Electrochemical in-situ XRD battery assembly with controllable atmosphere

Abstract

The invention relates to an atmosphere-controllable electrochemical in-situ XRD (X-Ray Diffraction) battery assembly, which comprises a battery top cover, a main body and a bottom surface assembly, the battery can be embedded into an objective table of an XRD diffractometer. Wherein the battery main body is provided with a gas inlet channel and a gas outlet channel which are internally communicated. In the battery reaction cavity, the electrode on one side can be communicated with the battery bottom cover through the conductive spring, the electrode on the other side is communicated with the battery main body, and the battery main body and the bottom cover need to be insulated. And the macromolecular hemispherical window is arranged in the center of the metal top cover. The electrochemical XRD in-situ test device is easy and convenient to install and suitable for various electrochemical XRD in-situ tests needing atmosphere control.

Description

Technical Field

[0001] The invention relates to a reaction device, in particular to an atmosphere-controllable electrochemical in-situ XRD battery assembly. Background Art

[0002] The whole process of electrochemical in-situ XRD testing is a continuous test of the same material at the same location under different electrochemical states. A large amount of comparative information can be obtained by time correspondence with the electrochemical test curve. The information on sample structure changes obtained through electrochemical in-situ XRD technology can intuitively and deeply understand the solid phase material evolution process of the test electrode during the charge and discharge process of the material, which is of great significance for revealing the mass-charge transfer mechanism of the electrochemical process and the optimization direction of electrode materials.

[0003] The atmosphere of electrochemical reactions is extremely important for the conduct of chemical reactions. Different atmospheres can affect the speed of reactions, reaction products, and even determine whether the chemical reaction can continue. By regulating the environmental atmosphere, we can better understand and predict the rate, reaction route, and reaction products of chemical reactions, and it also helps us to have a deeper understanding of the general laws of material changes involved in chemical reactions.

[0004] Traditional in-situ XRD testing is difficult to achieve real-time and precise control of the ambient atmosphere required for battery reactions, and the device is complex. Therefore, it is critical to design a battery solution that is simple in structure, easy to install, and can control the reaction environment atmosphere in real time. Summary of the invention

[0005] The invention aims to provide an atmosphere-controllable electrochemical in-situ XRD battery assembly, which can realize stable environmental atmosphere regulation during the battery reaction process and is easy to install and operate.

[0006] The technical solution adopted by the present invention is: an atmosphere-controllable electrochemical in-situ XRD battery assembly, the battery assembly comprising: a main body, an upper cover, a polymer spherical cover, and a base, wherein the base, the main body, and the cover are stacked in sequence;

[0007] The base is provided with a circle of screw through holes, through which screws for fixing the base and the main body pass; an annular planar rubber pad is provided on the upper surface of the base, and a screw through hole is opened on the planar rubber pad, which overlaps with the screw through hole on the base; the center of the annular planar rubber pad overlaps with the center of the base; a groove is provided at the center of the base for placing a conductive spring, and an electrode tray is provided on the conductive spring; a negative electrode connector is provided on the side of the base;

[0008] The upper and lower surfaces of the main body are provided with a circle of threaded holes, the threaded holes on the lower surface correspond to the screw through holes on the base one by one, and an insulating lining is provided; a circular groove is provided on the lower surface at the center of the main body, and a circular boss is provided on the upper surface, and a window is provided on the boss to communicate with the circular groove on the lower surface; an annular insulating inner sleeve is provided on the inner wall of the circular groove on the lower surface, and the annular insulating inner sleeve separates the side wall of the electrode tray from the inner wall of the main body; when the main body is installed on the base, the annular insulating inner sleeve is located in the circular groove on the lower surface of the main body, and the electrode tray is located in the annular insulating inner sleeve Inside the bushing, the upper surface of the electrode tray is stacked with a counter electrode, a diaphragm, and an electrode to be tested in sequence from bottom to top, and the electrode tray is supported by a conductive spring so that the electrode to be tested is close to the main body; an annular groove is arranged on the upper surface of the main body, and the center of the annular groove coincides with the center of the main body; an insulating rubber ring is placed in the annular groove; an air inlet channel and an air outlet channel are opened inside the main body, the air inlet of the air inlet channel is outside the circle of the annular groove, and the air outlet is inside the circle of the annular groove; the air inlet of the air outlet channel is inside the circle of the annular groove, and the air outlet is outside the circle of the annular groove; a positive electrode connector is arranged on the side wall of the main body;

[0009] The polymer spherical window is a hemispherical shell as a whole, and its circular edge portion extends outward to form an eaves-like annular plane;

[0010] The cover body is annular, and the central hollow part of the cover body is just embedded in the hemispherical shell of the polymer spherical window from bottom to top; the eaves-like annular plane of the polymer spherical window is located between the cover body and the main body, and is located on the insulating rubber ring of the main body; a circle of screw through holes is opened on the cover body, which corresponds one by one to the threaded holes on the upper surface of the main body.

