Cell gas production rate measuring device

Abstract

The utility model discloses a device for measuring the gas production rate of a battery cell, which comprises the components of a base of which the middle part of the upper end is used for placing the battery cell; the gas measuring pipe is horizontally arranged, sleeves the battery cell and can move up and down along the base, scales are arranged on the outer surface of the gas measuring pipe, the gas measuring pipe is filled with a liquid column, and a gas inlet of the gas measuring pipe is communicated with the interior of the battery cell through a connecting pipe and a liquid injection port of the battery cell. Thus, gas generated in pre-lithium battery cell infiltration enters the connecting pipe communicated with the liquid injection port through the liquid injection port and enters the gas measuring pipe through the connecting pipe, and a liquid column injected into the gas measuring pipe in advance moves in the gas measuring pipe when subjected to gas pressure in the battery cell; the gas production rate of the battery cell in the infiltration period can be measured according to the volume scales on the gas measuring pipe through which the liquid column passes, so that the gas data collection efficiency in the research and development of the pre-lithium battery cell is greatly improved, and accurate data analysis can be provided in the research and development process of the pre-lithium battery cell.

Description

Technical Field

[0001] The utility model relates to the technical field of gas production measurement of pre-lithium battery cells, in particular to a device for measuring gas production of battery cells. Background Art

[0002] In recent years, the development of lithium-ion batteries has been very rapid. With the development of electronic products, new energy vehicles and energy storage industries, human beings have higher and higher requirements for the energy density of lithium batteries. In recent years, people have become more and more urgent to develop high-energy-density batteries, so lithium-ion battery lithium replenishment technology has received more and more attention from scientific research institutions and enterprises. When a lithium-ion battery is charged for the first time, lithium ions are released from the positive electrode through the electrolyte and the diaphragm to the surface of the negative electrode, and a layer of solid electrolyte interface film, which is the SEI film we are familiar with, will be generated on the surface of the negative electrode. The generation of such an interface film will consume a large amount of lithium ions, and because the SEI film is not densely grown and the positive and negative electrode materials have large volume expansion and contraction during the cycle, some components of the SEI film can be dissolved in the electrolyte, resulting in the continuous growth of the SEI film on the surface of the positive and negative electrodes, which continuously consumes lithium ions in the battery. Therefore, if lithium ions can be continuously provided to the battery during the first charge and discharge of the battery and the subsequent charge and discharge cycles to reduce the loss of active lithium in the lithium battery, scientific research institutions and enterprises have begun to develop various pre-lithium technologies to replenish lithium batteries.

[0003] At present, the pre-lithiation technologies include: in-situ doping pre-lithiation, contact pre-lithiation, electrochemical pre-lithiation and chemical pre-lithiation. Among them, the use of lithium metal to electrochemically pre-lithiate the negative electrode is a pre-lithiation strategy that is currently widely studied and adopted, including direct contact pre-lithiation, external short-circuit pre-lithiation, external power supply pre-lithiation and other methods. The electrochemical pre-lithiation of lithium metal composited on the negative electrode of the outermost battery cell will form a half-battery during the infiltration process of a high-temperature oven after the electrolyte is injected. Due to the short circuit between lithium and the negative electrode, it will discharge at a low voltage during the infiltration process, which is equivalent to premature formation. During this process, the pre-lithiation battery cell will produce gas, and it is difficult to measure and count the gas production, resulting in the inability to provide accurate data analysis for the development of pre-lithiation batteries. Utility Model Content

[0004] In order to solve the technical problems existing in the background technology, the utility model proposes a battery cell gas production measurement device.

[0005] The utility model provides a battery cell gas production measurement device, comprising:

[0006] A base, the middle part of the upper end of which is used to place the battery cell;

[0007] The gas measuring tube is placed horizontally, sleeved outside the battery core, and can move up and down along the base. The outer surface of the gas measuring tube is provided with a scale and the interior is filled with a liquid column. The air inlet of the gas measuring tube is connected with the interior of the battery core through a connecting tube and the liquid injection port of the battery core.

