Patent Description:
Lithium-ion batteries have high requirements on the sealing of structures, and no electrolyte can seep out during use, otherwise the surrounding air and environment will be polluted, and no water vapor can enter the interior of the battery, since if water vapor reacts with the electrolyte, the service life of the battery assembly of a battery will be reduced.

The initial filling of the electrolyte of the battery is usually performed in the production stage, and after finishing the filling of electrolyte, the liquid injection hole needs to be sealed to ensure the sealing of the battery. If the battery needs to be refilled after use, the sealing structure of the liquid injection hole can be opened to finish refilling, and then the liquid injection hole is resealed after refilling.

At present, the battery liquid injection hole generally is sealed by a T-shaped sealing nail as a sealing element, and a columnar part of the sealing nail is inserted into the liquid injection hole, a nail head of the sealing nail is located outside the cover plate body, and then a metal cover is welded on the outside of the nail head to achieve resealing.

EP patent application published as <CIT> provides an end cover assembly, a battery cell, a battery pack, apparatus and a liquid injection method. The end cover assembly includes an end cover plate, including a through hole for injecting electrolyte and a fixing portion arranged around the through hole; a nail body, including an accommodating portion for receiving the fixing portion. The accommodating portion is in a shape of annular and includes two inner walls arranged to be spaced apart from each other in a radial direction of the accommodating portion, and an inner wall and an outer wall of the fixing portion are respectively pressed against and engaged with the two inner walls of the accommodating portion to seal the through hole. In the embodiments of the present application, the annular accommodating portion can provide the position limitations in two directions to the fixing portion, so that the force exerted to the fixing portion is balanced, not only can prevent the fixing portion from obliquely deforming, but also can increase the contact area between the nail body and the fixing portion to improve the sealing effect.

US patent application published as <CIT> discloses a battery module that includes a hermetically sealed battery cell assembly. The battery cell assembly includes a housing and an electrochemical cell disposed in the housing, wherein the housing includes a fill hole configured to receive electrolyte into the battery cell assembly. The battery cell assembly also includes a seal disposed over the fill hole and ultrasonically welded to an annular portion of the housing around the fill hole.

The purpose of the present disclosure is to provide a top cover assembly for a battery, a battery and a device using a battery as a power source.

A first aspect of the present disclosure provides a top cover assembly of a battery, including:.

In some embodiments, an anti-release part is arranged between the inner peripheral surface of the first side wall and the outer peripheral surface of the mounting part, and the anti-release part is configured to prevent the sealing element from separating from the mounting part.

In some embodiments, the anti-release part includes a bump or a rough area, the bump or the rough area is arranged on at least one of the inner peripheral surface of the first side wall and the outer peripheral surface of the mounting part.

In some embodiments, the top cover assembly further includes a first connecting part, and the first connecting part is configured to connect the first side wall and the mounting part.

In some embodiments, the first connecting part includes:.

In some embodiments, the first top wall is in press fit with the mounting part, to achieve sealed connection between the sealing element and the mounting part.

In some embodiments, the first top wall is provided with a sealing ring protruding towards the mounting part, and the sealing ring is configured to be in press fit with the mounting part.

In some embodiments, the outer peripheral surface of the mounting part is provided with a recessed part which is inwardly recessed, and the recessed part is configured to accommodate part of the first side wall.

In some embodiments, the cover plate body is provided with a groove, the groove is configured to accommodate at least part of the sealing element, and the mounting part is connected to the bottom wall of the groove.

According to the invention, the fixing element includes a second top wall and a second side wall connected to the outer periphery of the second top wall, wherein.

In some embodiments, a gap is formed between at least part of the first side wall and at least part of the second side wall.

In some embodiments, the top cover assembly further includes a second connecting part, the second connecting part is configured to connect the first side wall and the second side wall, and the second connecting part includes:.

A second aspect of the present disclosure provides a battery, including:.

A third aspect of the present disclosure provides a device using a battery as a power source, including the battery of the second aspect of the present disclosure, and the battery is used for providing electric energy.

Based on the top cover assembly provided in the embodiments of the present disclosure, a first top wall of the sealing element covers a liquid injection hole and the inner peripheral surface of a first side wall of the sealing element is in press fit with the outer peripheral surface of the mounting part, to achieve sealing of the liquid injection hole by the sealing element. Since no sealing part is arranged in the liquid injection hole and the mounting part, the internal space of the battery is increased. Since the internal space of the battery is relatively increased, the battery using the top cover assembly can have at least one of the following advantages: it is beneficial to increasing the energy density of the battery; more space can be formed to store gas generated when the battery is used, such that more gas can be accommodated inside the housing of the battery, which is beneficial to reducing the lithium precipitation phenomenon of the battery; it is beneficial to reducing the force subjected to the explosion-proof valve of the battery by the gas generated inside the housing, and it is beneficial to prolonging the service life of the explosion-proof valve.

Other features and advantages of the present disclosure will become clear through the following detailed description of exemplary embodiments of the present disclosure with reference to the accompanying drawings.

The drawings described herein are used to provide further understanding of the present disclosure and constitute a part of the present application. The exemplary embodiments of the present disclosure and their descriptions are used to explain the present disclosure, rather than constituting an improper limitation of the present disclosure. In the accompanying drawings:.

A clear and complete description will be given below on the technical solutions in the embodiments of the present disclosure in combination with accompanying drawings in the embodiments of the present disclosure, and apparently the embodiments described below are only a part but not all of the embodiments of the present disclosure. The description of at least one exemplary embodiment below is actually merely illustrative, rather than serving as any limitation to the present disclosure and its applications or uses.

Unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn in accordance with actual proportional relationships. The technologies, methods, and equipment known to those of ordinary skills in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be regarded as part of the authorization specification. In all the examples shown and discussed herein, any specific value should be interpreted as merely exemplary, rather than as a limitation. Therefore, other examples of the exemplary embodiment may have different values. It should be noted that similar reference numerals and letters indicate similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further discussed in the subsequent drawings.

In the description of the present disclosure, it should be understood that, the use of such words as "first" and "second" to define parts is merely to facilitate distinguishment of corresponding parts, unless otherwise stated, the above words have no special meanings, and should not be understood as a limitation to the protection scope of the present disclosure.

In the description of the present disclosure, it should be understood that, the orientation or positional relationship indicated by such terms as "front, rear, up, down, left, right", "lateral, longitudinal, vertical, horizontal", and "top, bottom" is generally based on orientation or positional relationship shown in the accompanying drawings. Such terms are merely for the convenience of description of the present disclosure and simplified description, rather than indicating or implying that the device or element referred to must be located in a certain orientation or must be constructed or operated in a certain orientation without a statement to the contrary, therefore, the terms cannot be understood as a limitation to the protection scope of the present disclosure; and such orientation terms as "inner, outside" mean inner or outside relative to the contour of each part itself.

In the process of finding the present application, the inventor found that in the aforementioned related technologies that use sealing nails to seal the liquid injection hole, since the columnar part of the sealing nail is inserted into a liquid injection hole, the columnar part extending into the liquid injection hole seals the liquid injection hole based on its own expansion. A guiding oblique angle on the columnar part is further required during assembly, the height occupied by the guiding oblique angle is an invalid sealing size and occupies the space in the height direction, moreover, the columnar part of the sealing nail extends into the liquid injection hole, resulting in that the space for producing gas inside the battery is small.

For this reason, embodiments of the present disclosure provide a top cover assembly for a battery, a battery and a device using a battery as a power source.

The device using a battery as a power source in the embodiments of the present disclosure includes a battery for providing electric energy. The device may be for example a vehicle, a ship, an energy storage device and the like.

As shown in <FIG> and <FIG>, the battery of the embodiments of the present disclosure mainly includes a top cover assembly <NUM>, a housing <NUM> and an electrode assembly <NUM>. The housing <NUM> is configured to be connected with the top cover assembly <NUM> and form an accommodating cavity. The electrode assembly <NUM> is arranged in the accommodating cavity.

As shown in <FIG> and <FIG>, the battery further includes an adapter sheet <NUM> and an insulating sheet <NUM>. The top cover assembly <NUM> includes a pole column <NUM>. The electrode assembly <NUM> is electrically connected to the pole column <NUM> of the top cover assembly <NUM> through the adapter sheet <NUM>. The insulating sheet <NUM> is arranged in the accommodating cavity of the battery and is located between the electrode assembly <NUM> and the housing <NUM> for insulating and protecting the electrode assembly <NUM>.

As shown in <FIG>, the top cover assembly <NUM> includes a cover plate body <NUM>, a liquid injection hole sealing structure, a pole column <NUM> and an explosion-proof valve <NUM>. The liquid injection hole sealing structure is configured to seal the liquid injection hole <NUM> on the sealing cover plate body <NUM>.

In some embodiments, the liquid injection hole sealing structure includes a mounting part <NUM> and a sealing element <NUM>; in some embodiments, the liquid injection hole sealing structure includes a mounting part <NUM>, a sealing element <NUM> and a fixing element <NUM>.

As shown in <FIG>, the top cover assembly <NUM> of the battery in the embodiment of the present disclosure mainly includes a cover plate body <NUM>, a mounting part <NUM> and a sealing element <NUM>.

The cover plate body <NUM> is provided with a liquid injection hole <NUM>. The mounting part <NUM> is configured to be connected with the cover plate body <NUM>, and is arranged to surround the liquid injection hole <NUM>. The sealing element <NUM> is configured to be connected with the mounting part <NUM>. The sealing element <NUM> includes a first top wall <NUM> and a first side wall <NUM> connected to the periphery of the first top wall <NUM>. The first top wall <NUM> is configured to cover the liquid injection hole <NUM>, and the first side wall <NUM> is configured to be in press fit with the mounting part <NUM>, to achieve sealing of the liquid injection hole <NUM>.

Based on the top cover assembly <NUM> provided in the embodiments of the present disclosure, a first top wall <NUM> of the sealing element <NUM> covers a liquid injection hole <NUM> and the inner peripheral surface of a first side wall <NUM> of the sealing element <NUM> is in press fit with the outer peripheral surface of the mounting part <NUM>, to achieve sealing of the liquid injection hole <NUM> by the sealing element <NUM>. Since no sealing part is arranged in the liquid injection hole <NUM> and the mounting part <NUM>, compared with the related technology in which a sealing nail is adopted to seal the liquid injection hole, the internal space of the battery is increased. Since the internal space of the battery is relatively increased, the battery using the top cover assembly <NUM> can have at least one of the following advantages: it is beneficial to increasing the energy density of the battery; more space can be formed to store gas generated when the battery is used, such that more gas can be accommodated inside the housing of the battery, which is beneficial to reducing the lithium precipitation phenomenon of the battery; it is beneficial to reducing the force subjected to the explosion-proof valve <NUM> of the battery by the gas generated inside the housing, and it is beneficial to prolonging the service life of the explosion-proof valve <NUM>.

