Battery diaphragm liquid absorption detection device and battery diaphragm liquid absorption detection method

Abstract

The present invention discloses a battery diaphragm liquid absorption detection device and a battery diaphragm liquid absorption detection method, including: a moving mechanism, which is used to move the diaphragm into the detection liquid; a weighing mechanism, which is used to weigh the mass of the detection liquid in real time and generate a corresponding mass signal; a control module, which is electrically connected to the weighing mechanism, and the control module can receive the mass signal and calculate the received mass signal to obtain the liquid absorption of the diaphragm; and a display mechanism, which is electrically connected to the control module, and the display mechanism is used to display the result calculated by the control module. The battery diaphragm liquid absorption detection device in this embodiment calculates the liquid absorption of the diaphragm by weighing the detection liquid, which not only has a higher accuracy of the test result, but also can automatically calculate and display the liquid absorption of the diaphragm, and can monitor the change of the liquid absorption of the diaphragm in real time from the display mechanism.

Description

Technical Field

[0001] The present invention relates to the technical field of battery manufacturing, and in particular to a device and method for detecting the amount of liquid absorbed by a battery diaphragm. Background Art

[0002] The diaphragm is one of the four major materials of lithium-ion batteries, accounting for nearly 1 / 3 of the cost of lithium-ion batteries, and is a key internal component in lithium batteries. In lithium batteries, after the diaphragm absorbs the electrolyte, it can isolate the positive and negative electrodes to prevent short circuits while allowing the conduction of lithium ions. The diaphragm should maintain long-term stability in the electrolyte and not react with the electrolyte and electrode materials. Good wettability of the diaphragm with the electrolyte is conducive to improving the affinity between the diaphragm and the electrolyte, expanding the contact surface between the diaphragm and the electrolyte, thereby increasing ion conductivity and improving the battery's charge and discharge performance and capacity. The wettability of the diaphragm to the electrolyte can be measured by measuring its liquid absorption. The currently commonly used method for testing the amount of liquid absorbed by the diaphragm is to place one end of the diaphragm in the test liquid, use a stopwatch and a ruler to calculate the height of the test liquid climbing on the diaphragm within a certain period of time, and then calculate the amount of liquid absorbed by the diaphragm. The disadvantage of this method is that both stopwatch timing and ruler measurement are prone to errors, affecting the accuracy of the test results.

[0003] In view of this, it is necessary to develop a battery diaphragm liquid absorption detection device and a battery diaphragm liquid absorption detection method to solve the above problems. Summary of the invention

[0004] In view of the above problems, the present invention provides a battery diaphragm liquid absorption detection device and a battery diaphragm liquid absorption detection method which can more accurately measure the diaphragm liquid absorption.

[0005] According to a first aspect of the present invention, there is provided a device for detecting liquid absorption of a battery diaphragm, comprising:

[0006] A moving mechanism, which is used to move the diaphragm into the test liquid;

[0007] A weighing mechanism, which is used to weigh the mass of the test liquid in real time and generate a corresponding mass signal;

[0008] a control module electrically connected to the weighing mechanism, the control module being capable of receiving the mass signal and calculating the received mass signal to obtain the liquid absorption amount of the diaphragm; and

[0009] The display mechanism is electrically connected to the control module, and is used to display the result calculated by the control module.

[0010] This embodiment further comprises a clamping mechanism, which is used to clamp the diaphragm and subject the diaphragm to a predetermined pressure.

[0011] The clamping mechanism includes two clamping plates and a driving assembly for driving the two clamping plates to move, and the driving assembly can drive the two clamping plates to move closer to or farther from each other.

[0012] The splint is a transparent splint.

[0013] The driving assembly includes a first bracket, a first screw rod and a first driving motor. The first screw rod is rotatably mounted on the first bracket. The first driving motor is used to drive the first screw rod. The clamping plate is threadedly connected to the first screw rod.

[0014] There are two of the first screw rods and two of the first driving motors driving the first screw rods, and one clamping plate is installed on each of the two first screw rods.

[0015] The clamping mechanism also includes a second screw rod and a second drive motor. The second screw rod is arranged on the first bracket along the vertical direction. The second drive motor is transmission-connected to the second screw rod. The drive assembly is threadedly connected to the second screw rod.

[0016] The clamping mechanism is arranged on the moving mechanism, and the moving mechanism can drive the clamping mechanism to move.