[0011] Furthermore, the air inlet of the air inlet channel of the main body and the air outlet of the air outlet channel are protruded from the upper surface of the main body; and the cover body is provided with notches corresponding to the two protrusions.

[0012] Furthermore, the electrode tray includes an upper part and a lower part, the upper part is a disc, and the lower part is a cylinder. The diameter of the lower cylinder is smaller than the diameter of the upper disc. The diameter of the lower part is the same as the conductive spring, and the diameter of the upper part is the same as the inner diameter of the annular insulating inner sleeve.

[0013] Furthermore, the central protrusion on the upper surface of the main body is circular, and the window thereon is square or circular.

[0014] Furthermore, the main body, upper cover and base are made of 316L stainless steel, the polymer spherical window is made of PEEK or PET polyester, and the annular flat rubber pad and insulating rubber ring are made of flexible corrosion-resistant rubber material.

[0015] Furthermore, an insulating rubber ring is arranged at the circular opening on the lower surface of the main body, the inner diameter of the insulating rubber ring is the same as the outer diameter of the annular insulating inner bushing, and the outer diameter is smaller than the inner diameter of the plane rubber pad.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] 1) The present invention can realize precise control of the reaction atmosphere through the gas passage, so that the gas can be fully diffused in the specific area of ​​the battery reaction, has high universality, and is highly compatible with the reaction gas / protective gas components required for various battery reactions;

[0018] 2) The present invention has an ingenious design and a simple structure. It can be flexibly customized according to different XRD equipment, and is compatible with other testing equipment and kits such as online mass spectrometers and high and low temperature sample stages, and can realize battery testing under multi-dimensional complex working conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is an atmosphere-controllable electrochemical in-situ XRD cell assembly of the present invention.

[0020] Figure 2 Stereoscopic view of the structure of the atmosphere-controlled electrochemical in-situ XRD cell assembly from a top-down perspective.

[0021] Figure 3 Front view of the atmosphere-controlled electrochemical in-situ XRD cell assembly.

[0022] Figure 4 Cross-sectional view of an electrochemical in-situ XRD cell assembly with controlled atmosphere.

[0023] Figure 5 This is the in-situ XRD test charge and discharge curve and in-situ XRD spectrum of the carbon positive electrode in oxygen atmosphere.

[0024] 1. Screws, 2. Upper cover, 3. Screw holes, 4. Hollow parts of upper cover, 5. Polymer spherical windows, 6. Main body, 7. Insulating rubber ring, 8. Middle reaction chamber, 9. Positive electrode connector, 10. Gas reactant inlet channel, 11. Screw holes, 12. Connecting structure, 13. Insulating rubber ring, 14. Insulating inner sleeve, 15. Electrode tray, 16. Conductive spring, 17. Base, 18. Negative electrode connector, 19. Screw holes, 20. Flat rubber pad, 21. Fixing bolts. DETAILED DESCRIPTION

[0025] The present invention specifically relates to an atmosphere-controllable electrochemical in-situ XRD cell assembly, wherein the core assembly comprises a lower metal base plate, a main body and a corresponding cover assembly.

[0026] An electrochemical in-situ XRD battery assembly with controllable atmosphere, wherein the battery base can be embedded on the stage of an X-ray diffractometer, and the outer wall is provided with a negative electrode connector; the battery body is arranged on the battery base, the middle cavity is the battery reaction site, the body is provided with a gas inlet channel and an outlet channel, and the connecting structure of the channel can realize the stable circulation of a specific atmosphere; the cover body assembly comprises a polymer spherical window and a reaction cell cover, the polymer spherical window is arranged on the battery body, and forms a closed air chamber with the battery cavity; the reaction cell cover is arranged on the polymer spherical window, and can realize effective sealing between the polymer spherical window and the battery body after being installed with locking screws; the present invention realizes precise control of the battery reaction atmosphere through the air path design of air inlet-cavity-air outlet; the battery base is provided with a screw through hole, and a groove for fixing a spring is provided in the middle; the battery body reaction site, From top to bottom, they are the positive electrode sheet, the diaphragm, and the negative electrode sheet; the battery electrode sheet can be fixed to the reaction chamber in the middle of the battery; the inner wall of the battery reaction chamber is provided with an insulating lining; the battery body is provided with a positive electrode connector at the bottom; the battery body also includes a screw through hole on the lower surface, which can be connected to the battery base by bolts, and an insulating sealing ring is provided at the bottom of the battery body and the battery base; the battery body also includes a screw through hole on the upper surface, which can be connected to the battery cover by bolts; the inner diameter of the circular ring of the battery cover is the same as the diameter of the polymer hemispherical window; the middle part of the polymer hemispherical window is hollowed out, and the bottom edge part extends outward, which can be embedded on the battery body and realize edge air sealing; the main body is made of good metal conductors such as stainless steel; the material of the polymer hemispherical window is PEEK or PET with good X-ray transmittance; the sealing ring is an inert rubber sealing ring;

