Blade battery cell and battery pack
By adopting the design of split assembly and split pole columns in the power battery cell, the problem of space occupation and assembly interference between the pole columns and the pole group is solved, and more efficient space utilization and production efficiency are achieved.
Patent Information
- Application Number
- CN202422140348.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-30
- Publication Date
- 2025-06-20
- Estimated Expiration
- 2034-08-30
AI Technical Summary
When the existing power battery cells are connected to the pole column and the pole group, they occupy a lot of internal space in the case, and various parts of the structures are easily interfered during the assembly process, affecting production efficiency.
The blade battery cell design is adopted, and the shell and cover plate are assembled in a split type, and the pole column is divided at both ends of the shell, and the through grooves and step grooves are opened to facilitate the welding operation of the pole ears and the connecting piece, and the shell space is closed through the sealing plate to reduce structural interference.
It improves the space utilization rate in the shell, reduces assembly difficulty and production costs, and improves battery performance and production efficiency.
Smart Images
Figure CN223006877U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of power batteries, in particular to a blade battery cell and a battery pack. Background Art
[0002] Power batteries are the main power source of new energy vehicles, responsible for providing continuous and stable electrical energy for the vehicles. A power battery is composed of multiple cells connected in series. Each cell includes a housing and an internal electrode group. Positive and negative electrode tabs are provided on the electrode group for leading out the current of the electrode group. A terminal post is provided on the housing, and the terminal post is connected to the corresponding electrode tab through a connecting piece, thereby connecting the cell to the circuit. After the assembly of the power battery cell is completed, it is necessary to evacuate the inside of the cell from the liquid injection hole of the cell, and then inject liquid electrolyte into the cell to improve the performance and service life of the battery.
[0003] In the related art, in order to facilitate the connection of the cell to the power supply circuit, the terminal posts and the liquid injection holes of some cells are both provided at the top of the housing. The electrode tabs led out from the electrode group are provided on the lower side of the terminal post, and a connecting piece is provided on the lower side of the terminal post. Since the electrode tab needs to be directly or indirectly connected to the terminal post, the electrode tab needs to be provided near the terminal post. The electrode tab led out from the electrode group is provided on the lower side of the terminal post, and a connecting piece is provided on the lower side of the terminal post. The connecting piece is set as a U-shaped with two parallel connecting parts. The two connecting parts of the connecting piece are arranged up and down relatively. One connecting part is connected to the bottom end of the terminal post, and the other is connected to the electrode tab, thereby realizing the connection between the terminal post and the electrode group.
[0004] However, in the above-mentioned related art, the longitudinal arrangement of the electrode tab, the connecting piece and the terminal post will occupy more internal space of the housing. At the same time, the structures of each part interfere with each other, which causes certain obstacles to the bending of the electrode tab and the welding between the electrode tab and the connecting piece, affecting the production efficiency. Summary of the Utility Model
[0005] In view of this, the utility model provides a blade battery cell and a battery pack to solve the problem that the structure realizing the conduction between the terminal post and the electrode group occupies more internal space of the housing, and the structures of each part are prone to interference during the assembly process of the cell, affecting the production efficiency.
[0006] In a first aspect, the present utility model provides a blade battery cell, comprising: a housing having openings at opposite ends; a first cover plate and a second cover plate, the peripheral contours of the first cover plate and the second cover plate respectively matching the shapes of the openings at opposite ends of the housing, a first pole column being provided on the first cover plate, a second pole column being provided on the second cover plate, a through groove being formed in the first cover plate, and a stepped groove being provided at the notch of the through groove on the side away from the housing; a connecting piece disposed on the side of the first cover plate facing the inside of the housing, one end of the connecting piece being connected to the first pole column and the other end extending to the position of the through groove; a pole group disposed in the housing and connected to the second cover plate, a first pole tab being provided at one end of the pole group facing the first cover plate, the first pole tab being connected to the connecting piece, a second pole tab being provided at one end of the pole group facing the second cover plate, the second pole tab being connected to the second pole column; and a sealing plate, the peripheral contour of the sealing plate matching the contour of the stepped groove and sealing the through groove.
