Battery

Abstract

The utility model provides a battery which comprises a shell and a battery cell, the battery cell comprises a first pole piece, a second pole piece and a diaphragm, a first pole lug is arranged on the first pole piece, and a second pole lug is arranged on the second pole piece; the shell is provided with a top sealing edge and two side sealing edges, and the two side sealing edges are arranged on the two opposite sides of the shell in the first direction respectively. The shell is provided with two notches, the two notches are located in the edge of one side, in the second direction, of the shell, the notches correspond to the side sealing edges in a one-to-one mode, and the notches are located in the intersecting positions of the side sealing edges and the top sealing edge. A groove is formed in the edge of one side, in the second direction, of the battery cell, the groove comprises a first groove area and a second groove area, the first tab is partially located in the first groove area, and the second tab is partially located in the second groove area; therefore, the situation that the top of the side sealing edge interferes with other parts at the top of the battery or collides with a battery bin and the like is avoided, and meanwhile, the energy density of the unit volume of the battery cell is effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, specifically to a battery. Background Technology

[0002] Currently, lithium-ion batteries are widely used not only in portable electronic devices such as mobile phones and laptops, but also in electric vehicles, electric bicycles and other electric equipment.

[0003] Lithium-ion batteries consist of a casing and a cell. The casing covers the outside of the cell and has a top seal and side seals. In related technologies, the top of the side seal can easily interfere with other components on the top of the battery, affecting the normal assembly of the battery. Furthermore, when the battery is impacted, the side seal poses a risk of impacting the battery compartment of the equipment. Utility Model Content

[0004] In view of this, the present invention aims to provide a battery that can, to a certain extent, avoid interference between the side seal and other components on the top of the battery, and avoid the risk of the side seal impacting the battery compartment.

[0005] This utility model provides a battery, including a casing and a battery cell, wherein the casing covers the outside of the battery cell;

[0006] The battery cell includes a first electrode, a second electrode, and a separator disposed between the first electrode and the second electrode; the first electrode and the second electrode have opposite polarities, and the first electrode, the separator, and the second electrode are stacked in sequence.

[0007] The first electrode plate is provided with a first electrode tab, and the second electrode plate is provided with a second electrode tab;

[0008] The housing has a top sealing edge and two side sealing edges, the two side sealing edges being respectively disposed on opposite sides of the housing along a first direction; the first electrode lug and the second electrode lug extend from the top sealing edge;

[0009] The housing has two notches, which are located on one side edge of the housing along the second direction. The notches correspond one-to-one with the side sealing edge, and the notches are located at the intersection of the side sealing edge and the top sealing edge.

[0010] The battery cell has a groove on one side edge along the second direction. The groove includes a first groove area and a second groove area, and the first groove area and the second groove area are arranged at intervals along the first direction.

[0011] The first electrode tab is located within the first groove area, and the second electrode tab is located within the second groove area.

[0012] Optionally, along the first direction, the width W1 of the notch satisfies: 0.3mm≤W1≤3mm;

[0013] And / or, along the first direction, the ratio of the width W1 of the notch to the width W2 of the housing satisfies: 0.07 ≤ W1 / W2 ≤ 0.12;

[0014] And / or, along the second direction, the height L1 of the notch satisfies: 0.3mm≤L1≤3mm;

[0015] And / or, along the second direction, the ratio of the height L1 of the notch to the height L2 of the housing satisfies: 0.05≤L1 / L2≤0.1.

[0016] Optionally, the notch is an arc-shaped notch recessed toward the inner cavity of the housing;

[0017] Alternatively, the width of the notch in the first direction gradually decreases linearly in the direction toward the side seal edge;

[0018] Alternatively, along the second direction, the width of the notch is equal at different locations in the first direction.

[0019] Optionally, the shell includes a shell body, a top sealing area, a side sealing area, and a notch sealing area;

[0020] The casing body covers the outside of the battery cell, the top sealing area is located on one side of the casing body along the second direction, and the first tab and the second tab extend from the top sealing area;

[0021] There are two side sealing areas, and the two side sealing areas are located on opposite sides of the shell body along the first direction;

[0022] There are two notch sealing areas, each corresponding to a side sealing area, and located between the top sealing area and the corresponding side sealing area.

[0023] The top sealing area and part of the notch sealing area are bent toward the shell body to form the top sealing edge; the side sealing area and part of the notch sealing area are bent toward the shell body at least once to form the side sealing edge.

[0024] Optionally, along the first direction, the ratio of the width W3 of the top sealing area to the width W2 of the shell satisfies: 0.88≤W3 / W2≤0.93;

[0025] And / or, along the second direction, the height L3 of the top sealing area satisfies: 1mm≤L3≤5mm;

[0026] And / or, along the second direction, the ratio of the height L3 of the top sealing area to the height L2 of the shell satisfies: 0.1≤L3 / L2≤0.2.

[0027] Optionally, along the first direction, the width W4 of the side sealing area satisfies: 1mm≤W4≤5mm;

[0028] And / or, along a third direction, the ratio of the thickness H2 of the side seal to the thickness H1 of the shell body satisfies: 0.8mm≤H2 / H1≤0.98mm;

[0029] And / or, the side of the side seal facing the shell body is connected to the shell body by an adhesive.

[0030] Optionally, along the fifth direction, the height L5 of the notch sealing area satisfies: 1mm≤L5≤5mm;

[0031] And / or, the ratio of the height L5 of the notch sealing area along the fifth direction to the height L2 of the shell along the second direction satisfies: 0.1≤L5 / L2≤0.2.

[0032] Optionally, along the first direction, the distance d1 between the battery cell and the inner wall of the housing satisfies: 0.2mm≤d1≤1mm;

[0033] And / or, along the second direction, the distance d2 between the cell and the inner wall of the housing satisfies: 0.2mm≤d2≤1mm.

[0034] Optionally, a first notch is provided at the position corresponding to the notch on the first electrode;

[0035] The second electrode has a second notch at the position corresponding to the notch;

[0036] The diaphragm has a diaphragm notch at the position corresponding to the notch.

[0037] Optionally, the projection edge of the second electrode on the first electrode is located within the area enclosed by the first electrode;

[0038] The distance s1 between one edge of the projection of the second electrode onto the first electrode in the first direction and one edge of the first electrode along the first direction satisfies: 0.3mm < s1 < 1mm;

[0039] And / or, the distance s2 between one edge of the projection of the second electrode onto the first electrode in the second direction and one edge of the first electrode along the second direction satisfies: 0.3mm < s2 < 1mm.

[0040] Optionally, the first electrode tab includes a first main electrode tab and a first electrode tab foil extending from one side of the first electrode sheet along the second direction, all of the first electrode tab foils being connected to the first main electrode tab;

[0041] The second electrode tab includes a second main electrode tab and a second electrode tab foil extending from one side of the second electrode plate along the second direction, all of the second electrode tab foils being connected to the second main electrode tab;

[0042] At least a portion of the first electrode foil is located within the first groove region, and at least a portion of the second electrode foil is located within the second groove region; the first main electrode and the second main electrode extend from the top sealing edge, respectively.

