Energy storage device and energy storage system
By setting a ventilated structure on the cover plate patch, the problem of unbalanced air pressure during the heating process of the battery end cover was solved, ensuring the finished product quality and pass rate of the energy storage device.
Patent Information
- Application Number
- CN202422829800.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-11-25
- Estimated Expiration
- 2034-11-20
AI Technical Summary
During the heating process of the battery end cap, the imbalance of air pressure inside and outside the cavity at the injection hole causes the end cap patch to bulge or dent, affecting the battery's pass rate.
Ventilation structures, such as slits or through holes, are installed on the cover plate patch to ensure the internal and external air pressure balance at the injection hole. The ventilation structure allows for air to be vented or inhaled, preventing bulging or denting caused by air pressure changes.
This achieves pressure balance at the injection port, avoids bulging or denting of the end cap patch, and improves the finished product quality and pass rate of the energy storage device.
Smart Images
Figure CN223598990U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to energy storage technology field especially, relates to a kind of energy storage device and energy storage system. BACKGROUND
[0002] The battery end cover in the related art is usually provided with a liquid injection hole, so that electrolyte can be injected into the inside of the battery through the liquid injection hole, so that the bare battery cell inside the battery can be soaked in the electrolyte. In order to ensure that the bare battery cell can be placed in a sealed space after the liquid injection is completed, the liquid injection hole is usually sealed by using a glue pin.
[0003] In order to avoid the glue pin from loosening due to accidental touch and affect the sealing effect of the glue pin on the liquid injection hole, the glue pin is usually made to be lower than the surface of the battery end cover and not protrude from the surface of the battery end cover to form a counterbore. After the end cover patch is pasted on the surface of the battery end cover, the counterbore will form a closed cavity after the end cover patch is pasted. According to the production process in the related art, the end cover patch is pasted, and then a heat-shrinkable film is wrapped. The battery wrapped with the film is heated to achieve the purpose of heat shrinkage.
[0004] However, during the heating process, the air inside the cavity will expand due to heat, causing the end cover patch to bulge, which will increase the number of defective products. After the battery is heated, the air inside the cavity will contract when it is naturally cooled or in a low-temperature environment, forming a negative pressure inside the cavity and causing the end cover patch to sag, which will also increase the number of defective products and affect the pass rate of the battery. SUMMARY
[0005] The utility model embodiment discloses an energy storage device and an energy storage system, which can keep the internal and external air pressures consistent at the position of the liquid injection hole after the end cover plate is pasted with the cover plate patch, and avoid the problems of bulging or sagging.
[0006] To achieve the above-mentioned purpose, in a first aspect, the utility model discloses an energy storage device, which comprises:
[0007] A shell having an inner cavity and an opening communicating with the inner cavity;
[0008] A bare battery cell built-in the inner cavity;
[0009] An end cover plate sealed at the opening, the end cover plate having a first surface and a second surface opposite in the thickness direction, the first surface being arranged away from the bare battery cell, and the end cover plate being provided with a liquid injection hole penetrating through the first surface and the second surface;
[0010] A sealing member is arranged at the liquid injection hole and is lower than the first surface in a direction from the second surface to the first surface, so that the sealing member and a hole wall surface of the liquid injection hole enclose a counterbore.
[0011] A cover patch is attached to the first surface and covers the counterbore, and the cover patch is provided with a gas permeable structure communicating with the counterbore.
[0012] In the energy storage device provided in the application, the gas permeable structure is arranged on the cover patch and communicates with the counterbore (i.e. the liquid injection hole), so that the counterbore can exhaust gas through the gas permeable structure when the energy storage device is heated for thermal shrinkage, or the energy storage device can intake air through the gas permeable structure when the energy storage device is naturally cooled or in a low-temperature environment, so as to balance the internal and external air pressures, thereby avoiding the problem of bulging or depression at the position of the counterbore corresponding to the cover patch, ensuring the finished product quality of the energy storage device, and further improving the qualified rate of the energy storage device.
[0013] As an optional implementation, in the embodiment of the first aspect of the application, a projection of the gas permeable structure on the end cover plate is a first projection in the thickness direction of the end cover plate, and a projection of the sealing member on the end cover plate is a second projection, and the second projection at least partially overlaps the first projection.
[0014] In this way, the path for the gas in the counterbore to exhaust out of the counterbore or the path for the external gas to enter the counterbore is approximately equal to the thickness of the cover patch, and since the thickness of the end cover plate is usually thin, the path for the gas in the counterbore to exhaust out of the counterbore or the path for the external gas to enter the counterbore is relatively short, so that the internal and external air pressures at the counterbore can be quickly balanced, and the problem of bulging or depression at the position of the counterbore corresponding to the cover patch can be effectively avoided.
[0015] As an optional implementation, in the embodiment of the first aspect of the application, the gas permeable structure is formed as a slit on the cover patch.
[0016] By arranging the slit, the counterbore can exhaust or intake gas through the slit to balance the internal and external air pressures, so as to meet the demand that the position of the counterbore corresponding to the cover patch is gas permeable, and since the slit width is usually small and not easy to be seen by the naked eye, the appearance of the cover patch is not greatly affected, and the cover patch can have almost no difference in appearance from the original design, so that the original appearance design is maintained.
