CN219286499U - Secondary battery formation electrolyte return system - Google Patents

Abstract

The utility model discloses a secondary battery formation electrolyte backflow system which comprises a negative pressure source, a gas-liquid separator, a first switch, a second switch, a liquid collector, a normal pressure drying gas source, a third switch, a fourth switch and a flowmeter. The air outlet of the gas-liquid separator is communicated with a negative pressure source; the inlet of the first switch is communicated with the liquid injection port of the battery cell, the outlet of the first switch is communicated with the inlet of the second switch, and the outlet of the second switch is communicated with the air inlet of the gas-liquid separator; the liquid outlet of the gas-liquid separator is communicated with the first liquid inlet of the liquid collector; the inlet of the third switch is communicated with the liquid outlet of the gas-liquid separator, and the outlet is communicated with the first liquid inlet of the liquid collector; the inlet of the fourth switch is communicated with the liquid outlet of the liquid collector, and the outlet of the fourth switch is communicated with the outlet of the first switch; the inlet of the flowmeter is communicated with the outlet of the fourth switch, and the outlet is communicated with the outlet of the first switch. The electrolyte automatically flows back into the battery through negative pressure, so that the battery is prevented from swelling when the electrolyte flows back, and the reliability is high.

Description

Secondary battery formation electrolyte return system

technical field

The utility model relates to the technical field of battery formation, in particular to a secondary battery formation electrolyte backflow system.

Background technique

The main way to activate the performance of the secondary battery during the production process is to charge and activate the formation cabinet. During the negative pressure formation process of the secondary battery, the negative pressure formation equipment adjusts the gas inside the battery through the pressure control system, and the negative pressure vacuum The system extracts the gas generated during the formation process of the battery from the liquid injection port of the battery. During this process, a part of the electrolyte inside the battery will be pumped together with the above gas into a temporary storage container (residual liquid cup or waste liquid cup ), which will cause a waste of electrolyte.

In order to avoid the waste of electrolyte, a positive pressure drying system is generally used to fill the container with dry gas to reinject the electrolyte into the battery. However, it is difficult to control the amount of dry gas filled, which will cause excess dry gas to enter Inside the battery, the battery casing will bulge, be scrapped or even explode, causing great harm and loss.

Therefore, there is an urgent need to propose a secondary battery formation electrolyte reflow system to solve the above problems.

Utility model content

The utility model provides a reflow system for secondary battery formation electrolyte, which automatically reflows the electrolyte into the battery through negative pressure, avoids battery swelling when the electrolyte is reflowed, has simple structure and high working reliability.

For this purpose, the utility model adopts the following technical solutions:

Secondary battery formed electrolyte return system, including negative pressure source, gas-liquid separator, first switch, second switch, liquid collector, third switch, fourth switch and flow meter;

The negative pressure source is used to provide negative pressure, the gas outlet of the gas-liquid separator communicates with the negative pressure source, the inlet of the first switch communicates with the liquid injection port of the battery, and the outlet of the first switch communicates with the negative pressure source. It is connected with the inlet of the second switch, the outlet of the second switch is connected with the inlet of the gas-liquid separator, and the liquid outlet of the gas-liquid separator is connected with the first inlet of the liquid collector. The liquid port is connected, the liquid collector is provided with a pressure relief port, the pressure relief port is connected with the normal pressure dry gas source, and the inlet of the third switch is connected with the liquid outlet of the gas-liquid separator , the outlet of the third switch communicates with the first liquid inlet of the liquid collector, the inlet of the fourth switch communicates with the liquid outlet of the liquid collector, and the outlet of the fourth switch communicates with the liquid collector The outlet of the first switch is connected, the inlet of the flowmeter is connected with the outlet of the fourth switch, and the outlet of the flowmeter is connected with the outlet of the first switch.

Optionally, also include:

A proportional valve, the inlet of the proportional valve communicates with the gas outlet of the gas-liquid separator, and the outlet of the proportional valve communicates with the negative pressure source.

Optionally, also include:

A fifth switch, the inlet of the fifth switch communicates with the normal-pressure dry gas source, and the outlet of the fifth switch communicates with the pressure relief port.

Optionally, at least part of the structure of the liquid collector is transparent in color.

