CN217740662U - End cover assembly, battery monomer, battery and power consumption device - Google Patents

Abstract

The application provides an end cover assembly, a single battery, a battery and an electric device, wherein the end cover assembly comprises an end cover and a pole, the end cover is provided with a first face and a second face which are opposite, the first face faces back to the interior of the single battery, and the end cover is provided with a through hole which penetrates through the first face and the second face; the bottom surface of the pole is hermetically connected with the first surface through a sealing element, and the pole covers the through hole; wherein the seal is in a compressed state, and a compression rate of the seal in an initial compressed state is configured to be 10% or more and 50% or less. By the design, the sealing element has good sealing performance in the whole life cycle of the battery, so that the risk of sealing failure of the battery is reduced, and the safety performance of the battery is improved.

Description

End cover assembly, battery monomer, battery and power consumption device

Technical Field

The application relates to the technical field of batteries, in particular to an end cover assembly, a battery monomer, a battery and an electric device.

Background

Energy conservation and emission reduction are the key points of sustainable development of the automobile industry, and electric vehicles become important components of the sustainable development of the automobile industry due to the advantages of energy conservation and environmental protection. For electric vehicles, battery technology is an important factor in its development.

At present, the pole of the battery is connected to the end cap of the battery through a sealing element in a sealing manner, and the sealing element realizes sealing. However, if the sealing performance of the sealing member is weakened during the entire life cycle of the battery, the electrode post is likely to be deformed by creep deformation, which causes the sealing failure of the battery, thereby causing leakage of the electrolyte solution and affecting the safety of the battery.

SUMMERY OF THE UTILITY MODEL

The present application is directed to solving at least one of the problems in the prior art. To this end, it is an object of the present application to provide an end cap assembly, a battery cell, a battery, and a power device that reduce the likelihood that the performance of the seal will degrade over the life cycle of the battery, resulting in a failure of the seal of the battery.

An embodiment of a first aspect of the present application provides an end cap assembly, which includes an end cap and a terminal post, wherein the end cap has a first surface and a second surface opposite to each other, the first surface faces away from the interior of a battery cell, and the end cap is provided with a through hole penetrating through the first surface and the second surface; the bottom surface of the pole is hermetically connected with the first surface through a sealing element, and the pole covers the through hole; wherein the seal is in a compressed state, and a compression rate of the seal in an initial compressed state is configured to be 10% or more and 50% or less.

In the technical scheme of this application embodiment, the compressibility of sealing member when the battery full life cycle's earlier stage is not less than 10%, and the compressibility of sealing member can not the undersize, and then the sealing performance of sealing member is good for the battery keeps sealed. Moreover, because the compression ratio of the sealing member in the initial compression state does not exceed 50%, even if the deformation amount of the sealing member is increased and the compression ratio is increased along with the increase of the service life of the battery, the compression ratio of the sealing member is not increased to be too large to cause the stress relaxation of the sealing member in the later period of the full life cycle of the battery, so that the sealing member still can have certain resilience in the later period of the full life cycle of the battery, and the sealing performance of the sealing member cannot be lost, so that the battery can keep sealed.

In some embodiments, the compression ratio of the seal in the initial compressed state is configured to be 15% or more and 50% or less. The lower limit value of the compression ratio of the sealing element in the initial compression state is improved, and the compression ratio of the sealing element is further ensured not to be too small in the early stage of the full life cycle of the battery, so that the sealing element can sufficiently seal the through hole, and the electrolyte leakage of the battery is avoided.

In some embodiments, the end cover is concavely formed with a mounting groove, and the groove bottom surface of the mounting groove is a first surface. Like this, reduced the space that utmost point post took in the free direction of height of battery, under the prerequisite that does not change the free overall height of battery, can effectively increase the free inside space of battery, then the quantity increase of the pole piece that the inside can of this battery is inside, and then has promoted the free active material capacity of battery to can promote the free energy density of battery.

In some embodiments, the second surface is a bottom surface of the end cap, and a distance between the first surface and the second surface is a first distance along a thickness direction of the end cap, and the first distance is greater than or equal to 1mm, so that the position on the end cap where the mounting groove is formed is ensured to have certain strength, the end cap has high structural strength, and the safety performance of the battery is ensured.

In some embodiments, a region of the second face of the end cap corresponding to the mounting groove is convexly provided with a boss toward the inside of the battery cell. So, the thickness of the groove diapire of increase mounting groove, and then be favorable to guaranteeing to set up the position of mounting groove on the end cover and still have certain intensity for the end cover has higher structural strength, and the security performance of battery can be guaranteed.

In some embodiments, the pole post further comprises a fixing piece, the fixing piece surrounds the outer side of the pole post and the sealing piece, and the fixing piece is connected with the first face. Through setting up the mounting, utmost point post can be fixed in the end cover through the mounting connection, and then is favorable to improving the installation stability of utmost point post.

In some embodiments, the mounting groove includes a first sub-groove and a second sub-groove, a sectional area of the first sub-groove is larger than a sectional area of the second sub-groove, and a groove bottom surface of the second sub-groove is the first surface; the groove bottom surface of the first subslot and the groove side surface of the second subslot form a step together, and the fixing piece is abutted to the step side wall of the step. From this, the mounting is not only connected with first face, still is connected with the groove side of second subslot, and the joint strength of mounting and end cover improves, and then further improves the stability of being connected of utmost point post and end cover.

In some embodiments, the bottom surface of the fixing member is recessed to form a groove, and the groove wall of the groove and the outer peripheral surface of the sealing member in the original state jointly define an avoidance space, wherein the avoidance space is configured to accommodate the deformation amount of the sealing member from the original state to the initial compressed state. By the design, in the assembling process of the end cover assembly, the sealing element is extruded by the pole and is changed into an initial compression state from an original state, and the compressed compression amount of the sealing element can be accommodated in an avoiding space formed by the groove of the fixing element and the peripheral surface of the sealing element in an enclosing mode so as to prevent the fixing element from interfering with the deformed sealing element.

