Reaction device and chemical detection system
By introducing a variable-volume container and a solid-liquid isolation component into the reaction device, the problems of increased gas pressure and gas loss in the reaction chamber during the injection of the reaction liquid were solved, achieving constant pressure control and high-accuracy battery detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2026-04-17
AI Technical Summary
Existing technologies cause an increase in gas pressure in the reaction chamber during the injection of reaction liquid into the reactor, leading to operational difficulties and inaccurate test results, which is particularly difficult to apply in the testing of large-capacity batteries.
Design a reaction apparatus comprising a reactor, a variable volume container, and a solid-liquid isolation component. By selectively connecting or isolating the reaction chamber from the variable volume container, and by installing the solid-liquid isolation component within the reaction chamber, the contact time between the reaction liquid and the solid reactants can be controlled to prevent gas loss.
It achieves constant pressure control within the reaction chamber, avoiding pressure increase and gas loss during reaction liquid injection, thus improving detection accuracy and ease of operation. It is suitable for testing lithium-ion and sodium-ion batteries of various capacities.
Smart Images
Figure CN224127241U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of chemical detection, and more particularly to a reaction apparatus and a chemical detection system. Background Technology
[0002] The detection method for inactive lithium or inactive sodium typically involves placing the solid sample to be tested (solid reactant, usually an electrode) in the reaction chamber of a reactor under an inert atmosphere, sealing the reaction chamber, and then injecting the reaction solution into the reaction chamber. The reaction solution reacts with the solid reactant to produce gas. After the reaction is complete, the gas in the reactor is extracted for analysis using gas chromatography or mass spectrometry.
[0003] During the injection of the reaction liquid, the gas pressure in the reaction chamber usually increases. However, in the process of solving the problem of increased gas pressure, the gas production loss during the reaction occurs, resulting in operational difficulties and inaccurate test results. Utility Model Content
[0004] This application is made in view of the above-mentioned technical problems, and its purpose is to solve the problems of rising gas pressure in the reaction chamber and loss of gas production during the process of injecting reaction liquid into the reactor.
[0005] To achieve the above objectives, this application provides a reaction apparatus and a chemical detection system.
[0006] The first aspect of this application provides a reaction apparatus, including a reactor, a variable volume container, and a solid-liquid separation component;
[0007] The reactor is equipped with a liquid inlet and a reaction chamber connected to the liquid inlet; the liquid inlet is used to inject the reaction liquid into the reaction chamber; the reaction chamber is used to contain the reaction liquid and solid reactants.
[0008] The variable-volume container can be selectively connected to or isolated from the reaction chamber;
[0009] A solid-liquid isolation component is installed inside the reaction chamber to isolate the reaction liquid from the solid reactants.
[0010] The reaction apparatus of this application embodiment has the following beneficial effects:
[0011] During the process of adding the reaction liquid into the reaction chamber through the inlet, the connection between the reaction chamber and the variable volume container is controlled so that the gas pressure in the reaction chamber will be transferred to the variable volume container, thereby keeping the reaction chamber at a constant pressure and alleviating the problem of gas pressure increase in the reaction chamber during the injection of the reaction liquid.
[0012] Meanwhile, because the reaction chamber is equipped with a solid-liquid isolation component, the reaction liquid is prevented from contacting the solid reactants placed in the reaction chamber during the injection process, thus preventing a reaction. After the reaction liquid is completely injected, the reaction chamber is isolated from the variable-volume container, and then the solid reactants are brought into contact with the reaction liquid to react and produce gas. This separates the injection time of the reaction liquid from the reaction time, thereby solving the problem of gas loss due to the reaction between the reaction liquid and the solid reactants during injection, which then enters the variable-volume container.
[0013] In summary, by selectively connecting or isolating the reaction chamber from the variable-volume container, and by installing a solid-liquid isolation component within the reaction chamber, the problem of increased pressure in the reaction chamber during the injection of the reaction liquid can be mitigated, and no gas loss occurs.
[0014] In some embodiments, the variable volume container is provided with a variable volume container on / off valve for controlling the connection or isolation between the variable volume container and the outside world.
[0015] To ensure the variable volume container provides space to accommodate the gas expelled from the reaction chamber by the reaction liquid, and to prevent subsequent reaction gases from being contaminated by gases from the variable volume container, the variable volume container can be evacuated before connecting it to the reaction chamber. The vacuum state of the variable volume container can be maintained using its on / off valve.
[0016] In some embodiments, the variable volume container includes one or more of an air bag, a balloon, and a syringe.
[0017] Gas bags, balloons, and syringes can all undergo volume changes under internal pressure or external force. During the injection of the reaction solution into the reaction chamber from the inlet, controlling the connection between the reaction chamber and the gas bag, balloon, or syringe will transfer the gas pressure in the reaction chamber to the gas bag, balloon, or syringe, thus maintaining a constant pressure in the reaction chamber and mitigating the problem of increased gas pressure in the reaction chamber during injection.
[0018] In some embodiments, the total volume of the variable-volume container is greater than or equal to the total volume of the reaction liquid.
[0019] Such a variable-volume container has enough space to accommodate the gas squeezed out of the reaction chamber by the reaction liquid, which can better prevent the gas pressure in the reaction chamber from increasing as the reaction liquid is injected.
[0020] In some embodiments, the solid-liquid isolation component includes a solid reactant support, and a gap is provided between the solid reactant support and the bottom of the reaction chamber;
[0021] The solid reactant support has through holes, and / or there is a gap between the solid reactant support and the side wall of the reaction chamber.
[0022] The solid reactant support can be used to hold solid reactants; the reaction liquid injected from the injection port can reach the bottom of the solid reactant support (bottom of the reaction chamber) through the through holes in the solid reactant support or through the gap between the solid reactant support and the side wall of the reaction chamber. In this way, the reaction liquid can be kept from coming into contact with the solid reactants placed in the reaction chamber during the injection process.