[0017] The moving mechanism includes a second bracket, a third screw rod, a hanging part and a third driving motor. The third screw rod is arranged on the second bracket in a vertical direction. The hanging part is threadedly connected to the third screw rod. The hanging part is used to fix the diaphragm. The third driving motor is transmission-connected to the third screw rod to drive the third screw rod to rotate.

[0018] According to a second aspect of the present invention, a method for detecting the amount of liquid absorbed by a battery diaphragm is provided, which is performed based on the device for detecting the amount of liquid absorbed by a battery diaphragm as described in any of the above embodiments, and the method comprises the following steps:

[0019] fixing the diaphragm on the moving mechanism;

[0020] placing the test liquid on the weighing mechanism;

[0021] The diaphragm is clamped at a preset pressure using a clamping mechanism;

[0022] The membrane is at least partially immersed in the test fluid.

[0023] Implementing the embodiments of the present invention will have at least the following beneficial effects:

[0024] The diaphragm can be automatically placed in the test liquid through the moving mechanism, the mass of the test liquid can be weighed in real time through the weighing mechanism and a corresponding mass signal can be generated, the control module can receive the mass signal and perform corresponding calculations on the mass signal, and the display mechanism can display the result of the control module's calculation of the mass signal, thereby obtaining the amount of liquid absorbed by the diaphragm. The battery diaphragm liquid absorption detection device in this embodiment calculates the amount of liquid absorbed by the diaphragm by weighing the test liquid, which not only has a higher test result accuracy, but also can automatically calculate and display the amount of liquid absorbed by the diaphragm, and can monitor the changes in the amount of liquid absorbed by the diaphragm in real time from the display mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] in:

[0027] Figure 1 This is one of the structural schematic diagrams of a battery diaphragm liquid absorption detection device in one embodiment;

[0028] Figure 2 The second structural schematic diagram of a battery diaphragm liquid absorption detection device in one embodiment;

[0029] Figure 3 The third structural schematic diagram of a battery diaphragm liquid absorption detection device in one embodiment;

[0030] Figure 4 Schematic diagram of a flow chart of a method for detecting liquid absorption of a battery diaphragm in one embodiment;

[0031] In the figure: 100, moving mechanism; 110, driving structure; 111, second bracket; 112, third driving motor; 113, third screw; 120, hanging part; 200, weighing mechanism; 300, display mechanism; 400, diaphragm; 500, detection liquid; 600, clamping mechanism; 611, first bracket; 612, first screw; 613, first driving motor; 620, clamping plate; 631, second screw; 632, second driving motor. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0034] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0035] Reference Figure 1 In one embodiment of the present invention, a battery diaphragm liquid absorption detection device is provided, comprising a moving mechanism 100, a weighing mechanism 200, a control module (not shown in the figure) and a display mechanism 300. The moving mechanism 100 is used to move the diaphragm 400 into the detection liquid 500. The weighing mechanism 200 is used to weigh the mass of the detection liquid 500 in real time and generate a corresponding mass signal. The control module is electrically connected to the weighing mechanism 200. The control module can receive the mass signal and calculate the received mass signal to obtain the liquid absorption of the diaphragm 400. The display mechanism 300 is electrically connected to the control module, and the display mechanism 300 is used to display the result calculated by the control module. The battery diaphragm liquid absorption detection device in this embodiment calculates the liquid absorption of the diaphragm 400 by weighing the detection liquid 500. Not only is the accuracy of the test result higher, but it can also automatically calculate and display the liquid absorption of the diaphragm 400, and can monitor the change of the liquid absorption of the diaphragm 400 in real time from the display mechanism 300, so as to analyze other properties of the diaphragm 400.

[0036] Specifically, the calculation formula of the liquid absorption amount of the diaphragm 400 in this embodiment is: liquid absorption amount of the diaphragm 400 = weight of the detection liquid 500 before the diaphragm 400 is placed - weight of the detection liquid 500 after the diaphragm 400 is placed - volatility coefficient of the detection liquid 500 * test time. It should be noted that the weight of the detection liquid 500 after the diaphragm 400 is placed refers to the weight when the diaphragm 400 can no longer absorb liquid from the detection liquid 500.

[0037] Reference Figure 1 In this embodiment, the moving mechanism 100 includes a driving structure 110 and a hanging part 120, one end of the diaphragm 400 is fixed on the hanging part 120, and the driving structure 110 can drive the hanging part 120 to move and make the diaphragm 400 at least partially immersed in the detection liquid 500.

