A lithium ion battery electrolyte wettability test device

Abstract

The utility model discloses a kind of lithium ion battery electrolyte wettability test equipment, it is related to battery technical field, including bottom plate, object table and lifting rod, the object table is installed on the bottom plate, two fixed columns are fixed in the both ends of the object table, lifting groove is set on each fixed column, the both ends of the lifting rod are placed in two lifting grooves respectively and with the groove wall of lifting groove sliding connection, lifting platform is connected on the lifting rod, multiple capillary tubes are connected in penetration on the lifting platform, the upper end of multiple capillary tubes is connected with a duct, negative pressure pump is installed on the lifting platform. The utility model designs lifting mechanism and negative pressure pump cooperation, can test the wettability difference of different electrolyte one-time, also can test the wettability of different pole piece to same electrolyte, and using acquisition mechanism design makes that data acquisition and analysis process is more convenient and efficient, easy to operate, improves experimental test efficiency.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a lithium-ion battery electrolyte wettability testing device. Background Technology

[0002] With the increasing global demand for clean energy, lithium-ion batteries, as important energy storage devices, have been widely used in electric vehicles, consumer electronics, and energy storage systems. Lithium-ion batteries possess advantages such as high energy density, long cycle life, and low self-discharge rate. Improving their performance depends on optimizing various components, with the electrolyte being a key component. The electrolyte plays a crucial role in conducting lithium ions within the battery, and its wettability directly affects the battery's electrochemical performance, cycle life, and safety. Electrolyte wettability refers to the electrolyte's ability to spread and penetrate the electrode material surface. Good wettability allows the electrolyte to fully contact the electrode material, reducing interfacial resistance and improving lithium-ion transport efficiency, thereby enhancing the battery's charge-discharge performance and cycle life. Conversely, poor wettability prevents the electrode material from functioning effectively, increasing the battery's internal resistance, reducing capacity and performance, and potentially even causing safety issues. Therefore, optimizing electrolyte formulations, selecting electrode materials, and improving battery manufacturing processes provides a basis for this research. Testing can reveal the impact of different electrolyte compositions, electrode materials, and manufacturing processes on wettability, thereby improving battery performance and reliability.

[0003] Currently, commonly used wetting test methods include: contact angle measurement, wetting time method, and liquid surface climb method. The contact angle measurement method assesses wettability by measuring the static contact angle of the electrolyte on a solid surface (a smaller contact angle indicates better wettability). This method only reflects the initial wetting state and cannot simulate the dynamic penetration in porous structures. It has large measurement errors for rough or porous electrodes (such as lithium battery electrodes), exhibits contact angle hysteresis, and it is difficult to obtain the complete wetting time and rate of the electrolyte on the electrode. The wetting time method involves dropping a certain amount of electrolyte onto the electrode and testing the time required for complete penetration. This method has poor repeatability and large errors. The liquid surface climb method involves vertically suspending the electrode in the electrolyte and observing the rise of the electrolyte on the electrode over a certain period of time. This method requires data recording at different time points, and the testing process is time-consuming; it requires precise control of experimental conditions (such as temperature and humidity), which places high demands on the operator's skills; it can only reflect the wetting performance of a local area and cannot comprehensively evaluate the wetting condition of the entire electrode or battery, and there is a lack of testing equipment for battery electrolyte wetting in the existing technology. Utility Model Content

[0004] The purpose of this invention is to solve the problems mentioned in the background art and to propose a lithium-ion battery electrolyte wettability testing device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A lithium-ion battery electrolyte wettability testing device includes a base plate, a platform, and a lifting rod. The platform is mounted on the base plate, and two fixed columns are fixed at both ends of the platform. Each fixed column has a lifting groove. The two ends of the lifting rod are respectively placed in the two lifting grooves and slidably connected to the groove walls. A lifting platform is connected to the lifting rod, and multiple capillary tubes are connected through the lifting platform. The upper ends of the multiple capillary tubes are connected to a common guide tube. A negative pressure pump is installed on the lifting platform. The end of the guide tube away from the capillary tube is connected to the negative pressure pump. The end of the capillary tube away from the guide tube is used to contact the battery electrode placed on the platform for wettability testing. A lifting mechanism is provided on the fixed columns to control the lifting and lowering of the capillary tubes to achieve contact with the battery electrode. A collection mechanism is provided at the end of the base plate away from the platform to collect the liquid level height in the capillary tubes to obtain the wettability results.