[0023] Furthermore, after the liquid injection is completed and the reaction chamber is isolated from the variable volume container, the reactor can be inverted so that the reaction liquid flows through the through holes in the solid reactant support or the gap between the solid reactant support and the side wall of the reaction chamber to the solid reactant side, and reacts with the solid reactant.
[0024] This allows the injection time of the reaction solution to be separated from the reaction time, thereby solving the problem of gas loss when the reaction solution reacts with the solid reactants during the injection process and the gas enters the variable volume container.
[0025] In some embodiments, the distance between the solid reactant support and the bottom of the reaction chamber is greater than the height of the reaction liquid within the reaction chamber. This prevents the solid reactant from contacting the reaction liquid during the injection process.
[0026] In some embodiments, the solid-liquid isolation component further includes a support body disposed within the reaction chamber, and a solid reactant support body disposed on the support body.
[0027] The support can be one or more of a support column or frame, used to support the solid reactant support and create a gap between the solid reactant support and the bottom of the reaction chamber. The support can be fixed at any position inside the reaction chamber (e.g., at the bottom), or it can be placed at the bottom of the reaction chamber without being fixed.
[0028] In some embodiments, a solid reactant support is fixedly disposed on the side wall of the reaction chamber.
[0029] For example, the solid reactant support can be fixed to the side wall of the reaction chamber by bonding, welding, or other methods. This allows the solid reactant support to be fixed without the need for a separate support structure, and creates a gap between the solid reactant support and the bottom of the reaction chamber.
[0030] In some embodiments, the solid-liquid isolation component includes a reaction liquid buffer container.
[0031] During the reaction liquid injection process, the solid reactants are placed in the space inside the reaction chamber and outside the reaction liquid buffer container, and the reaction liquid is injected into the reaction liquid buffer container, so that the reaction liquid does not come into contact with the solid reactants during the injection process.
[0032] In some embodiments, the total volume of the reaction buffer container is greater than or equal to the total volume of the reaction liquid. This allows the reaction liquid to be completely contained without overflow, preventing solid reactants from coming into contact with the reaction liquid during the injection process.
[0033] In some embodiments, the reactor further includes a liquid guide pipe, one end of which is connected to the liquid inlet and the other end is located inside the reaction chamber;
[0034] The liquid guide tube passes through the through hole on the solid reactant support, or passes through the gap between the solid reactant support and the side wall of the reaction chamber, or is positioned above the reaction liquid buffer container, or extends into the reaction liquid buffer container.
[0035] During the injection of the reaction solution, the reaction solution can be guided by the liquid guide tube to the bottom of the solid reactant support, or into the reaction solution buffer container, so as not to come into contact with the solid reactants placed in the reaction chamber.
[0036] In some embodiments, the solid reactant includes an electrode.
[0037] The reaction apparatus of this application embodiment can be used to perform inactive lithium titration reactions on lithium-ion batteries of various capacities, or to perform inactive sodium titration reactions on sodium-ion batteries of various capacities. In this case, the solid reactant is typically an electrode.
[0038] A second aspect of this application provides a chemical detection system, including the above-described reaction apparatus.
[0039] The aforementioned reaction apparatus can be integrated into a chemical detection system for automatic or manual detection. For example, automatic sampling can be achieved by connecting an automatic sampling unit to the sampling port of the reaction apparatus. Simultaneously, the automatic sampling unit can be connected to an automatic sample delivery unit, which delivers the gas sample extracted by the automatic sampling unit to the detection equipment (e.g., chromatograph, mass spectrometer) for analysis. Alternatively, the reaction apparatus can be connected to an automatic liquid injection device to automatically add reaction solution to the apparatus. Using this chemical detection system, the operational resistance during the detection process is low, and the detection results have high accuracy.
[0040] In some embodiments, the chemical detection system includes one or more of an inactive lithium detection system and an inactive sodium detection system.
[0041] This chemical detection system can be used to detect inactive lithium in lithium-ion batteries and / or inactive sodium in sodium-ion batteries. The lithium-ion or sodium-ion batteries can be small-capacity batteries (e.g., batteries with a capacity less than 1000mAh, such as 50mAh to 100mAh) or large-capacity batteries (e.g., batteries with a capacity greater than 1000mAh, such as 1000mAh to 6500mAh, or even larger). The chemical detection system in this application, including the aforementioned reaction apparatus, can detect batteries of various capacities and is expected to be widely used in practical battery testing. Attached Figure Description
[0042] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0043] Figure 1 This is a schematic diagram of the reaction apparatus provided in Embodiment 1 of this application;
[0044] Figure 2 This is a schematic diagram of the sample holder provided in Embodiment 1 of this application;
[0045] Figure 3 This is a schematic diagram of the reaction apparatus provided in Embodiment 2 of this application.
[0046] Figure label:
[0047] 100-Reactor, 101-Cup body, 102-Lid body, 103-Liquid guide tube, 104-Sampling port, 105-First two-way valve, 106-Sealing cap, 107-Second two-way valve;
[0048] 200-Air bag, 201-Rotary switch valve, 202-Air hose;
[0049] 300-Sample rack, 301-Frame, 302-Solid reactant support, 303-Through hole, 300a-Buffer bottle;
[0050] 400 - Sample, 500 - Injector, 600 - Airtight gas extraction needle. Detailed Implementation
[0051] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.
[0052] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.
[0053] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.
[0054] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
[0055] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.
[0056] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple groups" refers to two or more (including two groups), and "multiple pieces" refers to two or more (including two pieces).
[0057] In the description of the embodiments of this application, the technical terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.
[0058] In the description of the embodiments of this application, unless otherwise expressly specified and limited, technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.