[0038] Preferably, the hanging part 120 is rod-shaped, the length direction of the hanging part 120 is in the horizontal plane, the weighing mechanism 200 is arranged below the hanging part 120, the detection liquid 500 is placed on the weighing mechanism 200, and the driving structure 110 can drive the hanging part 120 to move in the vertical direction.

[0039] Preferably, the diaphragm 400 is movably fixed on the hanging part 120, and the diaphragm 400 can move along the length direction of the hanging part 120. Specifically, the hanging part 120 is provided with a slide rail along its length direction, and a slider matching the slide rail is installed on the slide rail, and the slider can move on the slide rail. Specifically, the cross section of the slide rail perpendicular to its length direction is an isosceles trapezoid, and the upper side of the isosceles trapezoid is a short side. The slider is provided with a groove matching the slide rail, and the cross section of the groove perpendicular to its length direction is an isosceles trapezoid. The diaphragm 400 is fixed on the slider, and specifically, a clip is provided on the slider to clamp the diaphragm 400.

[0040] In this embodiment, the driving structure 110 includes a second bracket 111, a third driving motor 112 and a third screw 113. The third screw 113 is arranged on the second bracket 111 in the vertical direction. The hanging part 120 is threadedly connected to the third screw 113. The third driving motor 112 is connected to the third screw 113 to drive the third screw 113 to rotate. During the test of the liquid absorption amount of the diaphragm 400, each relevant parameter needs to be set to a preset value as much as possible to ensure the accuracy of the liquid absorption amount of the diaphragm 400. In this embodiment, it is necessary to accurately control the depth of the diaphragm 400 immersed in the detection liquid 500. Through the threaded cooperation between the third screw 113 and the hanging part 120, the distance that the hanging part 120 moves along the axis of the third screw 113 can be accurately controlled to control the depth of the diaphragm 400 immersed in the detection liquid 500.

[0041] In some other embodiments, the driving structure 110 includes a piston cylinder, the axial direction of the output shaft of the piston cylinder is vertical, the output shaft of the piston cylinder can move along its axial direction, and the hanging part 120 is arranged on the output shaft of the piston cylinder. In this embodiment, the hanging part 120 is controlled to move in the vertical direction by the piston cylinder. The piston cylinder can be a pneumatic cylinder or a hydraulic cylinder.

[0042] Reference Figure 1 The battery diaphragm liquid absorption detection device in this embodiment further includes a clamping mechanism 600, which is used to clamp the diaphragm 400 and subject the diaphragm 400 to a predetermined pressure. In this embodiment, since the diaphragm 400 absorbs different amounts of liquid under different squeezing forces, in order to ensure the accuracy of the amount of liquid absorbed by the diaphragm 400, in this embodiment, a predetermined pressure is applied to the diaphragm 400 through the clamping mechanism 600 to ensure the accuracy of the amount of liquid absorbed by the diaphragm 400.

[0043] The clamping mechanism 600 in this embodiment includes two clamping plates 620 and a driving assembly for driving the two clamping plates 620 to move. The two clamping plates 620 are arranged parallel and opposite to each other. The driving assembly can drive the two clamping plates 620 to move closer or farther away from each other, thereby applying a predetermined pressure value to the diaphragm 400 .

[0044] Preferably, the present embodiment further includes a pressure sensing sheet for sensing the pressure applied by the two clamping plates 620 to the diaphragm 400. Specifically, the pressure sensing sheet is attached to one side of the clamping plates 620 close to the diaphragm 400. By monitoring the pressure applied by the clamping plates 620 to the diaphragm 400, the accuracy of detecting the amount of liquid absorbed by the diaphragm 400 is further improved.

[0045] Preferably, the splint 620 is a transparent splint 620 , specifically, the splint 620 may be a glass splint 620 . By setting the splint 620 as a transparent splint 620 , it is convenient to observe the amount of liquid absorbed by the diaphragm 400 , for example, it is convenient to observe the climbing height of the detection liquid 500 on the diaphragm 400 .

[0046] Further preferably, the splint 620 is vertically arranged, and a scale is arranged on the splint 620 along its vertical direction. In this embodiment, the user can also make a preliminary calculation of the amount of liquid absorbed by the diaphragm 400 by observing the climbing height of the detection liquid 500 on the diaphragm 400.

