Shell for single battery, single battery and high-capacity battery

Abstract

The utility model belongs to the field of batteries, and relates to a shell for a single battery, the single battery and a high-capacity battery. The problems that an existing high-capacity battery is high in cost and large in weight are solved. Shells for the single batteries are made of plastic materials; the single battery comprises the shell, and the high-capacity battery comprises a plurality of single batteries; a concave part and a bulge are arranged in a shell area corresponding to the electrode assembly supporting area; the concave part is used for embedding the bulge of the other single battery and is fixedly connected with the bulge of the other single battery; under the action of external force, channels can be formed in the bulges and the concave parts, and the channels are communicated with the electrolyte regions of the inner cavities of the single battery shells; the upper cover plate is provided with a connecting piece which is used for being connected with a connecting piece on an adjacent single battery, and a channel can be formed in the connecting piece under the action of external force and is communicated with a gas area of an inner cavity of a single battery shell. The shell for the single battery provided by the utility model is made of a plastic material, and has the advantages of low cost and light weight compared with a finished battery adopted in the background technology.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the battery field, concretely is a kind of shell for single battery, single battery and large capacity battery. BACKGROUND

[0002] Chinese patent CN219658914U discloses a large capacity battery, and its structure is shown in the figure, comprising the large capacity battery main body formed by the parallel connection of a plurality of single batteries and the shared pipeline located on the large capacity battery;The shared pipeline is used to pass through the inner cavities of the plurality of single batteries to make all single batteries in the large capacity battery under one system.The large capacity battery can strengthen the uniformity of each single battery in the large capacity battery and improve the cycle life through the shared pipeline. Figure 1

[0003] The single battery in the above-mentioned patent comprises an outer shell, a sealing assembly and a finished battery, the finished battery is installed inside the outer shell, and an opening is provided on the shell body of the finished battery;The outer shell is provided with a first through hole communicated with the opening, and a pipeline 01 extending along the width or length direction of the outer shell, the side wall of the pipeline is provided with a second through hole communicated with the first through hole;The sealing assembly is arranged on the opening, the first through hole or the second through hole.

[0004] By providing the first through hole and the pipeline with the second through hole on the outer shell of the single battery, the shared pipeline 02 can be formed through the pipeline when the large capacity battery is formed;Moreover, by sleeving the outer shell on the finished battery, the existing finished battery production line can be used, and the finished battery can be put into production after slight improvement.

[0005] However, this design has some shortcomings, usually the finished battery shell and the outer shell are made of aluminum shell, which makes the overall cost of the large capacity battery higher, and the weight is larger.

[0006] From the cost point of view, aluminum itself is a relatively high-priced metal material, and the processing technology of aluminum shell is complex, which needs to go through multiple processes such as cutting, stamping, welding, etc., and the requirements for processing equipment and technology are also higher. These factors inevitably lead to a substantial increase in the manufacturing cost of large capacity battery.

[0007] From the weight point of view, the superposition of two aluminum parts can significantly increase the overall weight of the large capacity battery. This is extremely disadvantageous for the use, storage and transportation of the large capacity battery. SUMMARY

[0008] The utility model aims at providing a kind of shell for single battery, single battery and large capacity battery, overcome the technical problems of higher cost and larger weight of existing large capacity battery.

[0009] ​The utility model discloses a concept is:

[0010] The utility model mainly sets out from monomer battery own structure and the packaging structure of monomer battery two aspects, solves above -mentioned technical problem:

[0011] Firstly, set out from monomer battery own structure, reduce the cost and weight of large capacity battery;

[0012] In view of the fact that the density of plastic material is lower than that of metal aluminum material and the cost is relatively lower, the utility model plans to replace the finished battery in the background technology with the finished battery (finished battery can also be called monomer battery) using plastic shell.

[0013] Compared with the traditional metal aluminum shell, the weight of the plastic shell is significantly reduced. At the same time, the cost of plastic material is lower, and the production process is relatively simple, without complex equipment and technology, which can effectively reduce the manufacturing cost and improve the production efficiency, and has cost advantage in large-scale production.

[0014] Secondly, set out from the packaging structure of monomer battery, reduce the weight and cost of large capacity battery;

[0015] The utility model considers that a plurality of monomer batteries with plastic shell are arranged in the same pressure shell, and the pressure shell can protect the plurality of monomer batteries. Compared with the structure of the background technology in which each monomer battery is individually sleeved with an outer shell, the packaging and protection costs are reduced, and the cost is lower. And in the case that the number of monomer batteries is the same, the weight of one pressure shell is necessarily smaller than that of a plurality of small outer shells, therefore, through the design of the pressure shell, the weight of the large capacity battery can be further reduced.

[0016] Based on the above invention concept, the utility model provides a shell for monomer battery, which is characterized in that: the shell is enclosed by an upper cover plate, a cylinder and a lower cover plate; The upper cover plate, the cylinder and the lower cover plate are all made of plastic material;

[0017] Along the height direction of the shell, the inner cavity of the shell is divided into an electrode assembly support area and an electrode assembly containing area from bottom to top;

[0018] A first recess and a first protrusion are arranged in the shell area corresponding to the electrode assembly support area; The first recess is used for embedding and fixedly connecting the first protrusion on another shell for monomer battery; Under the action of external force, a channel can be formed in the first recess and the first protrusion, and the channel is communicated with the electrolyte area in the inner cavity of the monomer battery shell;

[0019] The upper cover plate is provided with a connecting piece for connecting with the connecting piece on the adjacent monomer battery, and under the action of external force, a channel can be formed in the connecting piece, and the channel is communicated with the gas area in the inner cavity of the monomer battery shell.

[0020] When the individual battery is connected by the first recess and the first protrusion, the utility model utilizes the tool to open the channel through the electrolyte area in the single battery shell cavity, so the electrolyte between the individual battery is connected, and the individual battery is in the same electrolyte system, the channel through the gas area in the single battery shell cavity is opened in the connecting piece, the gas between the individual battery is connected, and the gas balance is achieved, the difference of the individual battery is improved from the electrolyte and the gas, the consistency of the individual battery in the charging and discharging process is guaranteed, the overall service life is prolonged, and the performance of the large capacity battery is improved.

[0021] The shell for the individual battery provided by the utility model adopts a plastic material, and has the advantages of low cost and light weight compared with the finished product battery in the background art.

[0022] Meanwhile, the electrode assembly support area in the shell is fully utilized, the first recess and the first protrusion are arranged in the area, and the first recess and the first protrusion do not affect the size of the individual battery in the height direction, so that the stability of the connection is guaranteed, and the compactness and the space utilization efficiency of the large capacity battery as a whole are considered.

[0023] Further, the connecting piece is a second recess and a second protrusion arranged on the opposite side walls of the upper cover plate; the second recess is used for embedding the second protrusion of another individual battery and fixedly connecting, and under the action of external force, a channel can be opened in the second recess and the second protrusion, and the channel is through the gas area in the single battery shell cavity.

[0024] The utility model fully utilizes the structure of the upper cover plate, arranges the second recess and the second protrusion on the opposite side walls of the upper cover plate, and the second recess and the second protrusion do not affect the size of the individual battery in the height direction, so that the compactness and the space utilization efficiency of the large capacity battery as a whole are considered. Meanwhile, when the large capacity battery is assembled, the second protrusion of one individual battery is inserted into the second recess of another individual battery and fixedly connected, so that the stability between the individual batteries can be improved, and the structure of the large capacity battery is more stable and durable.

[0025] Further, the second recess is a second blind hole opened in the first side wall of the upper cover plate; the second protrusion is a second butt joint pipe arranged on the outer wall of the second side wall of the upper cover plate; the second butt joint pipe is used for being inserted into the second blind hole of another individual battery and fixedly connected; and the first side wall of the upper cover plate and the second side wall of the upper cover plate are parallel to each other.

[0026] The utility model discloses adopt second blind hole and second butt joint pipe cooperation, and the connecting process is simple and convenient, can complete the connection of each monomer battery fast and accurately, makes the assembly process of whole large capacity battery more orderly, efficient. And when they are mutually inserted and fixed, form a kind of connection form similar to mortise and tenon structure, ensure that reliable connection is formed between adjacent monomer battery, make the whole large capacity battery when being subjected to vibration, impact, monomer battery between will not easily loosen, shift and other phenomena, thereby guarantee the performance stability and service life of large capacity battery.

[0027] In addition, the second blind hole and the second butt joint pipe do not affect the sealing of the monomer battery shell.

[0028] Further, a passage is formed in the upper cover plate and communicates with the inner cavity of the second butt joint pipe; a partition plate is arranged in the passage; a cavity is formed between the partition plate and the bottom end of the second blind hole; a through hole is formed in the region of the upper cover plate corresponding to the cavity; and the through hole is arranged to communicate with the inner cavity of the monomer battery.

[0029] Under the action of external force, the partition plate and the bottom end of the second blind hole can be opened, so that the inner cavity of the second butt joint pipe, the inner cavity of the passage and the inner cavity of the second blind hole all communicate with the inner cavity of the monomer battery.

[0030] By forming the passage in the upper cover plate and communicating with the inner cavity of the second butt joint pipe, the second butt joint pipe inner cavity and the monomer battery inner cavity can be communicated through external force in the later stage; meanwhile, the inner cavity of the passage communicates with the inner cavity of the monomer battery through the through hole formed in the upper cover plate; in order to ensure that the internal environment of the monomer battery is not affected by the external environment, the partition plate is arranged to isolate the through hole from the inner cavity of the second butt joint pipe; in the later stage, when the inner cavities of the monomer batteries need to be communicated, the partition plate and the bottom end of the second blind hole are opened under the action of external force, so that the inner cavity of the second butt joint pipe, the inner cavity of the passage and the inner cavity of the second blind hole all communicate with the inner cavity of the monomer battery.

[0031] Further, the connecting piece can also be a sub-pipe segment arranged on the upper surface of the upper cover plate; the sub-pipe segment is a hollow pipe; the hollow pipe and the upper cover plate are provided with openings that communicate with each other; and the two ends of the hollow pipe are closed ends.

[0032] The two closed ends are defined as a first closed end and a second closed end, respectively.

[0033] A third blind hole extending in the axial direction is formed in the first closed end; the third blind hole is used for inserting and fixedly connecting the second closed end of another hollow pipe of a monomer battery.

[0034] Under the action of external force, the first closed end and the second closed end of the hollow pipe can be opened.

[0035] The utility model discloses a hollow pipe structure is adopted to the sub -pipe section, and the both ends are made as closed ends.