In some embodiments, an anti-release part is arranged between the inner peripheral surface of the first side wall <NUM> and the outer peripheral surface of the mounting part <NUM>, and the anti-release part is configured to prevent the sealing element <NUM> from separating from the mounting part <NUM>.

In some embodiments the anti-release part includes a bump <NUM>, and the bump <NUM> is arranged in at least one of the inner peripheral surface of the first side wall <NUM> and the outer peripheral surface of the mounting part <NUM>.

In some other embodiments, the anti-release part may include a rouge area arranged on at least one of the inner peripheral surface of the first side wall <NUM> and the outer peripheral surface of the mounting part <NUM>.

The frictional force between the inner peripheral surface of the first side wall <NUM> and the outer peripheral surface of the mounting part <NUM> can be increased through the rough area or the bump <NUM> to increase the adhesion force between the sealing element <NUM> and the mounting part <NUM>, therefore it is beneficial to preventing the sealing element <NUM> from separating from the mounting part <NUM> and is beneficial to ensuring the sealing effect on the liquid injection hole <NUM>.

In some embodiments, the top cover assembly <NUM> further includes a first connecting part. The first connecting part is configured to connect the first side wall <NUM> and the mounting part <NUM>. The setting of the first connecting part can increase firmness of connection between the sealing element <NUM> and the mounting part <NUM>, which is beneficial to preventing the sealing element <NUM> from separating from the mounting part <NUM>, and further beneficial to ensuring sealing effect on the liquid injection hole <NUM>.

In some embodiments, the first connecting part includes a first connecting convex part and a first connecting concave part. The first connecting convex part is arranged in one of the first side wall <NUM> and the mounting part <NUM>. The first connecting convex part is arranged in the other of the first side wall <NUM> and the mounting part <NUM>. Wherein the first connecting convex part is configured to be connected with the first connecting concave part.

Wherein the shape of the first connecting convex part is preferably matched with the shape of the first connecting concave part.

For example, the first connecting convex part may be a first convex ring arranged on one of the first side wall <NUM> or the mounting part <NUM>, and the first connecting concave part may include a first convex ring which is shape-matched with the first convex ring and arranged on the other of the first side wall <NUM> or the mounting part <NUM>. Wherein the number of the first convex ring may be one or more, and the number of the first concave ring is the same as the number of the first convex ring.

For another example, the first connecting convex part may include a first protruding block arranged on one of the first side wall <NUM> or the mounting part <NUM>, and the second connecting concave part may include a first notch or a first opening which is shape-matched with the first protruding block and arranged on the other of the first side wall <NUM> or the mounting part <NUM>. Wherein the number of the first protruding block may be one or more, and the number of the first notch or the first opening is the same as the number of first protruding block.

In some embodiments, the first top wall <NUM> of the sealing element <NUM> is in press fit with the mounting part <NUM>, to achieve sealed connection between the sealing element <NUM> and the mounting part <NUM>.

Through press fit between the first side wall <NUM> of the sealing element <NUM> and the mounting part <NUM> and through press fit between the first top wall <NUM> of the sealing element <NUM> and the mounting part <NUM>, the sealing of the sealing element <NUM> on the liquid injection hole <NUM> is achieved, and further the sealing performance of the sealing element <NUM> on the liquid injection hole <NUM> is enhanced.

In some embodiments, the first top wall <NUM> of the sealing element <NUM> is provided with a sealing ring 12B protruding towards the mounting part <NUM>, and the sealing ring 12B is in press fit with the mounting part <NUM>.

The sealing ring 12B is more likely to achieve full circumferential contact with the mounting part <NUM> in the circumferential direction relative to the remaining parts of the first top wall <NUM>, thereby being beneficial to improving sealing performance between the first top wall <NUM> of the sealing element <NUM> and the mounting part <NUM>.

In some embodiments, the outer peripheral surface of the mounting part <NUM> is provided with a recessed part 14D which is inwardly recessed, and the recessed part 14D is configured to accommodate part of the first side wall <NUM> of the sealing element <NUM>. The setting is beneficial to firm fixation between the sealing element <NUM> and the mounting part <NUM>, is beneficial to preventing the sealing element <NUM> from being separated from the mounting part <NUM>, and is further beneficial to ensuring the sealing effect on the liquid injection hole <NUM>.

In some embodiments, the cover plate body <NUM> is provided with a groove, the groove is configured to accommodate at least part of the sealing element <NUM>, and the mounting part <NUM> is connected to the bottom wall of the groove.

A groove is arranged on the cover plate body <NUM>, and the mounting part <NUM> is arranged in the groove, which is beneficial to reducing the space above the top surface of the cover plate body <NUM> occupied by the mounting part <NUM> and the sealing element <NUM>, and is also beneficial to preventing external forces from affecting the firmness of connection between the sealing element <NUM> and the mounting part <NUM>, and is beneficial to preventing the sealing element <NUM> from being separated from the mounting part <NUM>, and is further beneficial to ensuring the sealing effect on the liquid injection hole <NUM>.

In some embodiments, the top cover assembly <NUM> further includes a fixing element <NUM>, the fixing element <NUM> is configured to be connected with the cover plate body <NUM> and fix the sealing element <NUM> to the mounting part <NUM>.

