step S3, the judgment of whether the pore structure of the separator matrix meets the preset standard also includes:

[0089] Step S330, judging whether the pore structure of the partition substrate meets a preset standard based on a comparison result between an average diameter of bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter;

[0090] Specifically, in step S330, if the average diameter of the bubbles on the upper side of the partition substrate in the first detection liquid is greater than the preset bubble diameter, it is judged that the pore structure of the partition substrate does not meet the preset standard and the overall pore size of the partition substrate exceeds the standard preparation pore.

[0091] In actual application scenarios, actual implementers can set the standard preparation pores based on the test results of several qualified separator matrix samples according to actual conditions, or determine the standard preparation pores of the separator matrix according to the performance requirements of the battery.

[0092] Step S340: judging whether the pore structure of the partition substrate meets a preset standard based on the variance between the diameters of a plurality of bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter.

[0093] Specifically, in step S340, if the variance of the diameters of several bubbles on the upper side of the partition substrate in the first detection liquid and the preset bubble diameter is greater than or equal to the variance threshold, it is judged that the pore structure of the partition substrate does not meet the preset standard and the pore structure of the partition substrate is unevenly distributed.

[0094] In implementation, actual implementers may set the variance threshold according to actual conditions. Preferably, the variance threshold may be set in the range of 0.2 to 0.4.

[0095] Specifically, step S4, adjusting the control parameters of the preparation process of the separator substrate based on the judgment result of the pore structure of the separator substrate;

[0096] After obtaining the judgment result of the pore structure of the separator substrate that the pore structure of the separator substrate does not meet the preset standard, and further determining that the reason for the failure is that the overall pore size of the separator substrate exceeds the standard preparation pore size or the pore structure of the separator substrate is unevenly distributed, the corresponding preparation process control parameter adjustment can be taken according to the specific reason for the failure, including:

[0097] When the overall pore size of the separator matrix exceeds the standard preparation pore size, adjust the natural dehydration time or adjust the pulp-to-net speed ratio or the fiber stirring time to reduce the overall pore size;

[0098] When the pore structure of the partition substrate is unevenly distributed, the moisture absorption vacuum degree or the grading ratio of the fiber size is adjusted to improve the uniformity of the pore structure distribution of the partition substrate.

[0099] The present invention determines the detection condition of the partition substrate through a variety of methods, which can ensure the accuracy of the detection, thereby accurately guiding the adjustment of the control parameters of the preparation process. As for the specific adjustment method, technical personnel in this field can select and set it according to the actual preparation. It can be implemented by any existing technology and will not be elaborated here.

[0100] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A method for preparing an ultra-fine glass fiber battery separator, characterized in that: include: Step S1, obtaining a prepared separator substrate; Step S2, placing the partition substrate inside a detection box for detection; The partition substrate is kept parallel to the bottom of the detection box, and a first preset height interval exists between the lower surface of the partition substrate and the bottom of the detection box; the detection box is filled with a first detection liquid so that the liquid level of the first detection liquid exceeds a second preset height of the upper surface of the partition substrate; Step S3, introducing a first preset gas from the bottom of the detection box into the interior of the detection box according to a preset gas introduction method, and detecting the bubble diameters at several positions in the first detection liquid within a preset time period to determine whether the pore structure of the partition substrate meets the preset standard; the preset gas introduction method includes a first preset gas introduction method and a second preset gas introduction method; Wherein, the first preset gas introduction method is to introduce gas into the interior of the detection box at a first preset gas flow rate within a preset time period; The second preset gas introduction method is to introduce gas into the detection box body with the second preset gas flow rate as the initial gas flow rate and then uniformly change the flow rate to the first preset gas flow rate within a preset time period; Step S4, adjusting the control parameters of the preparation process of the separator substrate based on the judgment result of the pore structure of the separator substrate.

2. The method for preparing the ultra-fine glass fiber battery separator according to claim 1, characterized in that: In step S3, judging whether the pore structure of the separator substrate meets the preset standard includes: Step S310, judging whether the pore structure of the partition substrate meets a preset standard based on the difference in bubble diameters on the upper and lower sides of the partition substrate in the first detection liquid; Step S320, judging whether the pore structure of the partition substrate meets the preset standard based on the difference in bubble diameters obtained on the upper side of the partition substrate in the first detection liquid by the second preset gas introduction method and the first preset gas introduction method.

