Electrochemical cell mold for in-situ gas production detection

Abstract

The utility model discloses an electrochemical cell mold for in-situ gas production detection. The electrochemical cell mold comprises a mold base, the movable rod is rotatably arranged on the mold base; the diaphragm bag is fixedly connected with the movable rod, a pole piece with a first pole lug is arranged in the diaphragm bag, and the movable rod can roll the diaphragm bag through rotation; the diaphragm is arranged on the mold base; the mold upper shell is arranged on the mold base; the pressure assembly is arranged on the mold upper shell and is used for pressurizing the positive pole piece, the negative pole piece and the pole piece; the multiple metal rods are movably arranged on the mold upper shell, and the metal rods are used for forming a conductive path when abutting against the first tab and the third tab; the flexible sensor is arranged on the pressure assembly and used for detecting the pressure output by the pressure assembly. According to the electrochemical cell mold for in-situ gas production detection, the SOC of a symmetrical battery is controllable through rotation of the movable rod, the mold does not need to be disassembled, damage to a pole piece is reduced, and the gas production behavior of a single pole piece can be accurately detected.

Description

Technical Field

[0001] The utility model relates to the technical field of electrochemical cell structures, and more specifically, to an electrochemical cell mold for in-situ gas production detection. Background Art

[0002] Gas production during battery cycling is an important issue currently concerned in material development. However, current detection methods for generated gas mostly use instrument tests such as gas chromatography, which can only obtain results after the battery has generated sufficient gas after multiple cycles, and cannot analyze which side reactions may occur between the electrolyte and the material during cycling. In recent years, a mass spectrometer can obtain real-time gas production information of the battery through combination with an electrochemical cell. However, the design of a conventional electrochemical cell cannot conveniently obtain gas production behavior data of a single electrode and cannot accurately control the contact pressure between the positive and negative electrodes inside. Therefore, due to certain differences in cycling performance compared with conventional batteries, it may affect the gas production behavior, interfere with the analysis of the mechanism, and further directions for material improvement.

[0003] In summary, how to detect gas production behavior data of a single electrode is an urgent problem for those skilled in the art at present. Summary of the Utility Model

[0004] In view of this, the purpose of the utility model is to provide an electrochemical cell mold for in-situ gas production detection, which can achieve controllable SOC of a symmetric battery through the rotation of a movable rod, without disassembling the mold or the battery and reassembling it, reducing the damage to the electrode sheet by the external environment after disassembling the battery, and thus can accurately detect the gas production behavior of a single electrode sheet.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] An electrochemical cell mold for in-situ gas production detection, comprising:

[0007] A mold base;

[0008] A movable rod rotatably arranged on the mold base;

[0009] A diaphragm bag fixedly connected to the movable rod, with an electrode sheet with a first tab arranged inside the diaphragm bag, and the movable rod can realize the winding of the diaphragm bag through rotation;

[0010] A diaphragm arranged on the mold base, with a positive electrode sheet and a negative electrode sheet respectively arranged on both sides of the diaphragm, and third tabs are arranged on both the positive electrode sheet and the negative electrode sheet;

[0011] A mold upper shell arranged on the mold base;

[0012] A pressure component is provided on the upper mold shell, and the pressure component is used to apply pressure to the positive electrode plate, the negative electrode plate, and the electrode plate.

[0013] There are multiple metal rods, and the multiple metal rods are movably arranged on the upper mold shell. When the metal rods abut against the tab, they are used to form an electrical conduction path.

[0014] A flexible sensor is provided on the pressure component and is used to detect the pressure output by the pressure component.

[0015] Preferably, a passage is provided on the side of the mold base and the upper mold shell, and the passage is used to realize gas circulation. A porous separation membrane for blocking some electrolyte molecules is provided in the passage.

[0016] Preferably, a first seal and a second seal are provided on the pressure component, and the first seal and the second seal are used in cooperation to isolate the internal environment of the mold from the external environment.