[0008] Preferably, it also includes a supporting plate for supporting the gas measuring tube, columns are provided at the four corners of the upper end of the base, a slide rail is provided on the inner side of each column, and a self-locking slider is provided on the supporting plate, and the self-locking slider can extend into the slide rail and move.

[0009] Preferably, the gas measuring tube is identical at both ends and open at both ends, one end opening is set as the air inlet, and the other end opening is set as the air outlet.

[0010] Preferably, the connecting tube is a rubber tube, one end of which is connected to the air inlet and sealed, and the other end of which is connected to the interior of the battery cell in the liquid injection port.

[0011] Preferably, a dripping port is further provided on the gas measuring tube near the air inlet, and the liquid column is injected into the zero scale of the gas measuring tube through the dripping port.

[0012] Preferably, the gas measuring tube is made of a transparent material.

[0013] In summary, the utility model has the following beneficial effects: first, the gas measuring tube is moved up and down to a position flush with the liquid injection port of the battery cell, and then the gas inlet of the gas measuring tube at one end of the connecting tube is connected and sealed, and the other end is connected to the inside of the battery cell in the liquid injection port. When the battery cell generates gas during high-temperature immersion, the gas will enter the gas measuring tube to push the liquid column to move in the gas measuring tube. The scale of the liquid column movement can be recorded within a certain period of time to calculate the gas production volume of the battery cell in a certain period of time. The gas production of the battery cell during the immersion period can be measured according to the volume scale of the liquid column passing through the gas measuring tube, which greatly improves the efficiency of gas data collection in the research and development of pre-lithium batteries and can provide accurate data analysis for the research and development of pre-lithium batteries.

[0014] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The figure is a schematic structural diagram of a device for measuring gas production of a battery cell according to an embodiment of the utility model.

[0016] In the figure:

[0017] 1. Base; 2. Air measuring tube; 3. Support plate; 4. Air outlet; 5. Drip port; 6. Air inlet; 7. Rubber tube; 8. Battery cell; 9. Column. DETAILED DESCRIPTION

[0018] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar symbols throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0019] like Figure 1 As shown, a battery cell gas production measurement device proposed in this embodiment includes:

[0020] The base 1 has a middle portion at the upper end thereof for placing the battery cell 8;

[0021] The gas measuring tube 2 is placed horizontally, sleeved outside the battery cell 8, and can move up and down along the base 1. The outer surface of the gas measuring tube 2 is provided with a scale and the inside is filled with a liquid column. The air inlet of the gas measuring tube 2 is connected to the inside of the battery cell 8 through the connecting tube and the liquid injection port of the battery cell 8.

[0022] Specifically, the connecting tube is set as a rubber tube 7, one end of which is connected to the air inlet 6 and sealed, and the other end is connected to the inside of the battery cell 8 in the liquid injection port. The gas generated during the infiltration of the pre-lithium battery cell enters the rubber tube 7 connected to it from the liquid injection port, and enters the gas measuring tube 2 from the rubber tube 7. The liquid column previously injected into the gas measuring tube 2 will move in the gas measuring tube 2 when it is subjected to the gas pressure in the battery cell 8. The gas production of the battery cell during the infiltration period can be measured according to the volume scale on the gas measuring tube 2 where the liquid column passes.

[0023] In this way, first move the gas measuring tube up and down to the same level as the liquid injection port of the battery cell, then connect and seal the gas inlet of the gas measuring tube at one end of the connecting tube, and connect the other end to the inside of the battery cell in the liquid injection port. When the battery cell generates gas during high-temperature immersion, the gas will enter the gas measuring tube to push the liquid column to move in the gas measuring tube. By recording the scale of the liquid column movement within a certain period of time, the gas production volume of the battery cell in a certain period of time can be calculated. The gas production of the battery cell during the immersion period can be measured based on the volume scale of the liquid column passing through the gas measuring tube, which greatly improves the efficiency of gas data collection in the development of pre-lithium batteries and can provide accurate data analysis for the development of pre-lithium batteries.