[0059] Quantitative detection of inactive lithium or sodium in electrodes can provide a deep understanding of the electrode's microstructure, offering crucial theoretical support for battery research and optimization. Titration, currently an effective method for quantitative detection of inactive lithium or sodium, typically utilizes the mechanism by which inactive lithium or sodium react with a reaction solution to generate different gases, thereby distinguishing (qualitatively) and quantifying (quantitatively) the individual inactive lithium or sodium particles on the electrode.
[0060] Typically, in the detection of inactive lithium or inactive sodium, the solid sample to be tested (i.e., the solid reactant, usually an electrode) is first placed in the reaction chamber of the reactor under an inert atmosphere. The reactor is then sealed, and the reaction solution is added to the reactor through a syringe, injection tube, or other means. The reaction solution reacts with the solid reactant to produce gas. After the reaction is complete, the gas in the reactor is extracted for analysis using gas chromatography or mass spectrometry.
[0061] Because the reaction chamber involved in the detection method is a constant-volume chamber, its total volume remains constant during the injection of the reaction liquid. As the reaction liquid is injected, the gas pressure within the chamber continuously increases. The more reaction liquid injected, the higher the gas pressure, leading to various problems. For example, subsequent injections of the reaction liquid may be difficult. Furthermore, at the moment the injection is complete, the gas pressure inside the reaction chamber may exceed the atmospheric pressure outside. Gas inside the chamber may escape through the injection tube connected to the atmosphere at this instant; however, the reaction has already been underway for some time, so the escaping gas will contain some of the reaction products, thus affecting the quantitative accuracy of the detection method.
[0062] Therefore, this method is only suitable for titration testing of small-unit electrode samples (especially electrode samples of small-capacity batteries) with low reaction liquid requirements, and it is difficult to apply to the testing of electrode samples of large-capacity batteries with high reaction liquid requirements. The universality of the detection method is low, and it is difficult to apply it on a large scale in actual battery testing.
[0063] To address the issue of increased gas pressure in the reaction chamber during the injection of the reaction solution, it's possible to design the reaction chamber as a constant-pressure chamber rather than a constant-volume chamber. This would prevent the internal gas pressure from increasing with the injection of the reaction solution. A simple and low-cost constant-pressure chamber design involves connecting a variable-volume container to an existing constant-volume chamber. During the injection of the reaction solution, the increased gas pressure within the reaction chamber due to the injection can be transferred to the variable-volume container, thus maintaining a constant pressure inside the reaction chamber.
[0064] Considering gas uniformity and ease of operation, in actual testing, only the gas in the constant-volume reaction chamber is typically sampled for detection. However, during the injection of the reaction liquid, the liquid reacts with the solid reactants placed in the reaction chamber to produce gas. Some of this gas diffuses into the variable-volume container, which is difficult to collect, resulting in gas loss. This gas loss will introduce significant errors into the detection results, leading to low accuracy.
[0065] Based on this, in order to alleviate the problem of increased gas pressure inside the reaction chamber during the injection of the reaction liquid, and to prevent gas loss, this application designs a reaction device by selectively connecting or isolating the reaction chamber of the reactor with a variable volume container, and setting a solid-liquid isolation component in the reaction chamber.
[0066] In this reaction apparatus, because the constant-volume reaction chamber can be connected to the variable-volume container, the gas pressure inside the reaction chamber is transferred to the variable-volume container during the injection of the reaction liquid, thus maintaining a constant pressure inside the reaction chamber. Simultaneously, thanks to the solid-liquid isolation component, the reaction liquid does not come into contact with the solid reactants placed in the reaction chamber during injection, and no reaction occurs. After the reaction liquid is completely injected, the reaction chamber is isolated from the variable-volume container, and then the reaction between the solid reactants and the reaction liquid to produce gas is controlled. This separates the injection time of the reaction liquid from the reaction time, thereby solving the problem of gas loss due to the reaction of the reaction liquid with the solid reactants during injection, which then enters the variable-volume container.
[0067] [Reaction apparatus]
[0068] This application provides a reaction apparatus, including a reactor, a variable volume container, and a solid-liquid separation component;
[0069] The reactor is equipped with a liquid inlet and a reaction chamber connected to the liquid inlet; the liquid inlet is used to inject the reaction liquid into the reaction chamber; the reaction chamber is used to contain the reaction liquid and solid reactants.
[0070] The variable-volume container can be selectively connected to or isolated from the reaction chamber;
[0071] A solid-liquid isolation component is installed inside the reaction chamber to isolate the reaction liquid from the solid reactants.
[0072] The reaction chamber is the hollow part inside the reactor, used to contain the reaction liquid and solid reactants and allow the reaction to take place. A variable-volume container is a container whose volume can change according to internal pressure or external forces.
[0073] Selective connection or isolation between the variable-volume container and the reaction chamber means that the two can be in a connected or isolated state as needed. When the variable-volume container is connected to the reaction chamber, the interior of the container and the interior of the chamber are interconnected, allowing gas flow between them. Conversely, when the container is isolated, the interior of the container and the chamber are not connected, preventing gas flow. This selective connection or isolation is typically achieved using a switching valve. In other words, a switching valve can be installed between the variable-volume container and the reaction chamber to control the connection or isolation between them.
[0074] Solid-liquid isolation components refer to components that have solid-liquid isolation functions.
[0075] The reaction apparatus of this application embodiment has the following beneficial effects:
[0076] During the process of adding the reaction liquid into the reaction chamber through the inlet, the connection between the reaction chamber and the variable volume container is controlled. This transfers the gas pressure inside the reaction chamber to the variable volume container, keeping the pressure inside the reaction chamber constant and thus alleviating the problem of increased gas pressure inside the reaction chamber during the injection of the reaction liquid.