When the fixing element <NUM> is arranged, the firmness of the connection between the sealing element <NUM> and the mounting part <NUM> can be increased through the fixing element <NUM>, which is beneficial to preventing the sealing element <NUM> from being separated from the mounting part <NUM>, and is further beneficial to ensuring the sealing effect on the liquid injection hole <NUM>.

In some embodiments, the fixing element <NUM> includes a second top wall <NUM> and a second side wall <NUM> connected to the outer periphery of the second top wall <NUM>, wherein the second top wall <NUM> is in press fit with the first top wall <NUM> to fix the sealing element <NUM>; and/or, the second side wall <NUM> is in press fit with the first side wall <NUM> to fix the sealing element <NUM>.

The second top wall <NUM> of the fixing element <NUM> and the first top wall <NUM> of the sealing element <NUM> are in press fit and the second side wall <NUM> of the fixing element <NUM> and the first side wall <NUM> of the sealing element <NUM> are in press fit, which is beneficial to increasing the contact pressure between the sealing element <NUM> and the mounting part <NUM>, and further being beneficial to improving the sealing effect of the sealing element <NUM> on the liquid injection hole <NUM>.

In some embodiments, a gap G is formed between at least part of the first side wall <NUM> of the sealing element <NUM> and at least part of the second side wall <NUM> of the fixing element <NUM>. A gap G is formed between at least part of the first side wall <NUM> of the sealing element <NUM> and at least part of the second side wall <NUM> of the fixing element <NUM>, which is beneficial to the fixing element <NUM> to reach the assembly position smoothly during assembly, such that the second top wall <NUM> of the fixing element <NUM> can be effectively in press fit with the first top wall <NUM> of the sealing element <NUM>, thereby being beneficial to increasing the contact pressure between the first top wall <NUM> and the mounting part <NUM>, and is further beneficial to improving the sealing effect of the first top wall <NUM> of the sealing element <NUM> on the liquid injection hole <NUM>. In addition, it is beneficial to preventing the second side wall <NUM> of the fixing element <NUM> from scratching the first side wall <NUM> of the sealing element <NUM> during assembly.

In some embodiments, the top cover assembly <NUM> further includes a second connecting part. The second connecting part is configured to connect the first side wall <NUM> of the sealing element <NUM> and the second side wall <NUM> of the fixing element <NUM>.

The setting of the second connecting part is beneficial to firmer connection between the sealing element <NUM> and the fixing element <NUM>. After the fixing element <NUM> is connected with the cover plate body <NUM>, it is beneficial to firmer connection between the sealing element <NUM> and the mounting part <NUM>. Wherein the fixing element <NUM> can be directly connected with the cover plate body <NUM>, and can also be connected with the cover plate body <NUM> through the mounting part <NUM>.

In some embodiments, the second connecting part includes a second connecting convex part and a second connecting concave part. The second connecting convex part is arranged in one of the first side wall <NUM> and the second side wall <NUM>. The second connecting concave part is arranged in the other of the first side wall <NUM> and the second side wall <NUM>. The second connecting convex part is configured to be connected with the second connecting concave part.

In some embodiments, the shape of the second connecting convex part is matched with the shape of the second connecting concave part.

For example, the second connecting convex part may be a second convex ring arranged on one of the first side wall <NUM> or the second side wall <NUM>, and the second connecting concave part may include a second concave ring which is shape-matched with the second convex ring and arranged on the other of the first side wall <NUM> or the second side wall <NUM>. Wherein the number of the second convex ring may be one or more, and the number of the second concave ring is the same as the number of the second convex ring.

For another example, the second connecting convex part may include a second protruding block arranged on one of the first side wall <NUM> or the second side wall <NUM>, and the second connecting concave part may include a second notch or a second opening which is shape-matched with the second protruding block and arranged on the other of the first side wall <NUM> or the second side wall <NUM>. Wherein the number of second protruding block may be one or more, and the number of the second notch or the second opening is the same as the number of second protruding block.

The battery of the embodiment of the present disclosure includes the aforementioned top cover assembly <NUM>, therefore, the battery has corresponding advantages of the aforementioned top cover assembly <NUM>.

A more detailed description will be given below on the top cover assembly <NUM> for a battery of the embodiment of the present disclosure in combination with <FIG>.

As shown in <FIG>, the top cover assembly <NUM> includes a cover plate body <NUM>, a liquid injection hole sealing structure, a pole column <NUM> and an explosion-proof valve <NUM>.

The cover plate body <NUM> is provided with a liquid injection hole <NUM>. The liquid injection hole sealing structure is arranged on the cover plate body <NUM>, and is configured to seal the liquid injection hole <NUM>. As shown in <FIG>, the liquid injection hole sealing structure includes a mounting part <NUM> and a sealing element <NUM>.

The mounting part <NUM> is arranged around the liquid injection hole <NUM> to form a hollow column with an axial through hole. The axial through hole of the mounting part <NUM> is coaxial and communicated with the liquid injection hole <NUM>. The mounting part <NUM> is arranged on the cover plate body <NUM>, and the connection between the mounting part <NUM> and the cover plate body <NUM> is a sealed connection to prevent the liquid injection hole <NUM> from leaking from the connecting portion.