[0017] Preferably, it further includes fixing rods. There are at least three fixing rods, and the fixing rods are fixed to the mold base. Both ends of the diaphragm are respectively connected to two of the fixing rods, and the diaphragm bag is arranged between the bent diaphragms.

[0018] Preferably, a second tab is provided on the side of the diaphragm corresponding to the positive electrode plate.

[0019] Preferably, a plurality of fixing holes are provided on the mold base, and a plurality of fixing components corresponding to the fixing holes are provided on the upper mold shell.

[0020] Preferably, it further includes a control system. The control system is connected to the passage and is used to control the opening degree of the passage. The metal rod is used to be connected to a detection fixture, and the flexible sensor is used to receive the pressure signal of the pressure component. The control system adjusts the pressure output by the pressure component according to the detection result to preset pressure.

[0021] Preferably, the positive electrode plate is placed on the mold base. A first active material layer is provided between the positive electrode plate and the diaphragm. The negative electrode plate is placed between the diaphragm and the upper mold shell. A second active material layer is provided between the negative electrode plate and the diaphragm. Third active material layers are provided on both sides of the electrode plate in the diaphragm bag.

[0022] Preferably, a transfer interface is provided on the upper mold shell. The transfer interface is used to connect to a computer. The control system is connected to the transfer interface, and the flexible sensor is connected to the transfer interface.

[0023] An electrochemistry cell mold for in-situ gas production detection provided by the present utility model has a rotatable movable rod arranged on the mold base. The movable rod is fixedly connected to a diaphragm bag. By rotating the movable rod, the diaphragm bag can be withdrawn. The diaphragm bag contains a pole piece with a tab. If it is necessary to test the gas production behavior of a single positive electrode, both the positive and negative electrodes corresponding to the two reference electrodes are positive electrode materials, and the negative electrode is in the diaphragm bag. The specified SOC positive and negative electrodes are obtained by circulating with the reference electrodes respectively. Then, by rotating the movable rod, the diaphragm bag together with the negative electrode is withdrawn. The remaining pole piece can normally perform symmetric cell cycling. The fixed connection between the movable rod and the diaphragm bag can achieve controllable SOC of the symmetric cell, without the need to disassemble the mold or the battery and reassemble it. Accordingly, the damage to the pole piece by the external environment after disassembling the battery is avoided, and thus the gas production behavior of a single pole piece can be accurately detected. The cooperation of the pressure assembly and the flexible sensor can ensure that the contact pressure of the pole piece is consistent during each detection process, making the pressure control more accurate and allowing the pressure to be changed during the test without disassembling the mold, maintaining the stability of the environment inside the battery. In addition, using a movable metal rod as the electrode can meet the requirement that multiple test instruments can be detected simultaneously through clamps, monitor the voltage during normal charge and discharge, test CV (Cyclic Voltammetry), test the interface impedance, etc., and this design is simple without redundant auxiliary circuits. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only the embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on the provided drawings.

[0025] Figure 1 It is the top view of the mold base provided by the present utility model;

[0026] Figure 2 It is the side view of the mold base provided by the present utility model;

[0027] Figure 3 It is the top view of the mold upper shell provided by the present utility model;

[0028] Figure 4 It is the side view of the mold upper shell provided by the present utility model;

[0029] Figure 5 It is the gas generation rate curve measured by the comparative example of the present utility model;

[0030] Figure 6 It is the gas generation rate curve measured by Embodiment 1 of the present utility model;

[0031] Figure 7 For the single electrode EIS (Electrochemical Impedance Spectroscopy) measured in Embodiment 2 of the present utility model and the conventional positive and negative electrode EIS.

[0032] Reference numerals:

[0033] 1 - Third tab; 2 - Electrode tab; 3 - First tab; 4 - Mold base; 5 - Diaphragm bag; 6 - Passage; 7 - Diaphragm; 8 - Fixed rod; 9 - Movable rod; 10 - Metal rod; 11 - Fixing component; 12 - Mold top; 13 - Pressure component; 14 - First seal; 15 - Second seal; 16 - Flexible sensor; 17 - Second tab; 18 - Adapter. Detailed implementation manners

[0034] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0035] The core of the present utility model is to provide an electrochemical cell mold for in-situ gas production detection. This mold does not need to be disassembled, reduces the damage to the electrode tab, and can accurately detect the gas production behavior of a single electrode tab.