[0017] As an optional implementation, in the embodiment of the first aspect of the utility model, the cut includes a first cut and a second cut, and the first cut and the second cut are arranged in a cross manner.
[0018] By arranging the cut in a cross manner, the first cut and the second cut can divide the cover patch into four fan-shaped areas, and when the energy storage device is heated to achieve thermal contraction, the gas in the counterbore can lift the fan-shaped areas divided by the first cut and the second cut outward, so that the gas in the counterbore can be better discharged outward, or when the heated energy storage device is naturally cooled or in a low-temperature environment, the gas outside the counterbore can lift the fan-shaped areas divided by the first cut and the second cut inward, so that the gas outside the counterbore can better enter the counterbore, achieving rapid balance of the air pressure inside and outside the counterbore and effectively avoiding the problem of bulging or depression at the position of the counterbore corresponding to the cover patch.
[0019] As an optional implementation, in the embodiment of the first aspect of the utility model, the length of the cut is 1mm-10mm.
[0020] By controlling the length of the cut within the range of 1mm-10mm, the cut can have a certain length, so that when the energy storage device is heated, the space for the counterbore to release gas outward is larger, and when the heated energy storage device is naturally cooled or in a low-temperature environment, the space for the external gas to enter the counterbore is larger, which can better achieve balance of the air pressure inside and outside the counterbore; and the length of the cut can be prevented from being too long to affect the appearance of the cover patch.
[0021] As an optional implementation, in the embodiment of the first aspect of the utility model, the air-permeable structure is formed as a through hole on the cover patch.
[0022] By arranging the through hole, the counterbore can discharge or intake air through the through hole to achieve the effect of balancing the air pressure inside and outside, meet the demand that the position of the counterbore corresponding to the cover patch can be permeable, and the air permeation effect is better; at the same time, the through hole is relatively simple in processing technology and is relatively easy to process in technology, which is beneficial to simplify the processing technology of the cover patch.
[0023] As an optional implementation, in the embodiment of the first aspect of the utility model, the shape of the through hole is circular, and the diameter of the through hole is 1mm-2mm.
[0024] By controlling the diameter of the through hole in the range of 1mm-2mm, the through hole can have a certain diameter, so that when the energy storage device is heated, the space for the counterbore to release gas outward is large, and when the heated energy storage device is naturally cooled or in a low temperature environment, the space for the external gas to enter the gas space in the counterbore is large, which can better realize the balance of the air pressure inside and outside the counterbore; and the diameter of the through hole can be prevented from being too long to affect the appearance of the cover plate patch.
[0025] As an optional implementation, in the embodiment of the first aspect of the utility model, the energy storage device further comprises a glue layer, the cover plate patch is bonded to the first surface through the glue layer, and the air permeable structure is formed as an air permeable groove on the glue layer; the air permeable groove extends from the counterbore to the edge position of the cover plate patch to form an air permeable opening at the edge position of the cover plate patch; or, the end cover plate is provided with an explosion-proof valve and / or an identification part, the cover plate patch is provided with a window exposing the explosion-proof valve and / or the identification part, and the air permeable groove extends from the counterbore to communicate with the window.
[0026] By setting the air permeable groove on the glue layer on the back of the cover plate patch to form the air permeable structure, the air permeable structure cannot be seen in appearance, so that the cover plate patch has no change in appearance on the basis of meeting the air permeation demand of the cover plate patch at the position where the counterbore is located, and the appearance integrity of the energy storage device is maintained.
[0027] As an optional implementation, in the embodiment of the first aspect of the utility model, the length of the air permeable groove in the extension direction thereof is 6mm-24mm; and / or, in the direction perpendicular to the thickness direction of the end cover plate and the extension direction of the air permeable groove, the width of the air permeable groove is 1mm-5mm; and / or, in the thickness direction of the end cover plate, the thickness of the cover plate patch is h0, the depth of the air permeable groove is h1, and h1=0.2h0-0.5h0.
[0028] By controlling the length of the air permeable groove in the extension direction thereof in the range of 6mm-24mm, it is ensured that the air permeable groove can extend to the edge position of the cover plate patch to form an air permeable opening, or extend to the window to communicate with the window, so as to meet the air permeation demand of the cover plate patch at the position where the counterbore is located.
[0029] By controlling the width of the air permeable groove in the range of 1mm-5mm, the air permeable groove can have a certain width, so that when the energy storage device is heated, the space for the counterbore to release gas outward is large, and when the heated energy storage device is naturally cooled or in a low temperature environment, the space for the external gas to enter the gas space in the counterbore is large, which can better realize the balance of the air pressure inside and outside the counterbore; and the cover plate patch and the end cover plate can have a certain area of glue to ensure the bonding stability between the cover plate patch and the end cover plate.
