Automatic sampling and sampling instrument and method for battery bulge gas

Abstract

The invention discloses an automatic sampling and sampling instrument and method for battery swelling gas, and relates to the technical field of battery swelling gas detection.The instrument comprises a sampling needle, a sample tube, a sample injector and a vacuum pump which are sequentially connected, a valve A is arranged between the sampling needle and the sample tube, and a valve B is arranged between the sample tube and the sample injector; a valve C is arranged between the sample injector and the vacuum pump; one end of the valve D is communicated with the sample tube, the other end of the valve D is communicated with the standard gas cylinder, and the adjusting mechanism and the pressure gauge are both arranged on a pipeline between the valve B and the valve C. The whole process of sampling and sample introduction of sample gas can be realized, and sampling and sample introduction of battery bulge gas can be completed by one machine; the method comprises a sampling and sampling method of battery bulge gas and standard gas, automatic sampling and repeated sampling can be realized when the battery bulge gas is sampled, the accuracy of a detection result is ensured, and pressure control can be realized when the standard gas is sampled.

Description

Technical Field

[0001] The present invention relates to the technical field of battery bulge gas detection, and specifically to an automatic sampling and injection instrument and method for battery bulge gas. Background Art

[0002] Battery bulging gas detection is an important part of battery safety testing. Its main purpose is to promptly detect and deal with battery bulging problems to prevent serious consequences such as battery explosion or fire. The gases in battery bulging gas are generally hydrogen, oxygen, nitrogen, carbon monoxide, carbon dioxide, methane, and hydrocarbon gas components above carbon 2 (C2, such as ethane, ethylene, propane, etc.). Due to the small size of the battery, the amount of gas sample generated by bulging is also very small. During the detection, there have always been problems such as sampling difficulties and inaccurate detection due to air mixing into the sample gas.

[0003] Specifically, the existing sampling and injection method is to use a gas-tight needle for sampling and injection, which first pierces the outer packaging of the battery with a gas-tight needle, then extracts the gas in the battery, and then adjusts the scale value of the gas-tight needle to insert the gas-tight needle into the injection port of the gas chromatograph, and then manually injects the sample gas in the gas-tight needle into the injection port of the gas chromatograph, and the gas chromatograph analyzes the gas composition. In practice, this sampling and injection method has the following main defects: First, due to the presence of a large amount of oxygen and nitrogen in the air, the amount of gas in the battery bulge is relatively small (generally a few milliliters to tens of milliliters). At the same time, most batteries are packaged in aluminum foil composite bags. Since the aluminum foil composite bags are not elastic, when the airtight needle pierces the aluminum foil composite bag, it cannot be well sealed. When the airtight needle is used to extract the gas in the battery sample, the battery is exposed to the air. The oxygen and nitrogen components in the air will inevitably mix into the battery and be extracted into the syringe by the sampling needle, causing the sample to be disturbed and contaminated by the air, resulting in inaccurate detection.

[0004] Secondly, the current method of sampling with a gas-tight needle is used, and the gas chromatographs are all configured to sample from an injection port. It is necessary to manually transfer the standard gas to a gas sampling bag, then pierce the bag with a gas-tight needle, collect the standard gas in the bag, and then insert the gas-tight needle into the injection port for sampling and analysis. However, during the sampling and transfer process, air components may contaminate the standard gas, resulting in inaccurate detection.

[0005] Third, due to the small amount of battery gas samples, the airtight needle cannot be resealed after sampling. The pinholes in the aluminum foil composite bag are exposed to the air, and air components may enter the aluminum foil composite bag, making repeated sampling impossible.

[0006] Fourthly, the gas-tight needle sampling is performed manually, which may easily introduce artificial errors into the analysis results, resulting in inaccurate test results. Summary of the invention

[0007] The purpose of the present invention is to overcome the shortcomings of the prior art and to provide an automatic sampling and injection instrument and method for battery bulging gas, which can complete the sampling and injection of battery bulging gas and standard gas in one machine. When sampling battery bulging gas, automatic sampling and repeated injection can be achieved to ensure accurate detection results. When sampling standard gas, pressure control can be achieved and standard curves can be quickly and automatically prepared.

