Battery formation gas measurement device

Abstract

The utility model relates to the manufacture of secondary battery, especially battery formation gas production measuring device. The utility model provides a kind of brand-new battery formation gas production measuring device, and the sealed water collection gas bottle that is communicated with battery exhaust port can completely collect the gas production in the process of battery formation, make gas production expel the water in sealed water collection gas bottle to open mouth weighing bottle, by real-time weighing the water in open mouth weighing bottle, can measure gas production, real-time monitoring gas production situation. The whole device can conveniently and accurately obtain gas production rate and gas production, so as to monitor and analyze gas production situation, capture battery high gas production stage, avoid battery swelling and other process risks by reducing current or increasing negative pressure and other ways, provide new proof direction for battery process problem troubleshooting through the battery gas production curve generated.

Description

Technical Field

[0001] This utility model relates to the manufacture of secondary batteries, and more particularly to a device for measuring the gas production during battery formation. Background Technology

[0002] With the rapid development of the new energy industry, the demand for batteries is increasing, and users are placing higher demands on battery safety and capacity, which in turn puts higher requirements on battery manufacturing. Battery formation is a crucial process in battery manufacturing. Gas is generated during battery formation, and the gas production rate and quantity reflect the battery formation data, providing a reference for formulating formation recipes in the development of new battery cells. However, currently, gas production during battery formation is either collected by gasbags or naturally released, and the gas production rate and quantity are not monitored or measured; therefore, there is no dedicated measuring device for this purpose. Utility Model Content

[0003] The purpose of this invention is to provide a battery formation gas generation measurement device to solve the problem that existing technologies, which collect gas generation through airbags or directly release gas generation, cannot monitor the gas generation rate and amount in real time and cannot provide data support for formation formulation.

[0004] The battery formation gas generation measuring device of this utility model includes a sealed water-filled gas collecting bottle connected to the battery exhaust port via a pipeline, and an open weighing bottle connected to the sealed water-filled gas collecting bottle via a pipeline for holding the water expelled by the gas in the sealed water-filled gas collecting bottle. The open weighing bottle is equipped with an online weighing device for weighing its body and the water inside the bottle. One end of the pipeline connecting the sealed water-filled gas collecting bottle and the open weighing bottle is connected to the sealed water-filled gas collecting bottle near the bottom, and the other end is connected to the top of the open weighing bottle to prevent the water in the sealed water-filled gas collecting bottle from flowing naturally into the open weighing bottle.

[0005] This invention provides a novel battery formation gas generation measurement device. A sealed water-filled gas collecting bottle connected to the battery's exhaust port can completely collect the gas generated during the battery formation process. The generated gas displaces the water in the sealed bottle into an open weighing bottle. By weighing the water in the open weighing bottle in real time, the gas generation rate can be calculated, allowing for real-time monitoring of the gas generation situation. The entire device can conveniently and accurately obtain the gas generation rate and amount, facilitating the monitoring and analysis of the gas generation situation. It can capture the high gas generation stage of the battery and, by reducing the current or increasing the negative pressure, avoid process risks such as battery swelling. The generated battery gas generation curve provides new directions for troubleshooting battery process problems. Attached Figure Description

[0006] Figure 1 This is a schematic diagram of the battery formation gas generation measuring device of this utility model in use. Figure 2 This is a schematic diagram of the cylindrical body of the sealed water-containing gas collecting bottle in this utility model.

[0007] In the diagram: 1. Battery; 2. Gas supply line; 3. Sealed water-filled gas collecting bottle; 4. Drainage line; 5. Open weighing bottle; 6. Online weighing device; 7. Computer; 8. Electrolyte separator; 9. Bottle cap; 30. Cylindrical bottle body; 31. Connecting pipe. Detailed Implementation

[0008] This invention addresses the current practice in battery formation where generated gases are either directly vented or temporarily collected via airbags, without analyzing the gas production data to inform battery and formation process analysis. It provides a measuring device for online collection and measurement of gas production during battery formation. This device monitors the gas production rate and quantity in real time, enabling monitoring and analysis of the gas production situation. On one hand, it allows for proactive control during high gas production stages, preventing process risks such as battery swelling. On the other hand, the generated battery gas production curve provides new directions for troubleshooting battery process issues. Furthermore, it provides data reference for formulating formation recipes during the development of new battery cell products.