[0036] An electrochemical cell mold for in-situ gas production detection provided by the present application includes: a mold base 4, a movable rod 9, a diaphragm bag 5, a mold upper shell 12, a pressure component 13, a metal rod 10, and a flexible sensor 16;

[0037] Among them, the movable rod 9 is rotatably arranged on the mold base 4;

[0038] The diaphragm bag 5 is fixedly connected to the movable rod 9. An electrode tab 2 with a first tab 3 is arranged in the diaphragm bag 5, and the movable rod 9 can wind up the diaphragm bag 5 by rotation;

[0039] The diaphragm 7 is arranged on the mold base 4. A positive electrode tab and a negative electrode tab are respectively arranged on both sides of the diaphragm 7, and a third tab 1 is arranged on both the positive electrode tab and the negative electrode tab;

[0040] The mold upper shell 12 is arranged on the mold base 4;

[0041] The pressure component 13 is arranged on the mold upper shell 12, and the pressure component 13 is used to pressurize the positive and negative electrode tabs and the electrode tab 2;

[0042] A plurality of metal rods 10 are provided. The plurality of metal rods 10 are movably arranged on the upper mold shell 12. When the metal rod 10 abuts against the first pole ear 3, it is used to form an electrical conduction path.

[0043] The flexible sensor 16 is arranged on the pressure assembly 13 and is used to detect the pressure output by the pressure assembly 13.

[0044] Specifically, please refer to the appendix Figure 2 , a rotatable movable rod 9 is arranged on the mold base 4. A diaphragm bag 5 is connected to the left side of the movable rod 9. A pole piece 2 with a first pole ear 3 is arranged in the diaphragm bag 5. If it is necessary to test the gas production behavior of a single positive electrode, the positive and negative electrodes are the positive electrode materials, and the negative electrode is in the diaphragm bag 5. They are respectively circulated with the reference electrode to obtain the positive and negative electrodes of the specified SOC (state of charge, that is, the state of charge). Then, by rotating the movable rod 9, the diaphragm bag 5 is taken away together with the negative electrode. The remaining pole piece 2 can normally perform symmetric battery cycling. Please refer to the appendix Figure 4 , a pressure assembly 13 is arranged on the upper mold shell 12. The pressure assembly 13 is used to abut against one side surface of the pole piece 2 and is provided with a flexible sensor 16, so as to facilitate the regulation of the pressure applied to the pole piece 2. For example, a larger pressure is applied during symmetric battery testing, the pressure is reduced when the reference electrode needs to be taken away, and the same pressure is reapplied after taking away, so as to ensure the consistency of the test conditions. There is no need to control the pressure by adding gaskets on the top of the mold, which makes the pressure control more accurate and the pressure can be changed during the test without disassembling the mold, keeping the environment inside the battery stable; when symmetric battery testing is not required, but it is necessary to test parameters such as the impedance / CV / voltage of a single pole piece during the normal cycling process, a lithium metal reference electrode can be connected to the reference electrode side, and three-electrode testing can be stably carried out.

[0045] In addition, a metal rod 10 that can move in the vertical direction is arranged on the upper mold shell 12. The position of the metal rod 10 in the vertical direction corresponds to that of the first pole ear 3. When the metal rod 10 abuts against the first pole ear 3 on the positive and negative pole pieces respectively, an electrical conduction path can be formed for charging and discharging. Selecting the movable metal rod 10 as the electrode can meet the detection of multiple test instruments through jigs at the same time. The voltage can be monitored during normal charging and discharging, CV can be tested, and the interface impedance can be tested, etc. Moreover, this design is simple and does not require redundant auxiliary circuits.

[0046] On the basis of the above embodiments, a passage 6 is provided on the side parts of the mold base 4 and the upper mold shell 12. The passage 6 is used to realize gas circulation, and a porous separation membrane for blocking some electrolyte molecules is arranged in the passage 6.

