Battery cover plate and single battery

Abstract

The utility model provides a battery cover plate and a single battery, and mainly solves the problems of low assembly efficiency and low yield of a large-capacity battery due to the fact that the single battery needs to be unpacked twice in the assembly process of the existing large-capacity battery. The battery cover plate comprises a cover plate body, an unpacking piece and a reinforcing piece, a weak area is arranged on the cover plate body; the unpacking piece comprises a U-shaped connecting piece and two strip-shaped plates. The U-shaped connecting piece comprises a middle bottom plate and two vertical plates fixed to the two sides of the middle bottom plate. A middle bottom plate of the U-shaped connecting piece is fixed to a weak area of the cover plate body, the two strip-shaped plates are fixedly connected with vertical plates of the U-shaped connecting piece respectively, and unpacking gaps are formed between the strip-shaped plates and the cover plate body. The reinforcing piece is fixed on the end face of the middle bottom plate away from the cover plate body; under the action of external force, the unpacking piece, the reinforcing piece and the weak area are separated from the cover plate body, so that the battery cover plate forms an opening.

Description

Technical Field

[0001] The utility model relates to the field of batteries, and particularly relates to a battery cover plate and a single battery. Background Art

[0002] In recent years, with the further development of lithium-ion batteries, the application scenarios of lithium-ion batteries have become more and more extensive, especially in some scenarios with relatively high requirements for battery capacity. For example: power batteries for automobiles, energy storage batteries for household photovoltaic energy storage integrated machines, and batteries for power plant energy storage systems, etc.

[0003] In the above application scenarios, in order to meet the relatively high capacity requirements, the existing method is to connect multiple single batteries together in a series-parallel combination to form a large-capacity battery. However, due to the differences among the single batteries in the above large-capacity battery, the uniformity of the single batteries in the large-capacity battery is poor, which will directly limit the capacity and cycle life of the large-capacity battery.

[0004] To solve the above problems, in the existing large-capacity battery, the electrolyte areas and gas areas of each single battery are connected, so that each single battery is in a unified shared electrolyte and gas system, which reduces the differences among the single batteries to a certain extent and improves the cycle life of the large-capacity battery.

[0005] In the production process of the above large-capacity battery, first, a first opening is made on the battery housing of each finished single battery, and then a sealing mechanism is installed on the first opening. The main function of the sealing mechanism is to seal the single battery and protect the electrolyte in the single battery from contacting the air. When each single battery is assembled into a large-capacity battery, the above sealing mechanism is detached from the single battery, and at this time, a second opening is formed on the battery housing. Finally, the inner cavities of each single battery are connected through the second opening. The above unpacking method requires unpacking the single battery twice, making the production process of the large-capacity battery cumbersome and the assembly efficiency low. Summary of the Invention

[0006] To solve the problems that in the assembly process of the existing large-capacity battery, the single battery needs to be unpacked twice, resulting in low assembly efficiency and low yield of the large-capacity battery, the utility model provides a battery cover plate and a single battery.

[0007] To solve the above problems, the technical solution of the utility model is as follows:

[0008] A battery cover plate, comprising a cover plate body, an opening member and a reinforcing member; a weak area is provided on the cover plate body; the opening member includes a U-shaped connecting piece and two strip plates, and the U-shaped connecting piece includes a middle bottom plate and two vertical plates respectively fixed on both sides of the middle bottom plate; the middle bottom plate of the U-shaped connecting piece is connected to the weak area of the cover plate body, and the two strip plates are respectively fixedly connected to the vertical plates of the U-shaped connecting piece to form flanges on both sides of the U-shaped connecting piece, so that an opening gap is formed between the strip plates and the cover plate body; the reinforcing member is fixed on the end face of the middle bottom plate away from the cover plate body; under the action of an external force, the opening member, the reinforcing member and the weak area are separated from the cover plate body to form an opening in the battery cover plate.

[0009] Further, the reinforcing member has the same shape and size as the opening member, and the installation directions of the reinforcing member and the opening member are perpendicular.

[0010] Further, the reinforcing member has the same shape as the opening member, the length of the reinforcing member is less than the length of the opening member, and the installation directions of the reinforcing member and the opening member are perpendicular.

[0011] Further, the reinforcing member includes at least one flat plate, and the size of the flat plate is the same as the size of the middle bottom plate.

[0012] Further, both the opening member and the reinforcing member are integrally extruded molding parts.

[0013] Further, the opening member is welded to the weak area of the cover plate body, and the reinforcing member is welded to the middle bottom plate of the U-shaped connecting piece.

[0014] Further, a circular groove is provided on the cover plate body, the area enclosed by the circular groove is the weak area, and the cross section of the circular groove is U-shaped or V-shaped.

[0015] The present invention also provides a single cell, which includes a cell housing, and the cell housing includes an upper cover plate, a lower cover plate and a cylinder, and at least one of the upper cover plate and the lower cover plate adopts the above-mentioned battery cover plate.