[0043] Optionally, at least a portion of the connection area between all the first electrode foils and the first main electrode is located within the first groove area;

[0044] At least a portion of the connection area between all the second electrode foils and the second main electrode is located within the second groove area.

[0045] Optionally, along the first direction, the width W8 of each of the connecting areas satisfies: 4mm≤W8≤12mm;

[0046] And / or, along the second direction, the height L8 of each of the connecting areas satisfies: 0.3mm≤L8≤5mm;

[0047] And / or, along the first direction, the distance D1 between each of the connecting areas and the groove wall of the groove area satisfies: 0.5mm≤D1≤3mm;

[0048] And / or, along the second direction, the distance D2 between each of the connecting areas and the bottom of the groove area satisfies: 0.5mm≤D2≤2mm.

[0049] Optionally, the first electrode sheet has two first grooves on one side along the second direction, and the first electrode tab foil is located in one of the first grooves;

[0050] The diaphragm is provided with a diaphragm groove at a position corresponding to the first groove.

[0051] The second electrode has two second grooves on one side along the second direction. The second grooves correspond one-to-one with the first grooves, and one of the second grooves corresponds to the first electrode foil. The second electrode foil is located in the other second groove.

[0052] Along a third direction, a first groove region is defined by a corresponding group of the first groove portion, the second groove portion, and the diaphragm groove portion, and a second groove region is defined by a corresponding other group of the first groove portion, the second groove portion, and the diaphragm groove portion.

[0053] Optionally, along the first direction, the groove width W9 of the first groove portion satisfies: 5mm≤W9≤15mm;

[0054] And / or, along the second direction, the groove depth L9 of the first groove portion satisfies: 2mm≤L9≤6mm;

[0055] And / or, along the first direction, the ratio of the width W10 of the first tab foil to the groove width W9 of the first groove portion satisfies: 0.8≤W10 / W9≤0.95;

[0056] And / or, along the second direction, the ratio between the groove depth L9 of the first groove portion and the height L2 of the housing satisfies: 0.1≤L9 / L2≤0.25.

[0057] Optionally, the projection edge of the second electrode on the first electrode is located within the area enclosed by the first electrode;

[0058] Along the first direction, the relationship between the groove width W11 of the second groove and the groove width W9 of the first groove satisfies: 0.3mm < W11 - W9 < 1mm;

[0059] And / or, along the second direction, the relationship between the groove depth L11 of the second groove and the groove depth L9 of the first groove satisfies: 0.3mm < L9 - L11 < 1mm.

[0060] Optionally, the battery further includes a protection board located on the side of the top seal opposite to the battery cell, and the first tab and the second tab are respectively connected to the protection board;

[0061] The projection of the protective plate in the first direction overlaps with the projection of the notch in the first direction.

[0062] Optionally, along the first direction, the ratio of the width W12 of the protective plate to the width W2 of the housing satisfies: 0.95≤W12 / W2≤1;

[0063] And / or, along the second direction, the ratio of the height L12 of the protective plate to the height L2 of the housing satisfies: 0.01≤L12 / L2≤0.2.

[0064] The battery provided by this utility model has two notches on the casing, which are located on one side edge of the casing along the second direction. The two notches correspond one-to-one with the two side seals, and the notches are located at the intersection of the side seals and the top seal. In other words, a notch is set at each of the top two ends of the casing, so that the side seals are located below the notches. This reduces the height of the top of the side seals and moves the top of the side seals downward, thereby avoiding the situation where the top of the side seals protrudes and interferes with other components on the top of the battery, and ensuring the normal sealing of the battery.

[0065] Moreover, this can also, to some extent, prevent the top of the side seal from protruding and easily colliding with the battery compartment, thus avoiding potential safety hazards.

[0066] Meanwhile, by setting a groove on one side edge of the cell along the second direction, the groove includes a first groove area and a second groove area, so that the first tab is located in the first groove area and the second tab is located in the second groove area. This reduces the space occupied by the first tab and the second tab in the height direction of the cell, increases the utilization rate in the height direction of the cell, and thus improves the energy density per unit volume of the cell. To a certain extent, this compensates for the energy density lost due to the gaps in the casing, thereby ensuring the energy density of the entire battery.

[0067] In addition, the grooves can also fix and protect the tabs to a certain extent, reduce the stress on the tabs when they are hit by accident, reduce the risk of the tabs breaking due to impact, thereby improving the stability of the tabs, and thus ensuring the formation of an effective flow path inside the battery, ensuring the normal use of the battery.

[0068] In other words, the battery provided by this utility model, by setting notches and grooves, not only avoids to a certain extent the situation where the top of the side seal interferes with other parts on the top of the battery or impacts the battery compartment, thus preventing safety hazards, but also improves the unit volume energy density of the battery cell, thereby ensuring the energy density of the entire battery. Furthermore, it reduces the risk of the tabs being damaged by impacts and improves the stability of the tabs. Attached Figure Description

[0069] Figure 1 This is a schematic diagram of the structure of a battery according to an embodiment of the present invention. Figure 1 ;

[0070] Figure 2 for Figure 1 A magnified view of the local structure;

[0071] Figure 3 This is a schematic diagram of the shell structure after sealing according to an embodiment of the present invention;

[0072] Figure 4 This is a schematic diagram of a partial structure of the battery according to an embodiment of the present invention. Figure 1 ;

[0073] Figure 5 This is a schematic diagram of a partial structure of the battery according to an embodiment of the present invention. Figure 2 ;

[0074] Figure 6 This is a schematic diagram of the structure of a battery according to an embodiment of the present invention. Figure 2 ;

[0075] Figure 7 This is a schematic diagram of the structure of a battery according to an embodiment of the present invention. Figure 3 ;

[0076] Figure 8 This is a schematic diagram of the structure of a battery cell according to an embodiment of the present invention;

[0077] Figure 9 This is a schematic diagram of the stacked arrangement of the first electrode, diaphragm, and second electrode according to an embodiment of the present invention. Figure 1 ;

[0078] Figure 10 This is a schematic diagram of the structure of the first electrode sheet according to an embodiment of the present invention;

[0079] Figure 11 This is a schematic diagram of the structure of the second electrode sheet according to an embodiment of the present invention;

[0080] Figure 12 This is a schematic diagram of the diaphragm structure according to an embodiment of the present invention. Figure 1 ;

[0081] Figure 13 This is a partial structural diagram of the shell, first electrode, and second electrode according to an embodiment of the present invention;

[0082] Figure 14 This is a partial structural schematic diagram of the first electrode sheet according to an embodiment of the present invention;

[0083] Figure 15 for Figure 1 A partial structural cross-sectional view along direction AA in the middle;

[0084] Figure 16This is a schematic diagram of the stacked arrangement of the first electrode, diaphragm, and second electrode according to an embodiment of the present invention. Figure 2 ;

[0085] Figure 17 This is a schematic diagram of the stacked arrangement of the first electrode, diaphragm, and second electrode according to an embodiment of the present invention. Figure 3 ;

[0086] Figure 18 This is a schematic diagram of the diaphragm structure according to an embodiment of the present invention. Figure 2 ;

[0087] Figure 19 This is a schematic diagram of the structure of a battery according to an embodiment of the present invention. Figure 4 .