As shown in <FIG>, the sealing element <NUM> is connected to the mounting part <NUM>. The sealing element <NUM> is shaped like a sealing cap in the present embodiment, and is covered on the mounting part <NUM>. The sealing element <NUM> includes a first top wall <NUM> and a first side wall <NUM> extending from the outer periphery of the first top wall <NUM>. The first top wall <NUM> is covered above the axial through hole of the mounting part <NUM> to cover the liquid injection hole <NUM>. As shown in <FIG>, the inner peripheral surface of the first side wall <NUM> is in press fit with the outer peripheral surface of the mounting part <NUM>, to achieve sealing on the liquid injection hole <NUM>.

As shown in <FIG>, the mounting part <NUM> is shaped like a straight cylinder, and an anti-release part is arranged on the outer peripheral surface of the mounting part <NUM>. The anti-release part includes a plurality of bumps <NUM>. The plurality of bumps <NUM> are evenly distributed around the outer peripheral surface of the mounting part <NUM>. The plurality of bumps <NUM> are beneficial to preventing the sealing element <NUM> from separating from the mounting part <NUM> and are beneficial to ensuring the sealing effect on the liquid injection hole <NUM>.

As shown in <FIG>, the lower surface of the first top wall <NUM> is also in press fit with the top surface of the mounting part <NUM>, to enhance the sealing ability of the sealing element <NUM> on the liquid injection hole <NUM>.

In some embodiments, the mounting part <NUM> may be integrally formed with the cover plate body <NUM>. In the present embodiment, the cover plate body <NUM>, the mounting part <NUM> and the liquid injection hole <NUM> are formed by stamping with a mould, and the lower part of the liquid injection hole <NUM> of the cover plate body <NUM> is set in the form of a counterbore, to facilitate the formation of the mounting part <NUM> through extrusion. The mounting part <NUM> protrudes upwards and is higher than the top surface of the cover plate body <NUM>.

In some other embodiments, the mounting part <NUM> may also be assembled and connected to the cover plate body <NUM> after they are separately manufactured, for example, the mounting part <NUM> may be assembled and connected to the cover plate body <NUM> by means of welding, screwing, clamping, etc..

In the present embodiment, the sealing element <NUM> is made of an elastic material. In some embodiments, the sealing element <NUM> may be manufactured of fluororubber or ethylenepropylene rubber that are resistant to electrolyte. The use of an elastic material to manufacture the sealing element <NUM> is beneficial to a close fit between the sealing element <NUM> and the mating surface of the mounting part <NUM>, and is further beneficial to improving the sealing performance of the sealing element <NUM> on the liquid injection hole <NUM>.

The diameter of the inner peripheral surface of the first side wall <NUM> of the sealing element <NUM> is smaller than the diameter of the outer peripheral surface of the first mounting surface 14A of the mounting part <NUM> in a natural state. After the sealing element <NUM> and the mounting part <NUM> are assembled, the inner peripheral surface of the first side wall <NUM> of the sealing element <NUM> can be pressed against the outer peripheral surface of the mounting part <NUM>. After the sealing element <NUM> and the mounting part <NUM> are assembled, the bottom surface of the first top wall <NUM> is in press fit with the top surface of the mounting part <NUM>.

In the present embodiment, a sealing interface is formed between the first top wall <NUM> and the top surface of the mounting part <NUM>, a sealing interface is formed between the first side wall <NUM> and the outer peripheral surface of the mounting part <NUM>, therefore, the sealing effect on the liquid injection hole <NUM> is favorable.

<FIG> show an alternative embodiment of a top cover assembly <NUM> of the embodiment shown in <FIG>.

As shown in <FIG>, the liquid injection hole sealing structure includes a mounting part <NUM>, a sealing element <NUM> and a fixing element <NUM>. The outer peripheral surface of the mounting part <NUM> is a step surface. The sealing element <NUM> is shaped like a sealing cap, and includes a first top wall <NUM> and a first side wall <NUM> extending along the periphery of the first top wall <NUM>. The fixing element <NUM> is shaped like a cap in the present embodiment, and includes a second top wall <NUM> and a second side wall <NUM> extending along the periphery of the second top wall <NUM>. The fixing element <NUM> covers the outer side of the sealing element <NUM>, and is configured to fix the sealing element <NUM> on the mounting part <NUM> through fixed connection with the cover plate body <NUM>. In the embodiment shown in <FIG>, the fixing element <NUM> achieves fixed connection with the cover plate body <NUM> through fixed connection with the mounting part <NUM>.

As shown in <FIG>, the second top wall <NUM> of the fixing element <NUM> is in press fit with the first top wall <NUM> of the sealing element <NUM>, such that the first top wall <NUM> is reliably pressed against the mounting part <NUM>.

As shown in <FIG>, a gap G exists between the second side wall <NUM> of the fixing element <NUM> and the first side wall <NUM> of the sealing element <NUM>. The gap G is beneficial to the mounting of the fixing element <NUM> in place, which is beneficial to achieving press fit between the second top wall <NUM> of the fixing element <NUM> and the first top wall <NUM> of the sealing element <NUM>. The gap G is also beneficial to avoiding affecting the sealing performance or service life of the sealing element <NUM> due to the fixing element <NUM> scratching the first side wall <NUM> of the sealing element <NUM> during the assembly process.

As shown in <FIG>, the outer peripheral surface of the mounting part <NUM> includes a first mounting surface 14A and a second mounting surface 14B arranged below the first mounting surface 14A. The diameter of the second mounting surface 14B is greater than the diameter of the first mounting surface 14A. The inner peripheral surface of the first side wall <NUM> of the sealing element <NUM> is in press fit with the first mounting surface 14A. The second side wall <NUM> of the fixing element <NUM> is fixedly connected with the second mounting surface 14B.