[0036] On the one hand, when the plurality of single batteries are assembled, the adjacent single batteries are stably connected by the sub -pipe section, the stability of single battery in the box is greatly promoted, and the structure of the whole large capacity battery presents more optimal stability and durability.

[0037] On the other hand, the two closed ends of the sub -pipe section can be smoothly opened under the specific action of external force. Once the closed end is opened, the inner cavities of all sub -pipe sections are immediately through, and further realize the through of all single battery inner cavities. In this way, the difference between each single battery can be effectively improved, the consistency of each single battery in the charging and discharging process is guaranteed, the overall service life is prolonged, and the performance of the large capacity battery is improved.

[0038] Further, the first recess is a first blind hole formed in the first side wall of the lower cover plate; the first protrusion is a first butt joint pipe arranged on the outer wall of the second side wall of the lower cover plate; the first butt joint pipe is used for embedding in the first blind hole of another single battery and fixedly connected, and the first side wall of the lower cover plate and the second side wall of the lower cover plate are parallel to each other.

[0039] The utility model discloses the first blind hole and the first butt joint pipe are connected, and the connection process is simple and convenient, and the connection of each single battery can be quickly and accurately completed, so that the assembly process of the whole large capacity battery is more orderly and efficient. When they are embedded and fixed, reliable connection is formed between the adjacent single batteries, so that the single batteries are not easily loose, displace and the like when the whole large capacity battery is subjected to vibration and impact, and the stable electrical connection and structure state can be maintained for a long time.

[0040] In addition, the arrangement of the first blind hole and the first butt joint pipe does not affect the sealing of the single battery shell.

[0041] Further, the inner surface of the lower cover plate is provided with a plurality of bosses arranged in an array, the top of the boss is used for supporting the electrode assembly, and the gap between the bosses is used as an electrolyte flow channel.

[0042] The regularly arranged plurality of bosses can provide stable and uniformly distributed support points for the electrode assembly, avoid the deformation or damage of the electrode assembly caused by excessive local stress. In addition, the gap between the bosses is used as an electrolyte flow channel, so that the electrolyte can be uniformly distributed around the electrode assembly, and the electrodes of each part can fully contact the electrolyte.

[0043] Further, under the action of external force, the first blind hole bottom end and the lower cover plate second side wall area circumscribed by the first butt pipe can be opened, and the electrolyte flow channel is penetrated.

[0044] The first blind hole and the first butt pipe are both hollow structures, on the one hand, when multiple single batteries are assembled, the adjacent single batteries are stably connected by means of the first blind hole and the first butt pipe, so that the stability of the single battery in the box is greatly improved, and the structure of the whole large capacity battery presents better stability.

[0045] On the other hand, the first blind hole inner cavity and the first butt pipe inner cavity are isolated from the battery cavity under normal circumstances, but under the action of a specific external force, the first blind hole bottom end and the lower cover plate second side wall area circumscribed by the first butt pipe can be smoothly opened. Once the closed end is opened, the inner cavities of all the first blind holes and the first butt pipes are immediately penetrated with the electrolyte flow channel, and further penetrated with the inner cavities of all the single batteries. In this way, the differences that may exist between the single batteries can be effectively improved, the consistency of the single batteries in the charging and discharging process is guaranteed, the overall service life is prolonged, and the performance of the large capacity battery is improved.

[0046] Further, the upper cover plate is integrally provided with a weak part; the strength of the weak part is less than that of the rest of the upper cover plate, and when the single battery is in thermal runaway, the thermal runaway smoke breaks through the weak part and is discharged.

[0047] The weak part and the upper cover plate are integrally arranged, and at least have the following advantages:

[0048] From the structural stability, the existing explosion relief membrane is usually attached to the battery upper cover plate by pasting or other means. In the long-term use process, affected by factors such as chemical substances inside the battery, temperature changes and mechanical vibrations, the connection part of the explosion relief membrane and the upper cover plate may be loose, fall off and other problems, resulting in failure of its explosion relief function. The weak part integrally arranged in the utility model is a whole with the upper cover plate, and there is no risk of loose connection and falling off, which greatly improves the stability and reliability of the structure, and can always maintain good explosion relief performance.

[0049] In terms of sealing, the combination of the existing explosion relief membrane and the upper cover plate faces many challenges in achieving absolute sealing. The integrally arranged weak part seamlessly connects with the upper cover plate, which can effectively ensure the sealing of the battery under normal circumstances and prevent external substances from entering, providing a better environment for stable operation of the battery.

[0050] From the perspective of cost and manufacturing process, the existing explosion relief membrane needs additional materials and complex installation process, which not only increases the production cost, but also may cause uneven product quality due to human factors in the manufacturing process. The integral weak part does not need additional installation steps in the manufacturing process, simplifies the production process, reduces the production cost, and at the same time improves the consistency and quality stability of the product.

[0051] A recessed area can be provided on the upper cover plate to form a weak part. Compared with some methods of forming a weak part by changing the material composition or microstructure, the method of providing a recessed area is simpler and can more intuitively and accurately control the strength and opening pressure of the weak part. Specifically, by controlling the depth, shape and area of the recessed area, the weak part can be accurately set to open at a specific pressure, greatly improving the reliability of the explosion relief function.

[0052] A through hole along the width or length direction of the upper cover plate can also be provided on the upper cover plate to form a weak part. When a through hole along the width or length direction of the upper cover plate is provided to form a weak part, compared with a weak part formed by a recessed area, the flatness of the battery upper cover plate can be better maintained.

[0053] The above-mentioned weak part is located between the two polarity terminals of the upper cover plate. It can timely discharge the heat generated by thermal runaway and effectively alleviate the local high temperature. In addition, compared with setting the weak part in other positions, it reduces the interference with other functional areas of the battery, and realizes a more efficient layout in a limited space.

[0054] Further, the first recess and the first protrusion are both integrated with the shell; the first recess is used for embedding the first protrusion of another single battery and is fixedly connected through a hot melting mode;

[0055] The connecting piece is integrated with the upper cover plate; and the connecting piece is used for fixedly connecting with the connecting piece of another single battery through a hot melting mode.

[0056] The utility model can adopt injection molding process, integrally form the first recess and the first protrusion on the lower cover plate or the cylinder, and integrally form the connecting piece on the upper cover plate, and the processing process is simple. Since the first recess, the first protrusion and the connecting piece are formed at the same time, there is no size deviation problem caused by subsequent assembly, the precision is high, and it can be ensured that the first recess and the first protrusion of each single battery and the connecting piece can be accurately matched, which is beneficial to batch production and quality control of large-capacity batteries.

[0057] In addition, the first recess and the first protrusion, and the adjacent connectors are connected by a hot melt method, in the hot melt process, the plastic material will melt after being heated, and after cooling and solidifying, the materials will be fused together to form an integral structure, which can form a very firm combination between the recess and the protrusion, and between the adjacent connectors. This connection method can withstand a large tensile force, pressure and shear force, effectively preventing the single battery from loosening or separating during use, and ensuring the structural stability of the large capacity battery. At the same time, the hot melt connection has low precision requirements, so even if there is a certain size deviation between the recess and the corresponding protrusion, and the connector during production, accurate connection can still be achieved, greatly improving the production efficiency.

[0058] The utility model discloses a single battery, which is characterized by comprising the shell for the single battery.

[0059] Further, the shell strength is P, P1≤P≤P2;Wherein P1 is the strength requirement of the shell in the formation stage and the normal charging and discharging stage of the battery;P2 is the strength requirement of the shell in the thermal runaway stage.

[0060] The single battery shell is a sealed shell made of plastic material, which serves as a cavity for accommodating the electrode assembly and the electrolyte, and has a sealing function. At the same time, the strength of the sealed shell needs to meet the strength requirement of the shell in the formation stage and the normal charging and discharging stage of the battery;That is, the sealed shell needs to have a certain strength to ensure that it will not break during the formation stage and the normal charging and discharging stage of the battery as the internal environment of the battery changes, such as temperature and pressure. The single battery has a lower cost compared to the existing finished plastic shell single battery, and thus the entire large capacity battery also has a lower cost.

[0061] The utility model discloses a large capacity battery, which is characterized by comprising a pressure-bearing shell and n single batteries arranged in the pressure-bearing shell, wherein n is an integer greater than 1.

[0062] In the adjacent single batteries, the first protrusion of one single battery is embedded in the first recess of another single battery and is fixedly connected, and the first protrusion and the first recess are provided with a channel passing through the electrolyte area in the single battery shell cavity;The connector of one single battery is fixedly connected with the connector of another single battery, and the connector is provided with a channel passing through the gas area in the single battery shell cavity;

[0063] The pressure-bearing shell has a strength that meets the strength requirement of the shell in the thermal runaway stage, and the pressure-bearing shell is provided with a pressure relief part.

[0064] The outer box of the large-capacity battery is a pressure-bearing shell, and the strength thereof needs to meet the strength requirement of the shell in the thermal runaway stage; that is, the pressure-bearing shell needs to have good strength and can simultaneously protect multiple single batteries. In the extreme case of thermal runaway of a single battery and melting of the plastic shell, the pressure-bearing shell can form a solid barrier, effectively isolating high-temperature flames and harmful gases and preventing the spread of thermal runaway, thereby improving the safety of the large-capacity battery after thermal runaway. Compared with the structure of individually sleeving each single battery with an outer shell in the background art, the cost of individual packaging and protection is reduced, and the cost is lower. Furthermore, in the case that the number of single batteries is the same, and the material and thickness of the pressure-bearing shell are the same as those of the outer shell of each single battery in the background art, the weight of one pressure-bearing shell is necessarily less than that of multiple small outer shells, and therefore, the weight of the large-capacity battery can be further reduced through the design of the pressure-bearing shell.

[0065] Further, when each single battery is provided with a weak portion, a blast venting channel is formed between the weak portion of each single battery and the pressure-bearing shell.

[0066] The pressure-bearing shell is provided with a blast venting portion corresponding to the blast venting channel; when the single battery is in thermal runaway, the thermal runaway flue gas breaks through the weak portion, passes through the blast venting channel, breaks through the blast venting portion, and is discharged from the pressure-bearing shell. In the initial stage of thermal runaway, the thermal runaway flue gas can be orderly discharged through the blast venting channel, effectively avoiding the spread to the large-capacity battery shell, thereby preventing the further deterioration of the thermal runaway condition.

[0067] Further, the top plate of the pressure-bearing shell is provided with a relief hole corresponding to the polarity terminal of each single battery; each polarity terminal of the single battery extends out of the relief hole; and the region of the top plate of the pressure-bearing shell corresponding to the relief hole is fixedly sealed with the shell of the single battery.