[0088] The components are as follows: 1. Shell; 10. Notch; 11. Top sealing edge; 12. Side sealing edge; 13. Shell body; 14. Top sealing area; 15. Side sealing area; 16. Notch sealing area; 2. Battery cell; 20. Electrode; 21. Groove; 211. First groove area; 212. Second groove area; 22. First electrode plate; 220. First electrode plate; 221. First electrode plate foil; 222. First main electrode plate; 223. First electrode plate bundle; 224. Connecting area; 225. First notch portion; 226. First groove portion; 23. Second electrode plate; 230. Second electrode plate; 231. Second electrode plate foil; 232. Second notch portion; 233. Second groove portion; 24. Diaphragm; 241. Diaphragm notch portion; 242. Diaphragm groove portion; 25. Recessed portion; 3. Adhesive component; 4. Protective plate. Detailed Implementation

[0089] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model are within the protection scope of the present utility model.

[0090] A lithium-ion battery specifically consists of a casing and a cell. The casing covers the outside of the cell and has a top seal and side seals. The cell has tabs that extend from the top seal to the outside of the casing. If the top of the side seal protrudes, it can easily interfere with other components on the top of the battery, affecting the normal packaging of the battery. Furthermore, when the battery is impacted, the side seal may collide with the battery compartment of the equipment.

[0091] Based on this, this utility model embodiment provides a battery that provides notches at both ends of the top of the casing, with each notch corresponding to one of the two side seals of the casing. The side seals are positioned below the corresponding notches, i.e., the top of the side seals is lowered. This, to a certain extent, avoids interference or impact between the side seals and other components on the top of the battery, ensuring proper battery packaging and safety. Simultaneously, to balance the battery's energy density, grooves are provided on the cell, with the tabs located within the grooves. This reduces the space occupied by the tabs in the cell's height direction, increasing the utilization rate in that direction and thus improving the cell's energy density per unit volume. This, in turn, ensures the overall battery energy density and simultaneously improves the stability of the tabs.

[0092] The battery provided by this utility model will be described in detail below with reference to the accompanying drawings and specific embodiments:

[0093] This embodiment provides a battery, such as a lithium-ion battery. The battery can be used as a power source or energy storage unit for electronic devices, which may be, but are not limited to, mobile devices (mobile phones, laptops, tablets, etc.) and electric vehicles (e.g., pure electric vehicles, hybrid electric vehicles, electric bicycles, etc.).

[0094] Reference Figures 1 to 19 As shown, the battery provided in this embodiment includes a casing 1 and a battery cell 2. The casing 1 covers the outside of the battery cell 2.

[0095] The battery cell 2 specifically includes a first electrode 22, a second electrode 23, and a separator 24. The first electrode 22 and the second electrode 23 have opposite polarities, and the separator 24 is located between the first electrode 22 and the second electrode 23. The first electrode 22, the separator 24, and the second electrode 23 are stacked sequentially.

[0096] For example, the first electrode 22, the diaphragm 24, and the second electrode 23 can be stacked in sequence to form a core.

[0097] The battery cell 2 has tabs 20, which specifically include: a first tab 220 disposed on the first electrode 22 and a second tab 230 disposed on the second electrode 23.

[0098] For example, the first electrode 22 is the negative electrode and the second electrode 23 is the positive electrode. Of course, the first electrode 22 can also be the positive electrode and the second electrode 23 can be the negative electrode.

[0099] The housing 1 has a top sealing edge 11 and two side sealing edges 12, which are respectively located on opposite sides of the housing 1 along a first direction. The first electrode tab 220 and the second electrode tab 230 extend from the top sealing edge 11.

[0100] The first direction in this article can specifically be the width direction of the battery, as shown in the reference. Figure 1 As shown, for example, the first direction is Figure 1 The left and right directions in the middle.

[0101] The housing 1 has two notches 10 located on one edge of the housing 1 along a second direction. The second direction in this text can specifically refer to the height direction of the battery, as shown in the reference... Figure 1 As shown, for example, the second direction is Figure 1 The up and down directions in the middle.

[0102] Specifically, the notch 10 corresponds one-to-one with the side sealing edge 12, and the notch 10 is located at the intersection of the side sealing edge 12 and the top sealing edge 11.

[0103] Continue to refer to Figure 1 As shown, one notch 10 is located above the left side seal 12, and the other notch 10 is located above the right side seal 12. This positions the side seal 12 below the notch 10, thus lowering the height of the top of the side seal 12 and preventing it from protruding and interfering with other components on the top of the battery, ensuring proper battery encapsulation. Furthermore, this design also helps to mitigate the safety hazard caused by the protruding top of the side seal 12 potentially impacting the battery compartment.

[0104] For example, the two notches 10 can be arranged symmetrically along the midline of the width direction of the battery.

[0105] In specific implementation, refer to Figure 19 As shown, a protection plate 4 can be provided on the top of the battery. The first tab 220 and the second tab 230 are respectively connected to the protection plate 4 to protect the battery cell 2 from damage or explosion risks caused by abnormal conditions such as overcharging, over-discharging, and short circuits. For example, the protection plate 4 can be welded to the tab 20. After the protection plate 4 is connected to the tab 20, it can be folded along with the tab 20 to the side of the top sealing edge 11 opposite to the battery cell 2. For example, the notch 10 can effectively prevent interference between the side sealing edge 12 and the protection plate 4, thus preventing interference with normal sealing.

[0106] Meanwhile, in this embodiment, a groove 21 is provided on one side edge of the battery cell 2 along the second direction. The groove 21 specifically includes a first groove area 211 and a second groove area 212, which are arranged at intervals along the first direction. Specifically, a portion of the first tab 220 is located in the first groove area 211, and a portion of the second tab 230 is located in the second groove area 212.

[0107] By placing a portion of the first tab 220 within the first groove region 211 and a portion of the second tab 230 within the second groove region 212, the space occupied by the first tab 220 and the second tab 230 in the height direction of the cell 2 is reduced, increasing the utilization rate of the cell 2 in the height direction and thus improving the energy density per unit volume of the cell 2. This, to a certain extent, compensates for the energy density loss due to the presence of the gap 10 on the casing 1, thereby ensuring the energy density of the entire battery.

[0108] Furthermore, the first groove area 211 and the second groove area 212 can also fix and protect the first tab 220 and the second tab 230 to a certain extent, reducing the stress on the tabs when they are subjected to accidental impacts, reducing the risk of the tabs shaking or breaking due to impacts, thereby improving the stability of the tabs, and thus ensuring the formation of an effective flow path inside the battery, ensuring the normal use of the battery.

[0109] In a specific implementation, for example, the shell 1 can be an aluminum-plastic film shell, or a steel shell or other materials.