[0077] Meanwhile, because the reaction chamber is equipped with a solid-liquid isolation component, the reaction liquid is prevented from contacting the solid reactants placed inside the chamber during the injection process, thus preventing a reaction. After the reaction liquid is completely injected, the reaction chamber is isolated from the variable-volume container, and then the solid reactants are brought into contact with the reaction liquid to produce gas. This separates the injection time from the reaction time, thereby solving the problem of gas loss due to the reaction between the reaction liquid and the solid reactants during injection, which then enters the variable-volume container.
[0078] In summary, by selectively connecting or isolating the reaction chamber from the variable-volume container, and by installing a solid-liquid isolation component within the reaction chamber, the problem of increased internal pressure during the injection of the reaction liquid can be mitigated, and no gas loss occurs.
[0079] 1. Reactor
[0080] In some embodiments, the reactor can be one or more of a reaction vessel or a reaction kettle. Different instruments can be used as reactors as needed.
[0081] In some embodiments, the reactor includes a reactor body and a reactor cover, the reactor cover being detachably and sealingly disposed on the reactor body; the reactor cover and / or the reactor body are provided with the aforementioned liquid inlet; the reactor body is provided with the aforementioned reaction chamber.
[0082] The reaction chamber within the reactor body is used to contain reactants (e.g., solid reactants, injected reaction liquid). When the reactor is a reaction cup, the reactor body can also be called a cup body; when the reactor is a reaction vessel, the reactor body can also be called a vessel body. The reactor cover is sealed to the reactor body, ensuring a tight seal. Removing the reactor cover from the reactor body allows the reactor to be opened, and solid reactants can be placed into the reaction chamber.
[0083] The inlet is used to inject the reaction liquid. The inlet can be set on the reactor body or the reactor cover alone, or on both the reactor body and the reactor cover, so that it is suitable for injecting one or more reaction liquids.
[0084] Understandably, this inlet is used for injecting the reaction solution. Before and after injection, the inlet must remain sealed to prevent the reaction chamber from communicating with the ambient atmosphere. In practice, a first switching valve can be installed on the inlet to control its opening and closing, thereby enabling or isolating the reaction chamber from the outside environment. A sealing cap can be installed on the first switching valve to improve the airtightness of the injection port. Simultaneously, sealing gaskets can be installed in both the first switching valve and the sealing cap to improve the airtightness between related connecting structures.
[0085] The first switching valve can be a two-way valve.
[0086] In some embodiments, the reactor includes a liquid guide tube, one end of which is connected to the inlet of the reactor, and the other end is located inside the reaction chamber.
[0087] By designing a liquid guide tube, the reaction liquid injected from the injection port can be guided to the desired location.
[0088] In some embodiments, the reactor is provided with a vent that communicates with the reaction chamber. A second switching valve is provided on the vent to control the opening and closing of the vent, thereby enabling the reaction chamber to communicate with or be isolated from the outside environment.
[0089] Understandably, the vent can be provided on the reactor cover or on the reactor body.
[0090] The second switching valve can be a two-way valve.
[0091] In some embodiments, the reactor is provided with a sampling port communicating with the reaction chamber. It is understood that the sampling port can be provided on the reactor cover or on the reactor body.
[0092] After the reaction is complete, the gas in the reaction chamber can be extracted through the sampling port for testing. Understandably, this sampling port is kept sealed for a long period of time and is connected to the sampling instrument (e.g., sampling needle) used for sampling during the sampling process.
[0093] 2. Variable volume container
[0094] In some embodiments, the variable volume container is provided with a variable volume container on / off valve for controlling the connection or isolation between the variable volume container and the outside world. This variable volume container on / off valve may be a rotary valve.
[0095] A variable volume container switching valve is used to control the connection or isolation between the variable volume container and the outside world. Understandably, the outside world here refers to the environment or structure outside the variable volume container, such as the ambient atmosphere or the reactor (more specifically, the reaction chamber).
[0096] To ensure the variable volume container provides space to accommodate the gas expelled from the reaction chamber by the reaction liquid, and to prevent subsequent reaction gases from being contaminated by gases from the variable volume container, the variable volume container can be evacuated before connecting it to the reaction chamber. The vacuum state of the variable volume container can be maintained using its on / off valve.
[0097] In some embodiments, the variable volume container switch valve is connected to the second switch valve on the reactor vent via a gas pipe.
[0098] With both the variable volume container switch valve and the second switch valve open, the variable volume container and the reaction chamber can be connected through the gas pipe to achieve gas flow between them.
[0099] In some embodiments, the variable volume container includes one or more of an air bag, a balloon, and a syringe. Optionally, the variable volume container is an air bag.
[0100] Gas bags, balloons, and syringes can all undergo volume changes under internal pressure or external force. During the injection of the reaction solution into the reaction chamber from the inlet, controlling the connection between the reaction chamber and the gas bag, balloon, or syringe will transfer the internal pressure of the reaction chamber to the gas bag, balloon, or syringe, maintaining a constant pressure inside the reaction chamber and thus mitigating the problem of increased internal pressure during the injection process.
[0101] Considering the ease with which the gas bag can connect to the reaction chamber and the excellent sealing of the connection, the gas bag is a viable option in practice. Furthermore, before connecting the gas bag to the reaction chamber, it can be evacuated to mitigate the problem of increased pressure inside the reaction chamber during liquid injection.
[0102] In some embodiments, the total volume of the variable-volume container is greater than or equal to the total volume of the reaction solution. The total volume of the reaction solution typically refers to the total volume of the reaction solution at the maximum injection rate.
[0103] Such a variable-volume container has enough space to accommodate the gas squeezed out of the reaction chamber by the reaction liquid, which can better prevent the gas pressure inside the reaction chamber from increasing as the reaction liquid is injected.