[0068] Further, the large-capacity battery further comprises a heat exchange member, and the heat exchange member exchanges heat with the polarity terminal.

[0069] During the operation of the large-capacity battery, heat is easily accumulated at the polarity terminal due to current conduction, and the heat exchange member can timely remove the heat, ensuring that the polarity terminal is always in an appropriate working temperature range. This not only helps to maintain the performance stability of the single battery in the large-capacity battery and reduce the performance degradation of the battery caused by excessively high temperature, but also further improves the overall safety and reliability of the large-capacity battery, avoiding potential failures caused by local overheating.

[0070] The utility model discloses the beneficial effects are:

[0071] The single battery adopts a plastic shell, and the large-capacity battery constructed by the single battery has low cost and light weight.

[0072] Meanwhile, in order to improve the safety performance of the large capacity battery constructed by the above single battery, the utility model discloses a plurality of above-mentioned single battery is placed in the pressure containment vessel, in the extreme case of thermal runaway of single single battery, the plastic shell melts, the pressure containment vessel can form a solid heat shield, effectively isolate high temperature flame and harmful gas, prevent the spread of thermal runaway.In addition, the pressure containment vessel is used to protect a plurality of single batteries, reduce the external impact and damage of the battery in the process of transportation and use, prolong the service life of the battery, compared with the structure of the background art of each single battery individually sleeving the outer shell, reduce the cost of individual packaging and protection, and the cost is lower.And in the case that the number of single batteries is same, the weight of one pressure containment vessel is necessarily less than the weight of a plurality of small outer shells, therefore, through the design of the pressure containment vessel, the weight of the large capacity battery can be further reduced.

[0073] Meanwhile, the utility model makes full use of the electrode assembly support area in the shell, sets up the first recess and the first protrusion in the area, and the first recess and the first protrusion do not affect the size of single battery in the height direction, and the compactness and space utilization efficiency of the whole large capacity battery are considered.

[0074] And the difference of each single battery can be improved from electrolyte and gas, the consistency of each single battery in the process of charging and discharging is guaranteed, the overall service life is prolonged, and the performance of the large capacity battery is improved.In addition, the single battery is connected at different positions, the stability of the single battery in the box is effectively enhanced, so that the structure of the whole large capacity battery is more stable and durable. ACCURACY OF DRAWINGS

[0075] Figure 1 It is the structural diagram of the large capacity battery in the background art;

[0076] Figure 2 It is the structural diagram of the first view of single battery in embodiment 1;

[0077] Figure 3 It is the structural diagram of the second view of single battery in embodiment 1;

[0078] Figure 4 It is the partial structural diagram of single battery shell in embodiment 1;

[0079] Figure 5 It is the partial sectional view of the structural diagram of single battery shell in embodiment 1;

[0080] Figure 6 It is the partial structural sectional view of single battery shell in some other embodiments;

[0081] Figure 7 It is the structural diagram of the first view of the upper cover plate of single battery in embodiment 1;

[0082] Figure 8 Structure diagram of the second perspective view of the upper cover plate of the single battery in Example 1;

[0083] Figure 9 Sectional view of the upper cover plate of the single battery in Example 1;

[0084] Figure 10 Structure diagram of the first perspective view of the upper cover plate of the single battery in Example 2;

[0085] Figure 11 Structure diagram of the second perspective view of the upper cover plate of the single battery in Example 2;

[0086] Figure 12 Structure diagram of the third perspective view of the upper cover plate of the single battery in Example 2;

[0087] Figure 13 Structure diagram of the single battery in Example 2;

[0088] Figure 14 Structure diagram of the upper cover plate of the single battery in Example 4;

[0089] Figure 15 Structure diagram of another upper cover plate of the single battery in Example 4;

[0090] Figure 16 Structure diagram of the upper cover assembly of the single battery in Example 5;

[0091] Figure 17 Structure diagram of the single battery in Example 5;

[0092] Figure 18 Structure diagram of the first perspective view of another upper cover plate of the single battery in Example 5;

[0093] Figure 19 Structure diagram of the second perspective view of another upper cover plate of the single battery in Example 5;

[0094] Figure 20 Structure diagram of another single battery in Example 5;

[0095] Figure 21 Structure diagram of the large capacity battery in Example 6;

[0096] Figure 22 Exploded structure diagram of the large capacity battery in Example 6;

[0097] Figure 23 Partial exploded structure diagram of the large capacity battery in Example 6;

[0098] Figure 24 Partial exploded structural schematic view of a third large capacity battery of Example 6;

[0099] Figure 25 Partial exploded structural schematic view of a third large capacity battery of Example 6;

[0100] Figure 26 Partial exploded structural schematic view of a fourth large capacity battery of Example 6;

[0101] Figure 27 Partial exploded structural schematic view of a fifth large capacity battery of Example 6;

[0102] Figure 28 Partial exploded structural schematic view of a sixth large capacity battery of Example 6;

[0103] Figure 29 Structural schematic view of a sixth large capacity battery of Example 6.

[0104] Reference signs in the drawings are:

[0105] 01, pipe; 02, shared pipe;

[0106] 1, upper cover plate; 11, polarity terminal; 2, barrel; 3, lower cover plate; 31, first blind hole; 32, bottom end of first blind hole; 33, first butt joint pipe; 4, electrode assembly support area; 5, electrode assembly containing area; 6, first recess; 7, first protrusion; 10, sub-pipe segment; 12, boss; 13, pressure-bearing shell; 14, heat exchange member; 15, single battery; 16, explosion venting portion; 17, avoidance hole; 18, third blind hole; 19, opening; 21, second recess; 23, second protrusion; 24, first side wall of upper cover plate; 25, second side wall of upper cover plate; 26, second blind hole; 261, stepped surface of counterbore; 262, bottom end of second blind hole; 27, second butt joint pipe; 28, passage; 29, through hole; 210, partition plate; 42, through slot; 45, recess; 46, through hole. DETAILED DESCRIPTION

[0107] In order to make the above objectives, characteristics and advantages of the present application more apparent, more understandable, the specific embodiments of the present application will be described in detail below with reference to the drawings of the specification. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the protection scope of the present application.

[0108] Many specific details are set forth in the following description in order to provide a thorough understanding of the present application. However, the present application can be practiced according to other embodiments that are not specifically described in the following description. Furthermore, well-known methods can not be described in detail in order to avoid obscuring the present application. Accordingly, the present application is not limited to the embodiments described herein.

[0109] In the description of the present application, it should be noted that the orientation or positional relationship indicated by the terms "top, bottom" and the like in the description is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first, second, third, fourth, etc." are only for the purpose of description and cannot be understood as indicating or implying relative importance.

[0110] Embodiment 1

[0111] As shown in Figure 2 and Figure 3 , it is a structural schematic diagram of the single battery 15 of the present embodiment, which comprises a shell and an electrode assembly and an electrolyte in the inner cavity of the shell; the shell is enclosed by the upper cover plate 1, the cylinder 2 and the lower cover plate 3.

[0112] In order to reduce the cost and the weight of the battery, the plastic shell is adopted in the present embodiment. The lower cover plate 3 and the cylinder 2 can be molded at one time by injection molding process, without the need of separate processing and then assembling, which greatly reduces the production process and shortens the production cycle. Moreover, the injection molding integral part has uniform material distribution and close combination during the molding process, so that the connection between the battery lower cover plate 3 and the cylinder 2 is more firm, and the overall structural strength is higher. In addition, the reinforcing ribs can be integrally formed on the cylinder 2, which effectively increases the bending, compression and torsion resistance of the cylinder 2.

[0113] In the present embodiment, the upper cover plate 1 and the cylinder 2 can be connected by hot melting or welding sealing. The connection between the upper cover plate 1 and the cylinder 2 is continuous, uniform and close, with very high stability. The water, dust and other impurities outside cannot enter the inside of the battery, and the electrode assembly can be well protected, and the performance and service life of the battery are also guaranteed.

[0114] It should be noted that in the present application, the plastic material selected should have the following properties:

[0115] 1. It has enough strength to ensure the stability of the battery structure;

[0116] 2. It has chemical corrosion resistance and can resist the corrosion of electrolyte;

[0117] Three, with barrier properties, can effectively prevent the battery inside the electrolyte, gas and other substances to the outside leakage, while also prevent the outside moisture, oxygen and other impurities into the battery inside;

[0118] Four, with good thermal stability, the battery in the charging and discharging process will produce heat, especially in high rate charging and discharging, will produce more heat. The plastic material needs to maintain stable performance within a certain temperature range, will not soften, deformation or decomposition due to high temperature.

[0119] The plastic material used can be the material used by the existing plastic shell monomer battery 15, and can also be the plastic material disclosed in Chinese patents CN106543551A and CN106977894A.

[0120] For ease of description, the embodiment defines the width direction of the monomer battery 15 with the shell as the x direction, the length direction as the y direction, and the height direction as the z direction.

[0121] In this embodiment, the shell cavity is divided into an electrode assembly support area 4 and an electrode assembly containing area 5 along the z direction from bottom to top.

[0122] In combination with Figure 4 and Figure 5 It can be seen that in the embodiment, the electrode assembly support area 4 is mainly located on the lower cover plate 3; the electrode assembly containing area 5 is located above the electrode assembly support area 4.

[0123] In other embodiments, as shown in Figure 6 , the electrode assembly support area 4 can be enclosed by the lower cover plate 3 and part of the area of the cylinder 2 connected thereto; the electrode assembly containing area 5 is located above the electrode assembly support area 4.

[0124] The utility model is provided with a first recess 6 and a first protrusion 7 on the shell area corresponding to the electrode assembly support area 4; wherein the first recess 6 is used for embedding the first protrusion 7 on the shell of another monomer battery 15 and fixedly connecting. Under the action of external force, a channel can be opened in the first recess 6 and the first protrusion 7, and the channel is through with the electrolyte area in the shell cavity of the monomer battery 15.

[0125] The first recess 6 and the first protrusion 7 of the utility model are inserted into each other, corresponding to the connection of multiple monomer batteries 15, which can also improve the stability of the monomer battery 15 in the large-capacity battery, make the structure of the whole large-capacity battery more compact and stable, effectively resist the interference under various working conditions, and ensure the continuous, efficient and safe operation of the large-capacity battery.

[0126] The utility model discloses a first recess 6 and first protrusion 7 are all arranged on the shell corresponding to electrode assembly support area 4, make first recess 6 and first protrusion 7 in the height direction of monomer battery 15 will not produce additional size increment. For large capacity battery, especially in some space demanding application scenarios, this kind of connection structure that does not increase the height direction size is particularly important. It can let large capacity battery in limited space contain more monomer battery 15, or under the condition of meeting the same battery capacity demand, make large capacity battery whole more small and exquisite, facilitate the carrying, installation and layout optimization of equipment.