In some embodiments, the sealing element is a circular ring-shaped sealing ring, the cross section of the groove is circular, and the deformation amount and the avoidance space of the sealing ring compressed from the original state to the initial compression state satisfy:

；

wherein, R1 is the inner diameter of the sealing ring in the original state, R2 is the outer diameter of the sealing ring in the original state, R3 is the inner diameter of the groove, H1 is the thickness of the sealing ring in the original state, H2 is the thickness of the sealing ring in the initial compression state, and H5 is the depth of the groove.

In some embodiments, an annular boss is convexly arranged on the first surface and surrounds the through hole; the sealing member includes first sealing and the second sealing that links to each other, and first sealing butt is between the bottom surface and the first face of utmost point post, and second sealing butt is between the bottom surface and the annular boss of utmost point post. The periphery side of annular boss is located to the sealing member cover, then annular boss can play certain limiting displacement to the sealing member to the play phenomenon appears in the radial direction of restriction sealing member along the through-hole, is favorable to improving the sealed effect of sealing member to the through-hole.

In some embodiments, the seal further comprises an annular seal portion connected to the second seal portion, and the annular seal portion is mounted within the through bore. When the parts of the pole lug and the pole of the conducting core assembly stretch into the through hole and are connected with the pole, the annular sealing part can separate the adapter from the end cover, and therefore the electric energy transmitted by the pole assembly to the pole is guided to the end cover, and the safety of the battery is guaranteed.

Embodiments of a second aspect of the present application provide a battery cell including the end cap assembly of the above embodiments.

Embodiments of the third aspect of the present application provide a battery including a battery cell provided by embodiments of the second aspect of the present application.

Embodiments of the fourth aspect of the present application provide an electric device including a battery provided by embodiments of the third aspect of the present application.

The foregoing description is only an overview of the technical solutions of the present application, and the present application can be implemented according to the content of the description in order to make the technical means of the present application more clearly understood, and the following detailed description of the present application is given in order to make the above and other objects, features, and advantages of the present application more clearly understandable.

Drawings

In the drawings, like reference characters designate like or similar parts or elements throughout the several views unless otherwise specified. The figures are not necessarily to scale. It is appreciated that these drawings depict only some embodiments in accordance with the disclosure and are therefore not to be considered limiting of its scope.

FIG. 1 is a schematic structural view of a vehicle according to some embodiments of the present application;

fig. 2 is an exploded view of a battery according to some embodiments of the present application;

fig. 3 is an exploded view of a battery cell according to some embodiments of the present disclosure;

FIG. 4 is a schematic cross-sectional view of an end cap assembly of some embodiments of the present application with the pole uninstalled and the seal in an original state;

FIG. 5 is a cross-sectional schematic view of an end cap assembly according to some embodiments of the present application;

FIG. 6 is a top view of an end cap according to other embodiments of the present application;

FIG. 7 isbase:Sub>A schematic cross-sectional view A-A of the end cap of FIG. 6;

FIG. 8 is an enlarged view of a portion of FIG. 7 at B;

FIG. 9 is a top view of an end cap assembly of other embodiments of the present application having the end cap shown in FIG. 6;

FIG. 10 is a schematic cross-sectional view of the end cap assembly shown in FIG. 9 taken along the direction C-C;

FIG. 11 is an enlarged view of a portion of FIG. 10 at D;

FIG. 12 is a partial cross-sectional schematic view of an endcap assembly according to still other embodiments of the present application.

Description of reference numerals:

1000-a vehicle;

100-a battery;

10-a box body; 11-a first part; 12-a second part;

20-a battery cell; 21-an end cap assembly; 210-an end cap; 2101-first side; 2102-annular boss; 2103-a second side; 2104-boss; 2105-through holes; 2106-air release holes; 2107-mounting grooves; 2107 a-first subslot; 2107 b-a second subslot; 211-pole column; 212-a seal; 2121-first sealing part; 2122-a second seal; 2123-annular seal; 213-a pressure relief member; 214-a fixing member; 2141-a first fastener; 2142-a second fixing member; 2143-a groove; 215-a seal;

22-a housing; 23-an electric core assembly; 23 a-a tab;

200-a controller;

300-motor.

Detailed Description

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The following examples are only used to illustrate the technical solutions of the present application more clearly, and therefore are only used as examples, and the protection scope of the present application is not limited thereby.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "including" and "having," and any variations thereof, in the description and claims of this application and the description of the above figures are intended to cover non-exclusive inclusions.

In the description of the embodiments of the present application, the technical terms "first", "second", and the like are used only for distinguishing different objects, and are not to be construed as indicating or implying relative importance or to implicitly indicate the number, specific order, or primary-secondary relationship of the technical features indicated. In the description of the embodiments of the present application, "a plurality" means two or more unless specifically defined otherwise.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein may be combined with other embodiments.

In the description of the embodiments of the present application, the term "and/or" is only one kind of association relationship describing the association object, and means that three relationships may exist, for example, a and/or B, and may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship.

In the description of the embodiments of the present application, the term "plurality" refers to two or more (including two), and similarly, "plural sets" refers to two or more (including two), and "plural pieces" refers to two or more (including two).

In the description of the embodiments of the present application, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the directions or positional relationships indicated in the drawings, and are only for convenience of description of the embodiments of the present application and for simplicity of description, but do not indicate or imply that the referred device or element must have a specific direction, be constructed and operated in a specific direction, and thus, should not be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise explicitly stated or limited, the terms "mounted," "connected," "fixed," and the like are used in a broad sense, and for example, may be fixedly connected, detachably connected, or integrated; mechanical connection or electrical connection is also possible; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the embodiments of the present application can be understood by those of ordinary skill in the art according to specific situations.

At present, the application of the power battery is more and more extensive from the development of market situation. The power battery is not only applied to energy storage power supply systems such as hydraulic power, firepower, wind power and solar power stations, but also widely applied to electric vehicles such as electric bicycles, electric motorcycles and electric automobiles, and a plurality of fields such as military equipment and aerospace. With the continuous expansion of the application field of the power battery, the market demand is also continuously expanding.

