Pressure relief cylindrical capacitor cell

Abstract

The application discloses a cylindrical capacitor monomer with pressure relief, which comprises an electric core inserted in a shell, a negative electrode cover plate assembly connected with the electric core top through a negative electrode current collector, and a positive electrode cover plate connected with the electric core bottom through a positive electrode current collector; a boss in the center of the positive electrode current collector passes through a center hole of the positive electrode cover plate, a liquid injection hole is formed in the boss, and a rubber plug and an aluminum plug are inserted in the liquid injection hole; a pressure relief hole is formed in the positive electrode cover plate, and an explosion-proof valve is arranged in the pressure relief hole; a plurality of convex ribs are arranged on the lower side of the positive electrode current collector, and a plurality of lower concave cavities are arranged on the upper side of the positive electrode current collector. The pressure relief structure of the application is arranged at the bottom of the positive electrode end of the monomer, and adopts a lower exhaust mode to relieve pressure, thereby reducing the assembly difficulty, improving the assembly precision, improving the exhaust pressure relief performance and capacity density of the monomer, and also making the overall size of the module smaller, reducing the requirement on the installation space, and making the overall structure more compact.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy element, and particularly relates to a pressure relief type cylindrical capacitor monomer. BACKGROUND

[0002] The energy storage element includes but is not limited to supercapacitors, hybrid supercapacitors, hybrid battery capacitors and / or other capacitor and / or battery elements (e.g., lithium ion, lead-acid, nickel-cadmium, sodium ion, and / or others). The energy storage element is widely used in vehicles, electronic products and energy storage systems, transportation, smart grid and industrial energy saving and consumption reduction, etc. The energy storage element technology is an important factor for the development.

[0003] The capacitor monomer as a kind of energy storage element is usually composed of a shell, an electric core, an electrolyte, a cover plate, a current collector, a pole, etc. After a plurality of capacitor monomers are connected in series or in parallel and are inserted into a support, a capacitor module is formed. The capacitor module has superior characteristics such as high efficiency, high current capacity, wide voltage range, wide temperature range, long service life, long working life, maintenance-free, simple integration, low cost, etc., and has a broad development prospect.

[0004] The capacitor cell inevitably generates heat during operation, which increases the internal pressure or temperature of the cell. In order to timely vent and release pressure when the internal pressure or temperature reaches a threshold, a pressure relief structure is usually provided on the capacitor cell. The existing cylindrical capacitor cell usually has an exhaust hole on the negative cover plate at the upper end, and an explosion-proof valve is provided on the exhaust hole as a pressure relief structure. However, this upper pressure relief type cylindrical capacitor cell has the following problems: (1) When the capacitor cell is connected in series / parallel to form a capacitor module, the negative terminal (top end) of the capacitor cell needs to be connected by leading out from the negative terminal. Since the negative cover plate has an exhaust hole, in order to avoid blocking or interfering with the exhaust hole, the leading-out components and connecting components need to avoid the exhaust hole of the negative cover plate during installation and connection, which requires higher requirements for the installation position and angle of the capacitor cell, the leading-out components and the connecting components, increases the assembly difficulty, and the assembly and welding reference between the components are not easy to find and unify, which is prone to large assembly errors and low assembly precision; (2) When the module is formed, the connection structure of the top negative lead-out end needs to avoid the exhaust hole, and enough space for exhaust and pressure relief is needed between the connection structures of the module, which determines that the space size of the top end of the module cannot be too small. The space occupied by the connection part at the top end of the module is large, so the space for accommodating the capacitor cell is compressed, and the capacitor cell needs to be designed as compact as possible, so the space for exhaust and electrolyte in the capacitor cell is not too large, which reduces the exhaust and pressure relief performance and energy density of the capacitor cell. In order to increase the energy density, the overall size of the capacitor cell is enlarged, which makes the overall size of the module very large, requires high installation space, and the overall structure is not compact enough. SUMMARY

[0005] In view of the above-mentioned shortcomings of the existing upper pressure relief type capacitor cell, the present applicant provides a lower pressure relief type cylindrical capacitor cell with a reasonable structure. The pressure relief structure is arranged at the bottom end, the exhaust space and electrolyte space in the cell are larger, the assembly difficulty when forming a module is reduced, the assembly error is reduced, and the assembly precision is improved.