[0104] 3. Solid-liquid isolation components
[0105] A solid-liquid isolation component is installed inside the reaction chamber to isolate the reaction liquid from the solid reactants.
[0106] In some embodiments, the solid-liquid isolation component includes a solid reactant support, with a gap between the solid reactant support and the bottom of the reaction chamber; the solid reactant support has a through hole, and / or a gap between the solid reactant support and the sidewall of the reaction chamber.
[0107] The solid reactant support can be used to hold solid reactants; the reaction liquid injected from the injection port can reach the bottom of the solid reactant support (bottom of the reaction chamber) through the through-hole in the solid reactant support or through the gap between the solid reactant support and the side wall of the reaction chamber. In this way, the reaction liquid can be kept from coming into contact with the solid reactants placed in the reaction chamber during the injection process.
[0108] Furthermore, after the liquid injection is completed and the second switch valve is closed to isolate the reaction chamber from the variable volume container, the reactor can be inverted so that the reaction liquid flows through the through holes in the solid reactant support or through the gap between the solid reactant support and the side wall of the reaction chamber to the solid reactant side, where it comes into contact with the solid reactant and reacts.
[0109] This allows the injection time of the reaction solution to be separated from the reaction time, thereby solving the problem of gas loss when the reaction solution reacts with the solid reactants during the injection process and the gas enters the variable volume container.
[0110] In some embodiments, the distance between the solid reactant support and the bottom of the reaction chamber is greater than the height of the reaction liquid in the reaction chamber, so that the solid reactant and the reaction liquid do not come into contact during the injection process.
[0111] Understandably, the distance between the solid reactant support and the bottom of the reaction chamber refers to the distance between the lowest point of the solid reactant support and the bottom of the reaction chamber. In some cases, this distance can also be the distance between the through-hole and the bottom of the reaction chamber. The height of the reaction liquid in the reaction chamber usually refers to the horizontal height of the reaction liquid within the reaction chamber at the maximum injection volume.
[0112] In some embodiments, the solid-liquid isolation component further includes a support body disposed within the reaction chamber, and a solid reactant support body disposed on the support body.
[0113] The support can be one or more of a support column or frame, used to support the solid reactant support and create a gap between the solid reactant support and the bottom of the reaction chamber. The support can be fixed at any position inside the reaction chamber (e.g., at the bottom), or it can be placed at the bottom of the reaction chamber without being fixed.
[0114] In some embodiments, a solid reactant support is fixedly disposed on the side wall of the reaction chamber.
[0115] For example, the solid reactant support can be fixed to the side wall of the reactor chamber by bonding, welding, or other methods. This allows the solid reactant support to be fixed without the need for a separate support structure, and creates a gap between the solid reactant support and the bottom of the reaction chamber.
[0116] In some embodiments, the solid-liquid isolation component includes a reaction liquid buffer container disposed within the reaction chamber. Optionally, the reaction liquid buffer container is disposed at the bottom of the reaction chamber.
[0117] During the reaction solution injection process, the solid reactants are placed in the space inside the reaction chamber and outside the reaction solution buffer container. The reaction solution is then injected into the buffer container, ensuring that the reaction solution does not come into contact with the solid reactants during injection. The reaction solution buffer container can be any shape of open bottle (buffer bottle) or cup, such as a beaker.
[0118] In some embodiments, the total volume of the reaction solution buffer container is greater than or equal to the total volume of the reaction solution.
[0119] This allows the reaction liquid to be completely contained without overflowing, preventing solid reactants from coming into contact with the reaction liquid during the injection process.
[0120] In some embodiments, referring to the foregoing, the reactor includes a liquid guide tube, one end of which is connected to the inlet of the reactor, and the other end of which is located inside the reaction chamber.
[0121] Meanwhile, the positional relationship between the liquid guide tube and the solid-liquid isolation component is as follows: the liquid guide tube passes through the through hole on the solid reactant support, or the liquid guide tube passes through the gap between the solid reactant support and the side wall of the reaction chamber, or the liquid guide tube is set above the reaction liquid buffer container, or the liquid guide tube extends into the reaction liquid buffer container.
[0122] In this way, during the injection of the reaction solution, the reaction solution can be guided by the liquid guide tube to the bottom of the solid reactant support, or into the reaction solution buffer container, without coming into contact with the solid reactants placed in the reaction chamber.
[0123] 4. Use of the reaction apparatus
[0124] The reaction apparatus of this application embodiment can be applied to various solid-liquid reactions that generate gases, exhibiting excellent versatility. For example, it can be used for inactive lithium titration reactions of lithium-ion batteries of various capacities, or for inactive sodium titration reactions of sodium-ion batteries of various capacities. In this case, the solid reactant is typically an electrode (one or more of lithium-ion battery electrodes and sodium-ion battery electrodes), containing inactive lithium or inactive sodium. The inactive lithium typically includes one or more of Li, LiH, Li₂CO₃, HOCH₂CH₂OCO₂Li (LiEMC), and Li₂C₂. The reaction solution can be one or more of ethanol, deuterated ethanol, heavy water, and sulfuric acid. The types of inactive sodium can be referenced to inactive lithium.
[0125] The following steps can be used as a reference for operating the reaction apparatus:
[0126] S1. Vacuum treatment is applied to the variable volume container;
[0127] S2. In a protective atmosphere, place the solid reactant inside the reactor's reaction chamber (on a solid reactant support or outside the reaction liquid buffer container); connect the vacuum-treated variable volume container to the reactor, and control the isolation of the variable volume container from the reactor's reaction chamber; and control the isolation of the reaction chamber from the outside environment.
[0128] S3. Control the variable volume container to connect with the reaction chamber and inject the reaction liquid into the reaction chamber;
[0129] S4. After the reaction solution is injected, control the variable volume container to isolate it from the reaction chamber;
[0130] S5. Invert the reactor to bring the reaction liquid into contact with the solid reactants, causing a reaction that produces gas.