[0007] Beneficial effects: The housing is designed with a split assembly with the first cover plate and the second cover plate, which facilitates the insertion of the electrode group into the housing. The first cover plate and the second cover plate are used to close the openings at both ends of the housing, achieving the limitation and protection of the electrode group. At the same time, the first pole and the second pole are respectively arranged at opposite ends of the housing, so that the internal structure is dispersed at both ends of the housing, avoiding the interference during the assembly process caused by crowded structures. A through groove is opened on the first cover plate, and the first tab of the electrode group is led out from the position of the through groove. After the battery is assembled, it is convenient for the staff to operate the tab. A connecting piece is arranged below the first one. One end of the connecting piece is located at the lower end of the first pole and is connected to the first pole, while the other end extends laterally to a position opposite to the through groove, facilitating connection with the first tab, enabling the staff to conveniently weld the first tab and the connecting piece through the through groove position. Finally, by installing a sealing plate at the through groove, the space on the side of the housing facing the first cover plate is closed to protect structures such as the connecting piece and the first tab. Since the tab led out from the electrode group is arranged opposite to the corresponding through groove and is located laterally to the first pole, when electrically connecting the first tab and the first pole, the connecting piece can be set into a structure similar to a rectangular plate, thus saving the longitudinal space inside the housing. In addition, due to the connecting piece being set into a structure similar to a rectangular plate, when the first tab is connected to the connecting piece, the first tab has more sufficient bending space, facilitating the control of the bending angle of the first tab to improve the connection stability between the first tab and the connecting piece, and also being able to further reduce the occupation of the longitudinal space inside the housing. The entire battery cell structure greatly improves the space utilization rate inside the housing, which is equivalent to increasing the volume of the electrode group that can be arranged inside the housing of the same volume, and can effectively improve the battery performance. At the same time, due to the staggered arrangement of the first tab, the connecting piece and the first pole in the horizontal direction, the components at one end of the battery cell located on the first cover plate are not prone to interference, reducing the difficulty of assembling and welding of each component and improving the production efficiency. In addition, during the actual installation process, the electrode group is first connected to the second cover plate. After the second pole on the second cover plate is connected to the second tab, the second cover plate is fixed to the electrode group, and then they are jointly installed into the housing. Subsequently, structures such as the first tab, the connecting piece, the first cover plate, and the sealing plate are installed in sequence to complete the assembly of the blade battery cell. The operation is simple, and each component is not prone to interference, improving the assembly efficiency.
[0008] In an alternative embodiment, the depth of the step groove is d, the thickness of the first cover plate is T, and the depth d of the step groove and the thickness of the first cover plate satisfy 0.25T ≤ d ≤ 0.8T.
[0009] Beneficial effects: By controlling the ratio between the depth of the stepped groove and the thickness of the first cover plate, it is prevented that when the ratio is too small, the sealing plate cannot be completely pressed into the stepped groove, resulting in protrusions on the first cover plate, which affects the subsequent assembly of the patch on the top of the blade battery cell. At the same time, it is also prevented that when the ratio is too large, after the sealing plate is pressed into the stepped groove, the bonding strength at the stepped groove is weak, and the stepped groove is prone to depression, resulting in the failure of the sealing plate installation structure, or affecting the welding of the sealing plate and the first cover plate.
[0010] In an alternative embodiment, the thickness of the sealing plate is less than the depth of the stepped groove, and the difference between the thickness of the sealing plate and the depth of the stepped groove is a, and 0.2 mm ≤ a ≤ 0.5 mm.
[0011] Beneficial effects: By controlling the difference between the thickness of the sealing plate and the depth of the stepped groove, when the sealing plate is pressed into the stepped groove and the sealing plate is welded to the first cover plate, it is prevented that the protrusions generated at the welded part are higher than the surface of the first cover plate, thereby avoiding the situation that affects the assembly of the patch on the top of the blade battery cell and ensuring the assembly efficiency.
[0012] In an alternative embodiment, the first cover plate is provided with a connection hole, the first pole passes through the connection hole and extends out of the first cover plate, the first cover plate is further provided with a riveting block, the riveting block is provided with a clamping hole, and the first pole passes through the clamping hole and is clamped with the riveting block.
[0013] Beneficial effects: By providing a riveting block, the riveting block is located on the side of the first cover plate away from the housing. Since the riveting block cannot pass through the connection hole and the riveting block is clamped with the first pole, the first cover plate and the first pole can be relatively positioned. In addition, the riveting block increases the contact area between the first pole and the power connection structure, avoiding the situation of poor contact during the power connection process of the blade battery cell.