[0127] Since the shell of the embodiment is of plastic material, the shell (the shell here is composed of the lower cover plate 3 and the cylinder 2) with the first recess 6 and the first protrusion 7 can be integrally formed by using the injection molding process; the size of the mold cavity can be accurately controlled during the injection molding process, so that the first recess 6 and the first protrusion 7 can achieve high dimensional accuracy when formed, ensuring precise cooperation with other monomer batteries 15. Moreover, since it is integrally formed, there is no problem of cumulative dimensional deviation caused by the assembly process, ensuring the stability and consistency of the connection of the monomer batteries 15, which is conducive to improving the overall performance and quality stability of the large capacity battery and reducing problems such as poor connection, abnormal battery operation, etc. caused by size mismatch. At the same time, after the first protrusion 7 of one of the adjacent monomer batteries 15 is embedded in the first recess 6 of the other monomer battery 15, the two can be fixedly connected by a hot melting method. After the plastic is hot melted and cooled and solidified, the two are fused together to form a stable connection structure that can withstand a large mechanical stress. For example, when the large capacity battery is subjected to external forces such as vibration, impact, and extrusion, the connection between the monomer batteries 15 is effectively prevented from loosening or disengaging, ensuring the structural integrity and electrical connection stability of the large capacity battery under complex working conditions, thereby improving the safety and reliability of the large capacity battery and prolonging its service life. In addition, the hot melting connection method has a low precision requirement, and even under a certain degree of dimensional deviation, good connection can be achieved through hot melting, reducing the precision control cost in the production process.

[0128] From Figure 2 and Figure 3 It can be seen that the first recess 6 and the first protrusion 7 of the embodiment are respectively arranged on the first side wall and the second side wall of the shell which are parallel to each other. In addition, two first recesses 6 can be provided on the first side wall, and two first protrusions 7 can be provided on the second side wall correspondingly.

[0129] In other embodiments, one first recess 6 and one first protrusion 7 can be provided on the first side wall, and one first protrusion 7 and one first recess 6 can be provided on the second side wall correspondingly.

[0130] In this embodiment, when assembling a large-capacity battery, the operator can easily distinguish the correspondence between the first recess 6 and the first protrusion 7, and can quickly and accurately connect each individual battery cell 15. However, if there are both first recesses 6 and first protrusions 7 on the same side wall, the operator needs to be more careful in distinguishing which first recess 6 corresponds to which first protrusion 7 during assembly. If not careful, mismatch may occur, resulting in reduced assembly efficiency.

[0131] It should be noted that:

[0132] 1. The first sidewall mentioned above is composed of the first sidewall of the cylinder 2 and the first sidewall of the lower cover plate; the second sidewall mentioned above is composed of the second sidewall of the cylinder 2 and the second sidewall of the lower cover plate.

[0133] 2. The first and second sidewalls described above are parallel to each other and can both be parallel to the xz plane. When parallel to the xz plane, both the first protrusion 7 and the first recess 6 extend along the y direction. Alternatively, both the first and second sidewalls described above can be parallel to the yz plane. When parallel to the yz plane, both the first protrusion 7 and the first recess 6 extend along the x direction.

[0134] The following example mainly focuses on the first and second sidewalls being parallel to the yz plane.

[0135] from Figure 5 As can be seen, in this embodiment, the first recess 6 is a first blind hole 31 opened on the first side wall of the lower cover plate, that is, the opening end of the first blind hole 31 is located on the first side wall of the lower cover plate, and the bottom end 32 of the first blind hole is located in the electrode assembly support area 4. The first protrusion 7 is a first pair of connecting tubes 33 provided on the outer wall of the second side wall of the lower cover plate; the first pair of connecting tubes 33 is used to be embedded in the first blind hole 31 of another single cell 15 and fixedly connected.

[0136] In some other embodiments, the first recess 6 may also be employed. Figure 6 The structure shown, namely the first recess 6, can be a sub-tube segment 10 disposed on the first side wall of the cylinder 2; the sub-tube segment 10 extends along the x-direction, with one end closed and the other end open; the closed end is located within the electrode assembly support area 4, and the open end penetrates through the first side wall of the cylinder and is located on the first side wall of the cylinder. The first protrusion 7 is a first pair of connecting pipes 33 disposed on the outer wall of the second side wall of the cylinder 2; the first pair of connecting pipes 33 is used to embed into the first blind hole 31 of another single cell 15 and to fix it in place.

[0137] In some other embodiments, the first protrusion 7 can also be a solid column, which has higher strength and can withstand greater tensile and compressive forces. However, compared to this embodiment, it is more difficult to create a through-hole channel in it that penetrates the inner cavity of the shell.

[0138] from Figure 4 and Figure 5It can also be seen that this embodiment has multiple protrusions 12 arranged in an array on the inner surface of the lower cover plate 3. The tops of the protrusions 12 are used to support the electrode assembly, and the gaps between the protrusions 12 serve as electrolyte flow channels. The aforementioned multiple protrusions 12 can be arranged in a rectangular array or a ring array, etc.; the regularly arranged multiple protrusions 12 can provide stable and uniformly distributed support points for the electrode assembly, avoiding the situation where excessive local stress leads to deformation or damage of the electrode assembly. In addition, using the gaps between the protrusions 12 as electrolyte flow channels allows the electrolyte to be evenly distributed around the electrode assembly, ensuring that the electrodes in each part can fully contact the electrolyte.

[0139] Furthermore, during battery operation, if the temperature rises, the electrolyte stored in the electrolyte flow channel 28 can quickly absorb heat through heat transfer, dispersing the absorbed heat throughout the casing and dissipating it through the casing surface. This effectively prevents battery overheating, reduces the risk of thermal runaway, precisely regulates temperature, and maintains battery performance.

[0140] In addition, in this embodiment, both the first blind hole 31 and the first connecting pipe 33 are hollow structures. After being constructed into a high-capacity battery, under the action of external force, the area of ​​the second side wall of the lower cover plate enclosed by the bottom end 32 of the first blind hole and the first connecting pipe 33 will be hollow. Figure 5 The area shown in the middle circle (a) can be opened, immediately connecting the inner cavities of all the first blind holes 31 and the first connecting pipe 33, and further connecting them with the electrolyte areas of all individual battery cells 15, achieving electrolyte sharing. In this way, the differences that may have existed between individual battery cells 15 can be effectively improved, ensuring the consistency of each individual battery cell 15 during charging and discharging, extending the overall service life, and improving battery performance.

[0141] If adopted Figure 6 The structure shown, after being constructed into a high-capacity battery, under the action of external force, the closed end of the sub-tube segment 10 and the second side wall area of ​​the lower cover plate enclosed by the first pair of tubes 33 ( Figure 6 The area shown in the middle circle (a) can be opened, immediately connecting the inner cavities of all sub-tube segments 10 and the first pair of tubes 33, and further connecting them with the inner cavities of all individual cells 15. This can also improve the differences that may exist between individual cells 15, ensure the consistency of each individual cell 15 during charging and discharging, extend the overall service life, and improve the performance of the battery.

[0142] The above-mentioned external force generally refers to using appropriate tools to apply a certain force to the second side wall area of ​​the lower cover plate enclosed by the bottom end 32 of the first blind hole (or the closed end of the sub-pipe section 10) and the first connecting pipe 33, causing it to break and form an opening.

[0143] like Figure 7 and Figure 8As shown, it is a structural schematic diagram of the upper cover plate 1 of the single battery 15 in this embodiment.

[0144] In this embodiment, the second recess 21 and the second protrusion 23 are arranged on the opposite side walls of the upper cover plate 1 as connecting members; when assembling the large-capacity battery, the second protrusion 23 of one single battery 15 can be inserted into the second recess 21 of another single battery 15 and fixedly connected, and under the action of external force, a channel can be opened in the second recess 21 and the second protrusion 23, which is in communication with the gas area in the cavity of the single battery 15.

[0145] In addition, the second recess 21 and the second protrusion 23 cooperate with the first protrusion 7 and the first recess 6 to connect adjacent single batteries 15 from different positions, improve the stability of the single battery 15 in the large-capacity battery, make the structure of the whole large-capacity battery more compact and stable, effectively resist the interference under various working conditions, and ensure the continuous, efficient and safe operation of the large-capacity battery.

[0146] In this embodiment, the second recess 21 and the second protrusion 23 are arranged on the opposite side walls of the upper cover plate 1, so that the second recess 21 and the second protrusion 23 do not increase the size in the height direction of the single battery 15. For large-capacity batteries, especially in some application scenarios with strict space requirements, such a connection structure that does not increase the size in the height direction is particularly important. It can accommodate more single batteries 15 in a limited space, or make the large-capacity battery more compact and portable under the condition of meeting the same battery capacity demand, which is convenient for the carrying, installation and layout optimization of the equipment.

[0147] The upper cover plate 1 of the embodiment can be integrally formed by injection molding process with the second recess 21 and the second protrusion 23. The size of the mold cavity can be accurately controlled during the injection molding process, so that the second recess 21 and the second protrusion 23 can achieve high dimensional accuracy when formed, ensuring precise matching with other single batteries 15. Moreover, since it is integrally formed, there is no problem of cumulative dimensional deviation caused by the assembly process, ensuring the stability and consistency of the connection of the single batteries 15, which is conducive to improving the performance and quality stability of the large-capacity battery as a whole, reducing the problems of poor connection, abnormal battery operation and other problems caused by size mismatch. At the same time, after the second protrusion 23 of one of the adjacent single batteries 15 is inserted into the second recess 21 of the other single battery 15, the two can be fixedly connected by a hot melting method. The plastic cools and solidifies after hot melting, so that the two are integrated into one, forming a stable connection structure that can withstand a large mechanical stress. For example, when the large-capacity battery is subjected to external forces such as vibration, impact, and extrusion, the connection between the single batteries 15 is effectively prevented from loosening or disengaging, ensuring the structural integrity and electrical connection stability of the large-capacity battery under complex working conditions, thereby improving the safety and reliability of the large-capacity battery and prolonging its service life. In addition, the hot melting connection method has lower precision requirements. Even with a certain degree of dimensional deviation, good connection can be achieved through hot melting, reducing the precision control cost during the production process.