Strict leakproofness will be guaranteed to power battery in the course of the work, if its inside electrolyte is revealed, battery module and battery package not only can be corroded to electrolyte, still can influence the operation of battery, can cause conflagration or explosion even in the serious time. In this regard, at present, the terminal post, the pressure relief member, and other components of the battery are mostly mounted on the end cap of the battery by sealing with the sealing ring. Wherein, the material of sealing washer is rubber usually, and rubber seal takes place deformation under the pressure effect of utmost point post or pressure release piece, because parts such as utmost point post or pressure release piece exert the pressure on rubber seal be invariable, consequently, rubber seal's deformation volume can increase along with the increase of the live time of battery, leads to rubber seal to appear compressive stress relaxation. Thus, when the battery is used for a period of time, the resilience of the rubber sealing ring is weakened, and the sealing performance is weakened. Meanwhile, the resilience force generated by the sealing ring for resisting deformation acts on the pole or the pressure relief piece, so that the pole or the pressure relief piece covering the sealing ring is easy to creep and deform.

Generally speaking, in the full life cycle of battery, rubber seal exists the risk of losing sealing performance, and rubber seal and the utmost point post or the pressure release piece that press to cover rubber seal at this moment appear the gap easily between, and the sealed inefficacy of battery leads to electrolyte to spill over outside the battery from the gap, causes the unable normal operating of battery.

In view of the above problems, embodiments of the present application provide an end cap assembly, a battery cell, a battery, and an electric device, where a terminal post of the end cap assembly is hermetically connected to an end cap through a sealing member, and a compression rate of the sealing member in an initial compression state is configured to be greater than or equal to 10% and less than or equal to 50%.

The end cover assembly disclosed by the embodiment of the application can be used in electric devices such as vehicles, ships or aircrafts, but not limited to. The power supply system with the end cover assembly, the battery and the like disclosed by the application can be used, so that the battery is prevented from losing sealing performance.

The embodiment of the application provides an electric device using a battery as a power supply, wherein the electric device can be but is not limited to a mobile phone, a tablet, a notebook computer, an electric toy, an electric tool, a battery car, an electric automobile, a ship, a spacecraft and the like. The electric toy may include a stationary or mobile electric toy, such as a game machine, an electric car toy, an electric ship toy, an electric airplane toy, etc., and the spacecraft may include an airplane, a rocket, a space shuttle, a spacecraft, etc.

For convenience of description, the following embodiments are described by taking an electric device according to an embodiment of the present application as an example of a vehicle 1000.

Referring to fig. 1, fig. 1 is a schematic structural diagram of a vehicle 1000 according to some embodiments of the present disclosure. The vehicle 1000 may be a fuel automobile, a gas automobile, or a new energy automobile, and the new energy automobile may be a pure electric automobile, a hybrid electric automobile, or a range-extended automobile, etc. The battery 100 is provided inside the vehicle 1000, and the battery 100 may be provided at the bottom or the head or the tail of the vehicle 1000. The battery 100 may be used for power supply of the vehicle 1000, and for example, the battery 100 may serve as an operation power source of the vehicle 1000. The vehicle 1000 may further include a controller 200 and a motor 300, the controller 200 being configured to control the battery 100 to supply power to the motor 300, for example, for starting, navigation, and operational power requirements while the vehicle 1000 is traveling.

In some embodiments of the present application, the battery 100 may be used not only as an operating power source of the vehicle 1000, but also as a driving power source of the vehicle 1000, instead of or in part of fuel or natural gas, to provide driving power for the vehicle 1000.

Referring to fig. 2, fig. 2 is an exploded view of a battery 100 according to some embodiments of the present disclosure. The battery 100 includes a case 10 and a battery cell 20, and the battery cell 20 is accommodated in the case 10. The case 10 is used to provide a receiving space for the battery cells 20, and the case 10 may have various structures. In some embodiments, the case 10 may include a first portion 11 and a second portion 12, the first portion 11 and the second portion 12 cover each other, and the first portion 11 and the second portion 12 together define a receiving space for receiving the battery cell 20. The second part 12 may be a hollow structure with one open end, the first part 11 may be a plate-shaped structure, and the first part 11 covers the open side of the second part 12, so that the first part 11 and the second part 12 jointly define a containing space; the first portion 11 and the second portion 12 may be both hollow structures with one side open, and the open side of the first portion 11 may cover the open side of the second portion 12. Of course, the case 10 formed by the first and second portions 11 and 12 may have various shapes, such as a cylinder, a rectangular parallelepiped, and the like.

In the battery 100, there may be a plurality of battery cells 20, and the plurality of battery cells 20 may be connected in series or in parallel or in series-parallel, where in series-parallel refers to both series connection and parallel connection among the plurality of battery cells 20. The plurality of battery cells 20 can be directly connected in series or in parallel or in series-parallel, and the whole formed by the plurality of battery cells 20 is accommodated in the box body 10; of course, the battery 100 may also be formed by connecting a plurality of battery cells 20 in series, in parallel, or in series-parallel to form a battery module, and then connecting a plurality of battery modules in series, in parallel, or in series-parallel to form a whole, and the whole is accommodated in the box 10. The battery 100 may further include other structures, for example, the battery 100 may further include a bus member for achieving electrical connection between the plurality of battery cells 20.

Wherein each battery cell 20 may be a secondary battery or a primary battery; but is not limited to, a lithium sulfur battery, a sodium ion battery, or a magnesium ion battery. The battery cell 20 may be cylindrical, flat, rectangular parallelepiped, or other shape.

Referring to fig. 3, fig. 3 is an exploded structural schematic diagram of a battery cell 20 according to some embodiments of the present disclosure. The battery cell 20 refers to the smallest unit constituting the battery. Referring to fig. 3, the battery cell 20 includes an end cap assembly 21, a housing 22, a battery cell assembly 23, and other functional components. It should be noted that, for convenience of description, in the drawings of the embodiments of the present application, the directions of the X axis, the Y axis, and the Z axis respectively represent the width direction, the length direction, and the height direction of the battery cell 20.