Optionally, also include:

a liquid level sensor arranged in the liquid collector;

Liquid supply equipment, communicated with the second liquid inlet of the liquid collector;

A control module, the liquid level sensor and the liquid supply equipment are both signal-connected to the control module, and the control module can control the liquid supply equipment to collect the liquid according to the liquid level signal transmitted by the liquid level sensor input electrolyte.

Optionally, the liquid level sensor is a contact liquid level sensor or a non-contact liquid level sensor.

Optionally, the negative pressure source includes a vacuum pump.

Optionally, the first switch is a solenoid valve; and/or:

The second switch is a solenoid valve; and/or:

The third switch is a solenoid valve; and/or:

The fourth switch is a solenoid valve;

The secondary battery formation electrolyte return system also includes a control module, and the flow meter, the first switch, the second switch, the third switch and the fourth switch are all connected to the control module The control module can control the opening and closing of the first switch, the second switch, the third switch and the fourth switch according to the flow signal of the flow meter.

Optionally, the fifth switch is a ventilation valve.

The beneficial effects of the utility model:

The utility model provides a secondary battery formation electrolyte return system, comprising a negative pressure source, a gas-liquid separator, a first switch, a second switch, a liquid collector, a normal pressure dry gas source, a third switch, and a fourth switch and flow meter. When the battery is forming under negative pressure, the first switch, the second switch, and the third switch are turned on, and the fourth switch is turned off. The gas carrying the electrolyte inside the battery enters the gas-liquid separator under the action of the negative pressure source, and the gas-liquid separation The gas is separated from the electrolyte, the gas is discharged through the negative pressure source, and the electrolyte flows into the liquid collector for storage. At this time, the inside of the battery is in a negative pressure environment; after the battery completes the negative pressure formation, turn off the second switch and the third switch, Turn on the fourth switch and the first switch, since the liquid collector is always in the normal pressure state, therefore, the electrolyte in the liquid collector can automatically flow into the battery in the negative pressure state, avoiding the waste of the electrolyte, and at the same time there will be no The risk of external gas entering the inside of the battery, avoiding battery swelling, is conducive to protecting the battery.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings that need to be used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only the illustrations of the present invention. For some embodiments, those of ordinary skill in the art can also obtain other drawings according to the content of the embodiments of the present invention and these drawings without any creative effort.

Fig. 1 is a schematic structural diagram of a reflow system for forming an electrolyte of a secondary battery provided by an embodiment of the present invention.

In the picture:

1. Negative pressure source; 2. Gas-liquid separator; 3. First switch; 4. Second switch; 5. Battery; 6. Liquid collector; 7. Normal pressure dry gas source; 8. Third switch; 9 , the fourth switch; 10, the flow meter; 11, the proportional valve; 12, the fifth switch; 13, the liquid supply equipment.

Detailed ways

Below in conjunction with accompanying drawing and embodiment the utility model is described in further detail. It can be understood that the specific embodiments described here are only used to explain the utility model, rather than limit the utility model. In addition, it should be noted that, for the convenience of description, only some structures related to the present utility model are shown in the drawings but not all structures.

In the description of the present utility model, unless otherwise clearly stipulated and limited, the terms "connected", "connected" and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or a Integral; it can be mechanically or electrically connected; it can be directly connected or indirectly connected through an intermediary, and it can be the internal communication of two components or the interaction relationship between two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present utility model in specific situations.

In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, and may also include the first and second features being in direct contact with each other. The features are not in direct contact but through another feature between them. Moreover, "above", "above" and "above" the first feature on the second feature include that the first feature is directly above and obliquely above the second feature, or simply means that the first feature is horizontally higher than the second feature. "Below", "beneath" and "under" the first feature to the second feature include that the first feature is directly below and obliquely below the second feature, or simply means that the first feature has a lower level than the second feature.

In the description of this embodiment, the terms "up", "down", "left", "right" and other orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operations. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in description, and have no special meaning.

This embodiment provides a reflow system for secondary battery formation electrolyte, which automatically reflows the electrolyte into the battery 5 through negative pressure. Compared with the positive pressure drying system used in the prior art to make the reflow of the electrolyte, the reflow of the electrolyte can be avoided. When the battery 5 bulges, the structure is simple and the work reliability is high.