[0024] Furthermore, it also includes a support plate 3 for supporting the gas measuring tube 2. The gas measuring tube 2 is placed horizontally on the support plate 3. Columns 9 are provided at the four corners of the upper end of the base 1. The inner side of each column 9 is provided with a slide rail. The support plate 3 is provided with a self-locking slider, which can be extended into the slide rail and move. The support plate 3 can move up and down on the four columns 9 of the base 1, carrying the gas measuring tube 2 to move up and down until it is on the same horizontal line as the liquid injection port of the battery cell 8, eliminating the pressure difference caused by the height difference that affects the accuracy of the gas production measurement, and can adapt to different sizes of pre-lithium batteries for gas production measurement.

[0025] Among them, the specific structure of the self-locking slider can refer to the existing structure, and will not be repeated in this article.

[0026] In this embodiment, the gas measuring tube 2 is identical at both ends and open at both ends, one end opening is set as the air inlet 6, and the other end opening is set as the air outlet 4. Specifically, in order to facilitate observation and recording of scale values, the gas measuring tube 2 is set as a transparent material, specifically transparent PVC (Polyvinyl chloride), glass, etc., to ensure that the moving position of the liquid column in the gas measuring tube 2 can be observed.

[0027] Among them, a dripping port 5 is also provided on the gas measuring tube 2 near the air inlet 6, and the liquid column is injected into the zero scale of the gas measuring tube 2 through the dripping port 5. Before work, the liquid column is injected into the gas measuring tube 2 through the dripping port 5, and the dripping port 5 is sealed to ensure that the front and back of the gas measuring tube 2 are separated by the liquid column, and the gas pressure can push the liquid column to move in the gas measuring tube 2. It should be noted that the liquid column moving in the gas measuring tube 2 cannot be a solution that can react with the gas produced by the battery cell, and it is also a non-volatile solution.

[0028] In summary, after the battery cell is filled with liquid, the battery cell 8 is placed in the middle empty space of the base 1 when it is placed in the oven. First, move the support plate 3 to drive the measuring air tube 2 to move up and down to the same level as the battery cell filling port. Then, one end of the rubber tube 7 is connected and sealed to the air inlet 6 of the measuring air tube 2, and the other end is connected to the inside of the battery cell 8 in the filling port. Before the start of the infiltration, open the drip port 5, inject the liquid column into the measuring air tube 2 to keep the liquid column at the zero scale of the measuring air tube 2, and seal the drip port 5 again. During the entire infiltration process, keep the gas outlet 4 of the measuring air tube 2 unsealed. When the battery cell 8 generates gas during the high-temperature infiltration, the gas will enter the measuring air tube 2 to push the liquid column to move in the measuring air tube 2. By recording the scale of the liquid column movement within a certain period of time, the gas production volume of the battery cell in a certain period of time can be calculated.

[0029] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0030] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection, an electrical connection, or communication with each other; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0032] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0033] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A device for measuring gas production of a battery cell, characterized in that: include: A base, the middle part of the upper end of which is used to place the battery cell; The gas measuring tube is placed horizontally, sleeved outside the battery core, and can move up and down along the base. The outer surface of the gas measuring tube is provided with a scale and the interior is filled with a liquid column. The air inlet of the gas measuring tube is connected with the interior of the battery core through a connecting tube and the liquid injection port of the battery core.

2. The battery cell gas production measurement device according to claim 1, characterized in that: It also includes a support plate for supporting the gas measuring tube, columns are provided at the four corners of the upper end of the base, a slide rail is provided on the inner side of each column, and a self-locking slider is provided on the support plate, and the self-locking slider can extend into the slide rail and move.

3. The battery cell gas production measurement device according to claim 1, characterized in that: The gas measuring pipe is identical at both ends and open at both ends, one end opening is set as the gas inlet, and the other end opening is set as the gas outlet.

4. The battery cell gas production measurement device according to claim 2, characterized in that: The connecting tube is configured as a rubber tube, one end of which is connected to the air inlet and sealed, and the other end of which is connected to the inside of the battery cell in the liquid injection port.

5. The battery cell gas production measurement device according to claim 1, characterized in that: The gas measuring tube is also provided with a dripping port near the air inlet, through which the liquid column is injected into the zero scale of the gas measuring tube.

6. The battery cell gas production measurement device according to claim 1, characterized in that: The gas measuring tube is made of transparent material.

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