The housing 22 is an assembly for mating with the end cap assembly 21 to form an internal environment of the battery cell 20, wherein the formed internal environment may be used to house the cell assembly 23, electrolyte, and other components. The housing 22 and the end cap assembly 21 may be separate components, and an opening may be provided in the housing 22, and the opening may be covered by the end cap assembly 21 to form the internal environment of the battery cell 20. Without limitation, the end cap assembly 21 and the housing 22 may be integrated, and specifically, the end cap assembly 21 and the housing 22 may form a common connecting surface before other components are placed in the housing, and when it is required to seal the inside of the housing 22, the end cap assembly 21 covers the housing 22. The housing 22 may be a variety of shapes and sizes, such as rectangular parallelepiped, cylindrical, hexagonal prism, etc. Specifically, the shape of the housing 22 may be determined according to the specific shape and size of the electric core assembly 23. The material of the housing 22 may be various materials, such as copper, iron, aluminum, stainless steel, aluminum alloy, plastic, etc., and the embodiment of the present invention is not limited thereto.

The cell assembly 23 is a component in the battery cell 20 where electrochemical reactions occur. One or more electrical core assemblies 23 may be contained within the housing 22. The core assembly 23 is mainly formed by winding or stacking positive and negative electrode sheets, and a separator is generally provided between the positive and negative electrode sheets. The portions of the positive and negative electrode sheets having the active material constitute the main body portion of the cell assembly 23, and the portions of the positive and negative electrode sheets having no active material each constitute a tab 23a. The positive electrode tab and the negative electrode tab may be located at one end of the main body portion together or at both ends of the main body portion, respectively. During the charge and discharge of the battery, the positive electrode active material and the negative electrode active material react with the electrolyte, and the tab 23a is connected with the pole to form a current loop.

The end cap assembly 21 refers to a member that covers an opening of the case 22 to isolate the internal environment of the battery cell 20 from the external environment. Without limitation, the shape of the end cap assembly 21 may be adapted to the shape of the housing 22 to fit the housing 22.

Fig. 4 is a schematic cross-sectional view of the end cap assembly 21 of some embodiments of the present application with the pole uninstalled and the seal in its original state, and fig. 5 is a schematic cross-sectional view of the end cap assembly 21 of some embodiments of the present application. Referring to fig. 4-5, end cap assembly 21 includes an end cap 210, a post 211, and a seal member 212, end cap 210 having a first face 2101 and a second face 2103 opposite from first face 2101, end cap 210 having a through-hole 2105 extending through first face 2101 and second face 2103; the bottom surface of the pole 211 is hermetically connected with the first surface 2101 through a sealing element 212, and the pole 211 covers the through hole 2105; here, the seal 212 is in a compressed state, and a compression rate of the seal 212 in an initial compressed state is configured to be 10% or more and 50% or less.

The end cap 210 may be a plate-shaped structure, the end cap 210 covers the opening of the housing 22, and the end cap 210 is engaged with the housing 22. The end cap 210 may be made of a material having a certain hardness and strength, so that the end cap assembly 21 has a higher structural strength, and the end cap assembly 21 is not easily deformed when being extruded and collided, so that the safety performance of the battery cell 20 may be improved. For example, the end cap 210 may be made of copper, iron, aluminum, stainless steel, aluminum alloy, or other metal materials. With continued reference to fig. 3, the end cap 210 may further be provided with a functional component such as a pole 211, and the pole 211 may be used to electrically connect with the electric core assembly 23 for outputting or inputting the electric energy of the battery cell 20.

The end cap 210 has a first face 2101 and a second face 2103 opposite in its thickness direction (i.e., Z-axis direction), the first face 2101 facing away from the interior of the battery cell 20 and the second face 2103 facing toward the interior of the battery cell 20. The first surface 2101 refers to the surface of the end cap 210 to which the terminal 211 is attached, and the second surface 2103 refers to the bottom surface of the end cap 210. For example, in the example shown in fig. 4 and 5, the first face 2101 may be the top face of the end cap 210. The end cap 210 is provided with a through hole 2105, and the through hole 2105 penetrates the first surface 2101 and the second surface 2103, so that the through hole 2105 can communicate with the inside of the battery cell 20. The pole 211 is located on the side of the end cap 210 facing away from the inside of the battery cell 20, and the pole 211 covers the through hole 2105.

The sealing member 212 is arranged between the pole 211 and the first surface 2101, the sealing member 212 is annular, and the annular sealing member 212 is arranged around the through hole 2105, so that the sealing member 212 does not block the through hole 2105, and the sealing member 212 is connected with the bottom surface of the pole 211 and the first surface 2101, so that the pole 211 is fixed on the first surface 2101. Thus, the sealing member 212 can seal the through hole 2105 so as not to leak the electrolyte from the through hole 2105 to the outside of the battery 100; meanwhile, the through hole 2105 can allow an adaptor (not shown) to pass through, one end of the adaptor is connected to the tab 23a of the electric core assembly 23, and the other end of the adaptor extends into the through hole 2105 to be connected to the pole 211, so that the current of the electric core assembly 23 can be transmitted to the pole 211.

Wherein the shape of the sealing member 212 is adapted to the shape of the through hole 2105. For example, the through-hole 2105 may be circular, with the seal 212 correspondingly being circular; alternatively, the through hole 2105 may be square, and the sealing member 212 in this case is correspondingly square and annular, which is not limited in this embodiment. The seal 212 may be made from one or more of the following materials: fluororubber, epdm, and nitrile rubber, so that the seal 212 has elasticity. Alternatively, in other embodiments, the seal 212 may be made of a high molecular copolymer. When the sealing member 212 is made of a high molecular copolymer, the high molecular copolymer has good corrosion resistance and aging resistance, so that the sealing member 212 can operate under high temperature conditions for a long period of time.

It is worth noting that the seal 212 is elastically deformed to achieve sealing. Therefore, it can be understood that, as shown in fig. 4, when the sealing member 212 and the post 211 are not mounted on the end cap 210, the sealing member 212 is not subjected to a force, and the sealing member 212 is in an original state, where the thickness of the sealing member 212 is h1 (h 1 > 0); as shown in fig. 5, when the sealing member 212 and the post 211 are mounted on the end cap 210, the sealing member 212 is pressed by the post 211, and the sealing member 212 is changed from the original state to the compressed state, and at this time, the thickness of the sealing member 212 is h2 (h 2 < h 1).