[0110] The battery provided in this embodiment has two notches 10 on the housing 1, which are located on one side edge of the housing 1 along the second direction. The two notches 10 correspond one-to-one with the two side sealing edges 12, and the notches 10 are located at the intersection of the side sealing edges 12 and the top sealing edge 11. That is, a notch 10 is provided at each of the top two ends of the housing 1, and the side sealing edges 12 are located below the notches 10. This reduces the height of the top of the side sealing edges 12 and moves the top of the side sealing edges 12 downward, thereby avoiding the situation where the top of the side sealing edges 12 protrudes and interferes with other components such as the protective plate 4 on the top of the battery, thus ensuring the normal packaging of the battery.

[0111] Moreover, this can also, to some extent, prevent the top of the side seal 12 from protruding and easily colliding with the battery compartment, thus avoiding potential safety hazards.

[0112] Meanwhile, by providing a groove 21 on one side edge of the cell 2 along the second direction, the groove 21 includes a first groove area 211 and a second groove area 212, so that part of the first tab 220 is located in the first groove area 211 and part of the second tab 230 is located in the second groove area 212. This reduces the space occupied by the first tab 220 and the second tab 230 in the height direction of the cell 2, increases the utilization rate of the cell 2 in the height direction, and thus improves the unit volume energy density of the cell 2. To a certain extent, this compensates for the energy density lost due to the presence of the gap 10 on the casing 1, thereby ensuring the energy density of the entire battery.

[0113] In addition, the groove 21 can also play a role in fixing and protecting the tab to a certain extent, reducing the stress on the tab when it is accidentally impacted, reducing the risk of the tab breaking due to impact, thereby improving the stability of the tab, and thus ensuring the formation of an effective flow path inside the battery, ensuring the normal use of the battery.

[0114] In other words, the battery provided in this embodiment, by setting the notch 10 and the groove 21, not only avoids to a certain extent the situation where the top of the side seal 12 interferes with other components on the top of the battery or collides with the battery compartment, thus preventing safety hazards, but also effectively improves the unit volume energy density of the cell 2, thereby ensuring the energy density of the entire battery. Furthermore, it reduces the risk of the tab 20 being damaged by impact and improves the stability of the tab 20.

[0115] In practice, if the size of the notch 10 is too large, it will result in a significant loss of energy density in the battery. However, if the size of the notch 10 is too small, the presence of the notch 10 will not effectively reduce the height of the top of the side seal 12, thus failing to effectively reduce the impact of the side seal 12 on the battery encapsulation.

[0116] Based on this, combined Figure 1 and Figure 2 As shown, in some embodiments, along the first direction, the width W1 of the notch 10 satisfies: 0.3mm ≤ W1 ≤ 3mm. Specifically, the first direction can be... Figure 1 The left and right directions in the image can be represented by the width of the battery.

[0117] For example, the width W1 of the notch 10 can be 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.65mm, 1.8mm, 2mm, 2.3mm, 2.6mm, 2.8mm, or 3mm.

[0118] In some embodiments, along the first direction, the ratio of the width W1 of the notch 10 to the width W2 of the housing 1 satisfies: 0.07 ≤ W1 / W2 ≤ 0.12. For example, this ratio can specifically be 0.07, 0.08, 0.09, 0.095, 0.1, 0.11, or 0.12.

[0119] By setting the width W1 of the notch 10 as described above, interference between the side seal 12 and other components on the top of the battery and impact on the battery compartment are further avoided, while also ensuring the high energy density of the battery.

[0120] Continue to combine Figure 1 and Figure 2 As shown, in some embodiments, along the second direction, the height L1 of the notch 10 satisfies: 0.3mm ≤ L1 ≤ 3mm. Specifically, the second direction here can be... Figure 1 The vertical direction in the text refers to the height of the battery.

[0121] For example, the height L1 of the notch 10 can be 0.3mm, 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.65mm, 1.8mm, 2mm, 2.3mm, 2.6mm, 2.8mm, or 3mm.

[0122] In some embodiments, along the second direction, the ratio of the height L1 of the notch 10 to the height L2 of the housing 1 satisfies: 0.05 ≤ L1 / L2 ≤ 0.1. For example, this ratio can specifically be 0.05, 0.06, 0.07, 0.075, 0.08, 0.09, or 0.1.

[0123] By setting the height L1 of the notch 10 as described above, it is possible to further prevent the top of the side seal 12 from protruding and interfering with other components on the top of the battery, and to further prevent the side seal 12 from hitting the battery compartment when the battery is impacted, while also taking into account the high energy density of the battery.

[0124] Combination Figure 1 and Figure 2 As shown, in the first feasible implementation, the width W1 of the notch 10 gradually decreases linearly in the direction toward the side seal 12. Specifically, the first direction can be... Figure 1 The left and right directions. That is to say, along the Figure 1 and Figure 2 In the direction from top to bottom, the width W1 of the notch 10 gradually decreases in a linear trend, making the cross-section of the notch 10 form a triangular structure.

[0125] This reduces the top height of the side seal 12 and ensures the battery energy density, while making the fabrication of the notch 10 easier.

[0126] Reference Figure 6 As shown, in the second feasible implementation, the notch 10 is an arc-shaped notch 10 that is recessed toward the inner cavity of the shell 1.

[0127] This reduces the top height of the side seal 12 while also reducing the stress at the notch 10 to some extent, thus preventing damage caused by excessive stress at the notch 10.

[0128] Reference Figure 7 As shown, in the third feasible implementation, along the second direction, the width W1 of the notch 10 at different locations in the first direction is equal. The first direction here specifically refers to... Figure 7 The left and right directions, the second direction is specifically as follows Figure 7The vertical direction within. Specifically, gap 10 is along... Figure 7 The width W1 is equal at different positions in the vertical direction. For example, this makes the notch 10 roughly L-shaped.

[0129] This reduces the top height of the side sealing edge 12 while making the production of the notch 10 easier.

[0130] Reference Figure 3 As shown, in some embodiments, the housing 1 specifically includes a housing body 13, a top sealing area 14, a side sealing area 15, and a notch sealing area 16.

[0131] The casing 13 covers the outside of the battery cell 2, and the top sealing area 14 is located along the second direction of the casing 13. Figure 3 On one side of the top sealing area 14 (in the vertical direction), the first tab 220 and the second tab 230 extend from the top sealing area 14. The top sealing area 14 at least seals the space between the housing 1 and the tab 20.

[0132] There are two side sealing areas 15, which are respectively located on the shell body 13 along the first direction ( Figure 3 The two sides of the top sealing area 14 (in the left and right direction) are opposite each other. There are two notch sealing areas 16, which correspond one-to-one with the side sealing areas 15 and are located between the top sealing area 14 and the corresponding side sealing area 15.

[0133] The notch sealing area 16 can form an overlapping sealing area with the corresponding top sealing area 14 and side sealing area 15.