[0016] Further, a through groove or a through hole for fixing a heat transfer tube is provided on the polar terminal of the single cell.

[0017] Compared with the prior art, the beneficial effects of the technical solution of the present invention are as follows:

[0018] 1. The present utility model is provided with a weak area on the cover plate body, and an opening member and a reinforcement member are connected to the weak area; under the action of an external force, the opening member, the reinforcement member and the weak area are separated from the cover plate body, so that an opening is formed in the battery cover plate. When each single battery forms a large-capacity battery, only one opening is required for the single battery. Compared with the existing method that requires two openings when single batteries form a large-capacity battery, the reduction in the number of openings improves the production efficiency of the large-capacity battery, and also minimizes the probability of opening operation errors, thereby improving the yield of the large-capacity battery.

[0019] At the same time, when the opening member is separated from the cover plate body at the weak area, the reinforcement member not only enhances the overall stiffness of the opening member, but also enables the opening member to be secondarily connected to the weak area, improving the connection strength between the opening member and the weak area. As a result, the opening member and the weak area can be quickly, accurately and reliably separated from the cover plate body to form an effective opening.

[0020] 2. In the battery cover plate of the present utility model, the reinforcement member has the same shape and size as the opening member, so that the reinforcement member and the opening member have the same structure, reducing the processing and manufacturing costs.

[0021] 3. In the battery cover plate of the present utility model, the reinforcement member includes at least one flat plate, and the size of the flat plate is the same as that of the middle bottom plate. The reinforcement member with such a structure is simple in structure and convenient to manufacture.

[0022] 4. In the battery cover plate of the present utility model, both the opening member and the reinforcement member are integrally extruded forming parts. Compared with the method of separately processing and then fixedly connecting, the one-piece processing and forming is not only convenient for processing, reduces costs, but also can improve the strength of the entire opening member.

[0023] 5. In the battery cover plate of the present utility model, the method of forming the weak area on the cover plate body through an annular groove is more convenient for processing and manufacturing and has a lower manufacturing cost compared to using different thicknesses or other forms.

[0024] 6. The battery cover plate of the single battery of the present utility model is provided with an opening member. When using this single battery to form a large-capacity battery, the step of opening the finished single battery once is omitted, avoiding the problem of low yield caused by the transformation of the battery due to the first opening. In addition, compared with the existing method that requires two openings when finished single batteries form a large-capacity battery, the reduction in the number of openings improves the production efficiency of the large-capacity battery, and also minimizes the probability of opening operation errors, thereby improving the yield of the large-capacity battery.

[0025] 7. The polar terminal of the single battery of the present utility model is provided with a through groove or a through hole for fixing the heat transfer tube. The large-capacity battery formed can reduce the temperature of the polar terminal where the heat is most concentrated on each single battery through the heat transfer tube, which can further improve the safety of the operation of the large-capacity battery.

[0026] Other advantages, objectives and features of the present utility model will be partially reflected by the following description and partially understood by those skilled in the art through the research and practice of the present utility model. Brief Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0028] Figure 1 Structural schematic diagram of the lower cover plate with an unpacking part and a reinforcing part in Embodiment 1;

[0029] Figure 2 Explosion schematic diagram of the lower cover plate with an unpacking part and a reinforcing part in Embodiment 1;

[0030] Figure 3 Structural schematic diagram of the unpacking part in Embodiment 1;

[0031] Figure 4 Schematic diagram of the through groove provided on the polar terminal of the single battery in Embodiment 2;

[0032] Figure 5 Structural schematic diagram of the large-capacity battery in the embodiment;

[0033] Figure 6 Structural schematic diagram of the large-capacity battery in the embodiment;

[0034] Figure 7 Structural schematic diagram of the unpacking device in the embodiment;

[0035] Figure 8 Partial enlarged schematic diagram of the unpacking device in the embodiment.

[0036] The reference numerals are: 1 - single cell, 2 - unpacking member, 3 - reinforcing member, 4 - unpacking device, 5 - outer shell, 6 - hollow member, 11 - upper cover plate, 12 - cylinder body, 13 - lower cover plate, 14 - cover plate body, 141 - weak area, 15 - polar terminal, 16 - through groove, 21 - U-shaped connecting piece, 211 - intermediate bottom plate, 212 - vertical plate, 22 - strip plate, 41 - push rod, 42 - unpacking block, 43 - penetrating rod, 411 - flat plate, 412 - side plate, 421 - first wedge surface, 422 - second wedge surface, 51 - electrolyte sharing chamber, 52 - gas sharing chamber, 53 - operation port, 61 - operation port. Detailed implementation manners

[0037] To make the above objects, features and advantages of the present utility model more obvious and understandable, the following detailed description of the specific implementation manners of the present utility model is provided in conjunction with the accompanying drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present utility model, rather than all of them. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0038] "In other embodiments" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment that mutually excludes other embodiments. In this specification, unless otherwise clearly defined and limited, the term "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, indirectly connected through an intermediate member, or the internal communication of two elements. For those of ordinary skill in the art, the specific meanings of the above terms in this specification can be understood according to specific circumstances.