[0148] From Figure 7 and Figure 8 It can be seen that the second recess 21 and the second protrusion 23 of the embodiment are respectively arranged on the first side wall and the second side wall of the upper cover plate 1 which are parallel to each other. In addition, two second recesses 21 can be arranged on the first side wall 24 of the upper cover plate, and two second protrusions 23 can be arranged on the second side wall 25 of the upper cover plate correspondingly.

[0149] In other embodiments, one second recess 21 and one second protrusion 23 can be arranged on the first side wall 24 of the upper cover plate, and one second protrusion 23 and one second recess 21 can be arranged on the second side wall 25 of the upper cover plate correspondingly.

[0150] In the embodiment, the operator can easily distinguish the corresponding relationship between the second recess 21 and the second protrusion 23 when assembling the large-capacity battery, and can quickly and accurately connect each single battery 15. However, when there are both second recesses 21 and second protrusions 23 on the same side wall, the operator needs to be more careful to distinguish which second recess 21 corresponds to which second protrusion 23 when assembling, and a slight oversight may result in a matching error, leading to a decrease in assembly efficiency.

[0151] It should be noted that the first side wall 24 and the second side wall 25 of the upper cover plate are parallel to each other, and can be parallel to the xz plane. When parallel to the xz plane, the second protrusion 23 and the second recess 21 extend along the y direction. The first side wall 24 and the second side wall 25 of the upper cover plate can also be parallel to the yz plane. When parallel to the yz plane, the second protrusion 23 and the second recess 21 extend along the x direction.

[0152] Hereinafter, the first side wall 24 and the second side wall 25 of the upper cover plate are taken as examples.

[0153] As shown in Figure 9 , the second recess 21 in the embodiment is a second blind hole 26 opened in the first side wall 24 of the upper cover plate, that is, the opening end of the second blind hole 26 is located in the first side wall 24 of the upper cover plate. The inner cavity of the second blind hole 26 is used to accommodate the second protrusion 23 of another single battery 15, and is fixedly connected with the second protrusion 23 based on a hot melt manner.

[0154] In other embodiments, the second recess 21 can also be a groove 45 opened in the first side wall 24 of the upper cover plate.

[0155] As can be seen from Figure 9 , the second blind hole 26 in the embodiment adopts a counterbore structure, and the step surface 261 of the counterbore is used to cooperate with the end surface of the second protrusion 23. When the second protrusion 23 is inserted into the second blind hole 26, the step surface tightly abuts against the end surface of the second protrusion 23, and limits the second protrusion 23 in the axial direction. Effectively prevent unnecessary displacement of the second protrusion 23 in the axial direction, thereby avoiding problems such as loose connection and poor contact caused by displacement, and ensuring that the large-capacity battery always maintains a stable connection state between the single batteries 15 during long-term use.

[0156] The second protrusion 23 is a second butt joint pipe 27 arranged on the second side wall 25 of the upper cover plate; the second butt joint pipe 27 is used to be inserted into the second blind hole 26 of another single battery 15, and is fixedly connected based on a hot melt manner. The second butt joint pipe 27 adopts a hollow structure, which effectively reduces the overall weight while ensuring the connection function.

[0157] In other embodiments, the second protrusion 23 can also be a solid column. Compared with the hollow structure of the second butt joint pipe 27, the solid column has higher strength and can withstand greater tension and pressure. However, compared with the embodiment, it is more difficult to open a channel through the inner cavity of the shell of the single battery 15 thereon.

[0158] The second blind hole 26 of the embodiment can be two, each of which extends along the x direction, and the two second blind holes 26 are arranged along the y direction and located outside the two polarity terminals 11 respectively; correspondingly, the second connecting pipe 27 is also two, which has a one-to-one correspondence with the two second blind holes 26. Each of the two second connecting pipes 27 extends along the x direction, and the two second connecting pipes 27 are arranged along the y direction and located outside the two polarity terminals 11 respectively.

[0159] From the perspective of force, the above arrangement enables the adjacent single batteries 15 to be evenly distributed in the corresponding parts of the battery through the two second connecting pipes 27 and the second blind hole 26 when the large-capacity battery is subjected to complex external forces from different directions after being connected, avoiding the situation that the local force is too large to cause damage to the connection structure or displacement of the single battery 15.

[0160] In addition, the second blind hole 26 and the second connecting pipe 27 of the embodiment are both hollow structures, and after the large-capacity battery is constructed, the inner cavities of the second blind hole 26 and the second connecting pipe 27 can be mutually penetrated, and a through hole 29 is provided on the corresponding position of the upper cover plate 1 on the penetrated passage, so that the inner cavities of all second blind holes 26 and the inner cavities of all second connecting pipes 27 are immediately penetrated, and further penetrate the gas area of the inner cavities of all single batteries 15, achieving gas balance (in order to facilitate description, the large-capacity battery in which the gas area of the inner cavities of all single batteries 15 is penetrated is defined as a large-capacity battery). In this way, the differences that may exist between the single batteries 15 can be effectively improved, ensuring the consistency of the single batteries 15 during the charging and discharging process, prolonging the overall service life and improving the performance of the large-capacity battery.

[0161] Specifically, in order to facilitate the penetration of the inner cavities of the second blind hole 26 and the second connecting pipe 27, as shown in Figure 9 the embodiment, a channel 28 is provided on the upper cover plate 1, which penetrates the inner cavity of the second connecting pipe 27. The channel 28 is isolated from the inner cavity of the second blind hole 26 by the bottom end 262 of the second blind hole. At the same time, a through hole 29 is provided on the upper cover plate 1, which penetrates the inner cavity of the channel 28, and a partition plate 210 is also provided in the channel 28, so that the inner cavity of the single battery 15 is isolated from the external environment.

[0162] The partition plate 210 and the bottom end 262 of the second blind hole described above at least have the following functions:

[0163] First, before or during the construction of the large-capacity battery, prevent external substances from entering the interior of the single battery 15;

[0164] The partition plate 210 and the bottom end of the second blind hole 262 play a vital role in the use of the single battery 15. Before and during the construction of the large capacity battery, the single battery 15 is in an independent state, and if the internal environment of the battery is affected by the external environment, the performance of the battery will be damaged. For example, if the air in the external environment enters the internal environment of the battery through the second connecting pipe 27, the channel 28, the through hole 29 or the bottom end of the second blind hole 262, the through hole 29, an oxidation reaction may be triggered, affecting the chemical reaction balance inside the battery; the entry of water may cause internal short circuit or corrosion of the electrode of the battery; and the entry of other impurities may also damage the electrochemical system inside the battery.

[0165] The partition plate 210 and the second blind hole 26 are specifically provided in this embodiment, and the purpose is to build a solid barrier to ensure that air, water and other impurities in the external environment cannot enter the internal environment of the single battery 15 through the through hole 29 through the opening part of the second connecting pipe 27 and the second blind hole 26.

[0166] To achieve this function, the strength of the partition plate 210 is required. It needs to have certain structural strength and sealing performance to resist various pressures and erosions that may exist in the external environment, so as to create a stable and pure environment for the internal environment of the single battery 15 and protect the performance of the battery from the adverse effects of external factors.

[0167] Secondly, the partition plate 210 and the bottom end of the second blind hole 262 can be opened by the opening tool to achieve the function of gas communication;

[0168] After being constructed into a large capacity battery, the partition plate 210 and the bottom end of the second blind hole 262 need to be opened by a special opening tool, so that the internal cavity gas zones of all single batteries 15 are connected, and the construction of the large capacity battery is completed.

[0169] In order to meet this functional requirement, the partition plate 210 and the bottom end of the second blind hole 262 must have the characteristics of being able to be opened by the opening tool. This requires that when designing the partition plate 210 and the bottom end of the second blind hole 262, it should be considered that it can be smoothly opened under the action of the opening tool, and in the opening process, it will not cause damage to other parts of the large capacity battery, ensuring the integrity and functionality of the large capacity battery are not affected.

[0170] In addition, as shown in Figs. Figure 2 , Figure 3 , Figure 7 and Figure 8 , the embodiment can also open a through slot 42 on the upper surface of the upper cover plate 1, and the area of the upper cover plate 1 corresponding to the bottom of the through slot 42 is used as a weak part. When thermal runaway occurs in the single battery 15, the internal cavity pressure reaches a certain requirement, and the thermal runaway flue gas breaks through the weak part to form an opening, and is discharged from the opening of the weak part.

[0171] In some other embodiments, a ring-shaped groove can also be formed on the upper cover plate 1, and the area enclosed by the ring-shaped groove can be the weak part.

[0172] As can be seen from Figure 7 , the through groove 42 in this embodiment extends through the upper cover plate 1 along the x direction and is located between the two polarity terminals 11 of the upper cover plate 1.

[0173] From the perspective of thermal management, the polarity terminal 11 is usually a concentrated area of heat generation of the battery. By placing the weak part near the two polarity terminals 11, the heat generated by thermal runaway can be discharged in time, the local high temperature can be effectively relieved, and the heat distribution inside the battery can be optimized.

[0174] In terms of structural layout, such a setting makes the structure of the battery upper cover plate 1 more compact and reasonable. Compared with placing the weak part in other positions, it reduces the interference with other functional areas of the battery and realizes a more efficient layout in a limited space.

[0175] In some other embodiments, the through groove 42 can also extend through the upper cover plate 1 along the length direction of the upper cover plate 1, and the position where the polarity terminal 11 is located can be avoided.

[0176] The depth and width of the through groove 42 can be set according to specific needs to ensure that the area of the upper cover plate 1 where the groove bottom is located can be opened under a set pressure.

[0177] However, it should be noted that the depth and width of the through groove 42 cannot be too large. If the size exceeds a reasonable range, the through groove 42 part may be deformed due to insufficient strength when the battery does not occur thermal runaway, thereby affecting the performance of the battery. Therefore, in the design stage, various stresses that the upper cover plate 1 bears when the battery is normally running, including internal pressure, external vibration, etc., need to be comprehensively considered. By reasonably planning the corresponding size of the through groove 42, the structure of the upper cover plate 1 can be ensured to be stable under normal working conditions, and at the same time, it can be ensured that the through groove 42 can reliably play the explosion venting function when thermal runaway occurs.