3. The method for preparing the ultra-fine glass fiber battery separator according to claim 2, characterized in that: In step S3, judging whether the pore structure of the separator substrate meets the preset standard includes: Step S311, judging whether the pore structure of the partition substrate meets the preset standard based on the comparison result of the difference between the average diameter of the bubbles on the upper side of the partition substrate and the average diameter of the bubbles on the lower side of the partition substrate in the first detection liquid and the first preset threshold and the second preset threshold; Step S321, calculate a first comparison value and a second comparison value based on the bubble diameter obtained on the upper side of the partition substrate in the first detection liquid by the second preset gas introduction method and the first preset gas introduction method and the preset bubble diameter, and judge whether the pore structure of the partition substrate meets the preset standard based on the first comparison value and the second comparison value.

4. The method for preparing the ultra-fine glass fiber battery separator according to claim 3, characterized in that: In the step S321, based on the comparison result of the difference between the first comparison value and the second comparison value and the third preset threshold, it is judged whether the pore structure of the separator substrate meets the preset standard; The first comparison value is determined according to a plurality of bubble diameters of the gas introduced into the first detection liquid on the upper side of the partition substrate by a first preset gas introduction method and a preset bubble diameter; The second comparison value is determined according to a plurality of bubble diameters on the upper side of the partition substrate in the first detection liquid when the gas is introduced by a second preset gas introduction method and a preset bubble diameter.

5. The method for preparing the ultra-fine glass fiber battery separator according to claim 4, characterized in that: In the step S320, the difference in bubble diameters obtained by the second preset gas introduction method and the first preset gas introduction method on the upper side of the partition substrate in the first detection liquid is obtained by: The preset time period is evenly divided into a plurality of portions, and an average value of bubble diameters of bubbles obtained by passing gas through the second preset gas passing method on the upper side of the partition substrate in the first detection liquid in each time period is calculated, as well as an average value of bubble diameters of bubbles obtained by passing gas through the first preset gas passing method on the upper side of the partition substrate in the first detection liquid in each time period; According to the maximum value PX of each average value corresponding to the second preset gas introduction method in each time period and the maximum value PY of each average value corresponding to the first preset gas introduction method, the difference RC of the bubble diameters obtained by the second preset gas introduction method and the first preset gas introduction method on the upper side of the partition substrate in the first detection liquid is determined, then RC=abs(PY-PX); abs() is the preset absolute value determination function.

6. The method for preparing the ultra-fine glass fiber battery separator according to claim 1, characterized in that: In the step S3, the step of judging whether the pore structure of the separator substrate meets the preset standard further includes: Step S330, judging whether the pore structure of the partition substrate meets a preset standard based on a comparison result between an average diameter of bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter; Step S340: judging whether the pore structure of the partition substrate meets a preset standard based on the variance between the diameters of a plurality of bubbles on the upper side of the partition substrate in the first detection liquid and a preset bubble diameter.

7. The method for preparing the ultra-fine glass fiber battery separator according to claim 6, characterized in that: In step S330, if the average diameter of the bubbles on the upper side of the partition substrate in the first detection liquid is greater than the preset bubble diameter, it is determined that the pore structure of the partition substrate does not meet the preset standard and the overall pore size of the partition substrate exceeds the standard preparation pore size.

8. The method for preparing the ultra-fine glass fiber battery separator according to claim 7, characterized in that: In step S340, if the variance of the diameters of several bubbles on the upper side of the partition substrate in the first detection liquid and the preset bubble diameter is greater than or equal to the variance threshold, it is judged that the pore structure of the partition substrate does not meet the preset standard and the pore structure of the partition substrate is unevenly distributed.

9. The method for preparing the ultra-fine glass fiber battery separator according to claim 3, characterized in that: In the step S321, if abs(A1-A2)>V2, it is judged that the pore structure of the partition matrix does not meet the preset standard and the pore structure retention of the partition matrix is ​​low; wherein V2 is the third preset threshold, A1 is the first comparison value, A2 is the second comparison value, and abs() is the preset absolute value determination function.

10. The method for preparing the ultra-fine glass fiber battery separator according to claim 8, characterized in that: The preset bubble diameter is determined based on the standard preparation pore size of the separator substrate and the first preset gas flow rate.

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