[0014] In an alternative embodiment, an insulating pad is fixedly provided on the lower surface of the sealing plate.
[0015] Beneficial effects: By providing an insulating pad on the lower surface of the sealing plate, the sealing plate is separated from the first pole ear and the connecting piece, avoiding the short circuit between the pole ear or the sealing plate and the sealing plate, resulting in the leakage of the housing.
[0016] In an alternative embodiment, a first insulating member is provided on the side of the riveting block facing the first cover plate, and the edge of the first insulating member is bent towards the riveting block and wraps around the periphery of the riveting block to separate the riveting block from the first cover plate.
[0017] Beneficial effects: By providing the first insulating member, the riveting block in direct contact with the first pole is separated from the housing, preventing short-circuiting between the first pole and the housing. At the same time, the first insulating member is elastic and can squeeze the riveting block and the first cover plate when the first pole and the riveting block are clamped, thus avoiding jitter caused by gaps in the clamping connection between the riveting block and the first pole, and further avoiding loosening of the connection structure between the riveting block and the first pole. In addition, the first insulating member is arranged around the connection hole, and at the same time functions to enhance the sealing performance at the connection hole.
[0018] In an alternative embodiment, a sealing ring is provided in the connection hole. The sealing ring surrounds the circumference of the first pole, separating the first pole from the first cover plate and sealing the connection hole.
[0019] Beneficial effects: By providing the sealing ring to surround the first pole, the sealing performance at the connection hole is improved, preventing leakage of the battery core liquid and entry of external liquid into the battery core. At the same time, the first pole is also separated from the first cover plate to avoid short-circuiting, improving the reliability of the battery core.
[0020] In an alternative embodiment, a second insulating member is provided on the side of the first cover plate facing the inside of the housing. The second insulating member is located between the first cover plate and the connecting piece. The second insulating member is provided with a relief groove, and the size of the relief groove is slightly smaller than that of the through groove and is arranged opposite to the through groove.
[0021] Beneficial effects: By providing the second insulating member on the side of the first cover plate facing the housing, the first cover plate is separated from the connecting piece, enabling the connecting piece to extend to the side of the through groove close to the middle of the cover plate, so that it has sufficient length and will not be short-circuited with the cover plate, effectively preventing the housing from leaking electricity. In addition, since the connecting piece has sufficient length, it also provides sufficient space for the connection between the connecting piece and the first tab, reducing the situation that the poor contact between the first tab and the connecting piece affects the performance of the battery core.
[0022] In an alternative embodiment, an explosion-proof valve and a liquid injection hole are provided on the second cover plate. The explosion-proof valve is located on the circumference of the second pole, and the liquid injection hole is located on the circumference of the explosion-proof valve.
[0023] Beneficial effects: The setting of the explosion-proof valve improves the safety factor of the battery core. The setting of the liquid injection hole facilitates injecting liquid electrolyte into the battery during the processing to infiltrate the electrode group and improve the performance of the battery core. Since both the liquid injection hole and the explosion-proof valve are provided on the second cover plate without the through groove, the disturbance to the welding joint between the first tab and the connecting piece during the injection of liquid electrolyte is reduced, thereby reducing the situation that the liquid injection hole is blocked. At the same time, the structural layout of the blade battery core is made more reasonable, avoiding the interference of structures such as the liquid injection hole and the explosion-proof valve with the welding operation of the first tab and the connecting piece at the through groove during the assembly process.
[0024] In a second aspect, the present utility model further provides a battery pack, comprising: a plurality of the above-mentioned blade battery cells.
[0025] Beneficial effects: The battery cell group in the battery pack is composed of the above-mentioned blade battery cells, thereby improving the reliability of the battery pack and the production efficiency of the battery pack. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.
[0027] Figure 1 Schematic diagram of a blade battery cell according to an embodiment of the present utility model for showing the structure of the cell at the end where the first cover plate is located;
[0028] Figure 2 Schematic diagram of a blade battery cell according to an embodiment of the present utility model for showing the structure of the cell at the end where the second cover plate is located;
[0029] Figure 3 Schematic diagram of a blade battery cell according to an embodiment of the present utility model for showing the structure of the outer plate surface of the first cover plate facing the cell;
[0030] Figure 4 Schematic diagram of a blade battery cell according to an embodiment of the present utility model for showing the structure of the inner plate surface of the first cover plate facing the cell;
[0031] Figure 5 Schematic diagram of a blade battery cell according to an embodiment of the present utility model for showing the structure at the second cover plate;
[0032] Figure 6 Schematic cross-sectional view of a blade battery cell according to an embodiment of the present utility model for showing the internal structure of the cell
[0033] Figure 7 For Figure 6 partial enlargement of A in
[0034] Figure 8 For Figure 6 partial enlargement of B in
[0035] Figure 9 Schematic diagram of a blade battery cell according to an embodiment of the present utility model for showing the state before welding of the first tab and the connecting piece at the first cover plate.