Specifically, as shown in Figure 1, the secondary battery formation electrolyte return system includes a negative pressure source 1, a gas-liquid separator 2, a first switch 3, a second switch 4, a liquid collector 6, and a dry gas source at normal pressure 7. The third switch 8, the fourth switch 9 and the flow meter 10. Wherein, the negative pressure source 1 is used to provide negative pressure, and the negative pressure source 1 is optional but not limited to a vacuum pump. The gas outlet of the gas-liquid separator 2 communicates with the negative pressure source 1, and the gas-liquid separator 2 is used to separate the electrolyte from the humid gas carrying the electrolyte. The inlet of the first switch 3 is connected with the liquid injection port of the battery 5, the outlet of the first switch 3 is connected with the inlet of the second switch 4, the outlet of the second switch 4 is connected with the air inlet of the gas-liquid separator 2, and the negative battery is turned on. The pressure source 1 and the gas carrying the electrolyte in the battery 5 are drawn out and enter the gas-liquid separator 2 to wait for separation. The liquid outlet of the gas-liquid separator 2 communicates with the first liquid inlet of the liquid collector 6, and the liquid collector 6 is provided with a pressure relief port, and the pressure relief port communicates with the normal pressure dry gas source 7, and the gas-liquid separator 2 The separated electrolyte is stored in the liquid collector 6. In order to ensure that the electrolyte can flow smoothly into the liquid collector 6 and not be affected by the interference of external humid gas to affect the quality of the electrolyte, the liquid collector 6 is connected to the liquid collector 6 through the pressure relief port. The normal pressure dry gas source 7 is connected, and the normal pressure dry gas source 7 can keep the electrolyte in the liquid collector 6 at normal pressure, and because the normal pressure dry gas source 7 is normal pressure, it will not automatically enter the battery 5 to avoid The battery 5 is inflated with air. The inlet of the third switch 8 communicates with the liquid outlet of the gas-liquid separator 2 , and the outlet of the third switch 8 communicates with the first liquid inlet of the liquid collector 6 . The inlet of the fourth switch 9 communicates with the liquid outlet of the liquid collector 6 , and the outlet of the fourth switch 9 communicates with the outlet of the first switch 3 . The inlet of the flowmeter 10 communicates with the outlet of the fourth switch 9 , and the outlet of the flowmeter 10 communicates with the outlet of the first switch 3 .

The working process of the above-mentioned secondary battery formation electrolyte return system is as follows:

In the negative pressure forming stage of the battery 5: open the first switch 3, the second switch 4 and the third switch 8, close the fourth switch 9, under the action of the negative pressure source 1, the gas carrying the electrolyte is discharged from the battery 5 and Enter the gas-liquid separator 2 to be separated, the separated gas is discharged through the negative pressure source 1, the electrolyte flows into the liquid collector 6 for storage, and the inside of the battery 5 is in a negative pressure state.

Electrolyte reflux stage: At this time, the negative pressure formation of the battery 5 is completed, the first switch 3 and the fourth switch 9 are turned on, the second switch 4 and the third switch 8 are turned off, and since the liquid collector 6 is at normal pressure, the pressure is greater than that of the battery 5 internal pressure, therefore, the electrolyte in the liquid collector 6 will automatically flow back into the battery 5, and the flowmeter 10 will display the amount of electrolyte flowing back into the battery 5, when the flowmeter 10 no longer changes, it indicates that the liquid is collected The electrolyte solution in the device 6 no longer flows back into the battery 5. At this time, if the flowmeter 10 shows that the electrolyte solution flowing back into the battery 5 reaches a preset value, the backflow is terminated. The preset value can be obtained according to experiments. In this embodiment, the preset value is 6g-8g; if the electrolyte solution displayed by the flowmeter 10 does not reach the preset value, then start the negative pressure source 1 again, open the first switch 3, the second Switch 4 and the third switch 8, close the fourth switch 9, make the inside of the battery 5 be in a negative pressure state again, then close the second switch 4 and the third switch 8, open the fourth switch 9, make the liquid in the liquid collector 6 Continue to flow back into the battery 5, and repeat this process for many times until the electrolyte solution flowing back into the battery 5 reaches a preset value.