[0134] The top sealing area 14 and the partially notched sealing area 16 are bent toward the shell body 13 to form the top sealing edge 11; the side sealing area 15 and the partially notched sealing area 16 are bent toward the shell body 13 at least once to form the side sealing edge 12.

[0135] It is understandable that after the top sealing area 14, the notch sealing area 16, and the side sealing area 15 are sealed and bent, the notch 10 can be formed on both sides of the shell 1 along the first direction.

[0136] The casing 1 is well sealed through various sealing zones, providing a sealed space for the battery cell 2 and other components, thereby ensuring the battery's high performance, safety, and long-term stability.

[0137] By bending the sealing area, the volume occupied by the sealing area is reduced, which helps to improve the volumetric energy density of the battery.

[0138] Among them, reference Figure 5 As shown, the side sealing area 15 can be bent once towards the shell body 13 to form the side sealing edge 12. (Refer to...) Figure 4As shown, the side sealing area 15 can also be bent at least twice toward the shell body 13 to form the side sealing edge 12, thereby further reducing the space occupied and further improving the energy density of the battery.

[0139] Reference Figure 4 and Figure 5 As shown, in some embodiments, the side of the side seal 12 facing the housing body 13 is connected to the housing body 13 by an adhesive 3. The adhesive 3 can be, for example, an adhesive or adhesive tape. This can improve the stability of the side seal 12 and prevent the side seal 12 from shaking or folding away from the housing body 13, thus affecting the normal use of the battery.

[0140] For example, the housing 1 includes a heat-sealing layer, a metal layer, and a nylon layer from the inside out. In a specific implementation, an adhesive 3 can also be provided at the bent end of the side sealing area 15 to prevent the metal layer inside the housing 1 from being exposed and causing a short circuit.

[0141] If the size of the top sealing area 14 is too large, it will reduce the effective usable volume of the battery and result in a loss of energy density. However, if the size of the top sealing area 14 is too small, it will result in a smaller effective sealing area and a risk of electrolyte leakage.

[0142] Based on this, refer to Figure 3 As shown, in some embodiments, along the second direction, the height L3 of the top sealing area 14 satisfies: 1mm ≤ L3 ≤ 5mm. Specifically, the second direction here can be... Figure 3 The vertical direction in the image can be, for example, the height direction of the housing 1. For example, the height L3 can be 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, or 5mm.

[0143] Combination Figure 1 and Figure 3 In some embodiments, along the second direction, the ratio of the height L3 of the top sealing area 14 to the height L2 of the housing 1 satisfies: 0.1 ≤ L3 / L2 ≤ 0.2. For example, this ratio can specifically be 0.1, 0.12, 0.15, 0.17, 0.18, or 0.2.

[0144] In some embodiments, along the first direction, the ratio of the width W3 of the top sealing area 14 to the width W2 of the housing 1 satisfies: 0.88 ≤ W3 / W2 ≤ 0.93. Specifically, the first direction can be... Figure 1 and Figure 3 The left and right directions in the middle. For example, the ratio of W3 / W2 can be 0.88, 0.89, 0.9, 0.905, 0.91, 0.92, 0.93.

[0145] By setting the size of the top sealing area 14 within the aforementioned range, not only is the area of ​​the effective sealing area guaranteed, ensuring the sealing effect of the casing 1, thereby ensuring the various performance and safety of the battery, but the battery's usable volume is also taken into account, ensuring the battery's energy density.

[0146] Continue to combine Figure 1 and Figure 3 As shown, in some embodiments, along the second direction, the relationship between the height L4 of the side sealing area 15, the height L1 of the notch 10, and the height L2 of the shell 1 can satisfy, for example, L4 = L2 - L1. Specifically, the second direction here can be... Figure 1 and Figure 3 The up and down directions.

[0147] If the size of the side sealing area 15 is too large, it will reduce the effective usable volume of the battery and result in a loss of energy density. However, if the size of the side sealing area 15 is too small, it will result in a smaller effective sealing area and a risk of electrolyte leakage.

[0148] In some embodiments, along the first direction, the width W4 of the side sealing area 15 satisfies: 1mm ≤ W4 ≤ 5mm. Specifically, the first direction can be... Figure 3 For example, the width W4 in the left and right directions can be 1mm, 2mm, 3mm, 4mm, or 5mm.

[0149] By setting the size of the side sealing area 15 within the above range, not only is the area of ​​the effective sealing area guaranteed, ensuring the sealing effect of the casing 1, thereby ensuring the various performance and safety of the battery, but also the battery's usable volume is taken into account, ensuring the battery's energy density.

[0150] Reference Figure 4 As shown, in some embodiments, along a third direction, the ratio of the thickness H2 of the side sealing edge 12 to the thickness H1 of the shell body 13 satisfies: 0.8mm ≤ H2 / H1 ≤ 0.98mm. This third direction can be, for example,... Figure 4 The vertical direction can be the thickness direction of the battery. For example, the ratio of H2 / H1 can be 0.8mm, 0.83mm, 0.86mm, 0.89mm, 0.9mm, 0.92mm, 0.95mm, or 0.98mm.

[0151] By setting the thickness of the side sealing edge 12 as described above, the sealing effect of the housing 1 is ensured, while also taking into account the energy density of the battery.

[0152] Combination Figures 1 to 3As shown, in some embodiments, the relationship between the width W5 of the notch sealing area 16 along the fourth direction, the height L1 of the notch 10 along the second direction, and the width W1 of the notch 10 along the first direction can, for example, satisfy:

[0153]

[0154] Reference Figure 3 As shown, the fourth direction here can specifically be... Figure 3 The X-direction in the middle.

[0155] If the size of the notch sealing area 16 is too large, it will reduce the effective usable volume of the battery and result in a loss of energy density. However, if the size of the notch sealing area 16 is too small, it will result in a smaller effective sealing area and a risk of electrolyte leakage.

[0156] In some embodiments, along the fifth direction, the height L5 of the notch sealing area 16 satisfies: 1mm ≤ L5 ≤ 5mm. Specifically, the fifth direction can be... Figure 3 The Z-axis. For example, the height L5 can be 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, or 5mm.

[0157] In some embodiments, the ratio of the height L5 of the notch sealing area 16 along the fifth direction to the height L2 of the housing 1 along the second direction satisfies: 0.1 ≤ L5 / L2 ≤ 0.2. For example, this ratio can be 0.1, 0.12, 0.14, 0.15, 0.17, 0.18, 0.19, or 0.2.

[0158] By setting the height L5 and width W5 of the notch sealing area 16 as described above, not only is the area of ​​the effective sealing area guaranteed, ensuring the sealing effect of the casing 1, thereby ensuring the various performance and safety of the battery, but the battery's usable volume is also taken into account, ensuring the battery's energy density.

[0159] In practice, if the distance between the battery cell 2 and the inner wall of the casing 1 is too small, it will be difficult to put the battery cell into the casing 1 and will affect the shape of the sealing area, resulting in a reduction in battery safety performance. However, if the distance between the battery cell 2 and the inner wall of the casing 1 is too large, it will reduce the effective usable space of the battery cell 2, resulting in a reduction in battery energy density. Moreover, when the battery is impacted, the battery cell 2 will shake violently, resulting in a reduction in battery safety performance.