In the present embodiment, the cover plate body <NUM>, the mounting part <NUM>, and the liquid injection hole <NUM> are formed by stamping with a mould. The outer peripheral surface of the mounting part <NUM> forms a step surface, wherein the radius difference between the second mounting surface 14B and the first mounting surface 14A is greater than the thickness of the first side wall <NUM> of the sealing element <NUM> to form a gap G.

The diameter of the inner peripheral surface of the first side wall <NUM> of the sealing element <NUM> is smaller than the diameter of the outer peripheral surface of the first mounting surface 14A of the mounting part <NUM> in a natural state. After the sealing element <NUM> is assembled with the mounting part <NUM>, the inner peripheral surface of the first side wall <NUM> of the sealing element <NUM> can be pressed against the outer peripheral surface of the mounting part <NUM>.

The fixing element <NUM> and the mounting part <NUM> can be fixedly connected by interference fit. At this time, the second side wall <NUM> of the fixing element <NUM> is pressed to make an interference fit between the inner peripheral surface of the second side wall <NUM> and the second mounting surface 14B of the mounting part <NUM>, so that the fixing element <NUM> and the mounting part <NUM> are fixedly connected.

The fixing element <NUM> may be made of a metal material, for example, the fixing element <NUM> may be made of a metal material with high strength and good ductility, such as aluminum. The wall thickness of the fixing element <NUM> can be selected according to the requirements of the structure and material of the fixing element <NUM>, and the connection method with the cover plate body <NUM>. For example, the fixing element <NUM> of the present embodiment is made of aluminum material, and the wall thickness can be <NUM> to <NUM>.

In some embodiments, the fixed connection between the fixing element <NUM> and the mounting part <NUM> may be achieved through threaded connection. At this time, the inner peripheral surface of the second side wall <NUM> is provided with a female thread, and the second mounting surface 14B of the mounting part <NUM> is provided with a male thread matching the female thread. During assembly, the fixing element <NUM> is screwed on the second mounting surface 14B of the mounting part <NUM>, to achieve fixed connection between the fixing element <NUM> and the mounting part <NUM>.

In some embodiments, such manners like clamping can be adopted to achieve fixed connection between the fixing element <NUM> and the mounting part <NUM>.

During the production process, when the battery with the top cover assembly <NUM> of the present embodiment is first filled, the electrolyte is filled into the accommodating cavity of the battery through the liquid injection hole <NUM>. After the electrolyte is filled, the sealing element <NUM> and the fixing element <NUM> are sequentially sleeved on the mounting part <NUM>.

The diameter of the inner peripheral surface of the first side wall <NUM> of the sealing element <NUM> is smaller than the diameter of the first mounting surface 14A of the mounting part <NUM>. The first side wall <NUM> is stretched when the sealing element <NUM> and the mounting part <NUM> are assembled. After assembly, the inner peripheral surface of the first side wall <NUM> forms pressure on the first mounting surface 14A to achieve sealing between the first side wall <NUM> of the sealing element <NUM> and the mounting part <NUM>.

After the sealing element <NUM> is assembled with the mounting part <NUM>, the bottom surface of the first top wall <NUM> is in press fit with the top surface of the mounting part <NUM>. After the fixing element <NUM> is assembled with the mounting part <NUM> and the sealing element <NUM>, a pressure is applied to an upper surface of the first top wall <NUM> of the sealing element <NUM>, the first top wall <NUM> of the sealing element <NUM> is pressed towards the top surface of the mounting part <NUM>, to achieve sealing between the first top wall <NUM> and the mounting part <NUM>.

In the present embodiment, a sealing interface is formed between the first top wall <NUM> and the top surface of the mounting part <NUM>, and a sealing interface is formed between the first side wall <NUM> and the outer peripheral surface of the mounting part <NUM>, therefore, the sealing effect on the liquid injection hole <NUM> is favorable.

When the battery is refilled, a tool is used to clamp and remove the fixing element <NUM>, and then the sealing element <NUM> is removed to expose the liquid injection hole <NUM> to refill the battery. After the refilling is completed, the new sealing element <NUM> and the fixing element <NUM> are assembled to the mounting part <NUM> to realize resealing of the liquid injection hole <NUM>, and the battery can be restored to use.

In the present embodiment, the mounting part <NUM> protrudes upwards relative to the top surface of the cover plate body <NUM>, such that the sealing interface between the sealing element <NUM> and the mounting part <NUM> is higher than the top surface of the cover plate body <NUM>. The deformation of the cover plate body <NUM> has a small influence on the mounting part <NUM>, which is beneficial to reducing the influence of the deformation of the cover plate body <NUM> on the sealing effect.

In the embodiments of the present disclosure, the liquid injection hole sealing structure of the top cover assembly <NUM> is simple, easy to manufacture, and has a small structural size. The connection of components of the liquid injection hole sealing structure is simple, and the disassembly and assembly of components are convenient, and repeated opening and closing of the liquid injection hole <NUM> can be realized, which is beneficial to realizing refilling when the battery is used, and the stability of the sealing performance of the liquid injection hole <NUM> before and after refilling can be realized, and the appearance of the battery before and after refilling can be maintained.

For the parts not illustrated in the embodiment shown in <FIG>, please refer to the related contents of the aforementioned embodiments.