[0006] The technical scheme adopted by the present application is as follows:

[0007] A lower pressure relief type cylindrical capacitor cell includes a shell in which an electric core is inserted and arranged, the electric core is connected to a negative cover plate assembly through a negative current collector at the top, and the electric core is connected to a positive cover plate through a positive current collector at the bottom. A boss in the center of the positive current collector passes through the center hole of the positive cover plate, an injection hole is formed in the boss, a rubber plug and an aluminum plug are inserted in the injection hole, a pressure relief hole is formed in the positive cover plate, and an explosion-proof valve is arranged in the pressure relief hole. A plurality of convex ribs are arranged on the lower side of the positive current collector, and a plurality of lower concave cavities are arranged on the upper side of the positive current collector.

[0008] As a further improvement of the above technical scheme:

[0009] The through holes are arranged on the convex ribs, and the positions of the through holes of all the convex ribs are located in the same annular region with the center of the positive current collector disc as the center.

[0010] The convex rib is radially arranged on the positive current collector disc, and the convex rib is concavely formed downward from the plate surface of the positive current collector disc, and a concave cavity is formed on the upper side of the convex rib, and the concave cavity constitutes the concave cavity.

[0011] The convex rib is radially arranged on the positive current collector disc, and the convex rib is concavely formed downward from the plate surface of the positive current collector disc, and a concave cavity is formed on the upper side of the convex rib, and the concave cavity constitutes the concave cavity.

[0012] The convex rib is radially arranged on the positive current collector disc, and the convex rib is concavely formed downward from the plate surface of the positive current collector disc, and a concave cavity is formed on the upper side of the convex rib, and the concave cavity constitutes the concave cavity.

[0013] The outer peripheral edge of the positive current collector disc is provided with a plurality of bending pieces, and the height of the bending piece is equivalent to the height of the convex rib.

[0014] The negative cover plate assembly comprises an upper cover plate, an adapter plate, a negative post head and a connecting column, the adapter plate, the upper cover plate and the negative post head are sequentially sleeved on the connecting column, the upper cover plate is welded and fixed on the shell, and the adapter plate is welded with the negative current collector disc.

[0015] Insulating pieces are arranged between the upper cover plate and the adapter plate, the negative post head and the connecting column.

[0016] The negative post head is made of aluminum, and the connecting column is made of copper.

[0017] The negative cover plate assembly is fixedly connected to the top end of the shell, and the positive cover plate is fixedly connected to the bottom end of the shell.

[0018] The beneficial effects of the present application are as follows:

[0019] (1) The pressure relief structure of the application is arranged at the bottom of the single positive electrode end, and adopts a lower exhaust mode for pressure relief. On the one hand, since the pressure relief structure is arranged at the positive electrode end, it is not necessary to arrange a pressure relief structure at the negative electrode end (top end), so that the lead-out component and the connecting structure at the negative electrode end do not need to be avoided during installation and connection, which reduces the requirements for the installation position and angle of the capacitor single lead-out component and the connecting component, and the position and angle of each component are more flexible, the assembly difficulty is reduced, the assembly and welding reference between each component is better and easier to unify, and the assembly error is reduced, the assembly precision is improved. On the other hand, since the connecting structure at the negative electrode end does not need to avoid the exhaust hole, the connecting structures between the modules can be designed more compactly, thereby reducing the occupied space at the top end of the module, increasing the accommodation space of the capacitor single, and allowing the capacitor single to have a larger design space, so that the capacitor single can have a larger space for exhaust and electrolyte, thereby improving the exhaust pressure relief performance and energy density of the single. Moreover, under the condition of obtaining higher energy density, the overall size of the module can be smaller, the requirement for the installation space is reduced, and the overall structure is more compact. The injection hole and the pressure relief hole are arranged at the bottom and located at the positive electrode end, which can avoid pollution of the electrolyte.

[0020] (2) The application sets the protruding ribs at the lower side of the positive current collecting disc and sets the lower concave cavity at the upper side, effectively utilizes the space between the bottom of the electric core and the positive cover plate, increases the exhaust space and area, and also increases the space of the electrolyte, thereby improving the space utilization rate in the shell, the pressure relief and exhaust performance, and the energy density. The protruding ribs serve as reinforcing ribs, which can improve the strength of the positive current collecting disc, prevent deformation of the positive current collecting disc, and ensure the power transmission performance.