[0160] Based on this, combined Figure 1 and Figure 2 As shown, in some embodiments, along the first direction, the distance d1 between the battery cell 2 and the inner wall of the housing 1 satisfies: 0.2mm ≤ d1 ≤ 1mm. Specifically, the first direction can be... Figure 1and Figure 2 The left and right direction, for example, the width direction of the battery. For example, d1 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 1mm.

[0161] In some embodiments, along the second direction, the distance d2 between the battery cell 2 and the inner wall of the housing 1 satisfies: 0.2mm ≤ d2 ≤ 1mm. Specifically, the second direction can be... Figure 1 and Figure 2 The vertical direction in the image represents the height of the battery. For example, d2 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 1mm.

[0162] By setting the distance between the battery cell 2 and the inner wall of the housing 1 within the aforementioned range, it ensures that the battery cell 2 can be placed inside the housing 1 while ensuring the formation of an effective sealing area, and also takes into account the energy density of the battery and the stability of the battery cell 2.

[0163] Reference Figure 8 As shown, the battery cell 2 has a recess 25 at the position corresponding to the notch 10 on the housing 1. Specifically, a recess 25 is provided on each of the two top edges of the battery cell 2, and the recess 25 corresponds one-to-one with the notch 10 on the housing 1.

[0164] This design allows the shape of the battery cell 2 to roughly match that of the casing 1. With the internal space of the casing 1 remaining unchanged, the battery cell 2 can utilize more space effectively, thereby further improving its volumetric energy density. Furthermore, compared to designs without the recessed portion 25 on the battery cell 2, this design can, to some extent, prevent the corners of the battery cell 2 from squeezing the casing 1 during charging and discharging, thus avoiding corner breakage or cracking of the casing 1 and improving battery safety.

[0165] Specifically, the first electrode 22 has a first notch 225 at the position corresponding to the notch 10; the second electrode 23 has a second notch 232 at the position corresponding to the notch 10; and the diaphragm 24 has a diaphragm notch 241 at the position corresponding to the notch 10.

[0166] That is, the first notch 225, the second notch 232, and the diaphragm notch 241 correspond to the above-mentioned recesses 25 formed on both sides of the top of the cell 2, and the recesses 25 correspond to the notches 10 of the casing 1.

[0167] Combination Figure 1 , Figure 2 and Figure 13As shown, in some embodiments, along the first direction, the relationship between the width W6 of the first notch 225, the width W1 of the notch 10, and the distance d1 between the cell 2 and the inner wall of the housing 1 can satisfy, for example, that: W6 = W1 - d1; d1 > 0. Here, the first direction specifically refers to... Figure 13 The left and right directions in the middle.

[0168] Furthermore, d1 can be specifically set as: 0.2mm≤d1≤1mm.

[0169] By setting the width of the first notch 225 as described above, the size of the notch 10 of the housing 1 after the housing 1 covers the outside of the cell 2 is ensured to maintain the energy density of the cell 2 while avoiding interference between the side seal 12 and other components.

[0170] Combination Figure 1 , Figure 2 and Figure 13 As shown, along the second direction, the relationship between the height L6 of the first notch 225, the height L1 of the notch 10, and the distance d2 between the cell 2 and the inner wall of the casing 1 can satisfy, for example, that: L6 = L1 - d2; d2 > 0. Specifically, the second direction here is... Figure 13 The up and down directions in the middle.

[0171] Furthermore, d2 can be specifically set as: 0.2mm≤d2≤1mm.

[0172] By setting the height of the first notch 225 as described above, the size of the notch 10 of the housing 1 after the housing 1 covers the outside of the cell 2 is guaranteed to ensure the energy density of the cell 2 while avoiding interference between the side seal 12 and other components.

[0173] Continue to refer to Figure 13 As shown, in some embodiments, the first electrode 22 is a negative electrode and the second electrode 23 is a positive electrode. In this case, the projected edge of the second electrode 23 on the first electrode 22 is located within the area enclosed by the first electrode 22. That is to say, while avoiding interference and impact from the side sealing edge and improving the energy density of the battery, it ensures that the negative electrode can effectively cover the positive electrode, avoiding lithium plating, and thus ensuring the electrical performance of the battery.

[0174] Specifically, along the first direction (which can be...) Figure 13 (in the left and right directions), the width W7 of the second notch 232, the width W1 of the notch 10, the distance d1 between the cell 2 and the inner wall of the casing 1, and the projection of the second electrode 23 onto the first electrode 22 on one side edge in the first direction (e.g., in the left and right directions), the distance W7 of the second notch 232, the distance W1 of the notch 10, the distance d1 between the cell 2 and the inner wall of the casing 1, and the distance d1 between the projection of the second electrode 23 onto the first electrode 22 on one side edge in the first direction (e.g., in the left and right directions). Figure 13 The left edge corresponding to the second electrode 23 in the first direction (e.g., the side edge of the first electrode 22 along the first direction) and the left edge corresponding to the second electrode 23 in the first direction (e.g., the left edge of the second electrode 23 in the first direction) and the right edge corresponding to the first electrode 22 along the first direction (e.g., the left edge of the second electrode 23 in the first direction) Figure 13 The relationship between the distance s1 between the left edge of the first pole piece and the pole piece can be satisfied, for example, as follows: W7 = W1 - d1 - s1; d1 > 0, s1 > 0.

[0175] Furthermore, d1 can be specifically set as: 0.2mm≤d1≤1mm.

[0176] In some embodiments, s1 can be specifically set to: 0.3mm < s1 < 1mm. For example, s1 can be 0.32mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, or 0.95mm. This setting further ensures effective coverage of the positive electrode by the negative electrode, preventing lithium plating.

[0177] Along the second direction (specifically, it can be...) Figure 13 (up and down direction), the height L7 of the second notch 232, the height L1 of the notch 10, the distance d2 between the cell 2 and the inner wall of the casing 1, and the projection of the second electrode 23 onto the first electrode 22 on one side edge in the second direction (e.g., in the vertical ...). Figure 13 The upper edge corresponding to the second electrode 23 in the middle) and the side edge of the first electrode 22 along the second direction (for example, the ... are the same as the upper edge of the first electrode 22 along the second direction. Figure 13 The relationship between the distance s2 between the upper edge of the first pole piece and the pole piece can be satisfied, for example, as follows: L7 = L1 - d2 - s2; d2 > 0, s2 > 0.

[0178] Furthermore, d2 can be specifically set as: 0.2mm≤d2≤1mm.

[0179] In some embodiments, s2 can be specifically set to: 0.3mm < s2 < 1mm. For example, s2 can be 0.32mm, 0.4mm, 0.5mm, 0.6mm, 0.8mm, or 0.97mm. This setting further ensures effective coverage of the positive electrode by the negative electrode, preventing lithium plating.