[0039] Meanwhile, in the description of the present utility model, it should be noted that the orientation or positional relationship indicated by terms such as "top and bottom" is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present utility model. In addition, the terms "first, second or third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0040] The utility model is provided with a weak area on the cover plate body, and an opening member and a reinforcing member are connected to the weak area; under the action of an external force, the opening member, the reinforcing member and the weak area are separated from the cover plate body, so that an opening is formed in the battery cover plate. This method does not require an opening to be formed on the battery cover plate and then the opening member to be installed. When each single battery forms a large-capacity battery, only one opening is needed. Compared with the method of opening twice, the reduction of the opening times can not only avoid the influence of external air on each single battery as much as possible, thereby improving the yield of the large-capacity battery, but also the method of opening once improves the assembly efficiency of the large-capacity battery.

[0041] In addition, an opening member is connected to the weak area of the cover plate body. When opening the single battery, the opening member and the weak area are integrally separated from the cover plate body, and no remaining part will stay in the single battery to cause influence.

[0042] Embodiment 1

[0043] As Figure 1 and Figure 2 shown, this embodiment provides a battery cover plate, which includes a cover plate body 14, an opening member 2 and a reinforcing member 3; a weak area 141 is provided on the cover plate body 14; the opening member 2 is fixed on the weak area 141, and the reinforcing member 3 is fixed on the opening member 2. Under the action of an external force, the opening member 2, the reinforcing member 3 and the weak area 141 are separated from the cover plate body 14, so that an opening is formed in the battery cover plate.

[0044] In this embodiment, an opening member 2 is provided on the cover plate body 14. The opening member 2 and the weak area 141 are separated from the cover plate body 14 under the action of an opening device to form an opening. During the actual opening operation, due to the setting of the weak area 141 or the insufficient strength of the opening member 2, the opening member 2 is bent during the opening process, or after being separated from the weak area 141, no effective opening is formed. At this time, in this embodiment, a reinforcing member 3 is installed on the opening member 2, and the reinforcing member 3 is fixed on the part where the opening member 2 is connected to the weak area 141 (i.e., the middle bottom plate). The reinforcing member 3 not only enhances the overall stiffness of the opening member 2, but also enables the opening member 2 to be secondarily connected to the weak area 141, improving the connection strength between the opening member 2 and the weak area 141, and further enabling the opening member 2 and the weak area 141 to be quickly, accurately and reliably separated from the cover plate body 14 to form an effective opening.

[0045] The weak area 141 on the cover plate body 14 in this embodiment can be realized in various ways;

[0046] First, the wall thickness of the upper part of the cover body 14 is smaller than that of other areas, and the area with smaller wall thickness is the weak area 141; during specific processing, the weak area 141 is formed by stamping or milling, and its thickness is smaller than the thickness of the rest of the battery shell; for example, when the thickness of the weak area 141 is 0.5 mm, the thickness of the rest of the cover body 14 is 1.5 mm;

[0047] Second, part of the side wall of the cover body 14 is sunken inwards or convex outwards to form a weak area 141;

[0048] Third, a circle of annular grooves is disposed on the cover body 14 , and the area circled by the annular grooves is the weak area 141 .

[0049] In this embodiment, the preferred formation method of the weak area 141 is: a circle of annular grooves is provided on the cover body 14, and the area enclosed by the annular grooves is the weak area 141. At the same time, the shape of the above weak area 141 is as easy to tear and easy to form an opening as possible, such as a teardrop shape, a circle or a runway shape. The cross section of the annular groove forming the above weak area 141 is preferably U-shaped or V-shaped. The U-shaped or V-shaped annular groove is easy to process and easy to tear to form an opening, which reduces the operating force when opening the package.

[0050] like Figure 3 As shown, the packaging opening piece 2 in this embodiment is similar to a component of an inverted "J"-shaped structure, mainly including a U-shaped connecting piece 21 and two strip plates. The U-shaped connecting piece 21 is specifically a sheet structure with a U-shaped cross-section, which includes a middle bottom plate 211 and two vertical plates 212 respectively fixed on both sides of the middle bottom plate 211. The middle bottom plate 211 of the U-shaped connecting piece 21 is fixed to the weak area 141 of the cover body 14. There are two strip plates, which are respectively fixedly connected to the vertical plates 212 of the U-shaped connecting piece 21 to form flanges on both sides of the U-shaped connecting piece, so that an opening gap is formed between the strip plate and the cover body 14. The strip plate is mainly used to cooperate with the opening device 4 to transfer the force of the opening device 4 to the U-shaped connecting piece 21, thereby separating the packaging opening piece 2 from the cover body 14 to form an opening on the cover body 14.