[0036] Description of the reference numerals:
[0037] 100, housing; 101, opening; 201, first cover plate; 2011, first pole; 2012, through groove; 2013, stepped groove; 2014, connection hole; 202, second cover plate; 2021, second pole; 300, connecting piece; 400, pole group; 401, first pole tab; 500, sealing plate; 600, riveting block; 601, clamping hole; 701, insulating pad; 702, first insulating member; 703, sealing ring; 704, second insulating member; 800, explosion-proof valve; 900, liquid injection hole. Detailed implementation manners
[0038] To make the objectives, technical solutions and advantages of the embodiments of the present utility model clearer, the technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.
[0039] The following will be combined with Figures 1 to 9 , to describe the embodiments of the present utility model.
[0040] According to an embodiment of the present utility model, on the one hand, a blade battery cell is provided, including: a housing 100 with openings 101 provided at opposite ends; a first cover plate 201 and a second cover plate 202, the peripheral contours of the first cover plate 201 and the second cover plate 202 respectively match the shapes of the openings 101 at opposite ends of the housing 100, a first pole 2011 is provided on the first cover plate 201, a second pole 2021 is provided on the second cover plate 202, a through groove 2012 is formed on the first cover plate 201, and a stepped groove 2013 is provided at the notch of the through groove 2012 on the side away from the housing 100; a connecting piece 300, disposed on the side of the first cover plate 201 facing the inside of the housing 100, one end of the connecting piece 300 is connected to the first pole 2011, and the other end extends to the position of the through groove 2012; a pole group 400, disposed inside the housing 100 and connected to the second cover plate 202, a first pole tab 401 is provided at the end of the pole group 400 facing the first cover plate 201, the first pole tab 401 is connected to the connecting piece 300, a second pole tab is provided at the end of the pole group 400 facing the second cover plate 202, and the second pole tab is connected to the second pole 2021; a sealing plate 500, the peripheral contour of the sealing plate 500 matches the contour of the stepped groove 2013 and seals the through groove 2012.
[0041] In this embodiment, the housing 100 is designed with a split assembly with the first cover plate 201 and the second cover plate 202, which facilitates the installation of the electrode group 400 into the housing 100. The first cover plate 201 and the second cover plate 202 are used to close the two ends of the housing 100, thereby realizing the limiting and protection of the electrode group 400. At the same time, the first terminal 2011 and the second terminal 2021 are respectively arranged at opposite ends of the housing 100, so that the internal structure is dispersed on both sides of the housing 100, avoiding interference during the assembly process caused by structural congestion. A through groove 2012 is formed on the first cover plate 201, and the first tab 401 of the electrode group 400 is led out from the position of the through groove 2012. After the battery is assembled, it is convenient for the staff to operate on the tab. A connecting piece 300 is arranged below the first one. One end of the connecting piece 300 is located at the lower end of the first terminal 2011 and is connected to the first terminal 2011, while the other end extends laterally to a position opposite to the through groove 2012, facilitating connection with the first tab 401, enabling the staff to conveniently perform welding operations on the first tab 401 and the connecting piece 300 through the position of the through groove 2012. Finally, by installing a sealing plate 500 at the through groove 2012, the space on the side of the housing 100 facing the first cover plate 201 is closed, protecting structures such as the connecting piece 300 and the first tab 401. Since the tab led out from the electrode group 400 is disposed opposite to the corresponding through groove 2012 and is located laterally of the corresponding terminal, when electrically connecting the first tab 401 to the first terminal 2011, the connecting piece 300 can be set to an approximately rectangular plate-like structure, thereby saving the longitudinal space inside the housing 100. In addition, since the connecting piece 300 is set to an approximately rectangular plate-like structure, when the first tab 401 is connected to the connecting piece 300, the first tab 401 has more sufficient bending space, facilitating the control of the bending angle of the first tab 401 to improve the connection stability between the first tab 401 and the connecting piece 300, and also being able to further reduce the occupation of the longitudinal space inside the housing 100. The entire battery cell structure greatly improves the space utilization rate inside the housing 100, which is equivalent to increasing the volume of the electrode group 400 that can be arranged inside the housing 100 of the same volume, effectively improving the battery performance. At the same time, since the first tab 401, the connecting piece 300, and the first terminal 2011 are arranged with a horizontal offset, the components at one end of the first cover plate 201 of the battery cell are not prone to interference, reducing the difficulty of assembly and welding of each component and improving the production efficiency. In addition, during the actual installation process, the electrode group 400 is first connected to the second cover plate 202. After the second terminal 2021 on the second cover plate 202 is connected to the second tab, the second cover plate 202 and the electrode group 400 are fixed, and then they are jointly installed into the housing 100. Subsequently, structures such as the first tab 401, the connecting piece 300, the first cover plate 201, and the sealing plate 500 are installed in sequence to complete the assembly of the blade battery cell. The operation is simple, and each component is not prone to interference, improving the assembly efficiency.