[0131] S6. After the reaction is complete, extract the gas in the reaction chamber for testing.
[0132] All steps except step S2 can be performed in an atmospheric environment.
[0133] Before step S5, a step of injecting an internal standard gas into the reaction chamber may be included. The internal standard gas may be an inert gas, such as one or more of helium, neon, and argon.
[0134] By injecting an internal standard gas, the detection results can be made unaffected by the state of the detection system, thus improving the accuracy of the results. Taking the detection of metallic lithium with helium as the internal standard gas as an example, the following relationship will be satisfied during the detection of the gas after the reaction (e.g., gas chromatography detection):
[0135] 2Li + 2H + →2Li + +H2↑(1);
[0136] According to equation (1), the volume V of hydrogen gas produced in the reaction is... H2 for:
[0137] V H2 =(m Li / 2M Li )*22.4(2);
[0138] Where m Li M represents the mass of lithium metal. Li is the relative atomic mass of lithium metal.
[0139] Let a = 22.4 / 2M Li Then V H2 =a*m Li (3);
[0140] According to equation (3), to obtain the mass of metallic lithium, it is necessary to measure the volume V of the generated hydrogen gas. H2 .
[0141] Furthermore, after the reaction is complete, the gases in the reaction chamber satisfy the following relationship:
[0142] V H2 =C H2 V 总 C H2 =а(t)K H2 S H2 (4);
[0143] V He =C He V 总 C He =а(t)K He S He (5);
[0144] Among them, V H2 C is the volume of hydrogen gas produced in the reaction. H2K is the concentration of hydrogen in the mixed gas inside the reactor. H2 It is a constant related to hydrogen in the detection system (which can be obtained from a standard curve), S H2 It is the peak area of hydrogen;
[0145] V He C is the volume of helium gas injected. He It is the concentration of helium in the mixed gas inside the reactor, K. He It is a constant related to helium in the detection system (which can be obtained from a standard curve), S He It is the peak area of helium;
[0146] V 总 It is the total volume of the mixed gas inside the reaction chamber;
[0147] а(t) represents the state parameters of the gas detection system at different times.
[0148] According to equations (4) and (5), we can obtain:
[0149] V H2 / V He =K H2 / K He *(S H2 / S He (6);
[0150] Let d = K H2 / (K He a) Then, according to equations (3) and (6), we can obtain:
[0151] m Li =d*(S H2 / S He )*V He (7);
[0152] According to equation (7), when He gas is introduced as an internal standard gas, the titration test results will not be affected by the state parameter α(t) of the gas detection system. Even if the detection system has been used for a long time or has tested other samples, the accuracy of the test results will not be reduced.
[0153] [Detection System]
[0154] This application also provides a chemical detection system, including the above-described reaction apparatus.
[0155] The aforementioned reaction apparatus can be integrated into a chemical detection system for automatic or manual detection. For example, automatic sampling can be achieved by connecting an automatic sampling unit to the sampling port of the reaction apparatus. Simultaneously, the automatic sampling unit can be connected to an automatic sample delivery unit, which delivers the gas sample collected by the automatic sampling unit to the detection equipment (e.g., chromatograph, mass spectrometer) for analysis. Alternatively, the reaction apparatus can be connected to an automatic liquid injection device to automatically add reaction solution to the apparatus. Using this chemical detection system, the operational resistance during the detection process is low, and the detection results have high accuracy.
[0156] In some embodiments, the chemical detection system includes one or more of an inactive lithium detection system and an inactive sodium detection system.
[0157] This chemical detection system can be used to detect inactive lithium in lithium-ion batteries and / or inactive sodium in sodium-ion batteries. The lithium-ion or sodium-ion batteries can be small-capacity batteries (e.g., batteries with a capacity less than 1000mAh, such as 50mAh to 100mAh) or large-capacity batteries (e.g., batteries with a capacity greater than 1000mAh, such as 1000mAh to 6500mAh, or even larger). The chemical detection system in this application, including the aforementioned reaction apparatus, can detect batteries of various capacities and is expected to be widely used in practical battery testing.
[0158] The reaction apparatus of the present application embodiment will be described in more detail below with reference to the accompanying drawings.
[0159] Example 1
[0160] Please refer to Figure 1 This application provides a reaction apparatus for quantitative detection of inactive lithium in lithium-ion batteries, including a reactor 100, an air bag 200, and a sample rack 300.
[0161] (1) Reactor 100
[0162] The reactor 100 includes a cup body 101, a cover 102, and a liquid guide tube 103. The cup body 101 is provided with a reaction chamber. The cover 102 is detachably and sealingly fitted onto the cup body 101, and a sealing gasket is provided in the cover 102. The cover 102 has a liquid inlet, a vent, and a sampling port 104, all of which are connected to the reaction chamber.
[0163] The inlet is used to inject the reaction solution. A first two-way valve 105 is provided on the inlet to control the opening and closing of the inlet. A sealing cap 106 is provided on the first two-way valve 105, and a sealing gasket is provided in the sealing cap 106. An injection hole is also provided in the sealing cap 106.
[0164] The vent is used to connect to the air bag 200. A second two-way valve 107 is provided on the vent to control the opening and closing of the vent.
[0165] The sampling port 104 is used to take samples from inside the cup body 101. A sealing gasket is provided in the sampling port.
[0166] One end of the liquid guide tube 103 is set on the cover 102 and connected to the liquid inlet, and the whole is located inside the reaction chamber.