[0047] Specifically, passages 6 allowing gas to flow through are provided at any positions on both sides of the mold base 4 and the mold upper shell 12, and there is a layer of porous separation membrane in the passages inside the mold to prevent some electrolyte molecules from passing through, avoiding electrolyte leakage while ensuring air circulation.

[0048] Based on the above embodiments, a first seal 14 and a second seal 15 are provided on the pressure assembly 13, and the first seal 14 and the second seal 15 are used in cooperation to isolate the internal environment of the mold from the external environment.

[0049] Specifically, the first seal 14 is preferably a hollow screw sleeved on the end of the pressure assembly 13 located on the upper surface of the mold upper shell 12. The hollow screw can complete the positioning of the pressure assembly 13. At the same time, when determining the pressure that the pressure assembly 13 needs to output, the hollow screw should be tightened to isolate the inside of the mold from the outside. A second seal 15 is provided on one side of the pressure assembly 13 inside the mold upper shell 12. The second seal 15 is preferably an O-ring, which is also used to isolate the inside of the mold from the outside.

[0050] Based on the above embodiments, it further includes fixing rods 8. There are at least three fixing rods 8. The fixing rods 8 are fixed to the mold base 4. Both ends of the diaphragm 7 are respectively connected to two fixing rods 8, and the diaphragm bag 5 is arranged between the bent diaphragms 7.

[0051] Specifically, the fixing rods 8 at least include an upper fixing rod, a lower fixing rod and a single-side fixing rod. The upper fixing rod and the lower fixing rod are arranged on the same side of the mold base 4, and the upper fixing rod is located above the lower fixing rod. The single-side fixing rod is arranged on the other side of the mold base 4, so that the three fixing rods 8 form a triangular structure. The upper fixing rod and the lower fixing rod are fixedly connected to the two ends of the diaphragm 7, and the diaphragm 7 bypasses the single-side fixing rod. At this time, the single-side fixing rod plays a limiting role. The role of the diaphragm 7 is to prevent the diaphragm 7 from wrinkling and the displacement of the electrode plate 2 caused by the fluctuation of the diaphragm 7 during the process of removing the diaphragm bag 5 containing the electrode plate.

[0052] Based on the above embodiments, a second tab 17 is provided on the side of the diaphragm 7 corresponding to the diaphragm bag 5.

[0053] Specifically, both ends of the second tab 17 are respectively connected to the diaphragm 7 and the diaphragm bag 5 to form an electrically conductive path without contacting the positive and negative electrodes. The specific connecting components between its positive and negative electrodes are the positive electrode, the diaphragm 7, the second tab 17, the diaphragm bag 5, the electrode plate 2, the diaphragm 7, and the negative electrode.

[0054] Based on the above embodiments, a plurality of fixing holes are provided on the mold base 4, and a plurality of fixing components 11 corresponding to the fixing holes are provided on the mold upper shell 12.

[0055] Specifically, a sealing layer is provided at the edge of the mold base 4, generally selected as a sealing soft rubber. After the mold upper shell 12 is buckled on the mold base 4, the mold base 4 and the mold upper shell 12 can be fixedly connected through a plurality of fixing components 11, and the sealing soft rubber can isolate the inside and outside of the mold.

[0056] Optionally, the fixing component 11 is preferably a screw, and the fixing hole is correspondingly provided as a threaded hole, which is convenient for installation and has a low cost.

[0057] On the basis of the above embodiments, a control system is further included. The control system is connected to the passage 6 and is used to control the opening degree of the passage 6. The metal rod 10 is used to connect with the detection fixture, and the flexible sensor 16 is used to receive the pressure signal of the pressure component 13. The control system adjusts the pressure output by the pressure component 13 according to the detection result to preset pressure.

[0058] Specifically, the flexible sensor 16 can detect the pressure output by the pressure component 13 and transmit the corresponding electrical signal to the control system. The control system can control the output pressure of the pressure component 13 to ensure that each time the pressure component 13 is adjusted, the output pressure of the pressure component 13 on the pole piece 2 is the same.