<FIG> shows an alternative embodiment of the top cover assembly <NUM> in the embodiments shown in <FIG>. As shown in <FIG>, the embodiment differs from the embodiments shown in <FIG> in that the top cover assembly <NUM> further includes a second connecting part. Wherein the second connecting part includes a second connecting convex part and a second connecting concave part which are mutually matched.

As shown in <FIG>, in the present embodiment, the second connecting convex part includes a second convex ring 12A. The second convex ring 12A is arranged on the outer peripheral surface of the first side wall <NUM> of the sealing element <NUM>. The second connecting concave part includes a second concave ring that is shape-matched with the second convex ring 12A, and the second concave ring is arranged on the inner peripheral surface of the second side wall <NUM> of the fixing element <NUM>.

After the fixing element <NUM> is connected with the cover plate body <NUM> through a mounting part <NUM>, the second convex ring 12A is shape-matched with the first concave ring, which is beneficial to firmer connection between the sealing element <NUM> and the mounting part <NUM>.

<FIG> shows another alternative embodiment of a top cover assembly <NUM> in the embodiments shown in <FIG>.

As shown in <FIG>, the embodiment differs from the embodiments shown in <FIG> in that the first top wall <NUM> is provided with a sealing ring 12B protruding towards the mounting part <NUM>, and the sealing ring 12B is used for press fit with the mounting part <NUM>.

The sealing ring 12B is more likely to realize full circumferential contact with the mounting part <NUM> in the circumferential direction compared with the remaining parts of the first top wall <NUM>, thereby being beneficial to improving sealing performance between the first top wall <NUM> and the mounting part <NUM>.

In the present embodiment, the cross section of the sealing ring 12B is semi-circular, and in the embodiments not shown in the figures, the cross section of the sealing ring may also be rectangular, trapezoidal, triangular, and may be in other shapes.

In the present embodiment, the first top wall <NUM> is provided with a sealing ring 12B. In an embodiment not shown in the figure, the number of the sealing rings may be two or more.

As shown in <FIG>, another difference between the present embodiment and the embodiments shown in <FIG> lies in that the top cover assembly <NUM> includes a first connecting part, and the first connecting part includes a first connecting convex part and a first connecting concave part. The first connecting convex part is a first convex ring 12C arranged on the first side wall <NUM> of the sealing element <NUM>, and the first connecting concave part includes a first concave ring that is shape-matched with the first convex ring 12C and arranged on the mounting part <NUM>.

<FIG> shows an alternative embodiment of the top cover assembly <NUM> of the embodiments shown in <FIG>. As shown in <FIG>, the present embodiment differs from the embodiments shown in <FIG> in that the outer peripheral surface of the mounting part <NUM> is provided with a recessed part 14D which is inwardly recessed, and the recessed part 14D is configured to accommodate part of the first side wall <NUM> of the sealing element <NUM>. The setting is beneficial to firm fixation between the sealing element <NUM> and the mounting part <NUM>, is beneficial to preventing the sealing element <NUM> from being separated from the mounting part <NUM>, and is further beneficial to ensuring the sealing effect on the liquid injection hole <NUM>.

As shown in <FIG>, in the present embodiment, the upper part of the mounting part <NUM> is formed with an annular flange 14C protruding outwards in the radial direction relative to the lower part, and the aforementioned recessed part 14D which is inwardly recessed is formed between the bottom surface of the annular flange 14C and the top surface of the cover plate body <NUM>, and the recessed part 14D is annular.

In the present embodiment, the first side wall <NUM> of the sealing element <NUM> and the second side wall <NUM> of the fixing element <NUM> are both cylindrical before assembly. During assembly, the sealing element <NUM> is first sleeved on the top of the mounting part <NUM>, and then the fixing element <NUM> is sleeved on the outside of the sealing element <NUM>, and then the bottom of the second side wall <NUM> of the fixing element <NUM> is pressed towards the recessed part 14D, the second side wall <NUM> is permanently deformed to press the first side wall <NUM> of the sealing element <NUM> against the wall surface of the recessed part 14D, thereby fixing both the sealing element <NUM> and the fixing element <NUM> to the mounting part <NUM>.

In the process of producing the battery with the top cover assembly <NUM> of the present embodiment, during the initial filling, the electrolyte is filled into the accommodating cavity of the battery through the liquid injection hole <NUM>. After the electrolyte is filled, the sealing element <NUM> and the fixing element <NUM> are sequentially sleeved on the mounting part <NUM>, and a closing device is used to exert an acting force on the outer peripheral surface of the lower part of the second side wall <NUM> of the fixing element <NUM>, so that the fixing element <NUM> is gradually contracted. The lower part of the second side wall <NUM> of the fixing element <NUM> compresses the lower part of the first side wall <NUM> of the sealing element <NUM>, so that the lower part of the first side wall <NUM> is abutted and pressed against the recessed part 14D of the mounting part <NUM>. During the inward contraction process of the lower part of the second side wall <NUM> of the fixing element <NUM>, the fixing element <NUM> translates and deforms downwards as a whole, and the space between the top surface of the mounting part <NUM> and the second top wall <NUM> of the fixing element <NUM> is reduced, the second top wall <NUM> of the fixing element <NUM> compresses the first top wall <NUM> of the sealing element <NUM>, thereby enhancing the sealing performance of the second sealing interface between the first top wall <NUM> of the sealing element <NUM> and the fixing element <NUM>. As shown in <FIG>, after the assembly is completed, the bottom of the second side wall <NUM> of the fixing element <NUM> forms an inwardly recessed part 13C.