In the present embodiment, the seal 212 is configured such that the compression rate in the initial compressed state is 10% or more and 50% or less. Here, the initial compressed state is a state in which the seal 212 is mounted between the pole 211 and the first surface 2101 and the amount of deformation of the seal 212 is minimum. The compression ratio refers to a rate of change of the seal 212 before and after compression, and specifically, the compression ratio may be calculated as (h 1-h 2)/h 1 × 100%, where h1-h2 is a deformation amount of the seal 212 in a thickness direction when the original state is changed to the initial compression state. Further, the seal 212 is changed from the original state to the compressed state based on the material conservation law, and the portion compressed in the thickness direction thereof is transferred to the lateral direction of the seal 212, so that the cross-sectional area increases while the thickness of the seal 212 decreases. Taking the sealing element 212 as an example of a circular ring shape, the outer diameter of the sealing element 212 in fig. 4 may be d1 (d 1 > 0) in the original state, and the outer diameter of the sealing element 212 in fig. 5 may be increased from d1 to d2 (d 2 > d 1) in the initial compressed state.

For example, in some embodiments, h1 may be designed to be 1.1mm and h2 may be designed to be 0.7mm. In the present example, the compression ratio of the seal 212 in the initial compressed state is (1.1 to 0.7)/1.1 × 100% =36.4%. As another example, in some embodiments, h1 may be designed to be 1.5mm and h2 may be designed to be 0.9mm. In the present example, the compression ratio of the seal 212 in the initial compressed state is (1.5-0.9)/1.5 × 100% =40%.

It can be understood that if the compression rate of the sealing member 212 in the initial compression state is greater than 50%, the amount of deformation of the sealing member 212 in the thickness direction in the initial compression state exceeds half of the thickness of the sealing member 212, so that the sealing member 212 is prone to stress relaxation as the service life of the battery 100 increases, and the resilience of the sealing member 212 is weakened, and the sealing of the battery 100 is prone to failure, and thus the electrolyte leaks. If the compressibility of the seal 212 in the initial compressed state is less than 10%, the amount of deformation of the seal 212 in the initial compressed state is small, the contact pressure between the seal 212 and the electrode post 211 and the first surface 2101 is insufficient, and the sealing performance of the seal 212 is insufficient, and the sealing of the battery 100 is likely to fail, resulting in leakage of the electrolyte.

In the embodiment, the compressibility of the sealing member 212 in the initial compression state is 10% -50%, so that firstly, the compressibility of the sealing member 212 in the early stage of the full life cycle of the battery 100 is not lower than 10%, the compressibility of the sealing member 212 is not too small, the sealing performance of the sealing member 212 is good, and the battery 100 can be kept sealed, secondly, the compressibility of the sealing member 212 in the initial compression state does not exceed 50%, so that even if the deformation amount of the sealing member 212 increases and the compressibility increases along with the increase of the service time of the battery 100, but in the later stage of the full life cycle of the battery 100, the compressibility of the sealing member 212 is not too large to cause stress relaxation of the sealing member 212, so that in the later stage of the full life cycle of the battery 100, the sealing member 212 still can have certain resilience, and the sealing performance of the sealing member 212 cannot be lost, and the battery 100 can be kept sealed. It can be seen that the present embodiment is designed such that the sealing member 212 has good sealing performance during the whole life cycle of the battery 100, thereby being beneficial to reducing the risk of the sealing failure of the battery 100 and being beneficial to improving the safety performance of the battery 100.

It should be noted that, except that the compression ratio of the sealing element 212 between the terminal 211 and the end cap 210 in the initial compression state is 10% to 50%, so as to ensure that the electrolyte does not leak from the through hole 2105 in the whole life cycle of the battery 100, the compression ratios of other sealing elements 212 on the battery 100 in the initial compression state can be 10% to 50%, so that the whole battery 100 has good sealing performance. For example, with continued reference to fig. 4 to fig. 5, the end cap 210 may further include a relief hole 2106 penetrating through the top surface and the second surface 2103 of the end cap 210, the end cap assembly 21 further includes a pressure relief piece 213, the pressure relief piece 213 covers the relief hole 2106, a sealing portion 215 is disposed between the pressure relief piece 213 and the top surface of the end cap 210, and the sealing portion 215 is disposed around the relief hole 2106 to seal the relief hole 2106. The sealing portion 215 may be designed to have a compressibility of 10% to 50% in an initial compressed state, which is advantageous in reducing the possibility of leakage of the electrolyte from the air leakage hole 2106 during the entire life cycle of the battery 100.

According to some embodiments of the present application, the compression rate of the seal 212 in the initial compressed state is configured to be 15% or more and 50% or less.

That is, the compressibility of the seal 212 is not less than 15% and not more than 50% at the beginning of the full life cycle of the battery 100.

By such a design, on the basis of the above embodiment, the lower limit of the compression rate of the sealing member 212 in the initial compression state is increased, and it is further ensured that the compression rate of the sealing member 212 is not too small in the early stage of the full life cycle of the battery 100, so that the sealing member 212 can sufficiently seal the through hole 2105 to prevent the electrolyte from leaking from the battery 100.

Fig. 6 isbase:Sub>A top view of an end cap 210 according to further embodiments of the present application, fig. 7 isbase:Sub>A cross-sectional view of the end cap 210 shown in fig. 6 taken alongbase:Sub>A-base:Sub>A, fig. 8 isbase:Sub>A partial enlarged view of fig. 7 at B, fig. 9 isbase:Sub>A top view of an end cap assembly 21 according to further embodiments of the present application having the end cap 210 shown in fig. 6, fig. 10 isbase:Sub>A cross-sectional view of the end cap assembly 21 shown in fig. 9 taken alongbase:Sub>A direction C-C, and fig. 11 isbase:Sub>A partial enlarged view of fig. 10 at D. Referring to fig. 6 to 11, a mounting groove 2107 is concavely formed on the end cap 210, and a bottom surface of the mounting groove 2107 is a first surface 2101.

Thus, the bottom surface of the post 211 is connected to the bottom surface of the mounting slot 2107 via the seal 212, and the first surface 2101 is spaced apart from the top surface of the end cap 210 in the thickness direction of the end cap 210. By such design, at least a portion of the pole 211 is located in the mounting slot 2107, and specifically, the pole 211 may be completely located in the mounting slot 2107 and does not protrude from the top surface of the end cap 210, or, as shown in fig. 10 and 11, the pole 211 may also be partially located in the mounting slot 2107 and partially protrude from the top surface of the end cap 210.