[0059] On the basis of the above embodiments, a positive pole piece is placed on the mold base 4. A first active material layer is provided between the positive pole piece and the separator 7. A negative pole piece is placed between the separator 7 and the mold upper shell. A second active material layer is provided between the negative pole piece and the separator 7. Third active material layers are provided on both sides of the pole piece 2 in the separator bag 5.

[0060] Specifically, active material layers are provided on the positive pole piece, the negative pole piece, and the pole piece 2 in the separator bag 5. The active material layers at these three positions are not the same substance. Generally, the active material layer of the pole piece on the mold base 4 corresponds to the positive pole, and ternary or lithium iron phosphate in a lithium-ion battery, or layered metal oxide, polyanion, Prussian white, etc. in a sodium-ion battery can be selected. The active material layer on the pole piece 2 in the separator bag 5 can be the above-mentioned positive pole active material type or negative pole active material type according to requirements, such as graphite, hard carbon, etc.

[0061] Generally, when a symmetric battery test needs to be performed, the first active material layer and the second active material layer are the same active material, such as a positive pole active material (ternary or lithium iron phosphate in a lithium-ion battery, etc.), and the third active material layer is a different active material, such as a negative pole active material (graphite, etc.).

[0062] On the basis of the above embodiments, a transfer interface 18 is provided on the mold upper shell 12, and the transfer interface 18 is used to connect to a computer.

[0063] Specifically, the adapter 18 is connected to the flexible sensor 16, and the output pressure of the pressure component 13 can be connected to and displayed on a computer through the adapter 18 of the flexible sensor 16, so as to enable real-time monitoring of the output pressure and facilitate the regulation of the pressure according to the actual situation.

[0064] On this basis, the present application also discloses the specific implementation processes of two above-mentioned electrochemical cell molds and a comparative example:

[0065] Example 1: First, place the positive electrode tab with the third tab 1 on the mold base 4, with the side coated with the active material of the positive electrode tab facing upward. Then, fix one end of the separator 7 to a fixing rod 8 (usually the lower fixing rod) on the mold base 4, and then pass the separator 7 through the single-sided fixing rod on the other side. Next, place the separator bag 5 containing the negative electrode tab coated with active materials on both sides inside. Fix one side of the separator bag 5 to the movable metal rod 10 and rotate and wind until the separator has no wrinkles. Then, cover the separator 7 located at the single-sided fixing rod on the separator bag 5 and fix it to the upper fixing rod on the right side. After that, place the corresponding negative electrode tab at the corresponding position of the tab 2, with the active material facing downward. When a symmetrical battery test needs to be performed later, the active material on this negative electrode tab needs to be the same as the active material on the corresponding positive electrode tab. Pad a layer of sealing soft rubber around the mold base 4, cover the upper mold shell 12, and tighten the surrounding screws. Then, rotate the metal rods 10 corresponding to the first tab 3 and the third tab 1 downward to contact the first tab 3 and the third tab 1. After that, use an external pressure application tool such as the pressure component 13 to apply a pressure of 100 kg to the intermediate pressure application metal part. The pressure is connected to and displayed on a computer through the adapter 18 connected to the flexible sensor 16. Then, rotate the nut to make it in close contact with the sealing ring for sealing. Subsequently, connect the positive electrode to the positive electrode metal rod and the negative electrode to the reference metal rod for charging until 100% SOC. Similarly, connect the positive electrode on the other side to the positive electrode for charging and then discharging to 0% SOC. Then, rotate the reference metal rod upward, remove the pressure applied on the pressure component 13, rotate the movable screw until the reference electrode is completely wound up. Reapply the same pressure, and rotate the metal rods 10 corresponding to each tab to connect to the tabs for symmetrical battery cycling while detecting the voltage of a single electrode. At this time, introduce the gas in the mold into the mass spectrometer through the carrier gas, and the obtained gas generation rate is the real-time gas generation rate during the single positive electrode cycling process. The influence on the gas generation behavior can be determined through the modification analysis of the material / different ratios of the electrolyte, and it can further help optimize the gas generation performance of the material and the stability of the electrolyte.