[0051] The reinforcing member 3 in this embodiment is fixed on the end surface of the middle bottom plate 211 away from the cover plate body 14, which not only improves the overall rigidity of the opening piece 2, but also enables the opening piece 2 to be connected to the weak area 141 for a second time, which can be mainly realized by the following structure:

[0052] First, the reinforcement member 3 includes at least one flat plate. Each flat plate is stacked on the intermediate bottom plate 211 and fixedly connected to the intermediate bottom plate 211. The size of the flat plate is less than or equal to the size of the intermediate bottom plate 211 of the unpacking member 2. Preferably, the size of the flat plate is the same as the size of the intermediate bottom plate 211. The reinforcement member with this structure is simple in structure and convenient to manufacture.

[0053] Second, the reinforcement member 3 has the same shape as the unpacking member 2, that is, the cross-sectional shape of the reinforcement member 3 is the same as that of the unpacking member 2. The length of the reinforcement member 3 is less than the length of the unpacking member 2. When connecting, the intermediate bottom plate of the reinforcement member 3 is fixedly connected to the intermediate bottom plate 211 of the unpacking member 2, and the installation direction of the reinforcement member 3 is perpendicular to that of the unpacking member 2.

[0054] Third, the reinforcement member 3 has the same shape and size as the unpacking member 2, that is, the cross-sectional shape of the reinforcement member 3 is the same as that of the unpacking member 2. The length of the reinforcement member 3 is the same as the length of the unpacking member 2. When connecting, the intermediate bottom plate of the reinforcement member 3 is fixedly connected to the intermediate bottom plate 211 of the unpacking member 2, and the installation direction of the reinforcement member 3 is perpendicular to that of the unpacking member 2.

[0055] The reinforcement member 3 in the second structure and the third structure has the same structure as the unpacking member 2. The reinforcement member 3 and the unpacking member 2 have the same structure, which reduces the processing and manufacturing costs of the two, so that the processing and manufacturing can be realized by using the same mold or extrusion device. Compared with the installation of the reinforcement member 3 in the third structure, after installation, part of the reinforcement member 3 protrudes from the intermediate bottom plate of the unpacking member 2. The reinforcement member 3 in the third structure can be completely arranged on the intermediate bottom plate of the unpacking member 2, which is relatively more beautiful.

[0056] When the unpacking member 2 and the reinforcement member 3 in this embodiment are specifically processed and manufactured, the strip plate and the U-shaped connecting piece 21 can be processed separately and then fixed by welding or other means, or the strip plate and the U-shaped connecting piece 21 can be integrally processed directly. Specifically, it can be formed by one-time extrusion using an extruder, or the entire metal plate can be bent using a bending machine, or it can be formed by casting in one step. Compared with the method of fixing and connecting after separate processing, the integrally processed and formed method is not only convenient for processing, reduces costs, but also can improve the strength of the entire unpacking member 2.

[0057] In this embodiment, when each component is installed, a weak area 141 can be first formed on the cover plate body 14, the unpacking member 2 is fixed on the weak area 141 of the cover plate body 14, and then the reinforcing member 3 is fixed on the middle bottom plate 211 of the unpacking member 2. During specific connection, the U-shaped connecting piece 21 and the weak area 141 of the cover plate body 14 can be specifically fixed by welding or bonding, and the reinforcing member 3 and the middle bottom plate 211 of the unpacking member 2 can be specifically connected by welding, bonding or screw fixing. Preferably, the unpacking member 2 is welded on the weak area 141 of the cover plate body 14, and the reinforcing member 3 is welded on the middle bottom plate 211 of the U-shaped connecting piece 21. After being fixed by welding, the connection between the unpacking member 2 and the reinforcing member 3 is relatively reliable, and it is easy to form an opening on the battery cover plate.

[0058] Embodiment 2

[0059] As Figure 1 、 Figure 2 shown, this embodiment provides a single cell, and the single cell 1 includes a battery housing and an electrode assembly disposed in the battery housing. The battery housing includes an upper cover plate 11, a lower cover plate 13 and a cylinder 12. At least one of the upper cover plate 11 and the lower cover plate 13 adopts the battery cover plate in Embodiment 1. A polarity terminal for leading out the current of the single cell 1 is provided on the upper cover plate 11, and the polarity terminal includes a positive polarity terminal and a negative polarity terminal. An unpacking member 2 and a reinforcing member 3 are provided on the battery cover plate. When each single cell 1 forms a large-capacity battery, under an external force, the unpacking member 2, the reinforcing member 3 and the weak area 141 are integrally separated from the battery cover plate to form an opening on the battery cover plate, so that the electrolytes and gases of each single cell 1 communicate with each other.