[0009] Specifically, the specific implementation of the battery formation gas generation measuring device of this utility model is as follows: In one implementation, such as Figure 1 As shown, the battery formation gas generation measuring device mainly includes a sealed water-filled gas collecting bottle 3, an open weighing bottle 5, a gas supply line 2, and a drainage line 4. The sealed water-filled gas collecting bottle 3 is used to hold water and collect the gas generated during the battery formation process. It is a sealed bottle with both gas-tight and liquid-tight properties. The sealed water-filled gas collecting bottle 3 is connected to the exhaust port of the battery 1 through the gas supply line 2, allowing the gas generated during the battery formation process to enter the bottle. The open weighing bottle 5 is an open bottle body equipped with an online weighing device 6. The online weighing device 6 can be an integral structure with the open bottle body, i.e., a weighing module integrated into the bottom or periphery of the open bottle body to form the online weighing device 6; or the online weighing device 6 can be independent of the open bottle body, and can be an electronic scale, allowing the open bottle body to be placed on its weighing plane. The open weighing bottle 5 is connected to the sealed water-containing gas collecting bottle 3 through the drain pipe 4, and the connection position of the drain pipe 4 and the sealed water-containing gas collecting bottle 3 is located near the bottom of the sealed water-containing gas collecting bottle 3, while the connection position of the drain pipe 4 and the open weighing bottle 5 is located at the top mouth of the open weighing bottle 5.

[0010] During the battery formation process, the generated gas enters the sealed water-filled gas collecting bottle 3 through the gas supply pipe 2. It accumulates at the top of the bottle, above the water surface, increasing the pressure and displacing water from the bottle. This displaced water flows through the drain pipe 4 into the open weighing bottle 5. As more gas enters the sealed water-filled gas collecting bottle 3, more water is displaced and replaced in the open weighing bottle 5. The online weighing device 6 installed in the open weighing bottle 5 measures the weight change in real time. The online weighing device 6 communicates with a computer 7 via a communication cable or wireless communication module, transmitting the monitored weight data to the computer 7. The computer 7 calculates the volume change of water in the open weighing bottle 5, thereby determining the change in gas volume in the sealed water-filled gas collecting bottle 3, ultimately yielding the gas production rate and quantity.

[0011] The connection point between the drain pipe 4 and the sealed water-filled gas collecting bottle 3 is located near the bottom of the bottle 3, preferably at a height of 8mm-13mm from the bottom. This allows for greater utilization of the water in the sealed water-filled gas collecting bottle 3 to replace the generated gas and facilitates the connection between the drain pipe and the bottle body. If the water level in the sealed water-filled gas collecting bottle 3 is higher than the connection point between the drain pipe 4 and the open weighing bottle 5, then based on the principle of communicating vessels, the water in the sealed water-filled gas collecting bottle 3 will automatically flow into the open weighing bottle 5. This is clearly not the desired outcome of this invention. Therefore, the connection point between the drain pipe 4 and the open weighing bottle 5 is located at the top opening of the open weighing bottle 5. This ensures that even when the water level in the sealed water-filled gas collecting bottle 3 is high, it remains below the connection point between the drain pipe 4 and the open weighing bottle 5, thereby increasing the water volume in the sealed water-filled gas collecting bottle 3 and thus increasing the gas collection capacity of the sealed water-filled gas collecting bottle 3.

[0012] In a preferred embodiment, the connection point between the gas supply pipeline 2 and the sealed water-filled gas collecting bottle 3 is also located near the upper end of the sealed water-filled gas collecting bottle 3, so that the connection point is above the water surface after water is added to the sealed water-filled gas collecting bottle 3. This avoids backflow of water in the sealed water-filled gas collecting bottle 3 along the gas supply pipeline 2, and also allows the generated gas to enter the sealed water-filled gas collecting bottle 3 without passing through the water in the sealed water-filled gas collecting bottle 3, thus facilitating gas entry.

[0013] The shape of the sealed water-containing gas collecting bottle 3 is not particularly limited; it can be a cylindrical bottle body with a cap 9 installed on the top to achieve a seal. In a preferred embodiment, the top of the sealed water-containing gas collecting bottle 3 is frustum-shaped, and the inlet and outlet of the sealed water-containing gas collecting bottle 3 are located on a conical surface, with a cap 9 sealed at the inlet and outlet. This results in a smaller diameter for the inlet and outlet, facilitating a better gas seal. The sealed water-containing gas collecting bottle 3 can be a one-piece molded glass bottle, or in another embodiment, the sealed water-containing gas collecting bottle includes a cylindrical bottle body 30 (e.g., Figure 2 (As shown) and a frustum-shaped top cover, which are connected by a flange seal, or when both the cylindrical bottle body and the frustum-shaped top cover are made of metal, they are connected by full welding seal, which facilitates the manufacture of a sealed water-filled gas collecting bottle.

[0014] Based on this, the pipeline connecting the exhaust port of battery 1 to the sealed water-filled gas collecting bottle 3 is connected at a height close to the bottom of the truncated cone. In fact, when the sealed water-filled gas collecting bottle 3 and the open weighing bottle 5 are at the same horizontal height, it is a better embodiment to have the connection position of the gas supply pipeline 2 to the sealed water-filled gas collecting bottle 3 and the connection position of the drain pipeline 4 to the open weighing bottle 5 at the same horizontal height.