[0167] (2) Airbag 200
[0168] The gas bag 200 has a connection port with a rotary valve 201 for controlling the connection and isolation between the gas bag 200 and the outside world. The rotary valve 201 is connected to the second two-way valve 107 in the reactor 100 via a gas pipe 202. When the rotary valve 201 is closed, and / or the second two-way valve 107 is closed, the gas bag 200 is isolated from the reaction chamber; when both the rotary valve 201 and the second two-way valve 107 are open, the gas bag 200 is connected to the reaction chamber.
[0169] (3) Sample rack 300
[0170] Please refer to Figure 2 The sample holder 300 includes a frame 301 and a solid reactant support 302 disposed on the frame 301. The frame 301 is located at the bottom of the cup body 101. The solid reactant support 302 has a vertical through hole 303 (that is, in the height direction of the cup body 101). The liquid guide tube 103 in the reactor 100 passes through the through hole 303 on the solid reactant support 302 and extends to the bottom of the solid reactant support 302, with the bottom of the liquid guide tube 103 located between the solid reactant support 302 and the bottom of the reaction chamber.
[0171] The reaction apparatus of this embodiment is used for the quantitative detection of inactive lithium in lithium-ion batteries. Taking the detection of inactive lithium in the graphite electrode of a lithium-ion battery as an example, the detection process can be referred to the following steps:
[0172] Step 1: Extract and clean the graphite electrode.
[0173] In a glove box, the graphite electrode was removed from the disassembled battery and gently rinsed three times per minute in a small amount of dimethyl carbonate (DMC) to remove residual electrolyte and prevent residual ethylene carbonate from releasing CO2 during titration, which could affect the CO2 detection of the gas detection equipment. After rinsing, the graphite electrode was sealed and stored as a sample.
[0174] Step 2: Vacuum treatment of the air bag 200.
[0175] Rotate the rotary valve 201 of the gas bag 200 (not connected to the reactor 100) to the connected state, so that the internal atmosphere of the gas bag 200 can communicate with the external atmosphere. Then, use a vacuum pump to evacuate the inside of the gas bag 200 to a vacuum state, and rotate the rotary valve 201 to the closed state, so that the internal atmosphere of the gas bag 200 is kept under vacuum and isolated from the external atmosphere.
[0176] Step 3: Sample assembly before testing.
[0177] First, open the cover 102 outside the glove box to expose the reaction chamber to the atmosphere; then, transfer the vacuum gas bag 200 and the open reactor 100 into the glove box through the transition chamber. Afterwards, the sample stored in the glove box ( Figure 1 The sample 400 is removed from the sealed bag and placed onto the solid reactant support 302 of the sample holder 300. Then, confirm that both the first two-way valve 105 and the second two-way valve 107 are closed. Align the liquid guide tube 103 vertically with the through-hole 303 of the solid reactant support 302 and pass it through the through-hole 303. Then, tighten the cover 102 to ensure a seal. Finally, after confirming that the sealing cover 106 is tightened and sealed, and connecting the vacuum bag 200 to the second two-way valve 107 via the air tube 202, the assembled reaction apparatus can be removed from the glove box.
[0178] Step 4: Injection of the quantitative titration solution.
[0179] First, change the states of the rotary valve 201 of the gas bag 200, as well as the first two-way valve 105 and the second two-way valve 107, so that all of them are in the connected state. Then, use the injector 500 to draw a fixed amount of titration solution, and inject the fixed amount of titration solution stored in the injector 500 through the injection hole of the sealing cap 106. The titration solution will be injected into the lower layer of the solid reactant support 302 through the through hole 303 on the guide tube 103 connected to the first two-way valve 105. After the titration solution is injected, change the states of the first two-way valve 105 and the second two-way valve 107 so that both are in the closed state. Remove the injector 500 to complete the injection of the titration solution. Additionally, the air bag 200 connected to the second two-way valve 107 can also be removed when the second two-way valve 107 is in the closed state.
[0180] Note: The horizontal height of the through hole 303 of the solid reactant support 302 is designed based on the horizontal height of the titration solution after injection at the maximum injection volume. The horizontal height of the through hole 303 of the solid reactant support 302 is higher than the horizontal height of the titration solution after injection at the maximum injection volume.
[0181] Step 5: Quantitative injection of internal standard helium.
[0182] First, change the state of the first two-way valve 105 to the open state. Then, use the gas-tight sampling needle 600 to extract a fixed amount of high-purity helium (concentration ≥99.999%) from the helium cylinder / bag. Next, inject the fixed amount of helium stored in the gas-tight sampling needle 600 into the cup body 101 through the injection hole of the sealing cap 106. After the helium injection is complete, change the state of the first two-way valve 105 to the closed state, and remove the gas-tight sampling needle 600. This completes the injection of the internal standard helium.
[0183] Step Six: Begin the titration experiment.
[0184] The reactor 100 is inverted so that the titration solution in the lower layer of the solid reactant support 302 enters the upper layer of the solid reactant support 302 through the through hole 303 and comes into contact with the sample 400 to react and produce gas.
[0185] Note: When the titration solution reacts with the sample, the reaction rate can be increased by ultrasound to make the reaction more complete.
[0186] Step 7: Measure the amount of each gas produced in the experiment.
[0187] After the reaction is complete, the reactor 100 is placed upright, and the gas is mixed evenly by shaking. After the gas is mixed evenly, a quantitative amount of reaction gas is extracted from the sampling port 104 using an airtight gas sampling needle 600 and injected into a gas detection device (such as a gas chromatograph) for detection.
[0188] Step 8: Complete the test.
[0189] When the signal intensity of each gas detected by the gas detection device completely decays and returns to the baseline, it means that the quantitative amount of gas injected through the gas-tight sampling needle 600 has been completely detected. At this point, the gas detection device can be stopped, and the titration test of the non-active lithium content of the sample can be completed.