[0047] Reference Figure 1 The driving assembly in this embodiment includes a first bracket 611, a first screw rod 612 and a first driving motor 613. The first screw rod 612 is rotatably mounted on the first bracket 611. The first driving motor 613 drives the first screw rod 612. The clamping plate 620 is threadedly connected to the first screw rod 612. Through the cooperation between the first screw rod 612 and the clamping plate 620, the moving distance of the clamping plate 620 along the axial direction of the first screw rod 612 can be accurately controlled.

[0048] Preferably, there are two first screw rods 612 and two first drive motors 613 . A clamping plate 620 is respectively installed on the two first screw rods 612 , and the two drive motors drive one first screw rod 612 respectively.

[0049] Preferably, both clamping plates 620 are provided with threaded holes and through holes, the threaded holes are used for threaded connection with one of the first screw rods 612, and the through holes are used for the other of the first screw rods 612 to pass through, wherein the outer diameter of the first screw rod 612 is slightly smaller than the diameter of the through holes.

[0050] In some other embodiments, the first screw rod 612 and the first drive motor 613 that drives the first screw rod 612 to rotate both have one. In this embodiment, the first screw rod 612 has a first part and a second part, and the threads of the first part and the second part have opposite rotation directions. The two clamping plates 620 are respectively threadedly connected to the first part and the second part. The first drive motor 613 can be controlled to move closer to or farther away from each other by forward and reverse rotation.

[0051] In some other embodiments, the driving assembly includes two piston cylinders, which are arranged opposite to each other, with the axial direction of the piston cylinders being horizontal, and the two clamping plates 620 are respectively installed at the ends of the output shafts of the two piston cylinders. By controlling the clamping plates 620 by the two piston cylinders, the two clamping plates 620 can be moved closer to or away from each other.

[0052] It should be noted that the clamping plate 620 in the above embodiments moves synchronously with the diaphragm 400. To achieve the synchronous movement of the clamping plate 620 and the diaphragm 400, the present invention provides the following two embodiments.

[0053] Embodiment 1, refer to Figure 1 In this embodiment, the clamping mechanism 600 is arranged on the moving mechanism 100, and the moving mechanism 100 can drive the clamping mechanism 600 to move. Specifically, the driving assembly is threadedly connected to the third screw rod 113, and specifically, the first bracket 611 is threadedly connected to the third screw rod 113. The driving assembly can move with the rotation of the third screw rod 113, and the moving path of the driving assembly is the same as that of the hanging part 120, thereby ensuring that the clamping plate 620 arranged on the driving assembly and the diaphragm 400 arranged on the hanging part 120 move synchronously.

[0054] Example 2, refer to Figure 2The clamping mechanism 600 in this embodiment further includes a second screw rod 631 and a second drive motor 632. The second screw rod 631 is arranged on the first bracket 611 in the vertical direction. The second drive motor 632 is in transmission connection with the second screw rod 631, and the drive assembly is threadedly connected to the second screw rod 631. In this embodiment, the second screw rod 631 and the third screw rod 113 are both arranged in the vertical direction. By rotating the second drive motor 632, the drive assembly can be controlled to move axially along the second screw rod 631. In this embodiment, the second screw rod 631 has the same outer diameter and pitch as the third screw rod 113, and the second drive motor 632 has the same rotation speed as the third drive motor 112, so as to achieve synchronous movement of the clamping plate 620 arranged on the drive assembly and the diaphragm 400 arranged on the hanging part 120.

[0055] Preferably, the clamping mechanism 600 in the first embodiment also includes a second screw rod 631 and a second drive motor 632. The second screw rod 631 is arranged on the first bracket 611 along the vertical direction. The second drive motor 632 is in transmission connection with the second screw rod 631, and the drive assembly is threadedly connected to the second screw rod 631. The second screw rod 631 can be used to control the drive assembly to move in the vertical direction, thereby adjusting the relative position of the clamping plate 620 and the diaphragm 400.

[0056] Reference Figure 3 In some embodiments, the weighing mechanism 200 has a plurality of diaphragms 400, and the hanging part 120 can be fixed with a plurality of diaphragms 400. In this embodiment, multiple diaphragms 400 can be detected at the same time. Specifically, the first screw rod 612 and the first drive motor 613 driving the first screw rod 612 each have a plurality of first screw rods 612, and each first screw rod 612 controls a pair of oppositely arranged clamping plates 620, specifically, the first screw rod 612 has a first part and a second part, and the first part and the second part have opposite thread rotation directions, and the two clamping plates 620 are respectively threadedly connected to the first part and the second part, and the first drive motor 613 can be controlled to move closer to or farther away from each other by forward and reverse rotation.