[0027] like Figure 1 The present invention shows an atmosphere-controllable electrochemical in-situ XRD cell assembly, wherein the base (17) can be embedded in the stage of an X-ray diffractometer, the outer wall of the cell is provided with an electrode connection pin hole (18), and the threaded hole (19) connected to the upper assembly is provided with an insulating lining (20);

[0028] The main body (6) can be connected to the lower base (17) by screws, and the insulating lining of the screw hole and the flat rubber pad (20) ensure that the upper and lower electrodes do not short-circuit. The middle reaction chamber includes a spring metal electrode liner and an insulating liner (14), which can achieve close contact between the battery's two poles and the diaphragm under non-short-circuit conditions. The surface of the main body is provided with a gas inlet channel (10) and an outlet channel (12), and the gas enters the internal cavity of the battery through the interface to form a specific atmosphere.

[0029] The cover assembly comprises a polymer hemispherical window (5), a metal battery cover (2) and a polymer elastic seal. The polymer hemispherical window (5) is made of a polymer hard or elastic material and can be fixed on the main body (6); the metal battery upper cover (2) is arranged on the polymer hemispherical window (5) and is tightly spliced ​​by screws (1).

[0030] The main body (6) includes a gas reactant inlet channel and an outlet channel. The gas can enter the connecting structure through the inlet and form a specific circulation atmosphere in the battery cavity through the outlet channel. The screw through hole (19) in the lower metal electrode has an insulating layer, and the central slot can be used to fix the conductive spring (16) required for the internal electrode tray. The battery reaction cavity is composed of the electrode to be tested, the diaphragm, and the counter electrode from top to bottom. The counter electrode is in close contact with the diaphragm and the electrode to be tested through the electrode tray (15) compressed by the spring inside. The upper body and the lower metal electrode of the battery are both provided with electrode wiring pin holes for connecting electrochemical tests. The upper body also includes a screw through hole, which can be connected to the battery base by bolts, and the metal contact areas of the two poles of the battery are designed with insulating components and airtight components. The upper surface of the upper body is provided with a screw blind hole (11), which can be connected to the annular reaction tank cover by bolts. The connection between the upper cover and the main body must meet the airtightness requirements. The annular reaction pool cover (2) has an inner diameter that is equivalent to the diameter of the polymer spherical window (5), and can achieve good sealing performance through a polymer flexible gasket. The polymer spherical window (5) is hemispherical, hollow in the middle, and the bottom edge portion extends outward to form an eaves-like annular plane, which can be nested on the upper surface of the gas electrode to achieve efficient gas sealing. The main body of the kit is made of corrosion-resistant metal materials such as 316L stainless steel; the material of the polymer spherical window (5) is an X-ray transparent material such as PEEK or PET polyester; the polymer airtight materials are all flexible corrosion-resistant rubber materials.

[0031] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments;

[0032] Embodiment 1;

[0033] See also Figure 1 The battery height and radius are customized based on the stage size of the Bruker D2 XRD diffractometer.

[0034] See also Figure 1 , using 316 stainless steel as the material, the battery metal top cover, ventilation body and metal bottom plate are processed respectively.

[0035] See also Figure 1 , a hemispherical gas chamber with a sealed edge is processed using PEEK plastic.

[0036] See also Figure 1An O-ring is placed in the middle of the U-shaped air guide hole.

[0037] See also Figure 1 , an insulating lining is added to the screw hole at the bottom of the battery, and a low-poundage thin spring is configured in the central bottom groove.

[0038] Take the in-situ XRD detection of charge and discharge of neutral zinc-air secondary batteries in oxygen as an example:

[0039] The neutral aqueous zinc-air battery to be tested was installed in the reaction chamber and placed on the XRD stage. Specifically, from top to bottom, there were a carbon positive electrode, a glass fiber separator and a metal zinc sheet negative electrode. About 200 μL of zinc acetate electrolyte was added to the separator.

[0040] Pure oxygen is connected to the battery to be tested through a hose via a mass flow meter, and the gas flow rate is set to 1 mL / min.