By designing the mounting groove 2107 on the end cap 210, at least a portion of the terminal 211 is located in the mounting groove 2107, so as to reduce the space occupied by the terminal 211 in the height direction of the battery cell 20. Therefore, on the premise of not changing the total height of the single battery 20, the space inside the single battery 20 can be effectively increased, the number of pole pieces which can be accommodated inside the single battery 20 is increased, and the active material capacity of the single battery 20 is further improved, so that the energy density of the single battery 20 can be improved.

On the basis of the embodiment of providing the mounting groove 2107 on the end cap 210, referring to fig. 8, the distance between the first surface 2101 and the second surface 2103 along the thickness direction of the end cap 210 is a first distance H1, and the first distance H1 may be designed to be greater than or equal to 1mm.

That is, the thickness of the bottom wall of the mounting groove 2107 is 1mm or more. Illustratively, the first distance H1 may be 1mm, 1.2mm, or 1.5mm, which is not limited by the present embodiment.

It can be understood that the strength of the end cap 210 with the mounting groove 2107 is weaker than the strength of the position without the mounting groove, and in this embodiment, the distance between the first surface 2101 and the second surface 2103 is greater than or equal to 1mm, so as to ensure that the position on the end cap 210 with the mounting groove 2107 still has a certain strength, so that the end cap 210 has a higher structural strength, and the safety performance of the battery 100 can be ensured. Furthermore, the resilience generated by the deformation of the sealing member 212 also acts on the first surface 2101, and by designing the distance between the first surface 2101 and the second surface 2103 to be equal to or greater than 1mm, the possibility that the groove bottom wall of the mounting groove 2107 is subjected to creep deformation due to the resilience for a long time is low in the full life cycle of the battery 100.

In combination with the foregoing, by forming the mounting groove 2107 on the end cover 210 and designing the thickness of the bottom wall of the mounting groove 2107 to be greater than or equal to 1mm, on the premise that the bottom wall of the mounting groove 2107 meets the creep requirement, the height of the pole 211 protruding from the top surface of the end cover 210 is reduced as much as possible, so as to increase the space utilization rate of the battery cell 20 in the height direction.

With continued reference to fig. 8, the area of the second face 2103 of the end cap 210 corresponding to the mounting slot 2107 is provided with a raised portion 2104 protruding toward the interior of the battery cell 20.

The projection 2104 may be plate-shaped, block-shaped, or other shapes. The protrusion 2104 and the end cap 210 may be an integral component formed by an integral molding process, so that the structural strength of the end cap 210 may be improved without increasing the cost. Thus, the bottom surface of the end cap 210 is not flat, and the area of the bottom surface of the end cap 210 where the protrusions 2104 are provided is raised over the other areas.

By designing the projection 2104, the strength of the position of the end cover 210 where the mounting groove 2107 is formed is improved, so that the end cover 210 has high structural strength, and the safety performance of the battery 100 is ensured.

With continued reference to fig. 9 and 11, the end cap assembly 21 further includes a fixture 214, the fixture 214 is a solid of revolution, the fixture 214 surrounds the pole 211 and the sealing member 212, and the fixture 214 is connected to the first surface 2101.

The fixture 214 at least partially surrounds the pole 211, and the fixture 214 is coupled to the first face 2101 of the end cap 210 such that the pole 211 can be coupled to the end cap 210 by the fixture 214. In the example shown in fig. 11, the fixing member 214 may specifically include a first fixing member 2141 and a second fixing member 2142, the first fixing member 2141 at least partially surrounds the pole 211, such that the pole 211 is fixed to the first fixing member 2141, the second fixing member 2142 is connected to the first fixing member 2141, and the second fixing member 2142 is tightly connected to the first surface 2101, so as to fix the pole 211 and the first fixing member 2141 to the end cover 210. The first fixing part 2141 and the second fixing part 2142 may both be a rigid plastic part or a metal part, so that the fixing part 214 has higher structural strength to improve the connection stability of the terminal 211.

Through setting up mounting 214, utmost point post 211 can be fixed in end cover 210 through the connection of mounting 214, and then is favorable to improving utmost point post 211's installation stability.

The mounting groove 2107 may specifically include a first sub-groove 2107a and a second sub-groove 2107b, the cross-sectional area of the first sub-groove 2107a is larger than that of the second sub-groove 2107b, and the bottom surface of the second sub-groove 2107b is a first surface 2101; the bottom surface of the first sub-groove 2107a and the side surface of the second sub-groove 2107b form a step, and the step has a step surface and a step side wall, and the fixing member 214 abuts against the step side wall of the step.

The bottom surface of the first sub-groove 2107a is a step surface, and the side surface of the second sub-groove 2107b is a step side wall. In the thickness direction of the end cap 210, the depth of the first sub-groove 2107a may be H2, and the depth of the second sub-groove 2107b may be H3, so that the thickness H4 of the end cap 210 is the sum of the depth H2 of the first sub-groove 2107a, the depth H3 of the second sub-groove 2107b, and the first distance H1, that is, H4= H1+ H2+ H3. The thickness H4 of the end cap 210 can be understood as the distance between the top surface of the end cap 210 and the second surface 2103 of the end cap 210 along the thickness direction. Illustratively, H1 may be 1mm, H2 may be 0.7mm, H3 may be 0.8mm, and the thickness H4 of the end cap 210 may be 2.5mm.

The cross-sectional area of the first sub-slot 2107a is greater than the cross-sectional area of the second sub-slot 2107b includes, but is not limited to, a variety of possible implementations. For example, in a possible implementation, when the orthographic projection shapes of the first sub-slot 2107a and the second sub-slot 2107b on the top surface of the end cap 210 are both circular, the diameter of the first sub-slot 2107a can be designed to be larger than the diameter of the second sub-slot 2107 b.

Thus, the anchor 214 is connected not only to the first surface 2101 but also to the groove side surface of the second sub-groove 2107b, and the strength of connection between the anchor 214 and the end cap 210 is improved, and the stability of connection between the pole 211 and the end cap 210 is further improved. Moreover, by designing the cross-sectional area of the first sub-groove 2107a to be larger than the cross-sectional area of the second sub-groove 2107b, tool withdrawal is facilitated when the first sub-groove 2107a and the second sub-groove 2107b are machined.