[0030] By controlling the depth of the air venting groove in the range of 20%-50% of the cover patch, the air venting groove has a certain depth, so that when the energy storage device is heated, the counterbore has a larger space for releasing gas outward, and when the heated energy storage device is naturally cooled or in a low temperature environment, the outside gas has a larger space for entering the gas space in the counterbore, so that the air pressure balance inside and outside the counterbore can be better realized; and the position of the adhesive layer corresponding to the air venting groove has a certain thickness, supporting the cover patch, and avoiding the problem of depression of the cover patch at the position corresponding to the air venting groove.
[0031] In the second aspect, the utility model discloses a kind of energy storage systems, and the energy storage system has the energy storage device as described in the above first aspect. The energy storage system with the energy storage device described in the above first aspect can also realize that the air pressure inside and outside the position of injection hole of end cover plate is consistent after pasting cover patch, to avoid the problem of bulging or depression.
[0032] Compared with the prior art, the utility model has the beneficial effects that:
[0033] The energy storage device and energy storage system provided by the utility model embodiment, by being provided with the air venting structure communicated with the counterbore (i.e. injection hole) on the cover patch, so that when the energy storage device is heated to achieve thermal shrinkage, the counterbore can be vented through the air venting structure, or when the heated energy storage device is naturally cooled or in a low temperature environment, the counterbore can be ventilated through the air venting structure to achieve the effect of air pressure balance inside and outside, so as to avoid the problem of bulging or depression of the cover patch at the position corresponding to the counterbore, to ensure the finished product quality of the energy storage device, and further to facilitate improving the qualified rate of the energy storage device. BRIEF DESCRIPTION OF DRAWINGS
[0034] In order to more clearly illustrate the technical scheme in the utility model embodiment, the drawings needed to be used in the embodiment will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained by those skilled in the art without creative labor.
[0035] Figure 1 is the first structure schematic view of the energy storage system disclosed by the utility model embodiment;
[0036] Figure 2 is the second structure schematic view of the energy storage system disclosed by the utility model embodiment;
[0037] Figure 3 is the structure schematic view of the energy storage device disclosed by the utility model embodiment;
[0038] Figure 4 is a sectional view along the direction of A-A in Figure 3
[0039] Figure 5 is an enlarged view of M in Figure 4
[0040] Figure 6 is a first exploded structural schematic view of the end cover plate and the cover plate patch according to an embodiment of the present application;
[0041] Figure 7 is an enlarged view of N in Figure 6
[0042] Figure 8 is a second exploded structural schematic view of the end cover plate and the cover plate patch according to an embodiment of the present application;
[0043] Figure 9 is an enlarged view of O in Figure 8
[0044] Figure 10 is a third exploded structural schematic view of the end cover plate and the cover plate patch according to an embodiment of the present application;
[0045] Figure 11 is an exploded structural schematic view of the end cover plate and the cover plate patch from another perspective in Figure 10
[0046] Figure 12 is a fourth exploded structural schematic view of the end cover plate and the cover plate patch according to an embodiment of the present application;
[0047] Figure 13 is a fifth exploded structural schematic view of the end cover plate and the cover plate patch according to an embodiment of the present application;
[0048] Figure 14 is a sixth exploded structural schematic view of the end cover plate and the cover plate patch according to an embodiment of the present application;
[0049] Figure 15 is a structural schematic view of the glue layer according to an embodiment of the present application.
[0050] Main figure mark explanation
[0051] 1000 - energy storage system
[0052] 100 - energy storage device; 11 - housing; 111 - inner cavity; 112 - opening; 12 - bare cell; 13 - end cover plate; 13a - first surface; 13b - second surface; 131 - liquid injection hole; 132 - counterbore; 133 - explosion-proof valve; 134 - identification part; 14 - sealing member; 141 - glue nail; 142 - sealing aluminum sheet; 15 - cover plate patch; 151 - air permeable structure; 151a - cut seam; 151a1 - first cut seam; 151a2 - second cut seam; 151b - through hole; 152 - window; 152a - first window; 152b - second window; 16 - glue layer; 161 - air permeable groove; 161a - first air permeable groove; 161b - second air permeable groove; 162 - air permeable hole.
[0053] 200 - electric energy conversion device; 300 - first user load; 400 - second user load;
[0054] 210 - high-voltage cable; 310 - first electric energy conversion device; 410 - second electric energy conversion device. DETAILED DESCRIPTION
[0055] In order to make the purposes, technical solutions and advantages of the present application clearer, the following will combine the drawings in the exemplary embodiments of the present application to clearly and completely describe the exemplary embodiments of the present application. Obviously, the described exemplary embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. That is, the specific embodiments described herein are only used to explain the present application, and are not intended to limit the embodiments of the present application.
[0056] It should be noted that the brief description of the terms in the present application is only for the convenience of understanding the subsequently described embodiments, and is not intended to limit the embodiments of the present application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by those skilled in the art to which the present application belongs. The terms used in the specification of the present application are only for the purpose of describing the specific embodiments, and are not intended to limit the present application.
[0057] In the description of the present application, it should be understood that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and are not intended to indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.
[0058] The terms "first", "second", and the like used in the present application can be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element. For example, without departing from the scope of the present application, a first surface can be referred to as a second surface, and similarly, a second surface can be referred to as a first surface. Both the first surface and the second surface are surfaces, but they are not the same surface.