[0008] The objective of the present invention is achieved through the following technical solutions: A battery bulging gas automatic sampling and injection instrument, comprising a sampling needle, a sample tube, an injector, and a vacuum pump, wherein the sampling needle, the sample tube, the injector, and the vacuum pump are connected in sequence, a valve A is provided between the sampling needle and the sample tube, a valve B is provided between the sample tube and the injector, and a valve C is provided between the injector and the vacuum pump; It also includes a standard gas cylinder, a valve D, an adjusting mechanism and a pressure gauge, one end of the valve D is connected to the sample tube, and the other end of the valve D is connected to the standard gas cylinder. The adjusting mechanism and the pressure gauge are both arranged on the pipeline between the valve B and the valve C. The pressure gauge is used to detect the air pressure in the pipeline, and the adjusting mechanism is used to adjust the air flow rate or flow rate in the pipeline.

[0009] Furthermore, it also includes a gas chromatograph, which is connected to the injector, and the injector is used to quantitatively transfer the gas flowing through to the gas chromatograph.

[0010] Furthermore, it also includes an airbag, an airbag valve and a driving mechanism, the airbag is used to cover the battery to be tested, one end of the airbag valve is connected to the airbag, the end of the sampling needle away from valve A is the front end, and the front end of the sampling needle is arranged opposite to the end of the airbag valve away from the airbag, and the driving mechanism is used to drive the sampling needle and the airbag valve to approach each other or move away from each other. When the sampling needle and the airbag valve are close to each other, the front end of the sampling needle can pierce the airbag valve and extend into the airbag. The sampling needle can also pierce the bulge of the battery to be tested in the airbag. When the sampling needle and the airbag valve are separated from each other, the airbag valve can achieve self-sealing.

[0011] Specifically, a spacer made of soft and elastic material is arranged in the air bag valve.

[0012] Specifically, the sampling needle adopts a side opening design.

[0013] Specifically, it also includes an air bag clamp, which includes an upper clamp, a lower clamp and a lock. The upper clamp is rotatably connected to the lower clamp. When the upper clamp and the lower clamp are closed, a clamping hole is formed. The air bag valve is inserted into the clamping hole. The lock is used to fix the upper clamp and the lower clamp when they are closed.

[0014] Specifically, a positioning groove is processed on the circumference of the clamping hole, and a positioning platform is arranged on the circumference of the air bag valve, and the positioning platform is adapted to be arranged in the positioning groove.

[0015] Specifically, it also includes a body, the driving mechanism includes a first telescopic device and a second telescopic device, the sampling needle and the first telescopic device are both fixedly mounted on the body, the extending end of the first telescopic device is fixedly connected to the second telescopic device, and the extending end of the second telescopic device is fixedly connected to the lower clamp.

[0016] A battery bulge gas automatic sampling and injection method, which relates to the aforementioned battery bulge gas automatic sampling and injection instrument, includes a battery bulge gas sampling and injection method, and the battery bulge gas sampling and injection method includes the following steps: S1. Place the battery sample into the air bag and seal the air bag, keep the valve D closed and open the valves A, B and C; S2, driving the sampling needle and the air bag valve to approach each other through the driving mechanism, so that the front end of the sampling needle pierces the air bag valve and extends into the air bag; S3, start the vacuum pump to suck, and close valve B and valve C when the vacuum degree meets the requirements; S4, driving the sampling needle and the air bag valve to approach each other through the driving mechanism, so that the front end of the sampling needle continues to penetrate forward to the bulge position of the battery sample; S5, closing the valve A after delay control, and then opening the valve B; S6. Quantitatively transfer the gas passing through the sample injector to the gas chromatograph.

[0017] Furthermore, a battery bulging gas automatic sampling and injection method also includes a standard gas sampling and injection method, and the standard gas sampling and injection method includes the following steps: S1, setting the injection pressure and adjusting the injection flow rate through the regulating mechanism, keeping the valve A and valve D both in a closed state, and opening the valve B and valve C; S2, start the vacuum pump to perform suction, and close the valve C when the vacuum degree meets the requirement; S3, opening the valve D, and then closing the valve D after delay control; S4, open the valve C, and when the pressure value detected by the pressure gauge reaches the set injection pressure value, turn off the vacuum pump or close the valves B and C at the same time; S5, quantitatively transferring the gas that meets the set pressure value flowing through the gas chromatograph through the injector.