[0178] In this embodiment, the top cover 1 is made of plastic and can be integrally molded using injection molding to form a top cover 1 with a second recess, a second protrusion, and a through groove 42. The low density of the plastic material significantly reduces the overall weight of the battery. Simultaneously, thanks to the good plasticity of the plastic, the injection molding process allows for precise control of the mold cavity dimensions, ensuring high dimensional accuracy of the second recess and second protrusion during molding, guaranteeing precise fit with other individual battery cells 15. Furthermore, because it is integrally molded, there is no issue of accumulated dimensional deviations due to the assembly process, ensuring the stability and consistency of the individual battery cell connections. This is beneficial for improving the overall performance and quality stability of the large-capacity battery, reducing problems such as poor connection and abnormal battery operation caused by dimensional mismatch. Additionally, in adjacent individual battery cells 15, after the second protrusion of one individual battery cell 15 is inserted into the second recess of another individual battery cell 15, the two can be fixedly connected by heat fusion. After the plastic is melted and cooled, it solidifies, fusing the two together to form a stable connection structure capable of withstanding significant mechanical stress. For example, when a large-capacity battery is subjected to external forces such as vibration, impact, or compression, it effectively prevents the connections between individual cells from loosening or detaching. This ensures the structural integrity and electrical connection stability of the large-capacity battery under complex operating conditions, thereby improving its safety and reliability and extending its lifespan. Furthermore, the hot-melt connection method has lower precision requirements; even with a certain degree of dimensional deviation, a good connection can be achieved through hot melting, reducing the cost of precision control during the production process.

[0179] The one-piece molded through-slot 42 also avoids additional splicing gaps, ensuring the overall sealing of the top cover 1 and effectively preventing the intrusion of external impurities. In addition, the injection molding process is low-cost and highly efficient, reducing processing steps and production costs, resulting in significant economic benefits in large-scale production.

[0180] Example 2

[0181] Unlike Example 1, as Figure 10 , Figure 11 and Figure 12 As shown, in this embodiment, a sub-tube segment 10 is provided on the upper surface of the upper cover plate 1 as a connector. The inner cavity of the sub-tube segment is used to communicate with the inner cavity of the individual battery cell 15. By connecting the corresponding sub-tube segments of multiple individual batteries 15, a shared pipeline can be formed. In addition, connecting the sub-tube segments of multiple individual batteries 15 can also improve the stability of the individual battery cell 15 in the large-capacity battery, making the structure of the entire large-capacity battery more compact and stable, effectively resisting interference under various operating conditions, and ensuring the continuous, efficient, and safe operation of the large-capacity battery. In this embodiment, the sub-tube segment is set on a weak part. In some other embodiments, the sub-tube segment can be set in other positions on the upper cover plate.

[0182] The above-mentioned sub-tube section 10 preferably adopts a hollow pipe, the hollow structure inside the pipe is beneficial to reduce the overall weight and can be used as a shared channel; and the hollow pipe can be sealed at both ends, and a hole 19 is formed in the hollow pipe and the upper cover plate 1 to communicate with each other. In this way, the hollow cavity of the hollow pipe can be used as a gas storage cavity, and the gas generated inside the battery can be stored in the space to prevent swelling.

[0183] In addition, when the single battery 15 with the sub-tube section is constructed into a large-capacity battery, under the action of external force, the two closed ends of the hollow pipe can be opened, the cavities of all sub-tube sections are immediately communicated, and further communicated with the gas area in the cavities of all single batteries 15, and the gas in the cavities of each single battery 15 reaches balance. In this way, the differences between each single battery 15 can be effectively improved, the consistency of each single battery 15 in the charging and discharging process is ensured, the overall service life is prolonged, and the performance of the large-capacity battery is improved.

[0184] The above-mentioned under the action of external force generally means that a certain force is applied to the closed end by using a corresponding tool to make it break and form an opening.

[0185] As can be seen from Figure 10 to Figure 12 , the hollow pipe and the lower cover plate 3 are provided with holes 19 that communicate with each other, and the two ends of the hollow pipe are closed ends (in this embodiment, the two ends of the hollow pipe located on both sides of the hole 19 in the axial direction of the hollow pipe are called the two ends of the hollow pipe); for the sake of description, in this embodiment, the closed ends of the two ends of the hollow pipe are defined as the first closed end and the second closed end.

[0186] It can be achieved in various ways, one feasible method is to set a sealing gasket or sealing plug in the hollow pipe or the end part, which effectively blocks the passage at both ends of the hollow pipe to form a closed end; in addition, an integrated sealing plate in the hollow pipe can also be used to achieve the purpose of closing the two ends of the hollow pipe.

[0187] In order to facilitate the connection of adjacent hollow pipes, this embodiment adopts a circular variable-diameter pipe, the outer diameter of the first closed end is larger than that of the second closed end, a third blind hole 18 extending in the axial direction is formed in the first closed end, and the second closed end extends out of the upper cover plate 1.

[0188] The second closed end of one of the two adjacent hollow pipes is inserted into the third blind hole 18 of the other hollow pipe and is fixed by heat melting to realize the connection of the two hollow pipes. The length of the second closed end extending out of the upper cover plate 1 and the hole depth of the third blind hole 18 can be adjusted to ensure that the two single batteries 15 are in close contact after connection.

[0189] Preferably, the third blind hole 18 of the present embodiment adopts a counterbore structure, and the stepped surface 261 of the counterbore is used to cooperate with the end surface of the second closed end of the hollow pipe. When the second closed end of the hollow pipe is inserted into the third blind hole 18, the stepped surface closely abuts against the end surface of the second closed end, and the hollow pipe is limited in the axial direction. This effectively prevents unnecessary displacement of the hollow pipe in the axial direction, thereby avoiding problems such as loose connection and poor contact caused by displacement, and ensuring that the large-capacity battery maintains a stable connection state between the single batteries 15 during long-term use.

[0190] When the sub-pipe segment is used, on the one hand, when multiple single batteries 15 are assembled, the adjacent single batteries 15 are stably connected by means of the sub-pipe segment, so that the stability of the single batteries 15 in the box is greatly improved, and the structure of the entire large-capacity battery presents better stability and durability.

[0191] On the other hand, although the two ends of the sub-pipe segment 10 are closed in the normal state, the two closed ends can be smoothly opened under the action of a specific external force. Once the closed end is opened, the inner cavities of all the sub-pipe segments are immediately connected, and further connected with the inner cavity gas area of all the single batteries 15.

[0192] Like the first embodiment, the upper cover plate 1 of the present embodiment also adopts a plastic material, and can be integrally formed with the sub-pipe segment 10 and the through groove 42 by using an injection molding process. The low-density characteristics of the plastic material have a significant effect on reducing the overall weight of the battery. At the same time, by virtue of the good plasticity of the plastic, the injection molding process can accurately control the size of the mold cavity during the injection molding process, so that the sub-pipe segment 10 can achieve high dimensional accuracy during molding, ensuring precise cooperation with other single batteries 15. Moreover, since it is integrally formed, there is no problem of cumulative dimensional deviation caused by the assembly process, ensuring the stability and consistency of the connection of the single batteries 15, which is conducive to improving the overall performance and quality stability of the large-capacity battery and reducing problems such as poor connection and abnormal battery operation caused by size mismatch. At the same time, after the sub-pipe segment 10 of one of the adjacent single batteries 15 is inserted into the third blind hole 18 of the sub-pipe segment of the other single battery 15, the two can be fixedly connected by means of hot melting. After the plastic is cooled and solidified after hot melting, the two are fused together to form a stable connection structure that can withstand a large mechanical stress. For example, when the large-capacity battery is subjected to external forces such as vibration, impact, and extrusion, the connection between the single batteries 15 is effectively prevented from loosening or disengaging, ensuring the structural integrity and electrical connection stability of the large-capacity battery under complex working conditions, thereby improving the safety and reliability of the large-capacity battery and prolonging its service life. In addition, the hot melting connection method has a relatively low precision requirement, and even with a certain degree of dimensional deviation, good connection can be achieved through hot melting, thereby reducing the precision control cost during the production process.

[0193] The integrally formed through groove 42 also avoids additional splicing gaps, ensuring the overall sealing of the upper cover plate 1 and effectively preventing external impurities from invading. In addition, the injection molding process is low in cost and high in efficiency, reducing the processing procedures and production cost, and achieving significant economic benefits in mass production.

[0194] As shown in FIG. 1, a single battery 15 with the upper cover assembly of the present embodiment includes a shell enclosed by the cylinder body 2, the lower cover plate 3, and the upper cover plate 1 described above. Except that the upper cover plate 1 is different from that of Embodiment 1, the remaining structures are the same as those of Embodiment 1, which will not be described here. Figure 13

[0195] Embodiment 3

[0196] Unlike the above embodiments, in order to further reduce the cost, the strength of each single battery 15 shell meets certain requirements in the present embodiment. In the present embodiment, it is not required that the strength of the shell meets the strength requirement of the shell in the thermal runaway stage, but only needs to meet the strength requirement of the shell in the formation stage and the normal charging and discharging process of the battery (correspondingly, the strength of the weak part provided thereon should also meet the strength requirement of the shell in the formation stage and the normal charging and discharging process of the battery). In the formation stage and the normal charging and discharging stage of the battery, the battery will undergo a series of chemical reactions and physical changes. During this process, a certain pressure and heat will be generated inside the battery, and the shell needs to have sufficient strength to withstand these pressure and heat to ensure the smooth progress of the formation process and the normal use of the battery.

[0197] It can be assumed that the strength of the above-mentioned shell is P, P1≤P≤P2; wherein P1 is the strength requirement of the shell in the formation stage and the normal charging and discharging stage of the battery; P2 is the strength requirement of the shell in the thermal runaway stage.

[0198] Under the premise of meeting the above strength requirements, in the present embodiment, the thickness of the shell (cylinder body 2, upper cover plate 1, and lower cover plate 3) is h, which is less than h0, wherein h0 is the thickness of the plastic shell of the conventional single battery 15; the thickness of the plastic shell of the conventional single battery 15 is usually 5-8 mm. The thickness of the shell of the present embodiment can be between 1-4 mm. By thinning the shell thickness of the conventional single battery 15 with a plastic shell, a better heat dissipation effect can be further achieved, and the battery energy density can also be improved. In addition, thinning the thickness of the plastic shell means using less plastic material, which helps to save material cost and provides economic advantages for mass production and application.

[0199] Embodiment 4

[0200] Unlike the above embodiments, in the present embodiment, a groove 45 is provided on the lower surface of the upper cover plate 1, and the area of the upper cover plate 1 corresponding to the groove bottom of the groove 45 serves as a weak part. ​

[0201] As shown in Figure 14 and Figure 15 , as shown in Figure 14 Taking the connecting piece in Embodiment 1 as an example, Figure 15 Taking the connecting piece in Embodiment 2 as an example.

[0202] The groove 45 in this embodiment extends along the x direction, similar to Embodiment 1, and is located between the two polarity terminals 11.

[0203] The depth and width of the groove 45 can be set according to specific needs, ensuring that the area of the upper cover plate 1 where the groove 45 is located can be opened under a set pressure.

