In-situ neutron electrochemical test device with low air scattering background

Abstract

The application relates to the technical field of in-situ neutron electrochemical testing, and discloses a low-air-scattering-background in-situ neutron electrochemical testing device; the device comprises a sample cavity connecting flange, a transition cavity flange, a transition cavity, a neutron beam window, a linear manual lifting module and a handheld sample rod; the transition cavity flange and the like form a cavity connected with the sample cavity to maintain vacuum and reduce the influence of air scattering; the transition cavity is designed in multiple stages, the upper end is made of stainless steel, the lower end is provided with a special material neutron beam window, and the vacuum and neutron penetration are considered; the handheld sample rod is provided with a clamping hook to realize quick non-contact disassembly and guarantee safety; the hollow design is provided with a wire slot, wiring is neat, the linear manual lifting module guarantees the accuracy of the sample position, the upper loading mode improves the disassembly and assembly efficiency and reduces stray signals; the application can effectively improve the quality of testing data and is suitable for commercial battery failure mechanism research and the like.

Description

Technical Field

[0001] This invention relates to the field of in-situ neutron electrochemical testing technology, specifically to an in-situ neutron electrochemical testing device with low air scattering background, used to monitor the evolution of material structure in real time under operating conditions, and is particularly suitable for research on failure mechanisms of commercial batteries and related fields. Background Technology

[0002] In the fields of materials science and electrochemistry research, in-situ neutron electrochemical testing technology is of great significance. It can monitor the evolution of material structure in real time under operating conditions, providing key information for the study of failure mechanisms in commercial batteries and helping to develop more efficient and safer battery systems.

[0003] Neutrons have high penetrability and can penetrate deep into the battery; they are sensitive to light elements such as lithium (Li) and oxygen (O), and can accurately monitor the insertion and extraction of lithium; they can also distinguish neighboring transition metals such as nickel (Ni), cobalt (Co), and manganese (Mn), which helps to analyze the distribution and changes of elements in battery materials, thereby allowing for in-depth research into the battery charging and discharging mechanism and the causes of failure.

[0004] The in-situ neutron electrochemical testing system consists of an electrochemical testing device and a sample clamping and positioning device. The electrochemical testing device is used to monitor the electrochemical performance parameters of the battery, such as voltage, current, and capacity; the sample clamping and positioning device is responsible for fixing the sample and ensuring its accurate position in the neutron beam to obtain precise test data.

[0005] However, existing in-situ neutron electrochemical tests are typically conducted in an atmospheric environment, meaning there is no vacuum between the sample and the detector. In this environment, neutrons interact with the air, causing scattering and creating additional background signals. Although this signal does not alter the sample's structural information, it interferes with the detection and analysis of the sample's true structural signals, severely impacting data quality. Especially when analyzing subtle structural changes such as the dynamic evolution of antisite defects and lithium-ion migration in lithium-ion batteries, air scattering signals may obscure crucial information, leading to biased judgments about battery failure mechanisms. Existing testing devices lack effective means to reduce air scattering, making it difficult to meet the demands for high-precision, high-accuracy test data. Therefore, developing an in-situ neutron electrochemical testing device that can reduce air scattering background is urgently needed. Summary of the Invention

[0006] In view of the lack of effective means to reduce the impact of air scattering on data quality in existing testing devices, which fails to meet the demand for high-precision and high-accuracy test data, this invention aims to provide an in-situ neutron electrochemical testing device that can reduce air scattering background to solve the above-mentioned technical problems.

[0007] The technical solution adopted in this invention is: an in-situ neutron electrochemical testing device with low air scattering background, comprising: a sample chamber connecting flange for connecting to the sample chamber of a neutron spectrometer; a transition chamber flange installed on the sample chamber connecting flange; a transition chamber connected below the transition chamber flange; a neutron beam window disposed at the lower part of the transition chamber; a linear manual lifting module fixed on the transition chamber flange; and a portable sample rod connected to the linear manual lifting module, with the sample fixed at the lower end of the portable sample rod; wherein the transition chamber flange, the transition chamber, and the neutron beam window form a complete cavity, which is connected to the sample chamber through the sample chamber connecting flange to maintain the vacuum state of the sample chamber and reduce the impact of air scattering on data quality.

[0008] The transition cavity adopts a multi-stage design, with the upper end made of stainless steel and the lower end of a neutron beam window made of a special material that allows neutrons to pass through smoothly.

[0009] The lower end of the portable sample rod features a hook design. The hook engages via a ring at the upper end of the portable sample rod, enabling rapid, non-contact sample removal.

[0010] The portable sample rod is hollow and has built-in wire grooves to meet the wiring requirements of the electrochemical testing device.

[0011] The linear manual lifting module is connected to the portable sample rod via a positioning block to enable the portable sample rod to move up and down, ensuring the accuracy of the test sample position.