[0021] (3) The protruding ribs of the positive current collecting disc of the application are arranged in the circular ring area opposite to the pressure relief hole, which can give the exhaust of the pressure relief hole a position and ensure smooth pressure relief and exhaust. When the positive cover plate is installed, no matter at which angle the pressure relief hole is installed, it will not be interfered by the protruding ribs, which eliminates the limitation on the installation angle of the pressure relief hole, makes the installation of the positive cover plate more flexible, and reduces the assembly difficulty. The hole also provides a flow channel for the electrolyte, which is more conducive to the flow and distribution of the electrolyte to each part in the shell, improves the uniformity of the electrolyte distribution, and improves the energy density. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the exploded view of the application.

[0023] Figure 2 is the longitudinal sectional view of the application.

[0024] Figure 3 is Figure 2 is the enlarged view of the middle A part.

[0025] Figure 4 isFigure 2 Enlarged view of middle B part.

[0026] Figure 5 Perspective view from top view angle of positive current collector.

[0027] Figure 6 Perspective view from top view angle of positive current collector.

[0028] In the figure: 1, shell; 2, electric core; 3, negative current collector;

[0029] 4, negative cover plate assembly; 41, upper cover plate; 42, adapter plate; 43, negative post head; 44, connecting post; 45, first insulating piece; 46, second insulating piece; 47, third insulating piece;

[0030] 5, positive current collector; 51, boss; 52, liquid injection hole; 53, concave cavity; 54, convex rib; 55, groove; 56, opening; 57, circular ring area; 58, bending piece;

[0031] 6, positive cover plate; 61, center hole; 62, pressure relief hole;

[0032] 7, explosion-proof valve piece; 8, rubber plug; 9, aluminum plug. DETAILED DESCRIPTION

[0033] The specific embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0034] As shown in Figure 1 , Figure 2 , the electric core 2 is inserted in the shell 1 of the present application, the top of the electric core 2 is connected with the negative current collector 3, the negative current collector 3 is connected with the negative cover plate assembly 4, and the negative cover plate assembly 4 is fixedly connected to the top end of the shell 1; the bottom of the electric core 2 is connected with the positive current collector 5, the positive current collector 5 is connected with the positive cover plate 6, and the positive cover plate 6 is fixedly connected to the bottom end of the shell 1.

[0035] As shown in Figure 1 , Figure 2 , Figure 4As shown, the bottom surface of the positive current collector 5 is centrally provided with a boss 51 protruding downward, and the positive cover plate 6 is provided with a central hole 61, and the boss 51 of the positive current collector 5 penetrates the central hole 61 of the positive cover plate 6 and is fixed by welding. The boss 51 of the positive current collector 5 is centrally provided with a liquid injection hole 52, and the liquid injection hole 52 is sequentially inserted with a rubber plug 8 and an aluminum plug 9 from top to bottom. The positive cover plate 6 is provided with a pressure relief hole 62 outside the central hole 61, and the pressure relief hole 62 is provided with an explosion-proof valve plate 7, and when the internal pressure or temperature of the single cell reaches a threshold value, the exhaust pressure relief is carried out through the pressure relief hole 62. The pressure relief structure of the present application is arranged at the bottom of the positive electrode end of the single cell, and the exhaust is carried out in a downward manner. On the one hand, since the pressure relief structure is arranged at the positive electrode end, it is not necessary to arrange a pressure relief structure at the negative electrode end (top end), so that the lead-out components and the connecting structure at the negative electrode end do not need to be avoided during installation and connection, thereby reducing the requirements for the installation position and angle of the capacitor single cell lead-out components and the connecting components, and the position and angle of each component are more flexible, the assembly difficulty is reduced, and the assembly and welding reference between each component is better and easier to unify, which is more conducive to reducing assembly error and improving assembly precision. On the other hand, since the connecting structure at the negative electrode end does not need to avoid the exhaust hole, the connecting structures between the modules can be designed more compactly, thereby reducing the occupied space at the top end of the module, increasing the accommodation space of the capacitor single cell, and allowing the capacitor single cell to have a larger design space, so that the capacitor single cell can have a larger space for exhaust and electrolyte, thereby improving the exhaust pressure relief performance and capacity density of the single cell. Moreover, under the condition of obtaining higher energy density, the overall size of the module can be smaller, the requirement for installation space is reduced, and the overall structure is more compact. The liquid injection hole 52 and the pressure relief hole 62 are arranged at the bottom and at the positive electrode end, which can avoid pollution of the electrolyte.