[0059] In addition, the terms "first", "second" are only for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specified.
[0060] In the description of the present application, it should be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connection" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.
[0061] In the description of the present application, it should be noted that the singular form "one", "an" and "said / this" can also include the plural form, unless the context clearly indicates otherwise. It should also be understood that the terms "include / contain" or "have" and the like specify the existence of the stated features, integers, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the existence or addition of one or more other features, integers, steps, operations, components, parts or combinations thereof.
[0062] In addition, the term "and / or" used in the specification includes any and all combinations of the related listed items, for example, A and / or B can mean: A exists alone, A and B exist together, B exists alone, that is, the term "and / or" used in the specification includes any and all combinations of the related listed items.
[0063] Since the energy required by people has strong time and space, in order to reasonably use energy and improve the utilization rate of energy, it is necessary to store one form of energy into the same or another form of energy through a medium or device, and release it in a specific energy form based on future application needs. It is well known that the main way to generate green electricity at present is to develop green energy such as photovoltaic and wind power to replace fossil energy.
[0064] Currently, the generation of green electricity generally relies on solar, wind, and hydropower. However, wind and solar power are generally characterized by strong intermittency and large fluctuations, which can cause grid instability, insufficient electricity during peak demand periods, and excessive electricity during off-peak periods. Unstable voltage can also damage the power grid. Therefore, insufficient electricity demand or insufficient grid capacity may lead to the problem of "wind and solar curtailment." To solve these problems, energy storage is necessary. This involves converting electrical energy into other forms of energy through physical or chemical means and storing it, then releasing the energy back into electricity when needed. Simply put, energy storage is like a large "power bank," storing electrical energy when solar and wind power are abundant and releasing the stored electricity when needed.
[0065] Taking electrochemical energy storage as an example, this application provides an energy storage device. The energy storage device is equipped with a set of energy storage batteries. It mainly uses the chemical elements in the battery as the energy storage medium. The charging and discharging process is accompanied by the chemical reaction or change of the energy storage medium. Simply put, it stores the electrical energy generated by wind and solar energy in the chemical battery. When the use of external electrical energy reaches its peak, the stored electricity is released for use, or transferred to places with a shortage of electricity for use.
[0066] Current energy storage applications are quite widespread, including generation-side energy storage, grid-side energy storage, renewable energy grid-connected energy storage, and user-side energy storage. The corresponding types of energy storage devices include:
[0067] ① Large energy storage containers used in grid-side energy storage scenarios can serve as high-quality active and reactive power regulation power sources in the grid, enabling load matching of electrical energy in time and space, enhancing the absorption capacity of renewable energy, and playing a significant role in grid system backup, alleviating peak load power supply pressure, and peak and frequency regulation.
[0068] ② Small and medium-sized energy storage cabinets used in commercial and industrial energy storage scenarios (banks, shopping malls, etc.) and small residential energy storage boxes used in residential energy storage scenarios primarily operate under the "peak shaving and valley filling" model. Because there are significant price differences in electricity during peak and off-peak periods based on demand, users with energy storage devices typically charge the cabinets / boxes during off-peak hours and release the stored electricity during peak hours to save on costs. Furthermore, in remote areas and regions prone to natural disasters such as earthquakes and hurricanes, residential energy storage devices essentially provide backup power for users and the power grid, eliminating the inconvenience caused by frequent power outages due to disasters or other reasons.
[0069] Please see Figure 1 , Figure 1The energy storage system provided in one embodiment of this application is a structural schematic diagram of a residential energy storage system, and this application... Figure 1 The embodiments are illustrated using a home energy storage scenario in user-side energy storage as an example. The energy storage device provided in the embodiments of this application is not limited to the home energy storage scenario.
[0070] like Figure 1 As shown, the energy storage system 1000 provided in this embodiment includes an energy storage device 100, a power conversion device 200 (photovoltaic panel), a first user load 300 (streetlight), and a second user load 400 (e.g., household appliances such as air conditioners). The energy storage device 100 is a small energy storage box that can be wall-mounted to an outdoor wall. Specifically, the photovoltaic panel can convert solar energy into electrical energy during periods of low electricity prices, and the energy storage device 100 is used to store this electrical energy and supply it to streetlights and household appliances during peak electricity prices, or to provide power during power outages / power interruptions.
[0071] Please see Figure 2 , Figure 2 This is a schematic diagram of the structure of an energy storage system provided in another embodiment of this application, and this application Figure 2 The embodiments are illustrated using a shared energy storage scenario on the generation / distribution side as an example. The energy storage device 100 of this application is not limited to its generation / distribution side energy storage scenario.