[0012] The device uses a top-loading method to reduce stray signal sources in the entire test environment.

[0013] The sample chamber connecting flange is connected to the neutron spectrometer sample chamber in a sealed manner to ensure a vacuum environment in the sample chamber.

[0014] The special material of the neutron beam window is selected based on neutron penetration and sample testing requirements.

[0015] The shape and size of the transition cavity are designed according to the size of the sample and the testing requirements.

[0016] The lifting range and accuracy of the linear manual lifting module are set according to the requirements of the sample testing position.

[0017] The beneficial effects of this invention are: the low air scattering background in-situ neutron electrochemical testing device of this invention has significant advantages over the prior art. This invention employs a unique transition cavity design to isolate the sample from the vacuum sample chamber of the neutron spectrometer, ensuring that the sample chamber remains under vacuum during testing. This drastically reduces the non-vacuum distance between the sample and the detector. This design significantly reduces the impact of air scattering on data quality, providing strong support for accurate data analysis and enabling more precise resolution of key issues such as the dynamic evolution of antisite defects, lithium-ion migration, and structural evolution in lithium-ion batteries.

[0018] The transition cavity of this invention adopts a multi-stage design, with the upper end made of stainless steel and the lower end's neutron beam window made of a special material that allows neutrons to pass through smoothly. This design ensures both a vacuum environment in the sample cavity and the ability of neutrons to penetrate the neutron beam window and reach the sample, meeting the requirements for neutron penetration in in-situ neutron electrochemical testing and achieving the dual goals of maintaining vacuum in the sample cavity and effective neutron penetration.

[0019] In this invention, the lower end of the portable sample rod features a hook design. The hook engages via the ring at the upper end of the sample rod, enabling rapid, non-contact sample removal. This design avoids direct contact between the experimenter and the sample during removal, reducing safety risks and ensuring the safety of the experimenter. Simultaneously, the rapid sample removal reduces sample change waiting time and improves the utilization efficiency of the neutron testing machine.

[0020] The portable sample rod of this invention features a hollow design with built-in cable channels, facilitating the wiring requirements of electrochemical testing devices. This design avoids messy wiring, ensures a clean and tidy testing environment, and reduces the impact of wiring interference on test results.

[0021] To ensure accurate sample positioning and improve test reliability: The linear manual lifting module is fixed to the transition cavity flange and connected to the portable sample rod via a positioning block, enabling the up and down movement of the portable sample rod and thus ensuring the accuracy of the test sample position. Precise sample position control helps improve the reliability and repeatability of test results.

[0022] This invention employs a top-loading method, which not only improves the efficiency of sample assembly and disassembly but also reduces stray signal sources throughout the testing environment. Reduced stray signals help ensure data accuracy, enabling test results to more accurately reflect the actual condition of the sample. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the overall structure of the present invention. Figure 2 This is a cut-through perspective view of the overall structure of the present invention.

[0024] Figure labeling: 1-Sample chamber connection flange, 2-Transition chamber flange, 3-Transition chamber, 4-Neutron beam window, 5-Linear manual lifting module, 6-Handheld sample rod. Detailed Implementation

[0025] The following detailed description of the specific embodiments of the in-situ neutron electrochemical testing device with low air scattering background of the present invention, with reference to the accompanying drawings, illustrates the technical solution of the present invention through a specific example.

[0026] like Figure 1-2 As shown, this embodiment is an in-situ neutron electrochemical testing device with low air scattering background. This embodiment focuses on the sample clamping and position adjustment device and does not involve the electrochemical testing device.

[0027] Regarding the overall structure of this device: The low air scattering background in-situ neutron electrochemical testing device in this embodiment is mainly composed of sample chamber connecting flange 1, transition chamber flange 2, transition chamber 3, neutron beam window 4, linear manual lifting module 5, and handheld sample rod 6. These components work together to reduce air scattering and achieve accurate testing.

[0028] The structure and connection relationship of each component in this embodiment are as follows: Sample chamber connection flange 1: Sample chamber connection flange 1 is mainly used to connect to the neutron spectrometer sample chamber, realizing the positioning function of this device. It adopts a sealed connection with the neutron spectrometer sample chamber, for example, by sealing elements such as sealing rings to ensure the sealing of the connection, so as to maintain the vacuum environment of the sample chamber.

[0029] Transition cavity flange 2: Transition cavity flange 2 is installed on sample cavity connecting flange 1, and is connected to transition cavity 3 below it. Transition cavity flange 2 serves to connect and seal the transition, ensuring airtightness from sample cavity connecting flange 1 to transition cavity 3.