[0060] In other embodiments, the weak area can also be provided on the cylinder 12 of the single cell 1. At this time, the unpacking member 2 and the reinforcing member 3 are connected to the weak area of the cylinder 12. When each single cell 1 forms a large-capacity battery, under an external force, the unpacking member 2, the reinforcing member 3 and the weak area 141 are integrally separated from the cylinder 12 to form an opening on the cylinder 12, so that the electrolytes and gases of each single cell 1 communicate with each other.

[0061] Fixing the unpacking member 2 on the weak area of the battery housing eliminates the need to form an opening on the battery housing before installing the unpacking member 2. When each single cell 1 forms a large-capacity battery, only one unpacking is required. Compared with the method of unpacking twice, the reduction in the number of unpacking operations can not only minimize the impact of external air on each single cell 11, thereby improving the yield of the large-capacity battery, but also the method of one-time unpacking improves the assembly efficiency of the large-capacity battery.

[0062] This embodiment can also perform the following structural optimizations on the single cell 1 having the unpacking member 2 and the reinforcing member 3.

[0063] As Figure 4As shown in the figure, a through groove 16 or a through hole for fixing a heat transfer tube is provided on the polar terminal 15 of the single cell 1. When multiple single cells 1 are assembled into a large-capacity battery, the temperature of each single cell can be transferred from the polar terminal 15 to an external temperature control device through the heat transfer tube, reducing the problem that the overheating of the single cell 1 affects the performance of the large-capacity battery. More importantly, the direct temperature control of each single cell 1 reduces the probability of thermal runaway, thereby improving the safety.

[0064] When specifically setting, compared with the through hole, the through groove 16 is more convenient for on-site installation and has relatively low requirements for installation. In this embodiment, the polar terminal 15 of the single cell 1 is a cylinder. At this time, the through groove 16 can be provided on the side wall or end face of the cylinder.

[0065] As Figure 5 shown in the figure, the above single cells can form a large-capacity battery with the following structure. The large-capacity battery includes a housing 5 and multiple single cells 1. The single cell 1 specifically adopts the single cell 1 in Embodiment 2. The number of single cells 1 can be adjusted according to actual needs. The inner cavity of each single cell 1 includes an electrolyte area and a gas area. Multiple single cells 1 are arranged in the same direction and placed in the housing 5. The housing 5 is provided with a shared chamber, and the inner cavity of the shared chamber is communicated with the inner cavities of all single cells 1.

[0066] As Figure 5 shown in the figure, after multiple single cells 1 are arranged in the same direction and placed in the housing 5, avoidance holes are provided on the top plate of the housing 5 corresponding to the polar terminals 15 of each single cell 1. The polar terminals 15 of each single cell 1 extend out of the corresponding avoidance holes as the polar terminals of the large-capacity battery (the polar terminals 15 of all single cells 1 on one side are used as the positive polar terminals of the large-capacity battery, and the polar terminals 15 of all single cells 1 on the other side are used as the negative polar terminals of the large-capacity battery). The area of the top plate of the housing 5 corresponding to the avoidance holes is fixedly sealed with the housing of the single cell 1, so that the gap between the polar terminal 15 and the avoidance hole is sealed.

[0067] It should be noted that the polar terminal 15 of the single cell 1 here can be the pole column of the single cell 1. If it is necessary to avoid that the pole column of the single cell 1 cannot smoothly extend out of the avoidance hole as the polar terminal, a pole column adapter can also be connected to the pole column of the single cell 1, and the overall structure of the cooperation between the pole column of the single cell 1 and the pole column adapter is used as the polar terminal 15 of the single cell 1.

[0068] The shared chamber within the above-mentioned outer shell 5 can be an electrolyte shared chamber 51. The electrolyte shared chamber 51 is a liquid channel provided on the bottom plate of the outer shell 5. The inner cavity of the electrolyte shared chamber 51 is connected to the electrolyte regions in the inner cavities of all the single cells 1. Through the electrolyte shared chamber 51, each single cell 1 can be in a unified electrolyte environment, ensuring the uniformity of the electrolyte in each single cell 1 and enhancing the performance and charge-discharge cycle life of the large-capacity battery 1.

[0069] The shared chamber within the above-mentioned outer shell 5 can be a gas shared chamber 52. The gas shared chamber 52 is a gas channel provided on the top plate of the outer shell 5. The inner cavity of the gas shared chamber 52 is connected to the gas regions in the inner cavities of all the single cells 1. Through the gas shared chamber 52, gas balance of each single cell 1 can be achieved, and the performance and charge-discharge cycle life of the large-capacity battery 1 can also be enhanced.

[0070] The above-mentioned shared chamber can be a gas-liquid shared chamber. The inner cavity of the gas-liquid shared chamber is connected to both the electrolyte region and the gas region in the inner cavities of all the single cells 1. Through one gas-liquid shared chamber, each single cell 1 can be in a unified electrolyte environment and gas environment, enhancing the performance and charge-discharge cycle life of the large-capacity battery. Specifically, when setting, a protrusion extending along the arrangement direction of the single cells 1 is provided on the side wall of the outer shell 5, and a gas-liquid shared chamber is formed at the protrusion part. The gas-liquid shared chamber is connected to both the electrolyte region and the gas region of each single cell 1.