[0066] Example 2: The assembly method of the mold is the same, except that the negative electrode in the diaphragm bag 5 is changed to the second ear 17 wrapped with lithium metal. Of course, the diaphragm bag may not be needed and it can be directly placed between the positive and negative electrodes. During the detection process, the positive electrode is connected to the positive electrode, the negative electrode is connected to the counter electrode, and the lithium metal ear is connected to the reference electrode. During the cycling process, the electrochemical test of a single ear under the corresponding state can be carried out at any time to help analyze the redox reaction or interface impedance transformation of different materials during the cycling process, and guide the modification or optimization of materials or electrolytes;

[0067] Comparative example: The battery with the specified SOC for charging is disassembled to obtain two pieces of positive electrode materials respectively. The positive electrode diaphragm and the positive electrode are assembled in the mold in the placement method. Then, gaskets with similar heights are placed by measuring the height between the electrode plate and the top, and the mold is closed and fixed. The test is carried out by connecting to the test instrument through the positive and negative electrodes to obtain the gas generation rate curve changing with the cycling process;

[0068] Two gas generation rate curves can be obtained from the comparative example and Example 1. Please refer to the appendix Figure 5 And the appendix Figure 6 , in Example 2, the single electrode or the conventional positive and negative electrode EIS measured through the reference electrode can decompose the conventional positive and negative electrode EIS. For details, please refer to the appendix Figure 7 , the test results of the comparative example are as shown in the appendix Figure 6 . It can be seen that the gas generated during the charge and discharge process is more complex, and the two peaks from the end of discharge to the initial stage of charge cannot distinguish whether it is the gas generation reaction of the positive electrode or the negative electrode, which is not conducive to the mechanism analysis aimed at improving the material; through the method of Example 1, a symmetric battery that does not need to be in contact with the external environment can be obtained, and the gas generation on the positive electrode side can be analyzed separately. At the same time, the voltage of the single positive electrode side is detected through the three electrodes. The test effect is as shown in the appendix Figure 5 . It can be seen that the gas generated by the positive electrode of this positive electrode material is a large amount of carbon dioxide and a small amount of carbon monoxide.

[0069] Generally speaking, the graph obtained by the EIS test of a conventional battery is as shown in the appendix Figure 7For the graph line shown by WE-CE, the impedance spectrum obtained from actual tests is the coupling result of the positive / negative electrode impedance spectra and is basically indistinguishable. For example, if a certain side reaction occurs at the negative electrode and causes an increase in the negative electrode impedance, this test can only show that a relatively serious side reaction has occurred in the battery materials, resulting in an increase in the battery impedance, but it cannot directly indicate the occurrence point of the reaction. When conducting a comparative test, for example, if it is desired to show that the increase in impedance is caused by a certain positive electrode, then two tests can be carried out separately, controlling the negative electrode / electrolyte to be of the same type, and then measuring the results. If the results are significantly different, it can be shown that it is the influence of the positive electrode. However, it still cannot be explained whether the reaction occurs at the positive electrode or the negative electrode because there is a crosstalk phenomenon in the battery reactions. For example, the positive electrode induces the occurrence of an oxidation reaction, the reactants reach the negative electrode and are reduced, and the reduction product may be an inert insoluble substance, causing an increase in the negative electrode impedance. Conventional tests can only obtain the influence of the positive electrode, while the three-electrode in Example 2 can obtain the WE-RE graph line, that is, the impedance spectrum of a single positive electrode. The CE-RE graph line in the figure corresponds to the impedance spectrum of a single negative electrode, which can decouple the impedance spectra of the positive and negative electrodes without damaging the battery. For the same two battery tests, Example 2 can obtain more specific information.

[0070] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. For the same or similar parts among the various embodiments, reference can be made to each other.