[0006] Preferably, the lifting mechanism includes a crossbeam, which is a hollow structure and fixed to the top of two fixed columns. A rotating shaft is rotatably connected in the lifting groove of each fixed column. The upper ends of the two rotating shafts extend into the interior of the crossbeam and are coaxially connected to a sprocket. The two sprockets are fitted with a chain. Each rotating shaft has a threaded section in the part located in the lifting groove. The two ends of the lifting rod are respectively connected to the threaded sections of the two rotating shafts by threads. The upper end of one of the rotating shafts extends to the outside of the crossbeam and is connected to a rocker wheel. The threads of the threaded sections on the two rotating shafts have the same direction of rotation.

[0007] Preferably, multiple capillaries on the lifting platform are arranged in a single row at equal intervals, and the lower ends of the multiple capillaries are at the same height.

[0008] Preferably, the acquisition mechanism includes a vision acquisition unit, a data analyzer, and a display screen. The vision acquisition unit, data analyzer, and display screen are all mounted on the base plate at one end away from the platform. The vision acquisition unit, data analyzer, and display screen are connected by a data cable. The vision acquisition unit faces the platform and the capillary tube.

[0009] Preferably, the visual acquisition device is a camera or a webcam.

[0010] Preferably, a control valve is installed on the conduit.

[0011] Preferably, the shelf is made of stainless steel and the capillary is made of transparent material.

[0012] Compared with the prior art, the advantages of this utility model are: This invention features a lifting mechanism and a negative pressure pump that work together to test the wettability differences of different electrolytes in a single test, as well as the wettability of the same electrolyte on different electrodes. The acquisition mechanism design makes data acquisition and analysis more convenient and efficient, and the operation is simple, thus improving the efficiency of experimental testing. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model.

[0014] Figure 2 This is a structural schematic diagram of the platform and lifting platform in this utility model.

[0015] Figure 3 This is a structural cross-sectional view of the platform and lifting platform in this utility model.

[0016] In the diagram: 1. Base plate, 2. Storage platform, 3. Fixed column, 4. Lifting groove, 5. Lifting rod, 6. Lifting platform, 7. Capillary tube, 8. Conduit, 9. Negative pressure pump, 10. Control valve, 11. Crossbeam, 12. Rotating shaft, 13. Chain, 14. Rocker wheel, 15. Vision acquisition device, 16. Data analyzer, 17. Display screen. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0018] Reference Figure 1-3 As shown, a lithium-ion battery electrolyte wettability testing device includes a base plate 1, a platform 2, and a lifting rod 5. The platform 2 is mounted on the base plate 1. Two fixing columns 3 are fixed at both ends of the platform 2. Each fixing column 3 has a lifting groove 4. The two ends of the lifting rod 5 are respectively placed in the two lifting grooves 4 and slidably connected to the groove walls of the lifting grooves 4. A lifting platform 6 is connected to the lifting rod 5. Multiple capillary tubes 7 are connected through the lifting platform 6. The upper ends of the multiple capillary tubes 7 share a common connection. A conduit 8 is connected to the lifting platform 6, and a negative pressure pump 9 is installed on the lifting platform 6. The end of the conduit 8 away from the capillary tube 7 is connected to the negative pressure pump 9. The end of the capillary tube 7 away from the conduit 8 is used to contact the battery electrode placed on the platform 2 for wettability testing. A lifting mechanism 101 is provided on the fixed column 3 to control the lifting and lowering of the capillary tube 7 to achieve contact with the battery electrode. A collection mechanism 102 is provided on the end of the base plate 1 away from the platform 2 to collect the liquid level in the capillary tube 7 to obtain the wettability results.

[0019] Furthermore, the lifting mechanism includes a crossbeam 11, which is a hollow structure and fixed to the top of two fixed columns 3. A rotating shaft 12 is rotatably connected in the lifting groove 4 on each fixed column 3. The upper ends of the two rotating shafts 12 extend into the interior of the crossbeam 11 and are coaxially connected to a sprocket. The two sprockets are fitted with a chain 13. Each rotating shaft 12 has a threaded section in the part located inside the lifting groove 4. The two ends of the lifting rod 5 are respectively connected to the threaded sections of the two rotating shafts 12 by threads. The upper end of one of the rotating shafts 12 extends to the outside of the crossbeam 11 and is connected to a rocker wheel 14. The threads on the threaded sections of the two rotating shafts 12 have the same thread direction.