[0071] The above-mentioned shared chamber can also simultaneously include an electrolyte shared chamber 51 and a gas shared chamber 52. The inner cavity of the electrolyte shared chamber 51 is connected to the electrolyte regions in the inner cavities of all the single cells 1, and the inner cavity of the gas shared chamber 52 is connected to the gas regions in the inner cavities of all the single cells 1. Placing multiple single cells 1 inside an outer shell having an electrolyte shared chamber 51 and a gas shared chamber 52 enables the sharing of electrolyte and gas of each single cell 1 to ensure the consistency of each single cell 1, making the electrolyte and gas of all single cells 1 in the same system, reducing the differences between each single cell 1, and to a certain extent enhancing the consistency between each single cell 1, thereby to a certain extent enhancing the cycle life of the large-capacity battery.

[0072] The above-mentioned shared chamber may also include an electrolyte shared chamber 51 and a gas shared chamber 52 at the same time. The inner cavity of the electrolyte shared chamber 51 communicates with the electrolyte regions in the inner cavities of all the single cells 1. The gas shared chamber 52 is a gas passage located between the top plate of the outer shell 5 and each single cell 1. This gas passage covers the explosion vent part (specifically, it can be an explosion vent film) of each single cell 1. When the explosion vent part of any single cell 1 is broken through by the hot runaway flue gas in the inner cavity, the gas region in the inner cavity of this single cell 1 communicates with the gas passage. At this time, the gas shared chamber 52 is used as an explosion vent passage. That is, during the normal operation of the large-capacity battery, the inner cavities of each single cell 1 do not communicate with the gas passage. When any single cell 1 has a thermal runaway, when the explosion vent part at the top of this single cell 1 is opened by the flue gas in the inner cavity, the inner cavity of this single cell 1 communicates with the gas passage, and the hot runaway flue gas is discharged through the gas passage, improving the safety of the large-capacity battery.

[0073] As Figure 5 shown, an operation port 53 is provided on the above-mentioned outer shell 5. Through this operation port 53, the unpacking device can perform unpacking operations on each single cell 1 inside the outer shell. After unpacking each single cell 1, this operation port can also inject electrolyte into the inner cavities of each single cell 1 and the shared chamber, for liquid injection, liquid replenishment or liquid replacement of the large-capacity battery. After unpacking or liquid injection is completed, the operation port 53 needs to be sealed with a plug or a valve. Alternatively, an explosion vent component can also be installed on the operation port 53 to perform explosion venting on the large-capacity battery, improving the safety of the large-capacity battery.

[0074] In the large-capacity battery of this embodiment, heat transfer tubes are provided on the polar terminals 15 of each single cell 1. The heat transfer tubes are fixed in the through grooves 16 or through holes on the polar terminals 15 of each single cell 1, and the heat transfer tubes are insulated from the polar terminals of each single cell 1. The heat transfer tubes process the heat at the top of the large-capacity battery, enabling the large-capacity battery to work safely and reliably, and avoiding performance problems and safety problems caused by too high or too low temperature of the large-capacity battery.

[0075] As Figure 6 shown, the above-mentioned single cells can also form a large-capacity battery with the following structure. This large-capacity battery includes a plurality of single cells 1 and a hollow member 6. The number of single cells 1 can be adjusted according to actual capacity requirements. The plurality of single cells are arranged in sequence. The hollow member 6 is a split structure, mainly composed of a hollow box body with one end open and a cover plate for covering the opening. The hollow box body is fixed on the upper cover plate 11 or the lower cover plate 13 of each single cell 1. A plurality of through holes are opened on the side wall of the hollow member 6 that cooperates with each single cell 1. The unpacking parts 2 of each single cell 1 pass through the through holes and are located inside the hollow member 6. When the unpacking part 2 is separated from the single cell 1, the inner cavities of each single cell 1 communicate with the inner cavity of the hollow member 6, so that each single cell 1 is in the same electrolyte system and gas balance system.

[0076] The quantity and installation position of the above-mentioned hollow member 6 are determined according to the functional system required by the large-capacity battery. When a shared electrolyte system needs to be provided, that is, when the electrolytes between the individual cells 1 communicate with each other, one hollow member 6 is fixedly connected to the lower cover plate 13 of each individual cell 1; when a gas balance system needs to be provided, that is, when the gases between the individual cells 1 communicate with each other, one hollow member 6 is fixedly connected to the upper cover plate 11 of each individual cell 1; when both a shared electrolyte system and a gas balance system need to be provided, that is, when both the electrolyte area and the gas area between the individual cells 1 communicate with each other, two hollow members 6 are used, one of which is fixedly connected to the upper cover plate 11 of the individual cell 1, and the other hollow member 6 is connected to the lower cover plate 13 of the individual cell 1;

[0077] An operation port 61 is provided on the above-mentioned hollow member 6. Through this operation port 61, the unpacking device can perform an unpacking operation on each individual cell 1. After unpacking each individual cell 1, the operation port can also inject electrolyte into the inner cavity of each individual cell 1 and the shared cavity, for liquid injection, liquid supplement or liquid replacement of the large-capacity battery. After unpacking or liquid injection is completed, the operation port 61 needs to be sealed with a plug or a valve. Alternatively, an explosion relief component can also be installed on the operation port 61 to perform explosion relief on the large-capacity battery, improving the safety of the large-capacity battery.