[0018] The beneficial effects of the present invention are: The automatic sampling and injection instrument for battery bulging gas includes a sampling needle, a sample tube, an injector, and a vacuum pump connected in sequence, a valve A is provided between the sampling needle and the sample tube, a valve B is provided between the sample tube and the injector, and a valve C is provided between the injector and the vacuum pump; it also includes a standard gas cylinder, a valve D, an adjustment mechanism, and a pressure gauge, one end of the valve D is connected to the sample tube, and the other end of the valve D is connected to the standard gas cylinder, and the adjustment mechanism and the pressure gauge are both provided on the pipeline between valve B and valve C. The automatic sampling and injection instrument for battery bulging gas can complete the whole process of sampling and injection of sample gas in sequence, and can realize the sampling and injection of battery bulging gas samples and standard gas samples in one machine. Specifically, its application includes a battery bulging gas sampling and injection method and a standard gas sampling and injection method, wherein: The battery bulge gas sampling and injection method needs to be used in conjunction with an air bag and an air bag valve. One end of the air bag valve is connected to the air bag, and the other end of the air bag valve is facing the front end of the sampling needle. The air bag valve has a self-sealing property. During sampling, the battery sample is loaded in the air bag. First, the sampling needle is inserted into the air bag to evacuate the air, and then the sampling needle is inserted into the battery bulge. Under the action of the pressure difference, the battery bulge gas is introduced into the sample tube to complete the sampling. Subsequently, under the same pressure difference, the gas sample in the sample tube is introduced to the injector and quantitatively injected into the gas chromatograph for analysis. During this process, the pressure gauge can detect and obtain the injection pressure parameters. According to the above working process, the automatic sampling and injection instrument for battery bulging gas can complete the whole process of sampling and injection of sample gas in sequence. Before sampling the battery bulging gas, all the air in the air bag and the system pipeline is first exhausted. The air bag plays the role of isolating the air for the battery sample, which can effectively avoid the influence of air mixing on the sampling accuracy. The whole sampling and transfer process is completed through pressure difference and valve control, avoiding the contamination of sample gas in the process of manual extraction and transfer, which is conducive to ensuring the accuracy of the test results. Because the air bag is set to vacuum and isolate the system, and the whole system sampling and injection process is controlled by valves, the collected samples are stored in a closed sample tube, and multiple injections can be achieved for the same battery. There is no possibility of sample contamination, and there is no need to worry about the accuracy of multiple parallel injections.

[0019] The standard gas sampling and injection method is to first set the injection pressure, keep valve A and valve D in the closed state, open valve B and valve C; then start the vacuum pump to suck, and close valve C until the vacuum requirement is met; then open valve D to allow the standard gas in the standard gas cylinder to flow to the sample tube to complete the sampling, and then close valve D after delay control; then open valve C, and the vacuum pump will extract the standard gas sample in the sample tube. When the pressure value detected by the pressure gauge reaches the set injection pressure value, turn off the vacuum pump or close the valve B and valve C at the same time; then transfer the flowing standard gas to the gas chromatograph for analysis through the injector. According to the above working process, the battery bulge gas automatic sampling and injection instrument can also complete the whole process of sampling and injection of standard gas in sequence, and can realize pressure control when completing the standard gas injection. In practical applications, only one bottle of high-concentration standard gas is needed. By injecting at different pressure setting values, a standard curve can be quickly and automatically prepared. There is no need for a dynamic diluter or multiple bottles of standard gas with different concentrations, saving money.

[0020] In addition, since the injection pressure can be controlled, if the concentration of a certain component in the sample gas is found to be too high during the analysis process after injection, the injection amount needs to be adjusted. For high concentrations, the injection pressure can be reduced, which is equivalent to sample dilution and can effectively prevent measurement errors caused by sample overload. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structural principle of an automatic sampling and injection instrument for battery bulging gas according to the present invention; Figure 2 This is a schematic structural diagram of a product embodiment of a battery bulging gas automatic sampling and injection instrument of the present invention; Figure 3 for Figure 2 A schematic diagram of the internal structure of the illustrated embodiment; Figure 4 for Figure 2 A schematic diagram of the structure of the driving mechanism in the illustrated embodiment; Figure 5 for Figure 2 A schematic diagram of the structure of the air bag clamp in the illustrated embodiment; Figure 6 for Figure 2 A schematic diagram of the structure of the air bag valve in the illustrated embodiment; In the figure, 1-sampling needle, 2-sample tube, 3-injector, 4-vacuum pump, 5-valve A, 6-valve B, 7-valve C, 8-valve D, 9-standard gas cylinder, 10-adjusting mechanism, 11-pressure gauge, 12-gas chromatograph, 13-air bag valve, 14-lock, 15-upper splint, 16-lower splint, 17-positioning groove, 18-positioning platform, 19-first telescopic device, 20-second telescopic device. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings, but the protection scope of the present invention is not limited to the following.