[0072] like Figure 2 As shown, the energy storage system 1000 provided in this application embodiment includes an energy storage device 100, a high-voltage cable 210, a first power conversion device 310, and a second power conversion device 410. During power generation, the first power conversion device 310 and the second power conversion device 410 convert other forms of energy into electrical energy, which is then connected to the high-voltage cable 210 and supplied to the power consumption side of the distribution network. When the power load is low and the first power conversion device 310 and the second power conversion device 410 generate excess power, the excess power is stored in the energy storage device 100, reducing wind and solar curtailment rates and improving the absorption of new energy power generation. When the power load is high, the power grid issues an instruction to transmit the power stored in the energy storage device 100 in conjunction with the high-voltage cable 210 in a grid-connected mode to supply power to the power consumption side, providing various services such as peak shaving, frequency regulation, and backup for power grid operation, fully leveraging the peak shaving function of the power grid, promoting peak shaving and valley filling, and alleviating the power supply pressure on the power grid.
[0073] Optionally, the first and second electric energy conversion devices 310 and 410 can convert at least one of solar energy, light energy, wind energy, thermal energy, tidal energy, biomass energy, and mechanical energy into electric energy. In the present application, the number of the energy storage devices 100 can be multiple, and the multiple energy storage devices 100 are connected in series or in parallel with each other, and are supported and electrically connected by an isolation plate (not shown). In the present embodiment, "multiple" means two or more. The energy storage device 100 can also be externally provided with an energy storage box for accommodating the energy storage device 100. Optionally, the energy storage device 100 can include, but is not limited to, a single battery cell, a battery module, a battery pack, a battery system, and the like. The actual application form of the energy storage device 100 provided in the present embodiment can be, but is not limited to, the listed products, and can also be other application forms, and the present embodiment does not strictly limit the application form of the energy storage device 100. The present embodiment only takes the energy storage device 100 as an example of a battery cell for illustration.
[0074] When the energy storage device 100 is a battery cell, the energy storage device 100 can be at least one of a cylindrical battery, a square battery, and the like. In order to more conveniently describe the energy storage device 100 provided in the present embodiment, as an example but not limitation, the energy storage device 100 will be taken as a cylindrical battery in the following detailed description of the technical solutions of the present application.
[0075] Please refer to Figure 3 and Figure 4 The energy storage device 100 provided in the present embodiment includes a shell 11, a bare cell 12, and an end cover plate 13. The shell 11 has an inner cavity 111 and an opening 112 communicating with the inner cavity 111, the bare cell 12 is built in the inner cavity 111, and the end cover plate 13 is sealed at the opening 112 of the shell 11 to seal the bare cell 12 in the inner cavity 111 of the shell 11.
[0076] The shape of the shell 11 can be square (for example, rectangular or square) or circular, and the like.
[0077] When the shape of the shell 11 is circular, the bare cell 12 is usually one; and when the shape of the shell 11 is square, the bare cell 12 can be one or multiple. When the bare cell 12 is multiple, the multiple bare cells 12 can be arranged along the length direction of the shell 11, or can be arranged along the width direction of the shell 11, or can be arranged in an array along the length direction and the width direction of the shell 11. And the multiple bare cells 12 can be connected in series or in parallel, or some of the bare cells 12 are connected in series, and the other bare cells 12 are connected in parallel.
[0078] Please refer to Figure 4 and Figure 5The end cover plate 13 has a first surface 13a and a second surface 13b opposite to each other along the thickness direction of the end cover plate 13. The first surface 13a of the end cover plate 13 faces away from the bare battery cell 12. The end cover plate 13 is provided with a liquid injection hole 131 penetrating through the first surface 13a and the second surface 13b. The liquid injection hole 131 is used to inject electrolyte into the inner cavity 111 of the shell 11, so that the bare battery cell 12 can be soaked in the electrolyte, thereby ensuring the battery performance of the bare battery cell 12.
[0079] Please refer to Figure 4 and Figure 5 The energy storage device 100 further comprises a sealing member 14. The sealing member 14 is arranged at the liquid injection hole 131 to ensure that the bare battery cell 12 can be placed in a sealed space after the liquid injection is completed. In addition, the surface of the sealing member 14 facing away from the bare battery cell 12 is lower than the first surface 13a in the direction from the second surface 13b to the first surface 13a. The surface of the sealing member 14 facing away from the bare battery cell 12 and the hole wall surface of the liquid injection hole 131 form a counterbore 132. That is, the sealing member 14 does not protrude outward from the surface of the battery end cover, thereby avoiding the situation that the sealing member 14 is loosened due to accidental contact, and further affecting the sealing effect of the sealing member 14 on the liquid injection hole 131.
[0080] In some embodiments, as shown in Figure 5 The sealing member 14 comprises a glue pin 141 and a sealing aluminum sheet 142. The glue pin 141 is arranged in the liquid injection hole 131. The sealing aluminum sheet 142 is arranged at the liquid injection hole 131 and is welded with the end cover plate 13. The surface of the sealing aluminum sheet 142 facing away from the bare battery cell 12 is lower than the first surface 13a. The surface of the sealing aluminum sheet 142 facing away from the bare battery cell 12 and the hole wall surface of the liquid injection hole 131 form a counterbore 132. In this way, the glue pin 141 and the sealing aluminum sheet 142 can form double sealing on the liquid injection hole 131, thereby improving the sealing effect of the sealing member 14 on the liquid injection hole 131.
[0081] The material of the glue pin 141 can be silicone, plastic, rubber or foam.