[0078] In the large-capacity battery of this embodiment, heat transfer tubes are provided on the polar terminals 15 of each individual cell 1. The heat transfer tubes are fixed in the through slots 16 or through holes of the polar terminals 15 of each individual cell 1, and insulation is maintained between the heat transfer tubes and the polar terminals of each individual cell 1. The heat transfer tubes process the heat at the top of the large-capacity battery, enabling the large-capacity battery to work safely and reliably, and avoiding performance problems and safety problems caused by too high or too low temperature of the large-capacity battery.

[0079] During the manufacturing process of the above-mentioned large-capacity battery, the unpacking device 4 detaches each unpacking part 2 from each individual cell 1, forms an opening on the individual cell 1, and completes the unpacking operation of each individual cell 1, thereby enabling gas sharing, electrolyte sharing, or both gas and electrolyte sharing among the individual cells 1 in the large-capacity battery.

[0080] The structure of the unpacking device for performing an unpacking operation on each individual cell 1 of the above-mentioned large-capacity battery is as follows:

[0081] As Figure 7 and Figure 8As shown in the figure, the above-mentioned unpacking device 4 includes a push rod 41 and two unpacking blocks 42. The push rod 41 is a long strip rod, and its length is adapted to the length after the arrangement of each single battery 1. At the same time, the cross-section of the push rod 41 is U-shaped, mainly composed of a flat plate 411 and side plates 412 on both sides of the flat plate 411. The width between the two side plates 412 is greater than the distance between the two strip plates of the unpacking member 2 on the battery cover plate, and the height of the side plate 412 is greater than the distance between the strip plate and the cover body 14. For the convenience of describing the structure of the entire unpacking device 4, the two ends of the push rod 41 are respectively set as the unpacking end and the operation end. The unpacking end is the end extending into the housing to unpack the single battery 1, and the operation end is the end outside the housing.

[0082] The above-mentioned two unpacking blocks 42 are both wedge-shaped blocks, which are respectively fixed on the inner sides of the two side plates 412, and the clearance value between the wedge-shaped block and the flat plate 411 is greater than the thickness of the strip plate. The wedge-shaped block has a first wedge surface 421 extending along its thickness direction. The first wedge surface 421 cooperates with the strip plate of the unpacking member 2 to separate the unpacking member 2 of each single battery 1 from the cover body 14, so that the cover body 14 forms an opening. At this time, the minimum thickness of the wedge-shaped block <H < the maximum thickness of the wedge-shaped block, where H is the distance between the strip plate of the unpacking member 2 and the cover body 14. That is to say, the thickness of the side of the wedge-shaped block close to the unpacking end is less than the thickness of the side far from the unpacking end, forming the first wedge surface 421. When the push rod 41 slides, the first wedge surface 421 cooperates with the strip plate of the unpacking member 2 to separate the unpacking member 2 from the cover body 14 as a whole. At the same time, the wedge-shaped block has a second wedge surface 422 along its width direction. The second wedge surfaces 422 of the two wedge-shaped blocks are arranged oppositely, and the second wedge surface 422 is perpendicular to the first wedge surface 421. The extension trend of the second wedge surface 422 is the same as that of the first wedge surface 421. Its main function is to generate a guiding effect when the unpacking block 42 cooperates with the strip plate, so that the unpacking block 42 can accurately and quickly insert into the space between the strip plate and the cover body 14, avoiding the process of having to move left and right multiple times to align when the push rod 41 cooperates with the strip plate of the unpacking member 2.

[0083] After the unpacking device 4 separates the unpacking piece 2 of each single battery 1 from the cover plate body 14, it is necessary to take out the unpacking piece 2 and the unpacking device 4, remove the unpacking piece 2 from the unpacking device 4, and then perform the unpacking of the next single battery 1. In this process, the push rod 41 needs to repeatedly enter and exit the outer shell. Based on this, in this embodiment, two through rods 43 are added inside the two side plates 412. The through rods 43 are located on the side of the wedge block away from the unpacking end, and there is a gap between the through rods 43 and the flat plate 411. After the unpacking piece 2 of each single battery 1 is separated from the cover plate body 14, the unpacking piece 2 can be sleeved on the through rod 43. The through rod 43 collects the unpacking pieces 2 separated from the cover plate body 14 on each single battery 1, omitting the process of removing the unpacking piece 2, and thus the unpacking operation of the next single battery 1 can be continuously performed, improving the unpacking efficiency.