[0204] However, it should also be noted that the depth and width of the groove 45 cannot be too large. If the size exceeds a reasonable range, the groove 45 part may be deformed due to insufficient strength when the battery does not have thermal runaway, thereby affecting the performance of the battery. Therefore, during the design stage, various stresses that the upper cover plate 1 bears during normal operation of the battery, including internal pressure, external vibration, etc., need to be considered comprehensively. By reasonably planning the corresponding size of the groove 45, the structure of the upper cover plate 1 can be ensured to be stable under normal working conditions, while ensuring that the groove 45 can reliably play a venting function when thermal runaway occurs.

[0205] Compared to the through slot 42 on the upper surface of the upper cover plate 1 in Embodiment 1, this embodiment can better maintain the flatness of the battery upper cover plate 1.

[0206] In addition, during normal operation of the single battery 15, the inner cavity of the groove 45 can serve as a gas storage cavity, and the gas generated inside the single battery 15 can be stored in this space, reducing the degree of swelling of the single battery 15 shell.

[0207] Embodiment 5

[0208] Unlike the above embodiments, this embodiment has a through hole 46 along the width direction of the upper cover plate 1, forming a weak part.

[0209] As shown in Figure 16 to Figure 20 , as shown in Figure 16 and Figure 17 Taking the connecting piece in Embodiment 1 as an example, Figure 18 to Figure 20 Taking the connecting piece in Embodiment 2 as an example, the sub-pipe segment 10 is located in the through hole 46.

[0210] This embodiment also uses a plastic upper cover plate 1, which can be integrally formed with the through hole 46 by injection molding process.

[0211] As can be seen from the figure, the through hole 46 in this embodiment penetrates the upper cover plate 1 along the width direction of the upper cover plate 1, and is located between the two polarity terminals 11 of the upper cover plate 1.

[0212] In some other embodiments, a through hole 46 along the length direction of the upper cover plate 1 can also be formed on the upper cover plate 1 to form a weak part.

[0213] The cross-sectional shape and size of the through hole 46 can be set according to specific needs to ensure that the area of the upper cover plate 1 where the bottom of the through hole 46 is located can be opened under a set pressure.

[0214] However, it should also be noted that the through hole 46 cannot be too large. If it exceeds a reasonable range, the through hole 46 part may be deformed due to insufficient strength when the battery does not have thermal runaway, thereby affecting the performance of the battery. Therefore, during the design stage, various stresses that the upper cover plate 1 needs to withstand during normal operation of the battery, including internal pressure, external vibration, etc., need to be comprehensively considered. By reasonably planning the corresponding size of the through hole 46, the structure of the upper cover plate 1 can be ensured to be stable under normal working conditions, while ensuring that the through hole 46 can reliably play a venting function when thermal runaway occurs.

[0215] Compared with the weak part in Embodiment 1, this embodiment can also better maintain the flatness of the battery upper cover plate 1.

[0216] Embodiment 6

[0217] This embodiment is a large-capacity battery, which includes a pressure-bearing shell 13 and 12 single batteries 15 arranged in the pressure-bearing shell 13 in the above-mentioned embodiments. In other embodiments, the number of single batteries 15 can be adjusted according to actual needs.

[0218] The structure is shown in Figure 21 to Figure 27 , Figure 22 and Figure 23 , which takes the single battery 15 shown in Figure 13 as an example. In adjacent single batteries 15, the first docking pipe 33 of one of the single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by heat melting. One end of the sub-pipe segment 10 of one of the single batteries 15 is inserted into the third blind hole 18 of the sub-pipe segment 10 of the other single battery 15 and connected by heat melting.

[0219] Figure 24 Taking the single battery 15 shown in Figure 2 as an example, in adjacent single batteries, the first docking pipe 33 of one of the single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by heat melting. The second docking pipe 27 of one of the single batteries 15 is inserted into the second blind hole 26 of the other single battery 15 and connected by heat melting.

[0220] Figure 25 Taking the single battery 15 shown in Figure 14The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting.

[0221] Figure 26 The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting. Figure 20 The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting.

[0222] Figure 27 The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting. Figure 17 The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting.

[0223] The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting.

[0224] The first connecting pipe 33 of one of the adjacent single batteries 15 is inserted into the first blind hole 31 of the other single battery 15 and connected by hot melting.

[0225] It should be noted that:

[0226] 1. To ensure that the inner cavity of each individual cell 15 in the large-capacity battery is not affected by the external environment, the second side wall area of ​​the lower cover plate enclosed by the first connecting pipe 33 of one of the two outermost individual cells 15 of the large-capacity battery does not need to be opened, and the opening of the first blind hole 31 of the other outermost individual cell 15 also needs to be sealed.

[0227] 2. In order to improve the regularity of the entire large-capacity battery structure, in this embodiment, the outermost single cell 15 can be cut off to expose the first pair of connecting pipes 33 that do not need to be connected. After cutting off, it is necessary to ensure the sealing of the casing of the single cell 15.

[0228] In this embodiment, the aforementioned tool is used to open the bottom 262 of the second blind hole of each individual battery cell 15 and the separator 210 (or the closed end of the sub-tube segment 10), so that the inner cavity of all the second blind holes 26 and the inner cavity of the second connecting pipe 27 are connected (or the inner cavity of all the sub-tube segments 10 are connected), and further connected with the gas region inside the cavity of all individual batteries 15, so that the gas inside the cavity of all individual batteries 15 is balanced, thereby obtaining a large-capacity battery. Based on the gas connection, the differences that may originally exist between individual batteries 15 are improved, ensuring the consistency of each individual battery 15 during the charging and discharging process, extending the overall service life, and improving the performance of the large-capacity battery.

[0229] against Figure 24 , Figure 25 and Figure 27 Specifically, the structure shown can be opened by the following process: insert a tool into the second blind hole 262 of one of the outermost single cells 15 along the x-direction and apply a pushing force to open the second blind hole bottom 262 and the separator 210 of each single cell 15.

[0230] It should be noted that:

[0231] 1. To ensure that the inner cavity of each individual cell 15 in the large-capacity battery is not affected by the external environment, one of the two outermost individual cells 15 of the large-capacity battery does not need to be opened, and the opening of the second blind hole 26 of the other outermost individual cell 15 also needs to be sealed.

[0232] 2. In order to improve the regularity of the entire large-capacity battery structure, in this embodiment, the outermost single cell 15 can be cut off to expose the second pair of connecting pipes 27 that do not need to be connected. After cutting off, it is necessary to ensure the sealing of the casing of the single cell 15.

[0233] against Figure 23 and Figure 26As shown in the structure, the closed end of the sub-tube segment of each monomer battery 15 can be opened by the following process: along the x direction, a tool is inserted into the third blind hole of one of the outermost monomer batteries 15, and a pushing force is applied to open the closed end of the sub-tube segment of each monomer battery 15.

[0234] It should be noted that:

[0235] In order to ensure that the internal cavity of each monomer battery 15 in the large-capacity battery is not affected by the external environment, the closed end of one of the sub-tube segments in the two outermost monomer batteries 15 of the large-capacity battery does not need to be opened, and at the same time, the opening part of the third blind hole 18 of the other outermost monomer battery 15 needs to be sealed.

[0236] When the top of each monomer battery 15 has a weak part, a pressure relief channel is formed between the weak part of each monomer battery 15 and the pressure-bearing shell 13;

[0237] Figure 23 And Figure 24 In the above, the weak part is a through slot 42, and the through slots 42 of each monomer battery 15 are connected (or spliced), thereby forming a pressure relief channel between the weak part of each monomer battery 15 and the pressure-bearing shell 13. A channel can also be provided on the pressure-bearing shell 13, which covers the through slots 42 of each monomer battery 15 and forms a pressure relief channel with the through slots 42 of each monomer battery 15.

[0238] Figure 25 In the above, the weak part is a groove 45 formed in the lower surface of the upper cover plate, and a channel needs to be provided on the pressure-bearing shell 13, which covers the weak part of each monomer battery 15 (the area of the upper cover plate 1 corresponding to the groove bottom) and forms a pressure relief channel between the weak part of each monomer battery 15.

[0239] Figure 26 And Figure 27 In the above, the weak part is a through hole 46 formed in the upper cover plate, and the through holes 46 of each monomer battery 15 are connected, thereby forming a pressure relief channel, which is also located between the weak part (the hole bottom of the through hole 46) and the pressure-bearing shell 13.

[0240] As Figure 21 shown, the pressure-bearing shell 13 is provided with a pressure relief part 16 corresponding to the pressure relief channel (the pressure relief part 16 here can also be called an explosion-proof part, an explosion-proof opening, or a pressure relief opening, etc., which is usually provided with a pressure relief valve or a pressure relief membrane, etc.), and when the monomer battery 15 is in thermal runaway, the thermal runaway smoke breaks through the weak part, passes through the pressure relief channel, breaks through the pressure relief part 16, and is discharged from the pressure-bearing shell 13.

[0241] In the initial stage of thermal runaway, the thermal runaway smoke can be orderly discharged through the pressure relief channel, effectively preventing the spread to the large-capacity battery shell, thereby preventing the further deterioration of the thermal runaway condition.

[0242] The strength of the pressure shell 13 needs to meet the strength requirements of the shell in the thermal runaway stage, that is, the pressure shell 13 has good strength. Such design not only can effectively resist the high pressure impact of thermal runaway by the reinforced outer packaging box, greatly improving the overall safety of the large capacity battery; especially when plastic material is used as the shell of the internal single battery 15, the pressure shell 13 can form a solid thermal barrier, even in the extreme case of single battery 15 shell melting, it can effectively isolate high temperature flame and harmful gas, prevent the spread of thermal runaway, and improve the safety of large capacity battery after thermal runaway. In addition, when plastic material is used as the shell of the internal single battery 15, a barrier film can be provided between each single battery 15 and the pressure shell 13 to prevent the electrolyte in each single battery 15 from permeating outward.

[0243] Compared with other materials, the metal material pressure shell 13 is more reliable in the face of emergency situations such as thermal runaway. It can withstand greater impact force and destructive force, reduce the possibility of accidents, and protect the safety of personnel and surrounding equipment. The pressure shell 13 of the present embodiment does not directly contact the electrolyte, so it can be selected as an iron shell, a steel shell or a stainless steel shell; the iron shell has certain strength and cost advantages, and can be selected in some scenes that are more sensitive to cost and do not have particularly high strength requirements. The steel shell has relatively high strength and can provide more reliable protection for the battery, which is suitable for applications with high safety and structural strength requirements. The stainless steel shell not only has good strength performance, but also has excellent corrosion resistance, which makes it perform well in some battery application scenarios that may face humid and corrosive environments, effectively prolonging the service life of the battery and ensuring the stable operation of the battery in complex environments.