[0057] Reference Figure 1-Figure 3 The weighing mechanism 200 in this embodiment is a high-precision electronic scale for weighing the detection liquid 500. Specifically, the detection liquid 500 is placed in a container, and the container is placed on the high-precision electronic scale.

[0058] Reference Figure 1-Figure 3 The display mechanism 300 is a display screen. In this embodiment, the control module and the display mechanism 300 can be on the same mobile terminal, which can be a computer, a mobile phone, a tablet computer, etc.

[0059] Reference Figure 4One embodiment of the present invention further provides a method for detecting the amount of liquid absorbed by a battery diaphragm. The method is based on the device for detecting the amount of liquid absorbed by a battery diaphragm in the above embodiment. The method comprises the following steps:

[0060] S101: Fix the diaphragm 400 on the moving mechanism 100, specifically, on the hanging part 120.

[0061] S102: Place the testing liquid 500 on the weighing mechanism 200.

[0062] S103: The diaphragm 400 is clamped according to a preset pressure using the clamping mechanism 600, specifically, by clamping and applying pressure through two oppositely arranged clamping plates 620.

[0063] S104: at least partially immerse the diaphragm 400 in the detection liquid 500. Specifically, the diaphragm 400 is driven by the moving mechanism 100 to be immersed in the detection liquid 500.

[0064] The battery diaphragm liquid absorption detection method in this embodiment can make the measured liquid absorption of the diaphragm 400 more accurate because the control of various variables during the detection process is relatively accurate. In addition, the liquid absorption of the diaphragm 400 is calculated by the mass change of the detection liquid 500. Moreover, the detection method is simple in principle and easy to operate.

[0065] The above disclosure is only the preferred embodiment of the present invention, which certainly cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A battery diaphragm liquid absorption detection device, characterized in that: include: A moving mechanism, which is used to move the diaphragm into the test liquid; A weighing mechanism, which is used to weigh the mass of the test liquid in real time and generate a corresponding mass signal; A control module, which is electrically connected to the weighing mechanism, and is capable of receiving the mass signal and calculating the received mass signal to obtain the liquid absorption amount of the diaphragm; as well as A display mechanism, which is electrically connected to the control module, and is used to display the result calculated by the control module; The clamping mechanism is used to clamp the diaphragm and subject the diaphragm to a predetermined pressure; the clamping mechanism includes two clamping plates and a driving component for driving the two clamping plates to move, and the driving component can drive the two clamping plates to move closer to or farther from each other.

2. The battery diaphragm liquid absorption detection device according to claim 1, characterized in that: The splint is a transparent splint.

3. The battery diaphragm liquid absorption detection device according to claim 1, characterized in that: The driving assembly includes a first bracket, a first screw rod and a first driving motor. The first screw rod is rotatably mounted on the first bracket. The first driving motor is used to drive the first screw rod. The clamping plate is threadedly connected to the first screw rod.

4. The battery diaphragm liquid absorption detection device according to claim 3, characterized in that: There are two of the first screw rods and two of the first driving motors driving the first screw rods, and one clamping plate is installed on each of the two first screw rods.

5. The battery diaphragm liquid absorption detection device according to claim 3, characterized in that: The clamping mechanism also includes a second screw rod and a second drive motor. The second screw rod is arranged on the first bracket along the vertical direction. The second drive motor is transmission-connected to the second screw rod. The drive assembly is threadedly connected to the second screw rod.

6. The battery diaphragm liquid absorption detection device according to claim 1, characterized in that: The clamping mechanism is arranged on the moving mechanism, and the moving mechanism can drive the clamping mechanism to move.

7. The battery diaphragm liquid absorption detection device according to any one of claims 1 to 6, characterized in that: The moving mechanism includes a second bracket, a third screw rod, a hanging part and a third driving motor. The third screw rod is arranged on the second bracket in a vertical direction. The hanging part is threadedly connected to the third screw rod. The hanging part is used to fix the diaphragm. The third driving motor is transmission-connected to the third screw rod to drive the third screw rod to rotate.

8. A method for detecting liquid absorption of a battery diaphragm, characterized in that: Based on the battery diaphragm liquid absorption detection device as described in any one of claims 1 to 7 above, the method comprises the following steps: fixing the diaphragm on the moving mechanism; placing the test liquid on the weighing mechanism; The diaphragm is clamped at a preset pressure using a clamping mechanism; The membrane is at least partially immersed in the test fluid.

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