[0084] The following describes the unpacking process of each single battery 1 when each single battery 1 is arranged in the outer shell 5. This unpacking process is carried out in a set environment. Usually, the set environment is preferably an environment with a dew point standard between -25°C and -40°C, a temperature of 23°C ± 2°C, and a cleanliness of 100,000 levels. The specific process is as follows:

[0085] S1. Flip the entire large-capacity battery as a whole. At this time, the polar terminals of each single battery 1 are at the bottom, and the lower cover plate 13 of each single battery 1 is at the top. Subsequently, remove the explosion vent component, the plugging piece or the valve on the operation port 53 of the outer shell 5.

[0086] S2. Insert the push rod 41 from the operation port. The push rod 41 slides along the arrangement direction of each single battery 1 and slides above the unpacking piece 2 of the first single battery 1. At this time, the unpacking block 42 gradually moves forward synchronously and slides below the strip plates on both sides of the U-shaped connecting piece 21 until the first wedge surface 421 contacts the top of the strip plate. Since the maximum thickness of the wedge block is greater than the distance between the strip plate and the cover plate body 14, when the push rod 41 continues to slide, under the action of the push rod 41, the first wedge surface 421 of the unpacking block 42 jacks up the strip plates on both sides of the U-shaped connecting piece 21. At this time, the strip plates drive the entire U-shaped connecting piece 21 to separate from the cover plate body 14, and the entire unpacking piece 2 and the weak area 141 are separated from the lower cover plate 13 of the single battery 1, forming an opening on the lower cover plate 13 of the single battery 1.

[0087] S3. The push rod 41 continues to slide forward to unpack the next single battery 1 until all single batteries 1 have been unpacked. During the sliding process of the push rod 41, the unpacking pieces 2 that have been separated from each single battery 1 are sleeved on the through rods 43.

[0088] S4. After unpacking all the single cells 1, take out the entire unpacking device 4 from the operation port. Subsequently, electrolyte can be injected, and the operation port can be sealed, or an explosion relief component can be installed on the operation port;

[0089] S5. Flip the entire battery pack as a whole, so that the electrolyte regions of the single cells 1 communicate with the electrolyte sharing chamber at the bottom of the housing, realizing the intercommunication of the electrolyte.

Claims

1. A battery cover, characterized in that: It includes a cover body, an opening piece and a reinforcement piece; The cover plate body is provided with a weak area; The package opening piece includes a U-shaped connecting piece and two strip plates, wherein the U-shaped connecting piece includes a middle bottom plate and two vertical plates respectively fixed on both sides of the middle bottom plate; the middle bottom plate of the U-shaped connecting piece is connected to the weak area of ​​the cover plate body, and the strip plates are two, which are respectively fixedly connected to the vertical plates of the U-shaped connecting piece to form flanges on both sides of the U-shaped connecting piece, so that an opening gap is formed between the strip plates and the cover plate body; The reinforcing member is fixed on the end surface of the middle bottom plate away from the cover plate body; Under the action of external force, the opening piece, the reinforcing piece and the weak area are separated from the cover body, so that an opening is formed in the battery cover.

2. The battery cover according to claim 1, characterized in that: The reinforcing piece has the same shape and size as the package opening piece, and the reinforcing piece is installed perpendicularly to the package opening piece.

3. The battery cover according to claim 1, characterized in that: The reinforcing piece has the same shape as the package opening piece, the length of the reinforcing piece is smaller than the length of the package opening piece, and the installation direction of the reinforcing piece is perpendicular to that of the package opening piece.

4. The battery cover according to claim 1, characterized in that: The reinforcement member comprises at least one flat plate, the size of the flat plate being the same as that of the middle bottom plate.

5. The battery cover according to claim 1, characterized in that: The package opening piece and the reinforcement piece are both integrally extruded pieces.

6. The battery cover according to any one of claims 1 to 5, characterized in that: The package opening piece is welded to the weak area of ​​the cover plate body, and the reinforcing piece is welded to the middle bottom plate of the U-shaped connecting piece.

7. The battery cover according to claim 6, characterized in that: The cover plate body is provided with a circle of annular grooves, the area circled by the annular grooves is a weak area, and the cross section of the annular grooves is U-shaped or V-shaped.

8. A single cell battery, characterized in that: The invention comprises a battery housing, wherein the battery housing comprises an upper cover plate, a lower cover plate and a cylinder, and at least one of the upper cover plate and the lower cover plate adopts the battery cover plate according to any one of claims 1 to 7.

9. The single cell according to claim 8, characterized in that: The polarity terminals of the single cells are provided with through grooves or through holes for fixing the heat transfer tubes.

Images