[0023] like Figures 1 to 6 As shown, an automatic sampling and injection instrument for battery bulging gas includes a sampling needle 1, a sample tube 2, an injector 3, and a vacuum pump 4, wherein the sampling needle 1 is a hollow needle tube structure with a pointed front end, and the injector 3 uses a multi-way valve (usually a six-way valve) and an injector with a quantitative ring, which can achieve accurate quantitative injection. The rear end of the sampling needle 1, the sample tube 2, the injector 3 and the vacuum pump 4 are connected in sequence, and a valve A5 is provided between the sampling needle 1 and the sample tube 2, a valve B6 is provided between the sample tube 2 and the injector 3, and a valve C7 is provided between the injector 3 and the vacuum pump 4. It also includes a standard gas cylinder 9, a valve D8, an adjusting mechanism 10 and a pressure gauge 11. One end of the valve D8 is connected to the sample tube 2, and the other end of the valve D8 is connected to the standard gas cylinder 9. The adjusting mechanism 10 and the pressure gauge 11 are both arranged on the pipeline between the valve B6 and the valve C7. The pressure gauge 11 is used to detect the air pressure in this section of the pipeline. The adjusting mechanism 10 can select a regulating valve or a self-made structure that can change the pipeline diameter, which is used to adjust the air flow rate or flow rate in this section of the pipeline.

[0024] The automatic sampling and injection instrument for battery bulging gas is also equipped with a gas chromatograph 12 and an air bag when in use. The gas chromatograph 12 is connected to the injector 3, and the injector 3 can quantitatively transfer the gas flowing through it to the gas chromatograph 12 for analysis. The air bag (not shown) is a flexible soft bag used to cover and load the battery to be tested; an air bag valve 13 is also provided on the air bag. During implementation, the air bag valve 13 uses a hollow pipe fitting, and a septum made of the above-mentioned soft elastic material such as silicone, polytetrafluoroethylene, Teflon, Tedlar is provided therein so that the air bag valve 13 has a self-sealing function. The air bag and the air bag valve 13 are matching consumables, and one end of the air bag valve 13 is connected to the air bag as a whole. When loaded on the automatic sampling and injection instrument for battery bulging gas, the front end of the sampling needle 1 is arranged opposite to the end of the air bag valve 13 away from the air bag. The battery bulge gas automatic sampling and injection instrument is also provided with a driving mechanism, which is used to drive the sampling needle 1 and the air bag valve 13 to approach or move away from each other: when the sampling needle 1 and the air bag valve 13 approach each other, the front end of the sampling needle 1 can pierce the air bag valve 13 and extend into the air bag; when the sampling needle 1 continues to move toward the air bag valve 13, the front end of the sampling needle 1 can further pierce the bulge of the battery to be tested in the air bag; when the sampling needle 1 and the air bag valve 13 move away from each other and separate, the air bag valve 13 can achieve self-sealing.

[0025] In the battery bulge gas detection, the battery bulge gas needs to be extracted to the gas chromatograph for analysis. During the analysis, the content of the sample gas components needs to be calculated through the injection gas pressure, gas equation and standard gas content. When the battery bulge gas automatic sampling and injection instrument is used, it can complete two modes: battery bulge gas sampling and injection and standard gas sampling and injection.

[0026] The battery bulge gas sampling method includes the following steps: S1. Place the battery sample into an air bag and seal the air bag, keep valve D8 closed and open valves A5, B6 and C7.

[0027] S2. Drive the sampling needle 1 and the air bag valve 13 toward each other through the driving mechanism, so that the front end of the sampling needle 1 pierces the air bag valve and extends into the air bag. At this time, the area between the inner wall of the air bag and the outer wall of the battery sample is connected with the sampling needle 1.