[0030] Transition Chamber 3: Transition Chamber 3 is connected below Transition Chamber Flange 2. Transition Chamber 3 adopts a multi-stage design, specifically consisting of a transition chamber cylinder and a neutron beam window. The transition chamber cylinder is made of stainless steel, which possesses good mechanical strength and sealing properties, and can withstand certain pressure and temperature changes. The wall thickness of the transition chamber cylinder is designed according to the actual working pressure and strength requirements; for example, when the working pressure is 0.1-0.5 MPa, the wall thickness can be designed to be 2-5 mm. The inner diameter of the transition chamber cylinder is designed according to the sample size and testing requirements, generally ranging from 50-200 mm to ensure that the sample can be placed smoothly within it.

[0031] The transition cavity employs a multi-stage design, meaning the inner diameters of the transition cavity cylinder and the neutron beam window differ. The larger inner diameter of the transition cavity cylinder primarily accommodates the sample and provides sufficient operating space; while the relatively smaller inner diameter of the neutron beam window is designed based on the neutron beam size and the sample testing area to ensure accurate neutron irradiation of the sample. This multi-stage design, while meeting testing requirements, necessitates overcoming manufacturing difficulties and meeting material strength requirements. Due to the different inner diameters of the transition cavity cylinder and the neutron beam window, specialized processes, such as precision machining using CNC machining centers, are required during manufacturing to ensure dimensional and fit accuracy of each component. Simultaneously, to guarantee material strength, the transition cavity cylinder is made of stainless steel with a yield strength typically between 200 and 500 MPa, meeting the strength requirements of practical operation.

[0032] The transition cavity shell and the transition cavity neutron beam window are made of different materials, selected based on neutron penetration requirements. For example, certain metals with good overall performance, such as aluminum, offer good machinability and corrosion resistance, while being lightweight for easy welding and installation; or metals with low neutron absorption, such as vanadium, which exhibits low neutron absorption and possesses certain strength and stability. The thickness of the transition cavity neutron beam window is designed according to neutron penetration and sample testing requirements; for example, for aluminum, the thickness can be between 0.1-0.5 mm; for vanadium foil, the thickness can be between 0.2-5 mm. The transition cavity neutron beam window is connected to the transition cavity shell using welding or flange connections to ensure the sealing and stability of the connection.

[0033] Neutron Beam Window 4: Neutron beam window 4 is located at the lower part of transition cavity 3. Its height and position are designed based on the neutron beam center and the solid angle of the detector, simultaneously maintaining the vacuum of the scattering cavity and ensuring the smooth passage of neutrons to interact with the sample. The special material selection of neutron beam window 4 minimizes the impact on neutron propagation while ensuring smooth neutron passage. For example, when aluminum is used as the neutron beam window, its surface undergoes special treatments, such as polishing and anodizing, to increase corrosion resistance and reduce neutron scattering on the surface. The connection between neutron beam window 4 and transition cavity 3 is sealed, such as with sealant, to prevent air leakage into transition cavity 3, thereby maintaining the vacuum state of the sample cavity.

[0034] Linear manual lifting module 5: The linear manual lifting module 5 is fixed on the transition cavity flange 2. It is connected to the portable sample rod 6 via a positioning block, enabling the vertical movement of the portable sample rod 6. The adjustment principle of the linear manual lifting module 5 mainly uses a lead screw and two slide rails for adjustment. The lead screw is usually a trapezoidal lead screw or a ball screw. The trapezoidal lead screw has self-locking properties, ensuring that the portable sample rod 6 stops and remains stable at any position; the ball screw has higher transmission efficiency and accuracy. The two slide rails are installed on both sides of the lead screw, arranged parallel to the lead screw. The portable sample rod 6 is connected to the lead screw and slide rails via the positioning block. When the lead screw is rotated, the positioning block moves up and down along the lead screw and slide rails, thereby driving the portable sample rod 6 to move up and down. The lifting range and accuracy of the linear manual lifting module 5 are set according to the requirements of the sample testing position. For example, the lifting range can be between 10 and 50 cm, and the accuracy can reach the 0.1 mm level to ensure the accuracy of the test sample position. When installing the linear manual lifting module 5, it is necessary to ensure the parallelism and perpendicularity of the lead screw and slide rail to ensure the smooth movement of the handheld sample rod 6.

[0035] Handheld Sample Rod 6: The handheld sample rod 6 connects to the linear manual lifting module 5, and the sample is fixed at the lower end of the handheld sample rod 6. The lower end of the handheld sample rod 6 features a hook design; the hook engages via a ring at the upper end of the handheld sample rod 6, enabling quick, non-contact sample removal and ensuring the safety of laboratory personnel. The handheld sample rod 6 is hollow with built-in wire channels, facilitating the wiring requirements of the electrochemical testing device, ensuring a clean and tidy testing environment, and preventing the influence of messy wiring on test results.