[0180] By setting the size of the second notch 232 as described above, the size of the notch 10 of the housing 1 after the housing 1 covers the outside of the cell 2 is such that it avoids interference between the side seal 12 and other components, and not only avoids lithium plating caused by insufficient coverage of the positive electrode by the negative electrode, but also ensures the energy density of the battery to a certain extent.

[0181] Reference Figure 1 and Figure 9 , Figure 6 and Figure 16 , Figure 7 and Figure 17As shown, the shapes of the first notch 225, the second notch 232, and the separator notch 241 can be specifically matched with the notch shape of the housing 1, thereby further improving the energy density of the battery.

[0182] Combination Figures 9 to 15 As shown, in some embodiments, the first tab 220 includes a first main tab 222 and a first tab foil 221 extending from one side of the first electrode 22 along a second direction. For example, the first tab foil 221 can be formed at a location by washing away the active material layer at a predetermined position on the first electrode 22.

[0183] All first electrode foils 221 are connected to the first main electrode tab 222. At least a portion of the first electrode foil 221 is located within the first groove area 211, and the first main electrode tab 222 extends from the top sealing edge 11.

[0184] Reference Figure 15 As shown (for illustrative purposes only), Figure 15 Only the first electrode 22 of the cell 2 is shown. In a specific implementation, the first electrode tab foils 221 on all the first electrode tabs 22 are connected to form the first electrode tab bundle 223. The first electrode tab bundle 223 is connected to the first main electrode tab 222, for example, by welding.

[0185] Accordingly, the second tab 230 includes a second main tab and a second tab foil 231 extending from one side of the second electrode 23 along a second direction, all of which are connected to the second main tab. For example, the second tab foil 231 can be formed at a location by washing away the active material layer at a predetermined position on the second electrode 23.

[0186] At least a portion of the second electrode tab foil 231 is located within the second groove region 212, and the second main electrode tab extends from the top sealing edge 11. Exemplarily, the second electrode tab foils 231 on all the second electrode sheets 23 are connected to form a second electrode tab bundle, which is connected to the second main electrode tab, for example, by welding.

[0187] By placing at least a portion of the first tab foil 221 and at least a portion of the second tab foil 231 within the corresponding groove area, the space occupied by the corresponding tab foil in the height direction of the cell 2 is reduced, thereby further reducing the space occupied by the entire first tab 220 and second tab 230 in the height direction of the cell 2, thereby increasing the utilization rate in the height direction of the cell 2 and improving the energy density per unit volume of the cell 2.

[0188] Furthermore, in some embodiments, at least a portion of the connection area 224 between all the first tab foils 221 and the first main tab 20 is located within the first groove area 211.

[0189] This design further reduces the space occupied by the first tab 220 in the height direction of the cell 2, thereby increasing the energy density of the cell 2. Moreover, this design effectively reduces the risk of the first tab 220 shaking or even breaking when impacted, improving the battery's resistance to drops and impacts.

[0190] In some embodiments, at least a portion of the connection area between all the second electrode foils 231 and the second main electrode is located within the second groove area 212.

[0191] This design further reduces the space occupied by the second tab 230 in the height direction of the cell 2, thereby further improving the energy density of the cell 2. Moreover, this design can effectively reduce the risk of the second tab 230 shaking or even breaking when impacted, thus improving the battery's resistance to drops and impacts.

[0192] For example, the first electrode 22 will be used as an example for further explanation. Please refer to [link / reference]. Figure 15 As shown, all the first tab foils 221 are gathered towards the cell 2 to form a first tab bundle 223. The first tab bundle 223 is bent, and the bent portion is located in the groove 21. One end of the first main tab 222 is bent and connected to the first tab bundle 223. The connection area 224 between the two is located in the groove 21. The other end of the first main tab 222 extends from the top sealing edge 11. That is, the tab bending process further reduces the space occupied by the tabs in the height direction of the cell, thereby further improving the energy density per unit volume of the cell.

[0193] By placing the bending area and the connection area 224 of the tab 20 within the groove 21, the risk of the tab 20 shaking or even breaking when impacted is further reduced, and the battery's resistance to drops and impacts is improved.

[0194] Of course, in other implementations, all the first tab foils 221 can also be gathered toward the middle of the cell 2 to form a first tab bundle 223, and then connected to the first main tab 222.

[0195] In addition, in other implementations, the first tab bundle 223 and the first main tab 222 can also be extended directly toward the top of the battery without bending, i.e., the tabs are straight out.

[0196] The second electrode 230 can be configured in the same way as the first electrode 220 described above, and will not be repeated here.

[0197] In practice, if the size of the connection area of ​​each of the above tabs is too large, it will cause the connection area to occupy too much space on the top of the cell 2, affecting the energy density. However, if the size of each of the above connection areas is too small, it will cause the current conduction capacity of the connection area to be poor, resulting in excessive temperature rise during cycling.

[0198] Based on this, the explanation will take the connection region 224 corresponding to the first electrode as an example, combined with... Figure 14 and Figure 15 As shown, in some embodiments, along the first direction, the width W8 of the connecting area 224 satisfies: 4mm ≤ W8 ≤ 12mm. Specifically, the first direction can be... Figure 14 The width W8 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, or 12mm.

[0199] Along the second direction, the height L8 of the connecting area satisfies: 0.3mm ≤ L8 ≤ 5mm. Specifically, the second direction here is... Figure 14 The vertical direction within. For example, the height L8 can be 0.3mm, 0.5mm, 0.8mm, 1mm, 2mm, 2.65mm, 3mm, 4mm, or 5mm.

[0200] The specific dimensions of the connection area corresponding to the second electrode 23 can be the same as the dimensions of the connection area 224 corresponding to the first electrode 22, and will not be described in detail here.

[0201] By setting the dimensions of the connection area 224 as described above, not only is the energy density of the battery cell guaranteed, but the current conduction capacity of the tab is also improved, thus avoiding excessive temperature rise during cycling.

[0202] If the distance between each connection area and the groove wall of the corresponding groove area is too small, it will result in the loss of the active material layer when the tab foil is connected to the corresponding main tab, or it will result in the incorporation of active material into the connection area, leading to a poor solder joint. However, if the distance between the connection area and the groove wall of the corresponding groove area is too large, it will result in the effective usable volume of the cell 2 being too small, causing the energy density of the cell 2 to decrease.

[0203] Based on this, refer to Figure 14 As shown, in some embodiments, along the first direction, the distance D1 between each connecting area 224 and the groove wall of the corresponding recess area satisfies: 0.5mm ≤ D1 ≤ 3mm. Specifically, the first direction can be... Figure 14 The left and right directions. For example, the distance D1 can be 0.5mm, 0.8mm, 1mm, 1.75mm, 2mm, or 3mm.

[0204] For example, taking the connection area 224 corresponding to the first electrode 22 as an example, the distance D1 can specifically be the distance between the connection area 224 and the groove wall of the first groove portion 226.

[0205] This setup not only ensures an effective and stable connection between the tab foil and the corresponding main tab, but also improves the energy density of cell 2.