[0244] As shown in Figure 28 and Figure 29 , taking the single battery 15 shown in Figure 13 as an example, the present embodiment can also have an avoidance hole 17 corresponding to the polarity terminal 11 of each single battery 15 on the top plate of the pressure shell 13; each single battery 15 polarity terminal 11 extends out of the avoidance hole 17; the top plate area of the pressure shell 13 corresponding to the avoidance hole 17 is fixed and sealed with the single battery 15 shell.

[0245] In order to optimize the heat dissipation performance of the large capacity battery, the heat exchange member 14 is additionally arranged on the basis of the large capacity battery to exchange heat with the polar terminal 11. The polar terminal 11 is a key part for connecting the inside and outside of the battery. During the charging and discharging process, the current enters and exits the battery through the polar terminal 11. When heat is generated inside the battery, the heat dissipation through the polar terminal 11 can provide a relatively direct heat conduction path. The heat can be quickly conducted from the inside of the battery to the polar terminal 11, and then dissipated to the external environment by the polar terminal 11. In addition, the polar terminal 11 is usually located at the positive and negative poles of the battery, and during the charging and discharging process, the positive and negative poles are often the areas where heat is generated more concentratedly. By dissipating heat from the polar terminal 11, the temperature of these key parts can be more effectively reduced.

[0246] The heat exchange member can be a heat transfer pipe; the polar terminal 11 of each single battery 15 is provided with a through slot or a through hole for mounting the heat transfer pipe; the heat transfer pipe is fixed in the through slot or the through hole of the polar terminal 11 of each single battery 15. The heat generated inside the battery is conducted to the heat transfer pipe through the heat transfer pipe on the polar terminal 11, and then dissipated by the heat transfer pipe, so as to achieve heat dissipation of the battery.

[0247] The heat exchange member can also be a heat exchange device, which is arranged at the top of each single battery 15; the polar terminal 11 penetrates the heat exchange device, and at least part of the structure of the polar terminal 11 is located in the inner cavity of the heat exchange device and directly contacts with the heat exchange medium; another part of the structure of the polar terminal 11 is located outside the heat exchange device as an electrical connection part; the side wall of the polar terminal 11 is sealed with the heat exchange device. By directly placing part of the structure of the polar terminal 11 in the heat exchange medium flow cavity (the inner cavity of the heat exchange device), the polar terminal 11 directly contacts with the heat exchange medium, the heat exchange of the polar terminal 11 is realized, the heat exchange path is short, the heat exchange medium directly acts on the polar terminal 11, the utilization efficiency of the heat exchange medium is improved, and the heat exchange efficiency of the battery is improved.

[0248] In addition, an insulating sealing adhesive layer can be arranged between each single battery 15 and between each single battery 15 and the pressure-bearing shell 13. The insulating sealing adhesive layer is mainly laid in the space between each single battery 15 and the pressure-bearing shell 13, and the heat exchange member part in the pressure-bearing shell 13 is located in the insulating sealing adhesive layer; when there is a gap between each single battery 15, the insulating sealing adhesive liquid can also penetrate into the gap to form an insulating sealing adhesive layer.

[0249] It should be noted that the insulating sealing adhesive layer is not arranged in the explosion vent channel.

[0250] In the embodiment, the insulating sealing adhesive layer has at least the following advantages:

[0251] I. Anti-condensation;

[0252] During long-term use, condensation will be generated on the surface due to the temperature difference between the inside and outside of the heat exchange component. When the condensation accumulates to a certain amount, it may cause short circuit problems. By laying an insulating sealant layer, the heat exchange component is entirely wrapped. When condensation is generated on the surface of the heat exchange component, under the protection of the insulating sealant layer, the battery short circuit can be prevented.

[0253] II. Further improve the stability of each monomer battery 15 in the pressure shell 13;

[0254] The insulating sealant liquid seeps into each gap between each monomer battery 15 and between each monomer battery 15 and the pressure shell 13, which can further improve the stability of each monomer battery 15 in the pressure shell 13.

[0255] When the structure shown in Figure 28 and Figure 29 is used, an insulating sealant layer can also be laid on the top plate of the pressure shell 13, and the heat exchange component is located in the insulating sealant layer. When condensation is generated on the surface of the heat exchange component, under the protection of the insulating sealant layer, the battery short circuit can be prevented.

Claims

1. A case for a single battery, characterized by: The upper cover plate, the cylinder and the lower cover plate are all made of plastic material; In the height direction, the inner cavity of the shell is divided into an electrode assembly support area and an electrode assembly containing area from bottom to top; A first recess and a first protrusion are arranged on the shell area corresponding to the electrode assembly support area; the first recess is used for embedding and fixedly connecting the first protrusion on the shell of another single battery; under the action of external force, a channel can be opened in the first recess and the first protrusion, and the channel is in communication with the electrolyte area in the inner cavity of the single battery shell. The upper cover plate is provided with a connecting piece for connecting with the connecting piece on the adjacent single battery, and under the action of external force, a channel can be opened in the connecting piece, and the channel is in communication with the gas area in the inner cavity of the single battery shell.

2. The case for a single cell according to claim 1, characterized by: The connecting piece is a second recess and a second protrusion arranged on the opposite side walls of the upper cover plate; the second recess is used for embedding and fixedly connecting the second protrusion of another single battery, and under the action of external force, a channel can be opened in the second protrusion and the second recess, and the channel is in communication with the gas area in the inner cavity of the single battery shell.

3. The case for a single cell according to claim 2, characterized by: The second recess is a second blind hole opened in the first side wall of the upper cover plate; the second protrusion is a second butt joint pipe arranged on the outer wall of the second side wall of the upper cover plate; the second butt joint pipe is used for embedding in the second blind hole of another single battery and fixedly connected; the first side wall of the upper cover plate and the second side wall of the upper cover plate are parallel to each other.

4. The case for a single cell according to claim 3, characterized by: A channel in communication with the inner cavity of the second butt joint pipe is opened on the upper cover plate; a partition plate is arranged in the channel, and a cavity is formed between the partition plate and the bottom end of the second blind hole; a through hole is arranged in the area of the upper cover plate corresponding to the cavity, and the through hole is in communication with the inner cavity of the single battery; Under the action of external force, the partition plate and the bottom end of the second blind hole can be opened, so that the inner cavities of the second butt joint pipe, the channel and the second blind hole are all in communication with the inner cavity of the single battery.

5. The case for a single cell according to claim 1, characterized by: The connecting piece is a sub-pipe segment arranged on the upper surface of the upper cover plate; the sub-pipe segment is a hollow pipe; the hollow pipe and the upper cover plate are provided with openings in communication with each other; the two ends of the hollow pipe are closed ends; The two closed ends are defined as a first closed end and a second closed end; a third blind hole extending in the axial direction is opened in the first closed end; the third blind hole is used for inserting and fixedly connecting the second closed end of the hollow pipe of another single battery; under the action of external force, the first closed end and the second closed end of the hollow pipe can be opened.

6. The case for a single cell according to any one of claims 1 to 5, characterized by: The first recess is a first blind hole opened in the first side wall of the lower cover plate; the first protrusion is a first butt joint pipe arranged on the outer wall of the second side wall of the lower cover plate; the first butt joint pipe is used for embedding in the first blind hole of another single battery and fixedly connected; the first side wall of the lower cover plate and the second side wall of the lower cover plate are parallel to each other.

7. The case for a single cell according to claim 6, characterized by: The inner surface of the lower cover plate is provided with a plurality of bosses arranged in an array; the top of the boss is used for supporting the electrode assembly, and the gap between the bosses serves as an electrolyte flow channel.

8. The case for a single cell according to claim 7, characterized by: Under the action of external force, the second side wall area of the lower cover plate circumscribed by the bottom end of the first blind hole and the first butt joint pipe can be opened and in communication with the electrolyte flow channel.

9. The case for a single cell according to Claim 1, wherein: The upper cover plate is integrally provided with a weak part; the strength of the weak part is less than that of the rest of the upper cover plate; when the single battery is in thermal runaway, the thermal runaway flue gas breaks through the weak part and is discharged.

10. The case for a single battery cell according to claim 1, characterized by: The first recess and the first protrusion are both integrated with the cylinder or the lower cover plate; the first recess is used for embedding the first protrusion of another single battery and is fixedly connected through a hot melting mode; the connecting piece is integrated with the upper cover plate; and the connecting piece is used for fixedly connecting the connecting piece of another single battery through a hot melting mode.

11. A monobloc battery characterized by: The shell for the single battery includes the shell for the single battery according to any one of claims 1 to 10.

12. The cell according to claim 11, wherein: The shell strength is P, P1≤P≤P2; wherein P1 is the strength requirement of the shell in the formation stage and the normal charging and discharging stage of the battery; and P2 is the strength requirement of the shell in the thermal runaway stage.

13. A high capacity battery characterized by: The shell for the single battery includes the shell for the single battery according to any one of claims 1 to 10. In the adjacent single batteries, the first protrusion of one single battery is embedded in the first recess of another single battery and is fixedly connected, and the first protrusion and the first recess are provided with a channel through the electrolyte area in the single battery shell; and the connecting piece of one single battery is fixedly connected with the connecting piece of another single battery, and the connecting piece is provided with a channel through the gas area in the single battery shell. The strength of the pressure-bearing shell meets the strength requirement of the shell in the thermal runaway stage, and the pressure-bearing shell is provided with a pressure relief part.

14. The battery of claim 13, wherein: The pressure relief channel is formed between the weak part of each single battery and the pressure-bearing shell. The pressure-bearing shell is provided with a pressure relief part corresponding to the pressure relief channel; when the single battery is in thermal runaway, the thermal runaway flue gas breaks through the weak part, passes through the pressure relief channel, breaks through the pressure relief part and is discharged out of the pressure-bearing shell.

15. The high capacity battery of claim 13, wherein: The top plate of the pressure-bearing shell is provided with a avoiding hole corresponding to the polarity terminal of each single battery; the polarity terminal of each single battery extends out of the avoiding hole; and the region of the top plate of the pressure-bearing shell corresponding to the avoiding hole is fixedly sealed with the single battery shell.

16. The high capacity battery of claim 13, wherein: The heat exchange member is further included, and the heat exchange member exchanges heat with the polarity terminal. The heat exchange member is further included, and the heat exchange member exchanges heat with the polarity terminal.

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