[0028] S3, start the vacuum pump 4 to perform suction, and close valve B6 and valve C7 until the vacuum requirement is met. At this time, the air in the air bag, the sampling needle 1, and the pipeline and components between the sampling needle 1 and the valve C7 are evacuated.

[0029] S4. The sampling needle 1 is driven by the driving mechanism to continue to move toward the air bag valve 13, so that the front end of the sampling needle 1 continues to penetrate forward to the bulge position of the battery sample. Because the pipeline in the direction of valve B6 close to the sample tube 2 has been sucked to a vacuum state before penetration, under the action of the pressure difference, the bulging gas of the battery sample flows through the sampling needle 1 and valve A5 and then enters the sample tube 2 to realize the sampling and collection of the sample gas.

[0030] S5, after the delay control, close valve A5 to disconnect the sample tube 2 from the sampling needle 1, and then open valve B6. Since the pipeline between valve B6 and valve C7 has been sucked to a vacuum state before, when valve B6 is opened, the pipeline between valve A5 and valve C7 is connected. Under the action of the pressure difference, the sample gas collected in the sample tube 2 flows naturally and fills the pipeline. When the pressure detected by the pressure gauge 11 is stable, its detection value is the injection pressure.

[0031] S6. The gas passing through is quantitatively transferred to the gas chromatograph 12 for analysis through the injector 3.

[0032] According to the above working process, the automatic sampling and injection instrument for battery bulging gas can complete the whole process of sampling and injection of sample gas in sequence. Before sampling the battery bulging gas, all the air in the air bag and the system pipeline is first extracted and exhausted. The air bag plays a role of isolating the air for the battery sample, which can effectively avoid the influence of air mixing on the sampling accuracy. The whole sampling and transfer process is completed through pressure difference and valve control, which avoids the contamination of sample gas in the process of manual extraction and transfer, and is conducive to ensuring the accuracy of the test results.

[0033] The above is a single sampling and injection process of battery bulging gas, and multiple repeated injections can be achieved during implementation. That is, the sample is collected into the sample tube 2 for the first time. After the first injection, there is still sample gas in the sample tube 2. At this time, keep valve A5 and valve B6 closed, open valve C7 and vacuum pump 4 to evacuate until the vacuum degree requirement is met; then close valve C7 and vacuum pump 4, open valve B6, and the sample gas naturally flows from the sample tube 2 under the action of pressure difference and fills the pipeline of the injector 3; when the pressure detected by the pressure gauge 11 is stable, close valve B6, and its detection value is the injection pressure. The gas flowing through is quantitatively transferred to the gas chromatograph 12 for analysis through the injector 3, and repeated injection can be achieved.

[0034] The standard gas sampling and injection method includes the following steps: S1. Set the injection pressure and adjust the injection flow rate through the regulating mechanism 10, keep valve A5 and valve D8 in the closed state, open valve B6 and valve C7 to connect the pipeline between the vacuum pump 4 and the sample tube 2.

[0035] S2, start the vacuum pump 4 to suck, and close the valve C7 when the vacuum degree meets the requirement.

[0036] S3, open valve D8 to connect the pipeline from the standard gas cylinder 9 to valve C7. Since the pipeline between valve D8 and valve C7 is already in a vacuum state, the gas in the standard gas cylinder 9 will flow to the sampler 3 under the pressure difference, and close valve D8.

[0037] S4, open valve C7, and draw out the standard gas sample in the sample tube 2 under the suction of the vacuum pump 4. In this process, the standard gas sample will flow through the regulating mechanism 10 and the pressure gauge 11. Since the regulating mechanism 10 sets the flow rate or flow velocity, the standard gas sample can be controlled to be drawn out at a controlled, low flow rate or flow velocity. The pressure gauge 11 can detect the pressure value of the standard gas sample flowing through it in real time. When the pressure value detected by the pressure gauge 11 reaches the set injection pressure value, turn off the vacuum pump 4 or close valves B6 and C7 at the same time.

[0038] S5, quantitatively transferring the standard gas sample at the location thereof to the gas chromatograph 12 for analysis through the sample injector 3.

