Square battery cell exhaust cover plate structure

Abstract

According to the square battery cell exhaust cover plate structure, a cover plate body covers a square battery cell; the gas storage bin is a cavity which is formed by protruding the cover plate body in the direction away from the square battery cell and used for containing gas, the gas storage bin is arranged at the bottom of the gas storage bin in a penetrating mode and communicated with the square battery cell, and the positioning and pressing structure is arranged on the top inner wall, opposite to the through hole, of the gas storage bin and comprises a spring block used for pressing; the sealing plug is fixedly connected with the spring block and is pressed by the spring block to seal the through hole; the at least one auxiliary exhaust valve is arranged on the top inner wall, opposite to the through hole, of the gas storage bin and can switch connection and disconnection between the gas storage bin and the external environment; the anti-explosion valve is arranged on the cover plate body, and a second pressure threshold value for opening the anti-explosion valve is larger than or equal to a first pressure threshold value for opening the auxiliary exhaust valve. According to the structure, the problems that the shell is expanded due to accumulated gas production in the normal battery cell use process and the exhaust valve cannot be opened and the occupied space is large are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a square battery cell exhaust cover plate structure. Background Art

[0002] With the rapid development of technology and the transformation of the energy structure, lithium batteries, as an efficient and environmentally friendly energy storage and supply method, have been widely used in fields such as electric vehicles, mobile devices, and energy storage systems.

[0003] Square battery cells are widely used in many fields due to their high energy density, high structural strength, and reliable sealing. However, due to this, during long-term operation or extreme failure of square battery cells, the gas generated inside will cause the battery cells to bulge, and in severe cases, even explosion accidents may occur, posing great potential risks. Even if no explosion accident occurs, the inability to discharge the internally generated gas will also cause the structural components to bear greater stress, or cause the risk of misalignment of the internal core package electrode structure.

[0004] The explosion-proof valves of the prior art cannot solve the problem of shell bulging caused by the cumulative gas generation during the normal use of battery cells; in addition, because the explosion-proof valve is a one-time destructive design, its structure is damaged after opening and cannot be used normally; how to control the stability and high precision of the valve opening pressure for the explosion-proof valve that causes a thin layer structure is still a challenge in the industry. The exhaust pipes of the prior art occupy too much external space of the battery cell and require the arrangement of exhaust pipelines, which not only affects the internal use space of the whole package but also reduces the strength reliability after grouping; in addition, because the exhaust pipe is directly connected to the original battery cell exhaust valve, in the case of extreme failure and out-of-control inside the battery cell, it may cause the main exhaust valve to fail to open normally, resulting in safety risks.

[0005] The above information disclosed in the background art section is only used to enhance the understanding of the background of the present utility model, and thus may include information that does not constitute the prior art known to those of ordinary skill in the art. Summary of the Utility Model

[0006] The purpose of the present utility model is to provide a square battery cell exhaust cover plate structure, which can solve the problem of shell bulging caused by the cumulative gas generation during the normal use of battery cells and avoid the problems of the exhaust valve being unable to open and large space occupation.

[0007] In order to achieve the above purpose, the present utility model provides the following technical solutions:

[0008] A square battery cell exhaust cover plate structure of the present utility model includes:

[0009] A cover plate body, which is covered on the square battery cell;

[0010] At least one exhaust structure, which is arranged on the cover plate body, and the exhaust structure includes,

[0011] A gas storage chamber, which is a cavity formed by the cover plate body protruding away from the square battery cell for accommodating gas.

[0012] A through hole, which is provided at the bottom of the gas storage chamber and communicates with the square battery cell.

[0013] A positioning and pressing structure, which is provided on the top inner wall of the gas storage chamber relative to the through hole. The positioning and pressing structure includes a spring block for pressing.

[0014] A sealing plug, which is fixedly connected to the spring block and presses and seals the through hole via the spring block.

[0015] At least one auxiliary exhaust valve, which is provided on the top inner wall of the gas storage chamber relative to the through hole and can switch the on-off between the gas storage chamber and the external environment.

[0016] An explosion-proof valve, which is provided on the cover plate body and the second pressure threshold for the explosion-proof valve to open is greater than or equal to the first pressure threshold for the auxiliary exhaust valve to open.

[0017] In the described square battery cell exhaust cover plate structure, the first pressure threshold is greater than the pressure exerted by the spring block.

[0018] In the described square battery cell exhaust cover plate structure, the cover plate body further includes a pole column and a liquid injection hole.

[0019] In the described square battery cell exhaust cover plate structure, the height of the protrusion of the gas storage chamber is flush with the height of the pole column.

[0020] In the described square battery cell exhaust cover plate structure, the explosion-proof valve is located at the middle position of the high plate body, and at least two exhaust structures are located on both sides of the explosion-proof valve.