When the battery is refilled, a tool is used to remove the fixing element <NUM>, and the mounting part <NUM> is protected from deformation, and the sealing element <NUM> is removed to expose the liquid injection hole <NUM> to refill the battery. After the refilling is completed, the new sealing element <NUM> and the fixing element <NUM> are assembled to reseal the liquid injection hole <NUM>, and the battery can be restored to use.

In the present embodiment, the structure of the recessed part 14D and the connection manner between the fixing element and the mounting part <NUM> is beneficial to ensuring that the sealing element <NUM> and the fixing element <NUM> do not separate from the mounting part <NUM> due to vibration, shock and the like of the electrode assembly, thereby being beneficial to ensuring the sealing performance on the liquid injection hole <NUM>.

In some embodiments, the sealing element <NUM> and the fixing element <NUM> may not appear as a single body, but form a combined element. For example, the sealing element <NUM> is attached to the inside of the fixing element <NUM> in the form of a coating, such that the sealing element <NUM> and the fixing element <NUM> form a combined element. The thickness of the coating may be for example <NUM> to <NUM>. When the liquid injection hole <NUM> is sealed, the combined element is assembled on the mounting part <NUM>, and then the combined element is closed and sealed. The fitting degree of the sealing element <NUM> and the fixing element <NUM> in the combined element is higher, which is beneficial to alleviating the problem of decrease of the connection firmness caused by the air gap that may exist between the sealing element <NUM> and the fixing element <NUM> during the assembly process. At the same time, forming the sealing element <NUM> and the fixing element <NUM> into a combined element can reduce the number of parts and make the assembly simpler and more reliable.

In the embodiments not shown in the figures, the recessed part can also include a plurality of notches.

<FIG> show an alternative embodiment of the top cover assembly <NUM> of the embodiments shown in <FIG>. As shown in <FIG>, the present embodiment mainly differs from the embodiments shown in <FIG> in that the cover plate body <NUM> is provided with a groove, the groove is configured to accommodate at least part of the sealing element <NUM>, and the mounting part <NUM> is connected to the bottom wall of the groove.

The setting of a groove on the cover plate body <NUM> is beneficial to reducing the space above the top surface of the cover plate body <NUM> occupied upwards by the mounting part <NUM> and the sealing element <NUM>, and is also beneficial to preventing an external force from influencing connection firmness between the sealing element <NUM> and the mounting part <NUM>, thereby being beneficial to preventing the sealing element <NUM> from separating from the mounting part <NUM>, and further being beneficial to ensuring sealing effect on the liquid injection hole <NUM>.

As shown in <FIG>, in the present embodiment, the mounting part <NUM> is arranged in the groove of the cover plate body <NUM>. The outer peripheral surface of the mounting part <NUM> and the side wall of the groove of the cover plate body <NUM> form an annular cavity 11A, the first side wall <NUM> of the sealing element <NUM> and the second side wall <NUM> of the fixing element <NUM> are arranged in the annular cavity 11A. Wherein the second side wall <NUM> of the fixing element <NUM> is fixedly connected to the side wall of the groove of the cover plate body <NUM>.

As shown in <FIG>, in the present embodiment, the outer peripheral surface of the second side wall <NUM> of the fixing element <NUM> is provided with a male thread, and the side wall of the groove of the cover plate body <NUM> has a female thread that cooperates with the male thread. When the fixing element <NUM> and the cover plate body <NUM> are assembled, the fixing element <NUM> needs to be screwed into the groove of the cover plate body <NUM>.

As shown in <FIG>, in order to screw the fixing element <NUM>, the fixing element <NUM> is further provided with a clamping part for cooperating with a screwing tool. In the present embodiment, the clamping part includes a plurality of notches 13D arranged at the connecting portion between the second top wall <NUM> and the second side wall <NUM>.

In some embodiments not shown in the figures, the fixed connection between the fixing element <NUM> and the cover main body <NUM> can be realized through interference fit between the second side wall <NUM> of the fixing element <NUM> and the side wall of the groove of the cover plate body <NUM>. At this time, the aforementioned clamping part of the fixing element <NUM> is not necessary.

For the part not illustrated in the embodiments shown in <FIG>, please refer to related contents of the aforementioned embodiments.

Claim 1:
A top cover assembly for a battery, comprising:
a cover plate body (<NUM>) having a liquid injection hole (<NUM>);
a mounting part (<NUM>) configured to be connected with the cover plate body (<NUM>) and arranged around the liquid injection hole (<NUM>);
a sealing element (<NUM>) configured to be connected with the mounting part (<NUM>) and comprising a first top wall (<NUM>) and a first side wall (<NUM>) connected to the periphery of the first top wall (<NUM>), wherein the first top wall (<NUM>) is configured to cover the liquid injection hole (<NUM>), and the first side wall (<NUM>) is configured to be in press fit with the mounting part (<NUM>) to achieve sealing of the liquid injection hole (<NUM>); and
a fixing element (<NUM>) configured to be connected with the cover plate body (<NUM>) and fix the sealing element (<NUM>) to the mounting part (<NUM>);
characterised in that:
the fixing element (<NUM>) comprises a second top wall (<NUM>) and a second side wall (<NUM>) connected to the outer periphery of the second top wall (<NUM>);
wherein the second top wall (<NUM>) is in press fit with the first top wall (<NUM>) to fix the sealing element (<NUM>); and/or
the second side wall (<NUM>) is in press fit with the first side wall (<NUM>) to fix the sealing element (<NUM>).