[0041] Adjust the stage to the test height, connect the positive and negative electrodes of the battery to the two poles of the charge and discharge tester. Set the current to 0.2mA, and set the charge and discharge program to stand for 4 hours, discharge for 10 hours, and then charge for 10 hours.

[0042] The XRD test program was set to continuous testing, with an angle of 2θ = 5-40°, a scanning interval of 0.1°, and a total of 220 cycles.

[0043] After the gas path is stable, the electrochemical test and XRD scanning are started at the same time. The experiment is stopped after 24 hours. The data results are shown in the figure. Figure 5 .

Claims

1. An atmosphere-controlled electrochemical in-situ XRD cell assembly, the cell assembly comprising: A main body, an upper cover, a polymer spherical cover, and a base, wherein the base, the main body, and the cover are stacked in sequence; The base is provided with a circle of screw through holes, through which screws for fixing the base and the main body pass; an annular planar rubber pad is provided on the upper surface of the base, and a screw through hole is opened on the planar rubber pad, which overlaps with the screw through hole on the base; the center of the annular planar rubber pad overlaps with the center of the base; a groove is provided at the center of the base for placing a conductive spring, and an electrode tray is provided on the conductive spring; a negative electrode connector is provided on the side of the base; The upper and lower surfaces of the main body are provided with a circle of threaded holes, the threaded holes on the lower surface correspond to the screw through holes on the base one by one, and an insulating lining is provided; a circular groove is provided on the lower surface at the center of the main body, and a circular boss is provided on the upper surface, and a window is provided on the boss to communicate with the circular groove on the lower surface; an annular insulating inner sleeve is provided on the inner wall of the circular groove on the lower surface, and the annular insulating inner sleeve separates the side wall of the electrode tray from the inner wall of the main body; when the main body is installed on the base, the annular insulating inner sleeve is located in the circular groove on the lower surface of the main body, and the electrode tray is located in the annular insulating inner sleeve Inside the bushing, the upper surface of the electrode tray is stacked with a counter electrode, a diaphragm, and an electrode to be tested in sequence from bottom to top, and the electrode tray is supported by a conductive spring so that the electrode to be tested is close to the main body; an annular groove is arranged on the upper surface of the main body, and the center of the annular groove coincides with the center of the main body; an insulating rubber ring is placed in the annular groove; an air inlet channel and an air outlet channel are opened inside the main body, the air inlet of the air inlet channel is outside the circle of the annular groove, and the air outlet is inside the circle of the annular groove; the air inlet of the air outlet channel is inside the circle of the annular groove, and the air outlet is outside the circle of the annular groove; a positive electrode connector is arranged on the side wall of the main body; The polymer spherical window is a rigid or flexible hemispherical shell with a low X-ray blocking rate, and its circular edge portion extends outward to form an eaves-like annular plane; The cover body is annular, and the central hollow part of the cover body is just embedded in the hemispherical shell of the polymer spherical window from bottom to top; the eaves-like annular plane of the polymer spherical window is located between the cover body and the main body, and is located on the insulating rubber ring of the main body; a circle of screw through holes is opened on the cover body, which corresponds one by one to the threaded holes on the upper surface of the main body.

2. An atmosphere-controlled electrochemical in-situ XRD cell assembly as claimed in claim 1, characterized in that: The air inlet of the air inlet channel of the main body and the air outlet of the air outlet channel are protruded from the upper surface of the main body; and the cover body is provided with notches corresponding to the two protrusions.

3. An atmosphere-controlled electrochemical in-situ XRD cell assembly as claimed in claim 1, characterized in that: The electrode tray comprises an upper part and a lower part, the upper part is a disc and the lower part is a cylinder, the diameter of the lower cylinder is smaller than the diameter of the upper disc, the diameter of the lower part is the same as the conductive spring, and the diameter of the upper part is the same as the inner diameter of the annular insulating inner sleeve.

4. The atmosphere-controlled electrochemical in-situ XRD cell assembly according to claim 1, characterized in that: The central protrusion on the upper surface of the main body is circular, and the window opened thereon is square or circular.

5. The atmosphere-controlled electrochemical in-situ XRD cell assembly according to claim 1, characterized in that: The main body, upper cover and base are made of 316L stainless steel, the polymer spherical window is made of PEEK or PET polyester, and the annular flat rubber pad and insulating rubber ring are made of flexible corrosion-resistant rubber material.

6. The atmosphere-controlled electrochemical in-situ XRD cell assembly according to claim 1, characterized in that: An insulating rubber ring is arranged at the circular opening on the lower surface of the main body. The inner diameter of the insulating rubber ring is the same as the outer diameter of the annular insulating inner bushing, and the outer diameter is smaller than the inner diameter of the plane rubber pad.

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