[0020] Furthermore, multiple capillary tubes 7 on the lifting platform 6 are arranged in a single row at equal intervals, and the lower ends of the multiple capillary tubes 7 are at the same height, so that the multiple capillary tubes 7 simultaneously contact and abut against the battery electrode plates placed on the platform 2.

[0021] Furthermore, the acquisition mechanism includes a visual acquisition unit 15, a data analyzer 16, and a display screen 17. The visual acquisition unit 15, the data analyzer 16, and the display screen 17 are all mounted on the base plate 1 at one end away from the platform 2. The visual acquisition unit 15, the data analyzer 16, and the display screen 17 are connected by a data cable. The visual acquisition unit 15 faces the platform 2 and the capillary tube 7. The visual acquisition unit 15 is a camera or a webcam. The visual acquisition unit 15 is used to collect images of the liquid level in the capillary tube 7. The data analyzer 16 is used to analyze the images to determine the liquid level height and display the data on the display screen 17.

[0022] Furthermore, a control valve 10 is installed on the conduit 8. After the negative pressure pump 9 draws liquid from the capillary 7 through negative pressure, the control valve 10 is used to lock the liquid level in the capillary 7.

[0023] In addition, the shelf 2 is made of stainless steel, which can effectively prevent the electrolyte from corroding the shelf 2. The capillary tube 7 is made of transparent material, and the capillary tube 7 can be made of glass.

[0024] Working process and its principle: In use, first rotate the rocker wheel 14 to drive the two rotating shafts 12 to rotate synchronously via chain drive. Use the threaded control to raise the lifting platform 6 to the height of the capillary tube 7. Then, place the container containing the electrolyte on the platform 2, corresponding to multiple capillary tubes 7. Next, rotate the rocker wheel 14 in the opposite direction to lower the lifting platform 6, allowing the capillary tubes 7 to insert into the electrolyte. Open the control valve 10 to activate the negative pressure pump 9, allowing the capillary tubes 7 to draw the electrolyte to a certain height. Then, close the negative pressure pump 9 and the control valve 10. Remove the container containing the electrolyte. Place the electrode on the platform 2 and lower the lifting platform 6 until the lower end of the capillary tube 7 contacts and abuts the electrode. Activate the acquisition mechanism, allowing the vision acquisition device 15 to take pictures of the capillary tubes 7 every 30 seconds. The data analyzer 16 analyzes the images to determine the liquid level and displays the data on the display screen 17, thus achieving the wettability test. The specific test steps are as follows: Example 1 Testing the wettability of different electrolytes Five electrolytes with the same formula but different proportions were taken and labeled as samples 1, 2, 3, 4, and 5. The viscosities of samples 1, 2, 3, 4, and 5 were measured using a viscometer and found to be 3.21 mm. 2 / s, 4.08mm 2 / s, 4.82mm 2 / s, 5.62mm 2 / s, 6.62mm 2 / s, the electrolyte is placed at the lower end of the corresponding capillary tube 7, and the negative pressure pump 9 is used to draw it in so that the liquid height in the capillary tube 7 is uniformly controlled at 15mm. Then, the electrodes with the same compaction density are tested. By observing the height of the liquid level drop in the capillary tube 7 at different times, the measured data are statistically analyzed. The test is repeated 3 times. The measurement results are shown in Table 1 below.

[0025] Table 1: Wetting Results of Electrolytes with Different Viscosities

[0026] Based on the data in Table 1 above, the repeatability tests on electrolytes of different viscosities show that there is a certain correlation between electrolyte viscosity and wettability. The higher the viscosity of the electrolyte, the worse the wettability, indicating that this method can effectively distinguish and judge the wettability of electrolytes of different viscosities.

[0027] Example 2 Testing the wettability of the same electrolyte on electrodes with different compressibility After the electrode material is stirred, coated, rolled, sliced, weighed, measured, and baked, a spare electrode sheet is prepared. The spare electrode sheet is cut into thin sheets of the same shape and area using a tablet press. The thickness of the pretreated electrode sheet is measured using a micrometer, and the compaction density of the electrode sheet is calculated. Following the above operation, three electrode sheets of the same material with different compaction densities are prepared.