In the example shown in fig. 11, the bottom surface of the fixing member 214 may further be concavely formed with a groove 2143, and a groove wall of the groove 2143 and the outer circumferential surface of the sealing member 212 in the original state together define an escape space configured to accommodate a compression amount by which the sealing member 212 is compressed from the original state to the original compressed state.

As can be seen from the foregoing, when the seal 212 is compressed according to the law of conservation of mass, the portion of the seal 212 compressed in the thickness direction is deformed in the lateral direction of the seal 212, and the cross-sectional area increases while the thickness of the seal 212 decreases. In the embodiment, the groove 2143 is formed in the bottom surface of the fixing member 214, and the groove 2143 and the outer peripheral surface of the sealing member 212 together define an escape space, which can accommodate the compression amount of the sealing member 212 from the original state to the initial compression state. Portions of the seal 212 may be received within the relief space when the seal 212 is in a compressed state.

The specific implementation of the escape space configured to accommodate the amount of compression of the seal 212 from the original state to the initial compressed state is as follows: the volume of the relief space is designed to be no less than the volume of the compression of the seal 212 from the initial state to the initial compressed state.

By such design, in the assembling process of the end cap assembly 21, the sealing member 212 is pressed by the pole 211, the original state is changed into the initial compression state, and the escape space surrounded by the groove 2143 of the fixing member 214 and the outer peripheral surface of the sealing member 212 can accommodate the compression amount of the sealing member 212, so that the fixing member 214 does not interfere with the deformed sealing member 212.

The sealing element 212 is a circular ring-shaped sealing ring, the cross section of the groove 2143 is circular, and the deformation and avoidance space of the sealing ring from the original state to the initial compression state satisfy:

；

wherein, R1 is the inner diameter of the sealing ring in the original state, R2 is the outer diameter of the sealing ring in the original state, R3 is the inner diameter of the groove 2143, H1 is the thickness of the sealing ring in the original state, H2 is the thickness of the sealing ring in the initial compression state, and H5 is the depth of the groove 2143.

For example, taking the sealing element 212 as a circular ring, the orthographic projection shape of the groove 2143 on the second face 2103 of the end cap 210 as a circle, setting the thickness of the sealing element 212 in the original state as h1, the inner diameter of the sealing element 212 in the original state as R1, the outer diameter of the sealing element 212 in the original state as R2, the thickness of the sealing element 212 in the initial compression state as h2, and R1 < R2, it can be understood that the volume of the compression amount of the sealing element 212 changed from the original state to the initial compression state is the volume corresponding to the amount of the compression deformation, and the calculation formula of the compression amount can be as follows

。

Setting the inner diameter of the groove 2143 to be R3, and the depth of the groove 2143 to be H5, where the groove 2143 and the sealing element 212 together enclose an annular avoidance space, and a volume calculation formula of the annular avoidance space may be

. Wherein H5 is equal to or greater than H2, so that the compressed portion of the seal 212 can enter the escape space.

Design of

In this way, the volume of the escape space is not less than the compression amount by which the seal 212 is compressed from the original state to the initial compressed state, and the escape space can accommodate the compression amount of the seal 212.

Illustratively, R1 may be 18.7mm, R2 may be 20mm, R3 may be 21.6mm, and H5 may be 0.7mm. As described earlier, h1 is 1.1mm and h2 is 0.7mm. Thus, the volume of the compression amount of the seal member 212 is 15.8mm ³ The volume of the avoiding space is 36.6 mm ³ I.e., the volume of the clearance space is greater than the volume of the compression of the seal 212. It will be understood by those skilled in the art that if the sealing member 212 is square ring shaped, the design principle is similar and will not be described herein.

FIG. 12 is a partial cross-sectional schematic view of an end cap assembly 21 according to further embodiments of the present application. Referring to fig. 12, an annular boss 2102 is protruded from the first surface 2101, and the annular boss 2102 is arranged around the through hole 2105; the sealing member 212 comprises a first sealing portion 2121 and a second sealing portion 2122 connected, wherein the first sealing portion 2121 abuts between the bottom surface of the pole 211 and the first surface 2101, and the second sealing portion 2122 abuts between the bottom surface of the pole 211 and the annular boss 2102.

The annular boss 2102 protrudes from the first surface 2101, and the annular boss 2102 and the end cap 210 may be of an integral structure formed by an integral molding process, or the annular boss 2102 and the end cap 210 may also be of a split structure. Here, the first seal portion 2121 may have a gap from the outer peripheral side surface of the annular boss 2102, or the first seal portion 2121 may abut against the outer peripheral side surface of the annular boss 2102. In the embodiment in which there is a gap between the first sealing portion 2121 and the outer circumferential side surface of the annular boss 2102, the positive electrode active material structure changes, the electrolyte decomposes, heat is generated, and the temperature of the first sealing portion 2121 rises to expand when the battery cell 20 is charged, and the gap can provide a space for deformation of the first sealing portion 2121.

It should be noted that, in the present embodiment, during the assembly process of the end cap assembly 21, the sealing element 212 changes from the original state to the compressed state, the compressed amount of the first sealing portion 2121 can be pressed into the groove 2143, and the compressed amount of the second sealing portion 2122 can be pressed into the through hole 2105.

Through setting up annular boss 2102, the peripheral side of annular boss 2102 is located to sealing member 212 cover, and then annular boss 2102 can play certain limiting displacement to sealing member 212 to restriction sealing member 212 appears the drunkenness phenomenon along the radial direction of through-hole 2105 and leads to breaking away from between utmost point post 211 and the first face 2101, is favorable to improving the sealed effect of sealing member 212 to through-hole 2105.

Further, the seal 212 may further include an annular sealing portion 2123, the annular sealing portion 2123 is connected to the second sealing portion 2122, and the annular sealing portion 2123 is mounted in the through hole 2105.