[0082] Please refer to Figure 4 and Figure 5The energy storage device 100 provided by the embodiments of the present application further comprises a cover patch 15 attached to the first surface 13a of the end cover plate 13, and the cover patch 15 is provided with a gas permeable structure 151 communicating with the counterbore 132. Thus, when the energy storage device 100 is heated for thermal shrinkage, the counterbore 132 can exhaust through the gas permeable structure 151, or when the heated energy storage device 100 is naturally cooled or in a low-temperature environment, the counterbore 132 can intake air through the gas permeable structure 151 to achieve the effect of internal and external air pressure balance, thereby avoiding the problem of bulging or depression at the position of the counterbore 132 corresponding to the cover patch 15, ensuring the finished product quality of the energy storage device 100, and further facilitating the improvement of the qualified rate of the energy storage device 100.
[0083] In some embodiments, as shown in Figure 5 and Figure 6 , the gas permeable structure 151 is at least partially arranged corresponding to the counterbore 132, that is, in the thickness direction of the end cover plate 13, the projection of the gas permeable structure 151 on the end cover plate 13 is a first projection, and the projection of the sealing member 14 on the end cover plate 13 is a second projection, the second projection and the first projection at least partially overlap, that is, part of the first projection is covered by the second projection, and the other part is arranged staggered with the second projection and is not covered by the second projection; or, the first projection is completely covered by the second projection.
[0084] In this way, the path for the gas in the counterbore 132 to exhaust out of the counterbore 132, or the path for the external air to enter the counterbore 132, is approximately equal to the thickness of the cover patch 15. Since the thickness of the end cover plate 13 is usually thin, the path for the gas in the counterbore 132 to exhaust out of the counterbore 132, or the path for the external air to enter the counterbore 132, is relatively short, which can quickly achieve the internal and external air pressure balance at the counterbore 132, and effectively avoid the problem of bulging or depression at the position of the counterbore 132 corresponding to the cover patch 15.
[0085] In some embodiments, as shown in Figure 6 and Figure 7 , the gas permeable structure 151 is formed as a slit 151a on the cover patch 15. By arranging the slit 151a, the counterbore 132 can exhaust or intake air through the slit 151a to achieve the effect of internal and external air pressure balance, meeting the demand that the position of the counterbore 132 corresponding to the cover patch 15 can be permeable to air. Since the width of the slit 151a is usually small, it is not easy to be seen by the naked eye, and has little effect on the appearance of the cover patch 15, which can make the cover patch 15 have almost no difference in appearance from the original design, maintaining the original appearance design.
[0086] In some embodiments, as shown in Figure 7As shown, the slit 151a includes a first slit 151a1 and a second slit 151a2, and the first slit 151a1 and the second slit 151a2 are arranged crosswise. That is, a through-type cross incision is made on the cover patch 15, similar to the cross incision for inserting a straw on the lid of a cup of beverage. For example, the shape of the slit 151a can specifically be a "+" shape or an "×" shape.
[0087] By making the slit 151a include the first slit 151a1 and the second slit 151a2 arranged crosswise, the first slit 151a1 and the second slit 151a2 can divide the cover patch 15 into four fan-shaped regions. When heating the energy storage device to achieve the purpose of thermal shrinkage, the gas in the counter bore 132 can lift the fan-shaped regions cut out by the first slit 151a1 and the second slit 151a2 outward, so that the gas in the counter bore 132 can be better released and discharged outward. Or, when the heated energy storage device 100 is naturally cooled or in a low-temperature environment, the gas outside the counter bore 132 can lift the fan-shaped regions cut out by the first slit 151a1 and the second slit 151a2 inward, so that the gas outside the counter bore 132 can better enter into the counter bore 132, realizing the rapid balance of the air pressure inside and outside the counter bore 132, and effectively avoiding the problems of bulging or depression at the position of the cover patch 15 corresponding to the counter bore 132.
[0088] Of course, it can be understood that in other embodiments, the shape of the slit 151a can also be other shapes, such as a "wood" shape, a "*" shape, etc.
[0089] In some embodiments, the length of the slit 151a is 1 mm - 10 mm. Exemplarily, the length of the slit 151a can be 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, or 10 mm, etc. By controlling the length of the slit 151a within the range of 1 mm - 10 mm, the slit 151a can have a certain length, so that when heating the energy storage device 100, the space for the gas in the counter bore 132 to be released outward is larger, and when the heated energy storage device 100 is naturally cooled or in a low-temperature environment, the space for the outside gas to enter into the counter bore 132 is larger, and the air pressure balance inside and outside the counter bore 132 can be better realized; and it can also avoid the length of the slit 151a being too long and affecting the appearance of the cover patch 15.
[0090] In some embodiments, such as Figure 8 and Figure 9As shown, the air permeable structure 151 is formed as a through hole 151b on the cover patch 15. By providing the through hole 151b, the counterbore 132 can exhaust or intake air through the through hole 151b to achieve the effect of balancing the internal and external air pressure, meet the requirement that the cover patch 15 corresponding to the position of the counterbore 132 is air permeable, and the air permeation effect is good; at the same time, since the processing technology of the through hole 151b is relatively simple, it is relatively easy to process and implement in the process, which is beneficial to simplify the processing technology of the cover patch 15.