[0042] Specifically, in the above embodiment, the electrode group 400 includes at least one electrode core. The positive electrode tab and the negative electrode tab of the electrode core are the first tab 401 and the second tab respectively. The electrode group 400 is first connected to the second cover plate 202. It should be noted that this embodiment does not limit the specific connection form between the second tab and the second terminal 2021. The second tab can be directly welded to the second terminal 2021, or indirectly connected to the second tab through a connection structure. After the second cover plate 202 and the electrode group 400 are spliced into an integral structure, the electrode group 400 and the second cover plate 202 are inserted into the housing 100 from the opening 101 at one end of the housing 100, and the second cover plate 202 is welded and fixed to the housing 100. At this time, the first tab 401 is opposite to the position of the through groove 2012. A connecting piece 300 is provided on the side of the first cover plate 201 facing the housing 100. The connecting piece 300 is connected to the end of the first terminal 2011 and extends along the length direction of the cover plate to be opposite to the through groove 2012. At this time, the first tab 401 extends out of the through groove 2012 from one side of the connecting piece 300. The operator bends the first tab 401 so that the first tab 401 adheres to the surface of the connecting piece 300 facing the through groove 2012, which is convenient for welding operation. After the first tab 401 is welded to the connecting piece 300, the first tab 401 and the first terminal 2011 are in a conductive state, forming the positive electrode structure of the blade battery. Subsequently, the operator presses the sealing plate 500 into the step groove 2013 and welds the sealing plate 500 to the first cover plate 201 to complete the assembly of a single blade battery cell.
[0043] In one embodiment, the depth of the step groove 2013 is d, and the thickness of the first cover plate 201 is T. The depth d of the step groove 2013 and the thickness of the first cover plate 201 satisfy 0.25T ≤ d ≤ 0.8T.
[0044] Specifically, the depth d of the step groove 2013 is the distance between the plate surface of the first cover plate 201 away from the housing 100 and the step surface of the step groove 2013.
[0045] In this embodiment, by controlling the ratio between the depth of the step groove 2013 and the thickness of the cover plate, it is prevented that if the ratio is too small, the sealing plate 500 cannot be completely pressed into the step groove 2013, resulting in protrusions on the first cover plate 201, affecting the assembly of the subsequent patch on the top of the blade battery cell. At the same time, it is also prevented that if the ratio is too large, after the sealing plate 500 is pressed into the step groove 2013, the bonding strength at the step groove 2013 is weak, and the step groove 2013 is prone to depression, resulting in the failure of the installation structure of the sealing plate 500, or affecting the welding of the sealing plate 500 to the first cover plate 201.
[0046] In one embodiment, the thickness of the sealing plate 500 is less than the depth of the step groove 2013, and the difference between the thickness of the sealing plate 500 and the depth of the step groove 2013 is a, and 0.2 mm ≤ a ≤ 0.5 mm.
[0047] In this embodiment, by controlling the difference between the thickness of the sealing plate 500 and the depth of the step groove 2013, when the sealing plate 500 is pressed into the step groove 2013 and the sealing plate 500 is welded to the first cover plate 201, the protrusion generated at the welded part does not protrude above the surface of the first cover plate 201, thereby avoiding the situation that affects the assembly of the patch on the top of the blade battery cell and ensuring the assembly efficiency.