[0039] According to the above working process, the battery bulge gas automatic sampling and injection instrument can also complete the whole process of standard gas sampling, injection and analysis in sequence, and can realize pressure control when completing standard gas injection. In practical applications, only one bottle of high-concentration standard gas is needed. By injecting and analyzing at different pressure setting values, a standard curve can be quickly and automatically prepared. There is no need for a dynamic diluter or multiple bottles of standard gas with different concentrations, saving capital costs. In addition, since injection pressure control can be realized, if the concentration of a certain component of the sample gas is found to be too high during the analysis process after injection, the injection amount needs to be adjusted. For high concentrations, the pressure injection can be reduced, which is equivalent to sample dilution, and can effectively prevent the measurement error caused by sample overload.

[0040] like Figures 2 to 6 The embodiment shown in the figure is implemented in detail: The front end of the sampling needle 1 preferably adopts a side opening design, which can prevent the material fragments cut off when the sampling needle 1 pierces the soft elastic material in the air bag valve 13 from entering the sampling needle 1 and causing blockage. At the same time, the front end opening of the sampling needle 1 is set on the side to prevent the electrolyte in the battery sample from entering the sampling needle 1 and causing contamination when piercing the battery aluminum foil.

[0041] An air bag clamp is also provided, which includes an upper clamp 15, a lower clamp 16 and a lock 14. The upper clamp 15 is rotatably connected to the lower clamp 16. A clamping hole is formed when the upper clamp 15 and the lower clamp 16 are closed. The lock 14 is used to fix the upper clamp 15 and the lower clamp 16 when they are closed. After the battery is loaded into the air bag, the air bag valve 13 is inserted into the position of the clamping hole, and the upper clamp 15 and the lower clamp 16 are closed to complete the sample loading, which is convenient to operate.

[0042] A positioning groove 17 is processed at the circumferential position of the clamping hole in the air bag fixture, and a positioning platform 18 is arranged on the circumference of the air bag valve. When loading the sample, the positioning platform 18 is adapted to be arranged in the positioning groove 17 in a snap-in manner. On the one hand, this arrangement provides a reaction force so that the sampling needle 1 can smoothly penetrate into the air bag valve 13 to complete the air discharge in the air bag and the battery bulge gas sampling operation. On the other hand, it can complete the positioning when loading the sample, ensuring that the battery bulge surface is facing the front end of the sampling needle 1 after loading, and at the same time, it is convenient to determine the penetration distance of the sampling needle 1.

[0043] A body is also provided, and the aforementioned driving mechanism includes a first telescopic device 19 and a second telescopic device 20. The sampling needle 1 and the first telescopic device 19 are both fixedly mounted on the body, and the extended end of the first telescopic device 19 is fixedly connected to the second telescopic device 20, and the extended end of the second telescopic device 20 is fixedly connected to the lower clamping plate 16. Here, the sampling needle 1 is relatively fixed, and the lower clamping plate 16 can be driven to move by the extension of two telescopic devices (the telescopic devices can be selected from a variety of structural forms including cylinders, etc.), that is, after the lower clamping plate 16 (air bag clamp) is loaded with a sample, the aforementioned making the sampling needle 1 and the air bag valve 13 close to or away from each other can be achieved; it should be understood that in other embodiments, the air bag valve 13 can also be relatively fixed, and this function can also be achieved by driving the sampling needle 1 to move through the driving mechanism. In addition, the structural form of two telescopic devices is provided here, and the two actions of the sampling needle 1 piercing the air bag and piercing the battery bulge are respectively achieved by controlling the stroke of the first telescopic device 19 and the second telescopic device 20 respectively. It should be understood that other driving forms can also be selected in other embodiments to complete the above-mentioned action control.

[0044] Furthermore, the aforementioned valves A5, B6, C7 and D8 are all electrically controlled or pneumatically controlled valves, and a controller is also provided so that valves A5, B6, C7, D8, a driving mechanism, a vacuum pump 4 and an injector 3 are all electrically connected to the controller, thereby realizing fully automatic control of battery bulging gas sampling and analysis.

[0045] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. An automatic sampling and injection instrument for battery bulging gas, characterized in that: It includes a sampling needle, a sample tube, an injector, and a vacuum pump, wherein the sampling needle, the sample tube, the injector, and the vacuum pump are connected in sequence, a valve A is provided between the sampling needle and the sample tube, a valve B is provided between the sample tube and the injector, and a valve C is provided between the injector and the vacuum pump; It also includes a standard gas cylinder, a valve D, an adjusting mechanism and a pressure gauge, one end of the valve D is connected to the sample tube, and the other end of the valve D is connected to the standard gas cylinder. The adjusting mechanism and the pressure gauge are both arranged on the pipeline between the valve B and the valve C. The pressure gauge is used to detect the air pressure in the pipeline, and the adjusting mechanism is used to adjust the air flow rate or flow rate in the pipeline.