The annular seal portion 2123 is fitted into the through hole 2105, and a gap may be provided between the annular seal portion 2123 and the hole wall of the through hole 2105, or the annular seal portion 2123 may abut against the hole wall of the through hole 2105. In the embodiment where there is a gap between the annular seal portion 2123 and the wall of the through-hole 2105, the positive active material structure changes, the electrolyte decomposes, heat is generated, and the temperature of the seal member 212 rises to expand when the battery cell 20 is charged, and this gap can provide a space for deformation of the annular seal portion 2123 so that the expanded annular seal portion 2123 abuts against the wall of the through-hole 2105.

Like this, on the one hand, when the adaptor stretches into through-hole 2105 and is connected with utmost point post 211, annular sealing portion 2123 can separate adaptor and end cover 210 contact, and then be favorable to avoiding electric core subassembly 23 to transmit the electric energy guide to utmost point post 211 on end cover 210 to guarantee battery 100's safety, on the other hand, through setting up annular sealing portion 2123, sealing member 212 is the crotch form, and annular boss 2102 is hitched to crotch form sealing member 212, in order to improve sealing member 212's installation stability.

As shown in fig. 12, in one particular embodiment, the end cap assembly 21 includes an end cap 210, a post 211, a sealing member 212, and a retainer 214, the end cap 210 having a first face 2101 and a second face 2103 opposite each other, the first face 2101 facing away from the interior of the battery cell 20, the end cap 210 having a through-hole 2105 extending through the first face 2101 and the second face 2103; the bottom surface of the pole 211 is hermetically connected with the first surface 2101 through a sealing element 212, and the pole 211 covers the through hole 2105; here, the seal 212 is in a compressed state, and a compression rate of the seal 212 in an initial compressed state is configured to be 10% or more and 50% or less.

The fixing member 214 is a rotation body, the fixing member 214 surrounds the pole 211 and the sealing member 212, the fixing member 214 is connected to the first surface 2101, a groove 2143 is concavely formed on the bottom surface of the fixing member 214, a groove wall of the groove 2143 and the outer peripheral surface of the sealing member 212 jointly define an escape space, and the escape space is configured to accommodate a compression amount of the sealing member 212 from an original state to an initial compression state.

The end cover 210 is concavely formed with a mounting groove 2107, the bottom surface of the mounting groove 2107 is a first surface 2101, an annular boss 2102 is convexly arranged on the first surface 2101, and the annular boss 2102 is arranged around the through hole 2105. The sealing member 212 comprises a first sealing portion 2121, a second sealing portion 2122 and an annular sealing portion 2123 which are sequentially connected, the first sealing portion 2121 abuts between the bottom surface of the pole 211 and the first surface 2101, the second sealing portion 2122 abuts between the bottom surface of the pole 211 and the annular boss 2102, and the annular sealing portion 2123 is mounted in the through hole 2105.

Finally, it should be noted that: the above embodiments are only used for illustrating the technical solutions of the present application, and not for limiting the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; these modifications and substitutions do not depart from the spirit of the embodiments of the present application, and they should be construed as being included in the scope of the claims and description of the present application. In particular, the technical features mentioned in the embodiments can be combined in any way as long as there is no structural conflict. The present application is not intended to be limited to the particular embodiments disclosed herein but is to cover all embodiments that may fall within the scope of the appended claims.

Claims (14)

1. An end cap assembly for a battery cell, comprising:

the end cover is provided with a first surface and a second surface which are opposite, the first surface faces back to the interior of the battery monomer, and a through hole penetrating through the first surface and the second surface is formed in the end cover;

the bottom surface of the pole is connected with the first surface in a sealing mode through a sealing element, and the pole covers the through hole; wherein the seal is in a compressed state, and a compression rate of the seal in an initial compressed state is configured to be 10% or more and 50% or less.

2. The end cap assembly of claim 1, wherein the compression ratio of the seal in the initial compressed state is configured to be 15% or greater and 50% or less.

3. The end cap assembly of claim 1, wherein the end cap recess is formed with a mounting groove, a groove bottom surface of the mounting groove being the first face.

4. An end cap assembly according to claim 3, wherein the second face is a bottom face of the end cap, and a distance between the first face and the second face in a thickness direction of the end cap is a first distance, the first distance being greater than or equal to 1mm.

5. An end cap assembly according to claim 3, wherein a region of the second face of the end cap corresponding to the mounting groove is convexly provided with a boss toward the inside of the battery cell.

6. The end cap assembly of claim 3, further comprising a fastener surrounding the pole and the seal member, the fastener being coupled to the first face.

7. The end cap assembly of claim 6, wherein the mounting slot includes a first sub-slot and a second sub-slot, the first sub-slot having a cross-sectional area greater than a cross-sectional area of the second sub-slot, the second sub-slot having a slot floor that is the first face;

the groove bottom surface of the first subslot and the groove side surface of the second subslot jointly form a step, and the fixing piece is abutted to the step side wall of the step.

8. An end cap assembly according to claim 6, wherein the bottom surface of the fixing member is recessed to form a groove, and a groove wall of the groove and the outer peripheral surface of the sealing member in the original state together define an escape space configured to accommodate a deformation amount of the sealing member from the original state to the original compressed state.

9. The end cap assembly of claim 8, wherein the sealing element is a ring-shaped sealing ring, the cross-sectional shape of the groove is circular, and the deformation of the sealing ring from the original state to the initial compressed state satisfies the avoidance space:

;

wherein, R1 is the inner diameter of the seal ring in an original state, R2 is the outer diameter of the seal ring in an original state, R3 is the inner diameter of the groove, H1 is the thickness of the seal ring in an original state, H2 is the thickness of the seal ring in an initial compression state, and H5 is the depth of the groove.

10. An end cap assembly according to any one of claims 1 to 9, wherein an annular boss projects from the first face, the annular boss being disposed around the through-hole;

the sealing member includes continuous first sealing and second sealing, first sealing butt in the bottom surface of utmost point post with between the first face, second sealing butt in the bottom surface of utmost point post with between the annular boss.

11. The end cap assembly of claim 10, wherein the seal further comprises an annular seal portion connected to the second seal portion and mounted within the through hole.

12. A battery cell comprising an end cap assembly according to any one of claims 1 to 11.

13. A battery comprising the cell of claim 12.

14. An electric consumer, characterized in that the electric consumer comprises a battery according to claim 13 for providing electric energy.

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