[0048] In one embodiment, a connection hole 2014 is provided on the first cover plate 201. The first pole column 2011 passes through the connection hole 2014 and extends out of the first cover plate 201. A riveting block 600 is further provided on the first cover plate 201. A clamping hole 601 is provided on the riveting block 600. The first pole column 2011 passes through the clamping hole 601 and is clamped with the riveting block 600.
[0049] It should be noted that the second cover plate 202 may also be provided with a riveting block 600, and the second pole column 2021 is positioned with the second cover plate 202 through the riveting block 600. In some embodiments not shown, the second cover plate 202 is not provided with a riveting block 600, and the second pole column 2021 is exposed outside the second cover plate 202 after passing through the second cover plate 202.
[0050] In this embodiment, by providing the riveting block 600, the riveting block 600 is located on the side of the first cover plate 201 away from the housing 100. Since the riveting block 600 cannot pass through the connection hole 2014 and the riveting block 600 is clamped with the first pole column 2011, the first cover plate 201 and the first pole column 2011 can be relatively positioned. In addition, the riveting block 600 increases the contact area between the first pole column 2011 and the power connection structure, avoiding the situation of poor contact during the power connection process of the blade battery cell.
[0051] In one embodiment, an insulating pad 701 is fixedly provided on the lower surface of the sealing plate 500.
[0052] In this embodiment, by providing the insulating pad 701 on the lower surface of the sealing plate 500, the sealing plate 500 is separated from the first pole ear 401 and the connecting piece 300, avoiding the short circuit between the pole ear or the sealing plate 500 and the sealing plate 500, resulting in the leakage of the housing 100.
[0053] In one embodiment, a first insulating member 702 is provided on the side of the riveting block 600 facing the first cover plate 201. The edge position of the first insulating member 702 is bent towards the riveting block 600 and wraps around the periphery of the riveting block 600, separating the riveting block 600 from the first cover plate 201.
[0054] In this embodiment, by providing the first insulating member 702, the riveting block 600 in direct contact with the first pole 2011 is separated from the housing 100, preventing the short circuit between the first pole 2011 and the housing 100. Meanwhile, the first insulating member 702 is elastic and can squeeze the riveting block 600 and the first cover plate 201 when the first pole 2011 and the riveting block 600 are clamped tightly, thereby avoiding the jitter caused by the gap between the riveting block 600 and the first pole 2011, and further avoiding the loosening of the connection structure between the riveting block 600 and the first pole 2011. In addition, the first insulating member 702 is arranged around the connection hole 2014, and also functions to enhance the sealing performance at the connection hole 2014.
[0055] In one embodiment, a sealing ring 703 is provided in the connection hole 2014. The sealing ring 703 is disposed around the circumference of the first pole 2011, separating the first pole 2011 from the first cover plate 201 and sealing the connection hole 2014.
[0056] In this embodiment, by providing the sealing ring 703, the sealing ring 703 is arranged around the first pole 2011, improving the sealing performance at the connection hole 2014, preventing the leakage of the battery core liquid and the entry of external liquid into the battery core, and at the same time separating the first pole 2011 from the first cover plate 201 to avoid short circuit, enhancing the reliability of the battery core.
[0057] In one embodiment, a second insulating member 704 is provided on the side of the first cover plate 201 facing the inside of the housing 100. The second insulating member 704 is located between the first cover plate 201 and the connecting piece 300. The second insulating member 704 is provided with a relief groove, and the size of the relief groove is slightly smaller than the through groove 2012 and is arranged opposite to the through groove 2012.
[0058] In this embodiment, by providing the second insulating member 704 on the side of the first cover plate 201 facing the housing 100, the first cover plate 201 is separated from the connecting piece 300, enabling the connecting piece 300 to extend to the side of the through groove 2012 close to the middle of the cover plate, so that it has sufficient length and will not be short-circuited with the cover plate, effectively preventing the leakage of the housing 100. In addition, since the connecting piece 300 has sufficient length, it also provides sufficient space for the connection between the connecting piece 300 and the first tab 401, reducing the situation that the poor contact between the first tab 401 and the connecting piece 300 affects the performance of the battery core.
[0059] In one embodiment, an explosion-proof valve 800 and a liquid injection hole 900 are provided on the second cover plate 202. The explosion-proof valve 800 is located on the circumference of the second pole 2021, and the liquid injection hole 900 is located on the circumference of the explosion-proof valve 800.