[0091] Exemplarily, the shape of the through hole 151b can be circular, square (for example, rectangular or square), diamond, triangular, etc.
[0092] When the shape of the through hole 151b is circular, the diameter of the through hole 151b is 1mm-2mm, exemplarily, the diameter of the through hole 151b is 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm or 2mm, etc. By controlling the diameter of the through hole 151b in the range of 1mm-2mm, the through hole 151b can have a certain diameter, so that when the energy storage device 100 is heated, the space for the counterbore 132 to release gas outward is large, and when the heated energy storage device 100 is naturally cooled or in a low-temperature environment, the space for the external gas to enter the gas space in the counterbore 132 is large, which can better achieve the balance of the internal and external air pressure of the counterbore 132; and the diameter of the through hole 151b can be avoided to be too long to affect the appearance of the cover patch 15.
[0093] In some embodiments, as shown in Figure 10 and Figure 11 The energy storage device further comprises a glue layer 16, and the cover patch 15 is bonded to the first surface 13a by the glue layer 16, so that the connection of the cover patch 15 and the end cover plate 13 is more convenient. Wherein, the air permeable structure 151 is formed as an air permeable groove 161 on the glue layer 16.
[0094] An example is shown in Figure 11 The air permeable groove 161 extends from the counterbore 132 to the edge position of the cover patch 15 to form an air permeable opening 162 at the edge position of the cover patch 15, so that the gas in the counterbore 132 can enter the air permeable groove 161 and be discharged to the outside of the counterbore 132 through the air permeable opening 162, or the external gas can enter the air permeable groove through the air permeable opening 162, and then enter the counterbore 132, thereby achieving the balance of the internal and external air pressure of the counterbore 132, and avoiding the problem of bulging or depression of the cover patch 15 corresponding to the position of the counterbore 132.
[0095] In this example, the cover patch 15 needs to be pasted on the top of the heat shrink film to avoid covering and shielding the air permeable opening 162.
[0096] Another example, as shown in Figure 12 , Figure 13 and Figure 14 , the end cover plate 13 is provided with an explosion-proof valve 133 and / or an identification part 134, the cover patch 15 is provided with a window 152 exposing the explosion-proof valve 133 and / or the identification part 134, and the venting groove 161 extends from the sink hole 132 to communicate with the window 152, so that the gas in the sink hole 132 can enter the venting groove 161 and be discharged to the outside of the sink hole 132 through the window 152, or the gas from the outside can enter the venting hole through the window 152, and then enter the sink hole 132, thereby achieving pressure balance between the inside and outside of the sink hole 132, and the cover patch 15 appears bulging or concave at the position corresponding to the sink hole 132.
[0097] In this example, the cover patch 15 can be attached above or below the heat shrink film.
[0098] By providing the venting groove 161 on the adhesive layer 16 on the back of the cover patch 15 to form the venting structure 151, the venting structure 151 cannot be seen in appearance, so that the cover patch 15 has no change in appearance, and the appearance integrity of the energy storage device 100 is maintained, while meeting the demand that the cover patch 15 at the position corresponding to the sink hole 132 can be vented.
[0099] As shown in Figure 12 , when the end cover plate 13 is provided with an explosion-proof valve 133, the window 152 on the cover patch 15 is used to expose the explosion-proof valve 133; as shown in Figure 13 , when the end cover plate 13 is provided with an identification part 134, the window 152 on the cover patch 15 is used to expose the identification part 134; as shown in Figure 14 , when the end cover plate 13 is provided with an explosion-proof valve 133 and an identification part 134, the window 152 on the cover patch 15 can include a first window 152a and a second window 152b, the first window 152a is used to expose the explosion-proof valve 133, and the second window 152b is used to expose the identification part 134, at this time, the sink hole 132 can be located between the first window 152a and the second window 152b, and the venting groove 161 can communicate with the first window 152a or the second window 152b, or the venting groove 161 can include a first venting groove 161a and a second venting groove 161b, the first venting groove 161a can be communicated between the first window 152a and the sink hole 132, and the second venting groove 161b can be communicated between the second window 152b and the sink hole 132.
[0100] Optionally, the identification part 134 can be a two-dimensional code, an identification hole, an identification protrusion, text, a pattern, an icon, or any symbol that can play an identification role.
[0101] In some embodiments, as shown inFigure 14 and Figure 15 As shown in FIG. 16, the length L of the air passage groove 161 in the extending direction of itself is 6mm-24mm; and / or, in the direction perpendicular to the thickness direction of the end cover plate 13 and the extending direction of the air passage groove 161, the width b of the air passage groove 161 is 1mm-5mm; and / or, in the thickness direction of the end cover plate 13, the thickness of the cover plate patch 15 is h0, the depth of the air passage groove 161 is h1, and h1=0.2h0-0.5h0.