[0021] In the described square battery cell exhaust cover plate structure, the positioning and pressing structure and the through hole are both provided on the central axis of the gas storage chamber and are arranged oppositely.

[0022] In the described square battery cell exhaust cover plate structure, the positioning and pressing structure further includes a side wall for positioning and guiding the spring block.

[0023] In the described square battery cell exhaust cover plate structure, the side wall extends vertically towards the through hole.

[0024] In the described square battery cell exhaust cover plate structure, the side wall is a cylindrical wall.

[0025] In the described square battery cell exhaust cover plate structure, the sealing plug is a truncated cone structure.

[0026] In the above technical solution, a square battery cell exhaust cover plate structure provided by the present utility model has the following beneficial effects: The square battery cell exhaust cover plate structure solves the problem of the central housing bulging caused by gas production during the normal use of the battery cell through the gas storage chamber of the battery cell cover plate, and reduces the stress pressure of the structural parts; The dual design of the auxiliary exhaust valve and the explosion-proof valve discharges the gas produced by the battery cell in stages. Based on this, the opening pressure thresholds of the two can be further clearly distinguished to solve the failure problem caused by the low setting accuracy of the exhaust valve opening pressure in the original battery cell design; In the case of extreme internal gas production, multiple explosion-proof valves on the cover plate are opened simultaneously, which can reduce the risk of battery cell explosion; The gas storage chamber structure on the top of the cover plate is flush with structures such as the pole column and the explosion-proof valve in the longitudinal height, does not occupy too much effective internal space of the battery pack, and because of its integrated setting, it has no impact on the structural strength of the battery cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present utility model. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0028] Figure 1 It is an installation schematic diagram of the square battery cell exhaust cover plate structure of the present utility model.

[0029] Figure 2 It is a schematic diagram of the cover plate body structure of the square battery cell exhaust cover plate structure of the present utility model.

[0030] Figure 3 It is a cross-sectional schematic diagram of the cover plate body of the square battery cell exhaust cover plate structure of the present utility model.

[0031] Figure 4 It is a cross-sectional schematic diagram of the exhaust structure of the square battery cell exhaust cover plate structure of the present utility model.

[0032] In the figure: 1. Exhaust structure; 2. Explosion-proof valve; 3. Liquid injection hole; 4. Pole column; 101. Auxiliary exhaust valve; 102. Gas storage chamber; 103. Positioning and pressing structure; 104. Sealing plug. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts fall within the scope of protection of the present utility model.

[0034] Therefore, the detailed description of the embodiments of the present utility model provided in the accompanying drawings is not intended to limit the scope of the claimed present utility model, but merely represents selected embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without making creative efforts fall within the scope of protection of the present utility model.

[0035] It should be noted that like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not require further definition and explanation in subsequent drawings.

[0036] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present utility model.

[0037] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the number of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality of" means two or more unless otherwise specifically defined.

[0038] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be directly connected, or indirectly connected through an intermediate medium, and may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0039] In the present utility model, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over", and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath", and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0040] In order to enable those skilled in the art to better understand the technical solutions of the present utility model, the present utility model will be further described in detail below with reference to the accompanying drawings.

[0041] As Figures 1-4 shown, in one embodiment, a square battery cell exhaust cover plate structure of the present utility model includes

[0042] a cover plate body, which covers the square battery cell;

[0043] at least one exhaust structure 1, which is arranged on the cover plate body, and the exhaust structure 1 includes

[0044] a gas storage chamber 102, which is a cavity formed by the cover plate body protruding away from the square battery cell to accommodate gas,

[0045] a through hole, which is arranged at the bottom of the gas storage chamber 102 and communicates with the square battery cell,

[0046] a positioning and pressing structure 103, which is arranged on the top inner wall of the gas storage chamber 102 relative to the through hole, and the positioning and pressing structure 103 includes a spring block for pressing,

[0047] a sealing plug 104, which is fixedly connected to the spring block and presses and seals the through hole via the spring block;

[0048] at least one auxiliary exhaust valve 101, which is arranged on the top inner wall of the gas storage chamber 102 relative to the through hole and can switch the on-off between the gas storage chamber 102 and the external environment;

[0049] An explosion-proof valve 2 is provided on the cover body, and the second pressure threshold at which the explosion-proof valve 2 opens is greater than or equal to the first pressure threshold at which the auxiliary exhaust valve 101 opens.

[0050] In a preferred embodiment of the square battery cell exhaust cover structure, the first pressure threshold is greater than the pressure exerted by the spring block.

[0051] In a preferred embodiment of the square battery cell exhaust cover structure, the cover body further includes a terminal 4 and a liquid injection hole 3.