[0060] In this embodiment, the provision of the explosion-proof valve 800 improves the safety factor of the battery cell, and the provision of the liquid injection hole 900 facilitates the injection of liquid electrolyte into the battery during the manufacturing process to soak the electrode assembly 400, thereby improving the performance of the battery cell. Since both the liquid injection hole 900 and the explosion-proof valve 800 are provided on the second cover plate 202 without the through groove 2012, the disturbance to the welding joint between the first tab 401 and the connecting piece 300 during the injection of liquid electrolyte is reduced, thereby reducing the situation where the liquid injection hole 900 is blocked. At the same time, the structural layout of the blade battery cell is made more reasonable, avoiding the interference of structures such as the liquid injection hole 900 and the explosion-proof valve 800 with the welding operation of the first tab 401 and the connecting piece 300 at the through groove 2012 during the assembly process.
[0061] According to an embodiment of the present invention, on the other hand, a battery pack is further provided, including: a plurality of the above-mentioned blade battery cells.
[0062] In this embodiment, the battery cell group in the battery pack is composed of the battery cells of the above-mentioned blade battery, thereby improving the reliability of the battery pack and the production efficiency of the battery pack.
[0063] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations fall within the scope defined by the appended claims.
Claims
1. A blade battery cell, characterized in that: include: A shell having openings at opposite ends; A first cover plate and a second cover plate, wherein the peripheral profiles of the first cover plate and the second cover plate are respectively adapted to the opening shapes of opposite ends of the shell, a first pole is provided on the first cover plate, a second pole is provided on the second cover plate, a through groove is provided on the first cover plate, and a step groove is provided at the notch of the through groove away from the shell; A connecting piece, arranged on a side of the first cover plate facing the inside of the housing, one end of the connecting piece is connected to the first pole, and the other end of the connecting piece extends to the position of the through slot; A pole group, arranged in the housing and connected to the second cover plate, a first pole lug is arranged at one end of the pole group facing the first cover plate, the first pole lug is connected to the connecting sheet, a second pole lug is arranged at one end of the pole group facing the second cover plate, the second pole lug is connected to the second pole column; A sealing plate, the peripheral side profile of the sealing plate is adapted to the profile of the step groove and seals the through groove.
2. The blade battery cell according to claim 1, characterized in that: The depth of the step groove is d, the thickness of the first cover plate is T, and the depth d of the step groove and the thickness of the first cover plate satisfy 0.25T≤d≤0.8T.
3. The blade battery cell according to claim 2, characterized in that: The thickness of the sealing plate is smaller than the depth of the step groove, and the difference between the thickness of the sealing plate and the depth of the step groove is a, and 0.2 mm≤a≤0.5 mm.
4. The blade battery cell according to any one of claims 1 to 3, characterized in that: The first cover plate is provided with a connecting hole, the first pole passes through the connecting hole and extends out of the first cover plate, the first cover plate is also provided with a rivet block, the rivet block is provided with a clamping hole, the first pole passes through the clamping hole and is clamped with the rivet block.
5. The blade battery cell according to claim 4, characterized in that: An insulating pad is fixedly arranged on the lower surface of the sealing plate.
6. The blade battery cell according to claim 5, characterized in that: A first insulating member is provided on one side of the riveting block facing the first cover plate, and an edge of the first insulating member is bent toward the riveting block and covers the periphery of the riveting block to separate the riveting block from the first cover plate.
7. The blade battery cell according to claim 6, characterized in that: A sealing ring is provided in the connection hole, and the sealing ring is arranged around the circumference of the first pole to separate the first pole from the first cover plate and seal the connection hole.
8. The blade battery cell according to claim 7, characterized in that: A second insulating member is provided on one side of the first cover plate facing the inside of the shell, the second insulating member is located between the first cover plate and the connecting sheet, and the second insulating member is provided with a clearance groove, the size of the clearance groove is slightly smaller than the through groove and is arranged opposite to the through groove.
9. The blade battery cell according to claim 8, characterized in that: The second cover plate is provided with an explosion-proof valve and a liquid injection hole. The explosion-proof valve is located on the peripheral side of the second pole, and the liquid injection hole is located on the peripheral side of the explosion-proof valve.
10. A battery pack, characterized in that: include: A plurality of blade battery cells according to any one of claims 1 to 9.