[0036] As Figure 5 、 Figure 6As shown, the boss 51 of the positive current collector 5 is concave downward from the plate surface of the positive current collector 5, so that a concave cavity 53 is formed on the upper side of the boss 51. A plurality of radial ribs 54 are arranged on the bottom surface of the positive current collector 5 and protrude downward from the outer side of the boss 51, the inner side of the rib 54 is connected with the boss 51, and the outer side extends to the outer edge of the positive current collector 5; the rib 54 is also concave downward from the plate surface of the positive current collector 5, so that a concave groove 55 is formed on the upper side of the rib 54, and the groove 55 is connected with the central cavity 53. The rib 54 acts as a reinforcing rib, which can improve the strength of the positive current collector 5, prevent the positive current collector 5 from deforming, and ensure the power transmission performance; moreover, the rib 54 is protruded downward, which blocks between the positive current collector 5 and the positive cover plate 6, so that the space between the positive current collector 5 and the adjacent rib 54 on the lower side of the positive current collector 5 can be used for exhaust, which increases the exhaust space and area; the groove 55 on the upper side of the boss 51 and the cavity 53 on the upper side of the rib 54 are both concave cavities, which provide space for the electrolyte in the single cell, and increase the space for containing the electrolyte; that is, by arranging the rib 54 on the lower side of the positive current collector 5 and the concave cavity on the upper side of the positive current collector 5, the space between the bottom of the single cell 2 and the positive cover plate 6 is effectively utilized, which increases the exhaust space and area, and also increases the space for the electrolyte, improves the space utilization in the shell 1, and improves the pressure relief and exhaust performance and energy density. The rib 54 is provided with a through opening 56, and the positions of the openings 56 of all the ribs 54 are located in the same circular region 57 with the center of the positive current collector 5 as the center, as shown in Figure 2 、 Figure 4 As shown, the radial position of the pressure relief hole 62 of the positive cover plate 6 corresponds to the position of the circular region 57, and the pressure relief hole 62 directly faces the circular region 57. Since the rib 54 is protruded downward on the positive current collector 5, the opening 56 is arranged in the circular region 57 directly facing the pressure relief hole 62, which gives the pressure relief hole 62 a position for exhaust, ensures smooth pressure relief and exhaust, and the position of the opening 56 of each rib 54 is located in the circular region 57, so that when the positive cover plate 6 is installed, no matter which angle the pressure relief hole 62 is rotated to, the positive cover plate 6 will not be interfered by the rib 54, which eliminates the limitation on the installation angle of the pressure relief hole 62, makes the installation of the positive cover plate 6 more flexible, and reduces the assembly difficulty; the opening 56 also provides a flow channel for the electrolyte, which is more conducive to the flow and distribution of the electrolyte to all parts of the shell 1, improves the uniformity of the electrolyte distribution, and improves the energy density. As shown in Figure 5 、 Figure 6 As shown, the outer peripheral edge of the positive current collector 5 is bent axially downward to form a plurality of bent pieces 58, and the height of the bent piece 58 is equivalent to the height of the rib 54. The bent piece 58 can further improve the strength of the positive current collector 5, and the bent piece 58 can also play a limiting role to ensure the electrolyte space and have the maximum contact area with the electrolyte.

[0037] As shown in Figure 2 、 Figure 3As shown, the negative cover plate assembly 4 includes an upper cover plate 41, an adapter plate 42, a negative post head 43 and a connecting post 44. The adapter plate 42, the upper cover plate 41 and the negative post head 43 are sequentially sleeved on the connecting post 44 from bottom to top. The upper cover plate 41 is welded and fixed on the shell 1, and the adapter plate 42 is welded with the negative current collector 3. The upper cover plate 41, the adapter plate 42, the negative post head 43 and the connecting post 44 are respectively insulated by corresponding insulating pieces. The first insulating piece 45 is arranged between the upper cover plate 41 and the negative post head 43 and the connecting post 44. The second insulating piece 46 is arranged between the bottom surface of the upper cover plate 41 and the corresponding stepped surface of the connecting post 44. The third insulating piece 47 is arranged between the upper cover plate 41 and the adapter plate 42. The connecting post 44 is made of copper post, which is in contact with the electrolyte in the single body to conduct electricity, has good conductivity and will not be electrochemically corroded. The negative post head 43 is made of aluminum piece, which has good welding performance, is more conducive to welding with other single bodies of the module by using aluminum sheet, and has lower price and better economy.