[0190] Furthermore, the data obtained through the above titration test needs to be used to quantitatively detect the inactive lithium content in the sample based on the following two points, thus completing the construction of the titration quantitative detection capability. Taking the detection of lithium metal in the sample as an example:
[0191] 1) Before sample testing, the entire testing system needs to be calibrated to establish a standard curve to obtain the direct relationship between the integrated area of the H2 gas gas chromatographic signal and the amount of lithium metal in the sample. The standard curve is established using the internal standard method. Specifically, a series of known weights of lithium metal are placed in the reaction apparatus and titrated with ethanol according to the experimental steps described above. The generated gases are then subjected to gas chromatography testing. The integrated signal areas of hydrogen and helium are obtained after the tests. The hydrogen integrated area of each lithium metal is divided by the helium integrated area to obtain the hydrogen integrated area relative to helium for each lithium metal, i.e., S. H2 / S He By mapping these calculated relative integral areas to the lithium metal mass, a series of data points can be obtained. By fitting these data points, a standard curve can be obtained.
[0192] 2) After the standard curve of the gas is established, the electrode sample is tested according to the above experimental steps based on the established standard curve. The relative integral area of hydrogen gas relative to helium gas obtained after the electrode sample test is substituted into the standard curve to obtain the content of metallic lithium in the electrode sample.
[0193] Example 2
[0194] The difference between this embodiment and Embodiment 1 is that the sample holder 300 is replaced with a buffer bottle 300a, which is placed inside the cup body 101. Figure 3 As shown.
[0195] The method for quantitative detection of inactive lithium in lithium-ion batteries using the reaction apparatus of this embodiment is the same as in Embodiment 1, except that:
[0196] In step three, after transferring the vacuum bag 200 and the open reactor 100 into the glove box, first remove the buffer bottle 300a from the container 101. Then, remove the sample 400 stored in the glove box from the sealed bag and place it into the container 101. After all the sample 400 is placed into the container 101, the buffer bottle 300a must be placed back into the container 101. The lower end of the liquid delivery tube 103 is inserted into the buffer bottle 300a, with the sample 400 outside the buffer bottle 300a. Afterward, confirm the airtightness of the relevant structures and remove the reaction apparatus from the glove box.
[0197] Accordingly, in step six, the reactor 100 is inverted, and the titration solution in the buffer bottle 300a is poured out into the cup 101; then the reactor 100 is turned upright, so that the titration solution and the sample 400 come into contact and react to produce gas.
[0198] It should be noted that this application is not limited to the above-described embodiments. The above embodiments are merely examples, and any embodiments with the same structure and effect as the technical concept within the scope of this application are included in the technical scope of this application. Furthermore, various modifications that can be conceived by those skilled in the art to the embodiments, and other ways of constructing by combining some of the constituent elements of the embodiments, without departing from the spirit of this application, are also included in the scope of this application.
Claims
1. A reaction apparatus characterized by comprising: Includes reactors, variable volume containers, and solid-liquid separation components; The reactor is provided with a liquid inlet and a reaction chamber communicating with the liquid inlet; the liquid inlet is used to inject reaction liquid into the reaction chamber; the reaction chamber is used to contain the reaction liquid and solid reactants; The variable volume container is selectively connected to or isolated from the reaction chamber; The solid-liquid isolation component is disposed inside the reaction chamber to isolate the reaction liquid from the solid reactants.
2. The reaction apparatus according to claim 1, wherein The variable volume container is equipped with a variable volume container switching valve; the variable volume container switching valve is used to control the connection or isolation of the variable volume container from the outside world.
3. The reaction apparatus according to claim 1 or 2, wherein The variable volume container includes one or more of the following: air bag, balloon, and syringe.
4. The reaction apparatus of claim 3, wherein The total volume of the variable-volume container is greater than or equal to the total volume of the reaction liquid.
5. The reaction apparatus of claim 4, wherein The solid-liquid isolation component includes a solid reactant support, and a gap is provided between the solid reactant support and the bottom of the reaction chamber; The solid reactant support has a through hole, and / or a gap is provided between the solid reactant support and the side wall of the reaction chamber.
6. The reaction apparatus of claim 5, wherein The distance between the solid reactant support and the bottom of the reaction chamber is greater than the height of the reaction liquid within the reaction chamber.
7. The reaction apparatus according to claim 5 or 6, wherein The solid-liquid isolation component also includes a support body, which is disposed within the reaction chamber, and the solid reactant support is disposed on the support body.
8. The reaction apparatus according to claim 5 or 6, wherein The solid reactant support is fixedly mounted on the side wall of the reaction chamber.
9. The reaction apparatus of claim 4, wherein The solid-liquid isolation component includes a reaction liquid buffer container.
10. The reaction apparatus of claim 9, wherein The total volume of the reaction solution buffer container is greater than or equal to the total volume of the reaction solution.
11. The reaction apparatus according to claim 5 or 6, wherein The reactor also includes a liquid guide pipe, one end of which is connected to the liquid inlet, and the other end is located inside the reaction chamber; Simultaneously, the liquid guide tube passes through the through hole on the solid reactant support, or the liquid guide tube passes through the gap between the solid reactant support and the side wall of the reaction chamber.
12. The reaction apparatus according to claim 9 or 10, wherein The reactor also includes a liquid guide pipe, one end of which is connected to the liquid inlet, and the other end is located inside the reaction chamber; Meanwhile, the liquid guide tube is positioned above the reaction solution buffer container, or the liquid guide tube extends into the reaction solution buffer container.
13. The reaction apparatus according to claim 1 or 2, wherein The solid reactants include electrodes.
14. A chemical detection system characterized by, Includes the reaction apparatus described in any one of claims 1 to 13.
15. The chemical detection system of claim 14, wherein, The chemical detection system includes one or more of the following: an inactive lithium detection system and an inactive sodium detection system.