[0028] Take the prepared electrode sheets and label them as samples a, b, and c, respectively. Test the compressibility of sample a (1.25 g / cm³). 3 b (1.47 g / cm³) 3 c(1.68g / g / cm) 3 Electrolyte was placed at the lower end of the corresponding capillary tube 7, and the liquid level in the capillary tube was uniformly controlled at 15mm. Then, the electrode was tested. The height of the liquid level in the capillary tube 7 was observed at different times. The test was repeated 5 times, and the measured data were statistically analyzed.

[0029] Table 2: Electrolyte wetting results for electrodes with different compression ratios

[0030] Based on the data in Table 2 above, it can be seen that the wettability of the electrolyte decreases as the electrode density increases. This method has a good ability to determine the wettability of the same electrolyte on electrodes with different densities. At the same time, the equipment has a high degree of automation, which reduces operational errors in the experimental process.

[0031] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A lithium-ion battery electrolyte wettability testing device, characterized in that, The device includes a base plate 1, a platform 2, and a lifting rod 5. The platform 2 is mounted on the base plate 1. Two fixed columns 3 are fixed at both ends of the platform 2. Each fixed column 3 has a lifting groove 4. The two ends of the lifting rod 5 are respectively placed in the two lifting grooves 4 and are slidably connected to the groove walls of the lifting grooves 4. A lifting platform 6 is connected to the lifting rod 5. Multiple capillary tubes 7 are connected through the lifting platform 6. The upper ends of the multiple capillary tubes 7 are connected to a conduit 8. A negative pressure pump 9 is installed on the lifting platform 6. The end of the conduit 8 away from the capillary tubes 7 is connected to the negative pressure pump 9. The end of the capillary tubes 7 away from the conduit 8 is used to contact the battery electrode placed on the platform 2 for wettability testing. A lifting mechanism 101 is provided on the fixed column 3 to control the lifting and lowering of the capillary tubes 7 to achieve contact with the battery electrode. A collection mechanism 102 is provided on the end of the base plate 1 away from the platform 2 to collect the liquid level in the capillary tubes 7 to obtain the wettability results.

2. The lithium-ion battery electrolyte wettability testing device according to claim 1, characterized in that, The lifting mechanism 101 includes a crossbeam 11, which is a hollow structure and fixed to the top of two fixed columns 3. A rotating shaft 12 is rotatably connected in the lifting groove 4 on each fixed column 3. The upper ends of the two rotating shafts 12 extend into the interior of the crossbeam 11 and are coaxially connected to a sprocket. The two sprockets are fitted with a chain 13. Each rotating shaft 12 has a threaded section in the part located inside the lifting groove 4. The two ends of the lifting rod 5 are respectively connected to the threaded sections of the two rotating shafts 12 by threads. The upper end of one of the rotating shafts 12 extends to the outside of the crossbeam 11 and is connected to a rocker wheel 14. The threads on the threaded sections of the two rotating shafts 12 have the same direction of rotation.

3. The lithium-ion battery electrolyte wettability testing device according to claim 1, characterized in that, Multiple capillary tubes 7 on the lifting platform 6 are arranged in a single row at equal intervals, and the lower ends of the multiple capillary tubes 7 are at the same height.

4. The lithium-ion battery electrolyte wettability testing device according to claim 1, characterized in that, The acquisition mechanism 102 includes a vision acquisition unit 15, a data analyzer 16, and a display screen 17. The vision acquisition unit 15, the data analyzer 16, and the display screen 17 are all mounted on the base plate 1 at one end away from the platform 2. The vision acquisition unit 15, the data analyzer 16, and the display screen 17 are connected by a data cable. The vision acquisition unit 15 is directly facing the platform 2 and the capillary tube 7.

5. The lithium-ion battery electrolyte wettability testing device according to claim 4, characterized in that, The visual acquisition device 15 is either a camera or a webcam.

6. The lithium-ion battery electrolyte wettability testing device according to claim 1, characterized in that, A control valve 10 is installed on the conduit 8.

7. The lithium-ion battery electrolyte wettability testing device according to claim 1, characterized in that, The shelf 2 is made of stainless steel, and the capillary tube 7 is made of transparent material.

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