[0038] The above description is an explanation of the present application, not a limitation of the present application. The present application can be modified in any form without departing from the spirit of the present application.

Claims

1. A single cylindrical capacitor with a downward discharge capability, comprising a housing (1) in which a battery cell (2) is inserted, the top of the battery cell (2) being connected to a negative electrode cover plate assembly (4) via a negative electrode current collector (3), and the bottom of the battery cell (2) being connected to a positive electrode cover plate (6) via a positive electrode current collector (5); characterized in that: The boss (51) in the center of the positive electrode current collector (5) protrudes from the central hole (61) of the positive electrode cover plate (6). A liquid injection hole (52) is provided on the boss (51). A rubber plug (8) and an aluminum plug (9) are inserted into the liquid injection hole (52) from top to bottom. A pressure relief hole (62) is provided on the positive electrode cover plate (6). An explosion-proof valve plate (7) is installed in the pressure relief hole (62). Several ribs (54) are provided on the lower side of the positive electrode current collector (5). The ribs (54) protrude downward and block the positive electrode current collector (5) and the positive electrode cover plate (6). Between 6), several recessed cavities are provided on the upper side of the positive electrode current collector (5); several through holes (56) are provided on several protruding ribs (54), and the positions of the holes (56) of all the protruding ribs (54) are located in the same annular area (57) with the center of the positive electrode current collector (5) as the center; the annular area (57) is directly opposite the pressure relief hole (62) of the positive electrode cover plate (6); several bent pieces (58) are provided on the outer periphery of the positive electrode current collector (5), and the height of the bent pieces (58) is equivalent to the height of the protruding ribs (54); The negative electrode cover plate assembly (4) includes an upper cover plate (41), a transition plate (42), a negative electrode post (43), and a connecting post (44). Insulating elements are respectively provided between the upper cover plate (41), the transition plate (42), the negative electrode post (43), and the connecting post (44). A first insulating element (45) is provided between the upper cover plate (41), the negative electrode post (43), and the connecting post (44). A second insulating element (46) is provided between the bottom surface of the upper cover plate (41) and the corresponding step surface of the connecting post (44). A third insulating element (47) is provided between the upper cover plate (41) and the transition plate (42).

2. The single-cell, downward-draining cylindrical capacitor according to claim 1, characterized in that: The boss (51) of the positive current collector (5) is formed downward from its plate surface, and a cavity (53) is formed on the upper side of the boss (51), the cavity (53) constitutes the recessed cavity.

3. The single-cell, downward-draining cylindrical capacitor according to claim 1, characterized in that: The ribs (54) of the positive current collector (5) are arranged radially. The ribs (54) are formed by downward indentation from the plate surface of the positive current collector (5). A groove (55) is formed on the upper side of the ribs (54). The groove (55) constitutes the recessed cavity.

4. The single-cell, downward-draining cylindrical capacitor according to claim 3, characterized in that: The inner side of the rib (54) is connected to the boss (51), and the outer side extends to the outer edge of the positive current collector (5). The groove (55) is connected to the central cavity (53).

5. The single-cell, downward-draining cylindrical capacitor according to claim 1, characterized in that: The adapter plate (42), the upper cover plate (41), and the negative electrode post (43) are sequentially fitted onto the connecting post (44). The upper cover plate (41) is welded and fixed onto the shell (1). The adapter plate (42) is welded to the negative electrode current collector (3).

6. The single-cell, downward-draining cylindrical capacitor according to claim 5, characterized in that: The negative electrode terminal (43) is made of aluminum, and the connecting post (44) is made of copper.

7. The single-cell, downward-draining cylindrical capacitor according to claim 1, characterized in that: The negative electrode cover plate assembly (4) is fixedly connected to the top of the housing (1), and the positive electrode cover plate (6) is fixedly connected to the bottom of the housing (1).

Images