[0036] In this embodiment, during in-situ neutron electrochemical testing, the sample is first fixed to the lower end of the portable sample rod 6, with a hook design at the lower end of the rod ensuring a secure fixation. Then, the height of the portable sample rod 6 is adjusted using the linear manual lifting module 5 to position the sample appropriately, ensuring accurate neutron irradiation.

[0037] In this embodiment, the sample chamber connecting flange 1 is sealed to the neutron spectrometer sample chamber. The transition chamber flange 2, transition chamber 3, and neutron beam window 4 form a complete cavity, which is connected to the sample chamber via the sample chamber connecting flange 1 to maintain the vacuum state of the sample chamber. At this time, the sample is placed in the cavity formed by the transition chamber flange 2, transition chamber 3, and neutron beam window 4. Neutrons enter the cavity through the neutron beam window 4 and interact with the sample, and the generated signal is received by the detector.

[0038] In this embodiment, because the sample chamber is kept under vacuum during testing, the non-vacuum distance between the sample and the detector is significantly reduced, thereby effectively minimizing the impact of air scattering on data quality. After testing, the sample is quickly and non-contactly disassembled by releasing the trigger hook at the upper ring of the portable sample rod 6, ensuring the safety of the experimental personnel.

[0039] The low-air-scattering-background in-situ neutron electrochemical testing apparatus of this embodiment significantly reduces the impact of air scattering on data quality during actual testing, improving the accuracy and reliability of the test data. The multi-stage design of the transition cavity ensures a vacuum in the sample chamber while allowing neutrons to pass smoothly, meeting the requirements of in-situ neutron electrochemical testing. The hook design and hollow wiring design of the portable sample rod ensure both the safety of the experimenters and the cleanliness of the testing environment. The linear manual lifting module ensures the accuracy of the sample position, improving the precision and repeatability of the test.

[0040] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A low-air-scattering-background in-situ neutron electrochemical testing device, characterized in that: include: Sample chamber connection flange (1) is used to connect the neutron spectrometer sample chamber; The transition cavity flange (2) is installed on the sample cavity connecting flange (1); The transition cavity (3) is connected below the transition cavity flange (2); A neutron beam window (4) is disposed in the lower part of the transition cavity (3); A linear manual lifting module (5) is fixed on the transition cavity flange (2); A portable sample rod (6) is connected to the linear manual lifting module (5), and the sample is fixed at the lower end of the portable sample rod (6). The transition cavity flange (2), the transition cavity (3) and the neutron beam window (4) form a complete cavity, which is connected to the sample cavity through the sample cavity connecting flange (1) to maintain the vacuum state of the sample cavity and reduce the impact of air scattering on data quality.

2. The in-situ neutron electrochemical testing device with low air scattering background according to claim 1, characterized in that: The transition cavity (3) adopts a multi-stage design, with the upper end made of stainless steel and the lower end of the neutron beam window (4) made of a special material that allows neutrons to pass through smoothly.

3. The in-situ neutron electrochemical testing device with low air scattering background according to claim 1, characterized in that: The lower end of the portable sample rod (6) is designed with a hook. The hook is engaged by triggering the upper ring of the portable sample rod (6), thereby enabling rapid non-contact disassembly of the sample.

4. The in-situ neutron electrochemical testing device with low air scattering background according to claim 1, characterized in that: The portable sample rod (6) is hollow and has a built-in wire groove to meet the wiring requirements of the electrochemical testing device.

5. The in-situ neutron electrochemical testing device with low air scattering background according to claim 1, characterized in that: The linear manual lifting module (5) is connected to the handheld sample rod (6) via a positioning block to enable the handheld sample rod (6) to move up and down, ensuring the accuracy of the test sample position.

6. The in-situ neutron electrochemical testing device with low air scattering background according to claim 1, characterized in that: The device uses a top-loading method to reduce stray signal sources in the entire test environment.

7. The in-situ neutron electrochemical testing device with low air scattering background according to any one of claims 1-6, characterized in that: The connection between the sample chamber connecting flange (1) and the neutron spectrometer sample chamber is a sealed connection to ensure the vacuum environment of the sample chamber.

8. The in-situ neutron electrochemical testing device with low air scattering background according to any one of claims 1-6, characterized in that: The special material of the neutron beam window (4) is selected according to the neutron penetration and sample testing requirements, and the special material is aluminum.

9. The in-situ neutron electrochemical testing device with low air scattering background according to any one of claims 1-6, characterized in that: The shape and size of the transition cavity (3) are designed according to the size of the sample and the test requirements.

10. The in-situ neutron electrochemical testing device with low air scattering background according to any one of claims 1-6, characterized in that: The lifting range and accuracy of the linear manual lifting module (5) are set according to the requirements of the sample test position.

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