[0102] It can be understood that the length L of the air passage groove 161 in the extending direction of itself can be 6mm, 8mm, 10mm, 12mm, 15mm, 17mm, 20mm, 22mm, 23mm or 24mm, etc. By controlling the length L of the air passage groove 161 in the extending direction of itself within the range of 6mm-24mm, it is ensured that the air passage groove 161 can extend to the edge position of the cover plate patch 15 to form the air passage 162, or extend to the window 152 to communicate with the window 152, so as to meet the air passage demand of the cover plate patch 15 at the position corresponding to the counterbore 132.
[0103] It can be understood that the width b of the air passage groove 161 can be 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm or 5mm, etc. By controlling the width b of the air passage groove 161 within the range of 1mm-5mm, on the one hand, the air passage groove 161 can have a certain width, so that when the energy storage device 100 is heated, the space for the counterbore 132 to release gas outward is larger, and when the heated energy storage device 100 is naturally cooled or in a low-temperature environment, the gas space for the external gas to enter the counterbore 132 is larger, so that the air pressure balance inside and outside the counterbore 132 can be better realized; on the other hand, it can ensure that the cover plate patch 15 and the end cover plate 13 have a certain bonding area, so as to ensure the bonding stability between the cover plate patch 15 and the end cover plate 13.
[0104] It can be understood that h1=0.2h0, 0.25h0, 0.3h0, 0.35h0, 0.4h, 0.45h0 or 0.5h0, etc. By controlling the depth of the air passage groove 161 within the range of 20%-50% of the cover plate patch 15, on the one hand, the air passage groove 161 can have a certain depth, so that when the energy storage device 100 is heated, the space for the counterbore 132 to release gas outward is larger, and when the heated energy storage device 100 is naturally cooled or in a low-temperature environment, the gas space for the external gas to enter the counterbore 132 is larger, so that the air pressure balance inside and outside the counterbore 132 can be better realized; on the other hand, it can ensure that the position of the adhesive layer 16 corresponding to the air passage groove 161 has a certain thickness, so as to support the cover plate patch 15 and avoid the problem of depression of the cover plate patch 15 at the position corresponding to the air passage groove 161.
[0105] Any technical features in the above embodiments can be combined, and for the sake of brevity, not all possible combinations are described above, however, as long as the combinations do not conflict with each other, they should be construed to be within the scope of the present disclosure.
[0106] In addition, the above-described embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the patent scope of the present application. It should be pointed out that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the content of the present description should not be understood as a limitation on the present application, and the protection scope of the present application should be subject to the appended claims.
Claims
1. An energy storage device, characterized by, The energy storage device comprises: a housing having an inner cavity and an opening communicating with the inner cavity; a bare cell built in the inner cavity; an end cover plate sealingly arranged at the opening, the end cover plate having first and second surfaces opposite along its thickness direction, the first surface being arranged away from the bare cell, and the end cover plate being provided with a liquid injection hole penetrating through the first and second surfaces; a sealing member sealingly arranged at the liquid injection hole, and in a direction from the second surface to the first surface, the sealing member is lower than the first surface, so that the sealing member and a hole wall surface of the liquid injection hole enclose a counterbore; and a cover plate patch attached to the first surface and covering the counterbore, and the cover plate patch being provided with a gas permeable structure communicating with the counterbore.
2. The energy storage device of claim 1, wherein, In the thickness direction of the end cover plate, a projection of the gas permeable structure on the end cover plate is a first projection, and a projection of the sealing member on the end cover plate is a second projection, the second projection and the first projection at least partially overlap.
3. The energy storage device of claim 2, wherein, The gas permeable structure is formed as a slit on the cover plate patch.
4. The energy storage device of claim 3, wherein, The slit includes a first slit and a second slit, and the first slit and the second slit are arranged in cross.
5. The energy storage device of claim 3, wherein, The length of the slit is 1mm-10mm.
6. The energy storage device of claim 2, wherein, The gas permeable structure is formed as a through hole on the cover plate patch.
7. The energy storage device of claim 6, wherein, The shape of the through hole is circular, and the diameter of the through hole is 1mm-2mm.
8. The energy storage device of claim 1, wherein, The energy storage device further comprises a glue layer, the cover plate patch is attached to the first surface through the glue layer, and the gas permeable structure is formed as a gas permeable groove on the glue layer. The gas permeable groove extends from the counterbore to an edge position of the cover plate patch to form a gas permeable opening at the edge position of the cover plate patch. Alternatively, The end cover plate is provided with an explosion-proof valve and / or an identification part, the cover plate patch is provided with a window exposing the explosion-proof valve and / or the identification part, and the gas permeable groove extends from the counterbore to communicate with the window.
9. The energy storage device of claim 8, wherein, The length of the gas permeable groove in its extension direction is 6mm-24mm; and / or, In a direction perpendicular to the thickness direction of the end cover plate and the extension direction of the gas permeable groove, the width of the gas permeable groove is 1mm-5mm; and / or, In the thickness direction of the end cover plate, the thickness of the cover plate patch is h0, and the depth of the gas permeable groove is h1, h1=0.2h0-0.5h0.
10. An energy storage system characterized by, The energy storage system has the energy storage device as claimed in any one of claims 1-9.