The secondary battery formed electrolyte return system provided in this embodiment automatically returns the electrolyte in the liquid collector 6 to the battery 5 through the negative pressure inside the battery 5 , avoiding waste of the electrolyte and reducing the material cost of the battery 5 . Moreover, it can be guaranteed that no outside gas will enter the battery 5 , avoiding the damage of the battery 5 due to inflation and swelling, which is beneficial to protect the battery 5 .

Further, in this embodiment, the first switch 3 can be but not limited to a solenoid valve, similarly, the second switch 4 can be but not limited to a solenoid valve, the third switch 8 can be but not limited to a solenoid valve, and the fourth switch 8 can be but not limited to a solenoid valve. The switch 9 can be, but not limited to, a solenoid valve. The above-mentioned secondary battery formation electrolyte return system also includes a control module, the flow meter 10, the first switch 3, the second switch 4, the third switch 8 and the fourth switch 9 are all connected with the control module. Module signal connection, the control module can control the opening and closing of the first switch 3, the second switch 4, the third switch 8 and the fourth switch 9 according to the flow signal of the flow meter 10, and then realize the above-mentioned secondary battery formation electrolyte return system intelligent control. Since the electrolyte is corrosive, the first switch 3 , the second switch 4 , the third switch 8 and the fourth switch 9 can be made of corrosion-resistant materials.

It should be noted that the specific forms of the "control module" in this application include but are not limited to PLC and the like.

Optionally, the secondary battery formation electrolyte return system further includes a proportional valve 11 , the inlet of the proportional valve 11 communicates with the gas outlet of the gas-liquid separator 2 , and the outlet of the proportional valve 11 communicates with the negative pressure source 1 . By setting the proportional valve 11, the air extraction volume of the negative pressure source 1 can be flexibly adjusted according to the required negative pressure in the battery 5, reducing the risk of excessive air extraction and improving the working stability of the negative pressure source 1.

Optionally, the secondary battery formation electrolyte return system further includes a fifth switch 12, the inlet of the fifth switch 12 communicates with the normal pressure dry gas source 7, and the outlet of the fifth switch 12 communicates with the pressure relief port. When the above-mentioned secondary battery formation electrolyte return system is working, the fifth switch 12 is in a normally open state, and when the above-mentioned secondary battery formation electrolyte return system or system maintenance is not needed, the fifth switch 12 can be closed to avoid normal pressure drying Waste of air source 7. The fifth switch 12 is optional but not limited to a vent valve.

Preferably, in order to facilitate the observation of the amount of electrolyte in the liquid collector 6 , at least part of the structure of the liquid collector 6 is transparent. The liquid collector 6 can be a residual liquid cup or a waste liquid cup.

It is worth noting that, when the above-mentioned secondary battery formation electrolyte return system is initially used, there may be part of the electrolyte in the liquid collector 6, or there may be no electrolyte. If there is no electrolyte in the liquid collector 6 initially, then initially The battery 5 performing negative pressure formation may not return the electrolyte, and the electrolyte stored in the liquid collector 6 may be used by the next batch of batteries 5 performing negative pressure formation, as long as the electrolyte is not wasted.

Further, the above-mentioned reflow system for secondary battery formation electrolyte also includes a liquid level sensor (not shown in the figure), a liquid supply device 13 and a control module (not shown in the figure), and the liquid level sensor is arranged in the liquid collector 6 , for real-time detection of the liquid level of the electrolyte. The liquid collector 6 is also provided with a second liquid inlet, and the liquid supply device 13 communicates with the second liquid inlet of the liquid collector 6 , and the liquid supply device 13 can deliver electrolyte solution to the liquid collector 6 . Both the liquid level sensor and the liquid supply device 13 are connected to the control module with signals, and the control module can control the liquid supply device 13 to input electrolyte for the liquid collector 6 according to the liquid level signal transmitted by the liquid level sensor. By arranging the liquid supply device 13 and the liquid level sensor, it can be ensured that the electrolyte in the liquid collector 6 remains sufficient all the time, thereby ensuring that the battery 5 after negative pressure formation can return a certain amount of electrolyte (that is, when the electrolyte in the liquid collector 6 When the amount of electrolyte solution can not meet the electrolyte return flow required by the battery 5, the liquid collector 6 can be replenished by setting the liquid supply device 13, so as to meet the needs of the battery 5 that can be returned to the battery 5 after negative pressure formation. Electrolyte return flow), which is conducive to mass production. Optionally, the liquid level sensor can be a contact liquid level sensor or a non-contact liquid level sensor, which can be set according to actual needs.