[0052] In a preferred embodiment of the square battery cell exhaust cover structure, the height of the raised air storage chamber 102 is flush with the height of the terminal 4.

[0053] In a preferred embodiment of the square battery cell exhaust cover structure, the explosion-proof valve 2 is located at the middle position of the high plate body, and at least two exhaust structures 1 are located on both sides of the explosion-proof valve 2.

[0054] In a preferred embodiment of the square battery cell exhaust cover structure, the positioning and pressing structure and the through hole are both provided on the central axis of the air storage chamber 102 and are arranged oppositely.

[0055] In a preferred embodiment of the square battery cell exhaust cover structure, the positioning and pressing structure further includes a side wall for positioning and guiding the spring block.

[0056] In a preferred embodiment of the square battery cell exhaust cover structure, the side wall extends vertically towards the through hole.

[0057] In a preferred embodiment of the square battery cell exhaust cover structure, the side wall is a cylindrical wall.

[0058] In a preferred embodiment of the square battery cell exhaust cover structure, the sealing plug 104 is a truncated cone structure.

[0059] In one embodiment, during the normal use of the battery cell, when the gas generated by continuous side reactions in the cell package area accumulates to a certain amount, the internal air pressure increases, and the pressure accumulates in the bottom area of the silicone sealing plug 104; when the pressure reaches the spring compression threshold, the sealing plug 104 is pushed up, and the internal gas escapes to the air storage chamber 102; subsequently, the air pressure in the cell package area decreases, and the sealing plug 104 reseals the through hole due to the spring pressure. The above process can be repeated multiple times during the use of the battery cell, and finally, the air storage chamber 102 is filled with the generated gas.

[0060] In the case of a large amount of gas generation inside the battery cell, the internal air pressure rises sharply. Since the first pressure threshold for opening the auxiliary exhaust valve 101 is set to be less than the second pressure threshold of the explosion-proof valve 2 and the gas storage chamber 102 is already filled with side reaction gases at this moment, the auxiliary exhaust valves 101, such as 4 at the top, will open first; if it is still not sufficient to control the internal air pressure, the explosion-proof valve 2 will finally open for pressure relief. In extreme cases, the auxiliary exhaust valve 101 and the explosion-proof valve 2 can also open simultaneously to further reduce the risk of battery cell explosion.

[0061] Finally, it should be noted that the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0062] Only some exemplary embodiments of the present invention have been described by way of illustration above. Undoubtedly, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of the claims of the present invention.

Claims

1. A square battery cell exhaust cover structure, characterized in that: These include, A cover plate body, which covers the square battery cell; At least one exhaust structure, which is arranged on the cover body, and the exhaust structure includes: The gas storage chamber is a cavity for accommodating gas formed by the cover body protruding away from the square battery core. A through hole is provided at the bottom of the gas storage bin and is connected to the square battery cell. A positioning and pressing structure is arranged on the top inner wall of the gas storage bin relative to the through hole, and the positioning and pressing structure includes a spring block for pressing. A sealing plug, which is fixedly connected to the spring block and is pressed and sealed by the spring block to seal the through hole; At least one auxiliary exhaust valve, which is arranged on the top inner wall of the gas storage bin relative to the through hole and can switch the connection between the gas storage bin and the external environment; An explosion-proof valve is arranged on the cover plate body and a second pressure threshold for opening the explosion-proof valve is greater than or equal to a first pressure threshold for opening the auxiliary exhaust valve.

2. A square battery core exhaust cover structure according to claim 1, characterized in that: The first pressure threshold is greater than the pressure applied by the spring block.

3. A square battery core exhaust cover structure according to claim 1, characterized in that: The cover plate body also includes a pole and a liquid injection hole.

4. A square battery core exhaust cover structure according to claim 3, characterized in that: The height of the protrusion of the gas storage bin is flush with the height of the pole.

5. A square battery core exhaust cover structure according to claim 1, characterized in that: The explosion-proof valve is located in the middle of the high plate body, and at least two exhaust structures are located on both sides of the explosion-proof valve.

6. A square battery core exhaust cover structure according to claim 1, characterized in that: The positioning and pressing structure and the through hole are both arranged on the central axis of the gas storage bin and are arranged relatively.

7. A square battery core exhaust cover structure according to claim 1, characterized in that: The positioning and pressing structure also includes a side wall for positioning and guiding the spring block.

8. A square battery core exhaust cover structure according to claim 7, characterized in that: The side wall extends vertically toward the through hole.

9. A square battery core exhaust cover structure according to claim 7, characterized in that: The side wall is a cylindrical wall.

10. A square battery core exhaust cover structure according to claim 1, characterized in that: The sealing plug is a truncated cone structure.

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