[0071] The above has introduced in detail a kind of electrochemical cell mold for in-situ gas production detection provided by the present utility model. Specific examples are used herein to elaborate on the principle and implementation manner of the present utility model. The description of the above embodiments is only used to help understand the method and its core idea of the present utility model. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the principle of the present utility model, several improvements and modifications can still be made to the present utility model, and these improvements and modifications also fall within the protection scope of the claims of the present utility model.

Claims

1. An electrochemical cell mold for in-situ gas production detection, characterized in that: include: Mould base (4); A movable rod (9) rotatably disposed on the mold base (4); A diaphragm bag (5) is fixedly connected to the movable rod (9), wherein a pole piece (2) with a first pole lug (3) is arranged in the diaphragm bag (5), and the movable rod (9) can realize the reeling of the diaphragm bag (5) by rotating; A diaphragm (7) is arranged on the mold base (4), a positive electrode sheet and a negative electrode sheet are respectively arranged on both sides of the diaphragm (7), and a third electrode tab (1) is arranged on each of the positive electrode sheet and the negative electrode sheet; A mold upper shell (12), arranged on the mold base (4); A pressure component (13) is arranged on the mold upper shell (12), and the pressure component (13) is used to pressurize the positive electrode sheet, the negative electrode sheet, and the electrode sheet (2); A plurality of metal rods (10) are provided, and the plurality of metal rods (10) are movably arranged on the mold upper shell (12), and the metal rods (10) are used to form a conductive path when they abut against the first electrode lug (3) and the third electrode lug (1); A flexible sensor (16) is provided on the pressure component (13) and is used to detect the pressure output by the pressure component (13).

2. The electrochemical cell mold for in-situ gas generation detection according to claim 1, characterized in that: A passage (6) is provided on the side of the mold base (4) and the mold upper shell (12), the passage (6) being used to achieve gas circulation, and a porous separation membrane is provided in the passage (6) for preventing some electrolyte molecules from passing through.

3. The electrochemical cell mold for in-situ gas generation detection according to claim 2, characterized in that: The pressure assembly (13) is provided with a first sealing member (14) and a second sealing member (15), and the first sealing member (14) and the second sealing member (15) are used in conjunction with each other to isolate the internal environment of the mold from the external environment.

4. The electrochemical cell mold for in-situ gas generation detection according to claim 3, characterized in that: It also comprises fixing rods (8), at least three of which are provided, the fixing rods (8) being fixed to the mould base (4), the two ends of the diaphragm (7) being respectively connected to the two fixing rods (8), and the diaphragm bag (5) being arranged between the curved diaphragms (7).

5. The electrochemical cell mold for in-situ gas generation detection according to claim 1, characterized in that: A second pole lug (17) is provided between the diaphragms (7) and on the side corresponding to the positive electrode sheet.

6. The electrochemical cell mold for in-situ gas generation detection according to claim 1, characterized in that: The mold base (4) is provided with a plurality of fixing holes, and the mold upper shell (12) is provided with a plurality of fixing components (11) corresponding to the fixing holes.

7. The electrochemical cell mold for in-situ gas generation detection according to claim 2, characterized in that: The invention also comprises a control system, the control system being connected to the passage (6) and being used to control the degree of opening of the passage (6); the metal rod (10) being used to be connected to a detection fixture; the flexible sensor (16) being used to receive a pressure signal from the pressure component (13); and the control system adjusting the pressure component (13) to output a preset pressure according to the detection result.

8. The electrochemical cell mold for in-situ gas generation detection according to claim 1, characterized in that: The positive electrode sheet is placed on the mold base (4), a first active material layer is provided between the positive electrode sheet and the diaphragm (7), the negative electrode sheet is placed between the diaphragm (7) and the mold upper shell (12), a second active material layer is provided between the negative electrode sheet and the diaphragm (7), and a third active material layer is provided on both sides of the electrode sheet (2) in the diaphragm bag (5).

9. The electrochemical cell mold for in-situ gas generation detection according to any one of claims 1 to 8, characterized in that: The mold upper shell (12) is provided with an adapter (18), the adapter (18) being used to connect to a computer, the control system being connected to the adapter (18), and the flexible sensor (16) being connected to the adapter (18).

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