2. The automatic sampling and injection instrument for battery bulging gas according to claim 1, characterized in that: It also includes a gas chromatograph, which is connected to the injector, and the injector is used to quantitatively transfer the gas flowing through it to the gas chromatograph.

3. The automatic sampling and injection instrument for battery bulging gas according to claim 2, characterized in that: It also includes an airbag, an airbag valve and a driving mechanism, wherein the airbag is used to cover a battery to be tested, one end of the airbag valve is connected to the airbag, the end of the sampling needle away from valve A is the front end, and the front end of the sampling needle is arranged opposite to the end of the airbag valve away from the airbag, and the driving mechanism is used to drive the sampling needle and the airbag valve to approach or move away from each other. When the sampling needle and the airbag valve are close to each other, the front end of the sampling needle can pierce the airbag valve and extend into the airbag, and the front end of the sampling needle can also pierce the bulge of the battery to be tested in the airbag, and the airbag valve can achieve self-sealing when the sampling needle and the airbag valve are separated from each other.

4. The automatic sampling and injection instrument for battery bulging gas according to claim 3, characterized in that: A spacer made of soft and elastic material is arranged inside the air bag valve.

5. The automatic sampling and injection instrument for battery bulging gas according to claim 4, characterized in that: The sampling needle adopts a side opening design.

6. The automatic sampling and injection instrument for battery bulging gas according to claim 3, characterized in that: It also includes an air bag clamp, which includes an upper clamp, a lower clamp and a lock. The upper clamp is rotatably connected to the lower clamp, and a clamping hole is formed when the upper clamp and the lower clamp are closed. The air bag valve is inserted into the clamping hole, and the lock is used to fix the upper clamp and the lower clamp when they are closed.

7. The automatic sampling and injection instrument for battery bulging gas according to claim 6, characterized in that: A positioning groove is processed on the circumference of the clamping hole, and a positioning platform is arranged on the circumference of the air bag valve, and the positioning platform is adapted to be arranged in the positioning groove.

8. The automatic sampling and injection instrument for battery bulging gas according to claim 6 or 7, characterized in that: It also includes a body, the driving mechanism includes a first telescopic device and a second telescopic device, the sampling needle and the first telescopic device are both fixedly mounted on the body, the extended end of the first telescopic device is fixedly connected to the second telescopic device, and the extended end of the second telescopic device is fixedly connected to the lower clamp.

9. A method for automatically sampling and injecting gas from a battery bulge, characterized in that: The invention relates to an automatic sampling and injection instrument for battery bulging gas as described in claim 3, comprising a battery bulging gas sampling and injection method, wherein the battery bulging gas sampling and injection method comprises the following steps: S1. Place the battery sample into the air bag and seal the air bag, keep the valve D closed and open the valves A, B and C; S2, driving the sampling needle and the air bag valve to approach each other through the driving mechanism, so that the front end of the sampling needle pierces the air bag valve and extends into the air bag; S3, start the vacuum pump to suck, and close valve B and valve C when the vacuum degree meets the requirements; S4, driving the sampling needle and the air bag valve to approach each other through the driving mechanism, so that the front end of the sampling needle continues to penetrate forward to the bulge position of the battery sample; S5, closing the valve A after delay control, and then opening the valve B; S6. Quantitatively transfer the gas passing through the sample injector to the gas chromatograph.

10. The method for automatic sampling of battery bulging gas according to claim 9, characterized in that: The invention also includes a standard gas sampling and injection method, wherein the standard gas sampling and injection method comprises the following steps: S1, setting the injection pressure and adjusting the injection flow rate through the regulating mechanism, keeping the valve A and valve D both in a closed state, and opening the valve B and valve C; S2, start the vacuum pump to perform suction, and close the valve C when the vacuum degree meets the requirement; S3, opening the valve D, and then closing the valve D after delay control; S4, open the valve C, and when the pressure value detected by the pressure gauge reaches the set injection pressure value, turn off the vacuum pump or close the valves B and C at the same time; S5, quantitatively transferring the gas that meets the set pressure value flowing through the sample injector to the gas chromatograph.

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