Apparently, the above-mentioned embodiments of the present utility model are only examples for clearly illustrating the present utility model, rather than limiting the implementation manner of the present utility model. Various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. It is not necessary and impossible to exhaustively list all the implementation manners here. All modifications, equivalent replacements and improvements made within the spirit and principles of the utility model shall be included in the protection scope of the claims of the utility model.

Claims (9)

1. The secondary battery is formed into an electrolyte return system, which is characterized in that it includes a negative pressure source (1), a gas-liquid separator (2), a first switch (3), a second switch (4), a liquid collector (6 ), normal pressure drying gas source (7), the third switch (8), the fourth switch (9) and flow meter (10); The negative pressure source (1) is used to provide negative pressure, the gas outlet of the gas-liquid separator (2) communicates with the negative pressure source (1), and the inlet of the first switch (3) is connected to the battery ( 5), the outlet of the first switch (3) is connected with the inlet of the second switch (4), and the outlet of the second switch (4) is connected with the gas-liquid separator (2) ), the liquid outlet of the gas-liquid separator (2) communicates with the first liquid inlet of the liquid collector (6), and the liquid collector (6) is provided with a pressure relief The pressure relief port communicates with the normal pressure dry gas source (7), the inlet of the third switch (8) communicates with the liquid outlet of the gas-liquid separator (2), and the third The outlet of the switch (8) communicates with the first liquid inlet of the liquid collector (6), the inlet of the fourth switch (9) communicates with the liquid outlet of the liquid collector (6), and the The outlet of the fourth switch (9) communicates with the outlet of the first switch (3), the inlet of the flow meter (10) communicates with the outlet of the fourth switch (9), and the flow meter (10) The outlet of the first switch (3) communicates with the outlet. 2. The secondary battery formation electrolyte return system according to claim 1, further comprising: A proportional valve (11), the inlet of the proportional valve (11) communicates with the gas outlet of the gas-liquid separator (2), and the outlet of the proportional valve (11) communicates with the negative pressure source (1). 3. The secondary battery formation electrolyte return system according to claim 1, further comprising: A fifth switch (12), the inlet of the fifth switch (12) communicates with the normal pressure dry gas source (7), and the outlet of the fifth switch (12) communicates with the pressure relief port. 4. The reflow system for secondary battery formation electrolyte according to claim 1, characterized in that at least part of the structure of the liquid collector (6) is transparent. 5. The secondary battery formation electrolyte reflux system according to any one of claims 1-4, further comprising: A liquid level sensor is arranged in the liquid collector (6); Liquid supply equipment (13), communicated with the second liquid inlet of the liquid collector (6); A control module, the liquid level sensor and the liquid supply equipment (13) are both signal-connected to the control module, and the control module can control the liquid supply equipment (13) according to the liquid level signal transmitted by the liquid level sensor ) input electrolyte for the liquid collector (6). 6 . The secondary battery formation electrolyte return system according to claim 5 , wherein the liquid level sensor is a contact liquid level sensor or a non-contact liquid level sensor. 7. The reflow system for formation of secondary battery electrolyte according to any one of claims 1-4, characterized in that the negative pressure source (1) includes a vacuum pump. 8. The secondary battery formation electrolyte return system according to any one of claims 1-4, characterized in that the first switch (3) is a solenoid valve; and/or: The second switch (4) is a solenoid valve; and/or: The third switch (8) is a solenoid valve; and/or: The fourth switch (9) is an electromagnetic valve; The secondary battery formation electrolyte return system further includes a control module, the flow meter (10), the first switch (3), the second switch (4), the third switch (8) and The fourth switch (9) is connected with the control module signal, and the control module can control the first switch (3), the second switch (4) according to the flow signal of the flow meter (10). ), the opening and closing of the third switch (8) and the fourth switch (9). 9. The reflow system for formation of secondary battery electrolyte according to claim 3, characterized in that the fifth switch (12) is a vent valve.

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