[0015] The sealing water-filled gas collecting bottle has a connecting pipe 31 that connects to the gas supply line and the drain line, serving as a pipe joint. When the sealing water-filled gas collecting bottle is made of glass, the connecting pipe 31 is integrally formed with the bottle body. When the sealing water-filled gas collecting bottle is made of metal, a radially penetrating orifice is provided on the bottle body at the corresponding pipe joint position. The connecting pipe 31 is welded to the outside of the bottle body at the corresponding orifice position, forming the pipe joint. Both the water / gas line and the drain line can be made of rubber hoses, which are readily available and facilitate positional changes between the sealing water-filled gas collecting bottle and the battery or open weighing bottle. The rubber hose is fitted onto the connecting pipe with an interference fit, ensuring the reliability and sealing of the connection through clamping force. In a preferred embodiment, the length of the connecting tube extending out of the bottle body is between 12mm and 18mm. This ensures that the connecting tube is not damaged by bumps during use due to excessive extension length, and also ensures that the connecting tube and the rubber hose have a certain interference fit length, guaranteeing the reliability and sealing of the connection, so that it can withstand water pressure and gas pressure when there is a high liquid level in the sealed water-filled gas collecting bottle.

[0016] During the battery gas generation process, some electrolyte will flow out. In a preferred embodiment, an electrolyte separator 8 is connected in series on the gas supply line 2 to prevent electrolyte from entering the sealed water-filled gas collection bottle 3 and affecting the liquid level change inside.

[0017] Before using the battery formation gas production measuring device of this utility model, water is filled into the sealed water-filled gas collecting bottle 3 until it is below the connection point between the gas supply pipeline 2 and the sealed water-filled gas collecting bottle 3. The open weighing bottle 5 is emptied and its weight data is zeroed. The sealed water-filled gas collecting bottle 3 remains sealed, while the open weighing bottle 5 remains open, communicating with the atmosphere. At the start of the test, battery 1 begins to produce gas, which accumulates above the liquid level in the sealed water-filled gas collecting bottle 3. As the gas increases, it pushes the liquid level downwards, and water flows through the drain pipe to the open weighing bottle 5. As more and more gas accumulates in the sealed water-filled gas collecting bottle 3, more and more water is simultaneously replaced in the open weighing bottle 5. During this process, the weight change of the open weighing bottle 5 is monitored by the online weighing device 6, and the change in the water volume of the open weighing bottle 5 can be calculated. This allows us to obtain the change in the gas increment in the sealed water-filled gas collecting bottle 3, which is the amount of gas produced by the battery.

[0018] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. A battery formation gas generation measuring device, characterized in that, It includes a sealed water-filled gas collecting bottle connected to the battery vent via a pipeline, and an open weighing bottle connected to the sealed water-filled gas collecting bottle via a pipeline for holding water that has been expelled by gas in the sealed water-filled gas collecting bottle. The open weighing bottle is equipped with an online weighing device for weighing its body and the water inside the bottle. One end of the pipeline connecting the sealed water-filled gas collecting bottle and the open weighing bottle is connected to the sealed water-filled gas collecting bottle near the bottom, and the other end is connected to the top of the open weighing bottle to prevent water in the sealed water-filled gas collecting bottle from flowing naturally into the open weighing bottle.

2. The battery formation gas generation measuring device according to claim 1, characterized in that, The pipe connecting the battery vent to the sealed water-filled gas collecting bottle is located near the top of the sealed water-filled gas collecting bottle.

3. The battery formation gas generation measuring device according to claim 1, characterized in that, The top of the sealed water-filled gas collecting bottle is truncated cone-shaped, and the inlet and outlet of the sealed water-filled gas collecting bottle are located on the conical surface, with bottle caps installed at the inlet and outlet.

4. The battery formation gas generation measuring device according to claim 3, characterized in that, The pipe connecting the battery vent to the sealed water-filled gas collecting bottle is located at a height close to the bottom of the truncated cone.

5. The battery formation gas generation measuring device according to claim 3, characterized in that, The sealed water-containing gas collecting bottle consists of a cylindrical body and a frustum-shaped top cover, which are connected by a flange seal or a full weld seal.

6. The battery formation gas generation measuring device according to any one of claims 1-5, characterized in that, The pipe interface of the sealed water-filled gas collecting bottle should be 8mm to 13mm away from the bottom of the bottle.

7. The battery formation gas generation measuring device according to any one of claims 1-5, characterized in that, The pipeline is a rubber hose, and it is connected to the sealed water-containing gas collecting bottle through a pipeline joint installed on the bottle body with an interference fit. The pipeline joint is a connecting pipe welded to the bottle body and extending horizontally.

8. The battery formation gas generation measuring device according to claim 7, characterized in that, The protruding length of the connecting tube is between 12mm and 18mm to ensure the interference fit between the rubber hose and the connecting tube.

9. The battery formation gas generation measuring device according to any one of claims 1-5, characterized in that, The online weighing device communicates with a computer via a communication cable or wireless communication module and transmits the real-time monitored weight data to the computer.

10. The battery formation gas generation measuring device according to any one of claims 1-5, characterized in that, An electrolyte separator is connected in series on the pipeline connecting the battery exhaust port and the sealed water-filled gas collecting bottle to prevent electrolyte from entering the sealed water-filled gas collecting bottle.

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