[0206] If the distance between each connection area and the bottom of the groove area is too large, it will result in more idle space at the head of the cell 2, affecting the battery energy density; however, if the distance between the connection area and the bottom of the groove area is too small, it will cause damage to the surrounding active material layer, or the connection area may be prone to being mixed with the active material layer, resulting in poor soldering.

[0207] Based on this, in some embodiments, along the second direction, the distance D2 between each connecting area 224 and the bottom of the groove area satisfies: 0.5mm ≤ D2 ≤ 2mm. Specifically, the second direction here can be... Figure 14 The vertical direction within. For example, the distance D2 can be 0.5mm, 0.8mm, 1mm, 1.25mm, 1.5mm, or 2mm.

[0208] For example, taking the connection area 224 corresponding to the first electrode 22 as an example, the distance D2 is specifically the distance between the connection area 224 and the bottom of the groove of the first groove 226.

[0209] This design ensures effective connection between the tab foil and the corresponding main tab while also improving the energy density of cell 2.

[0210] Reference Figures 9 to 12 As shown, in a specific implementation, the first electrode 22 has two first grooves 226 on one side along the second direction, and the first tab foil 221 is located in one of the first grooves 226. The diaphragm 24 has a diaphragm groove 242 at a position corresponding to the first grooves 226. The second electrode 23 has two second grooves 233 on one side along the second direction, with each second groove 233 corresponding to one of the first grooves 226. One of the second grooves 233 corresponds to the first tab foil 221, and the second tab foil 231 is located in the other second groove 233.

[0211] Along a third direction, a first groove region 211 is defined by a corresponding set of first groove portions 226, second groove portions 233, and diaphragm groove portions 242, and a second groove region 212 is defined by a corresponding set of first groove portions 226, second groove portions 233, and diaphragm groove portions 242. Specifically, this third direction refers to... Figure 9 The YY direction in the equation can specifically refer to the thickness direction of the battery.

[0212] It is understood that a first tab foil 221 is provided in one of the first groove portions 226 on the first electrode 22, and a second groove portion 233 on the second electrode 23 corresponds to the first tab foil 221 and is used to avoid the first tab foil 221, so that all the first tab foils 221 on the first electrode 22 are close to one side or the middle of the cell 2 to form a first tab bundle 223.

[0213] Correspondingly, a second tab foil 231 is provided in one of the second groove portions 233 on the second electrode 23, and a second first groove portion 226 on the first electrode 22 is provided corresponding to the second tab foil 231 to avoid the second tab foil 231, so that all the second tab foils 231 on the second electrode 23 face one side or the middle of the cell 2 to connect and form a second tab bundle.

[0214] If the groove width of the first groove portion 226 is too small, it will affect the effective accommodation of the tab 20 by the first groove portion 226, thus affecting the improvement of energy density; however, if the groove width of the first groove portion 226 is too large, it will reduce the effective usable volume of the cell 2, which will also affect the energy density.

[0215] Based on this, refer to Figure 14 As shown, in some embodiments, along the first direction, the groove width W9 of the first groove portion 226 satisfies: 5mm ≤ W9 ≤ 15mm. The first direction here specifically refers to... Figure 14 The left and right directions within the slot. For example, the slot width W9 can be 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, or 15mm.

[0216] Along the first direction, the ratio of the width W10 of the first tab foil 221 to the groove width W9 of the first groove portion 226 satisfies: 0.8 ≤ W10 / W9 ≤ 0.95. For example, this ratio can specifically be 0.8, 0.82, 0.85, 0.87, 0.89, 0.9, 0.92, or 0.95.

[0217] By setting the groove width of the first groove portion 226 as described above, not only is the effective accommodation of the first tab foil 221 and the connection area 224 by the first groove portion 226 guaranteed, but the improvement of battery energy density is also taken into account.

[0218] Reference Figure 14 As shown, in some embodiments, along the second direction, the groove depth L9 of the first groove portion 226 satisfies: 2mm ≤ L9 ≤ 6mm. Specifically, the second direction here is... Figure 14 The vertical direction within the groove. For example, the groove depth L9 can be 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, or 6mm.

[0219] Along the second direction, the ratio between the groove depth L9 of the first groove portion 226 and the height L2 of the housing 1 satisfies: 0.1≤L9 / L2≤0.25. For example, this ratio can specifically be 0.1, 0.12, 0.15, 0.165, 0.18, 0.2, 0.22, or 0.25.

[0220] By setting the groove depth L9 of the first groove portion 226 as described above, the energy density of the cell 2 is further ensured while effectively accommodating the electrode tab.

[0221] In some embodiments, the first electrode 22 is a negative electrode and the second electrode 23 is a positive electrode. In this case, the projected edge of the second electrode 23 on the first electrode 22 can be located within the area enclosed by the first electrode 22. That is, the negative electrode effectively covers the positive electrode, thereby reducing the risk of lithium plating.

[0222] Specifically, in combination Figure 11 and Figure 14 As shown, in some embodiments, along the first direction, the relationship between the groove width W11 of the second groove portion 233 and the groove width W9 of the first groove portion 226 can satisfy: 0.3mm < W11 - W9 < 1mm. For example, the difference between the groove width W11 of the second groove portion 233 and the groove width W9 of the first groove portion 226 can specifically be 0.31mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 0.99mm.

[0223] This design effectively accommodates the tabs to increase energy density while reducing the risk of lithium plating.

[0224] Along the second direction, the relationship between the groove depth L11 of the second groove portion 233 and the groove depth L9 of the first groove portion 226 satisfies: 0.3mm < L9 - L11 < 1mm. For example, the difference between the groove depth L11 of the second groove portion 233 and the groove depth L9 of the first groove portion 226 can specifically be 0.31mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, or 0.99mm.

[0225] This design effectively accommodates the tabs to increase energy density while reducing the risk of lithium plating.

[0226] For the setting of the diaphragm groove 242 on the diaphragm 24, refer to Figure 12As shown, in one feasible implementation, the area of ​​the diaphragm 24 corresponding to the first groove 226 can be cut out to form a diaphragm groove 242, thereby avoiding the corresponding tab foil. This implementation can be combined with the above-described tab folding process. Of course, it can also be combined with a direct tab output process.

[0227] In this implementation, in order to ensure that the separator 24 effectively separates the positive and negative electrodes, the projection of the negative electrode on the separator 24 can be located within the area enclosed by the edge of the separator 24, so as to ensure that the separator 24 effectively covers and protects the negative and positive electrodes. For example, along the first direction, the distance between the projection of one side edge of the separator groove 242 and one side edge of the negative electrode on the separator 24 can be set between 0.3mm and 5mm to further ensure that the separator 24 covers and protects the positive and negative electrodes.

[0228] Reference Figure 18 As shown, in another feasible implementation, a cut can be made at the edge of the diaphragm 24 corresponding to the tab foil to form the aforementioned diaphragm groove 242. In this implementation, the connection between the tab foil and the main tab is located outside the groove 21 of the cell. To achieve protection of the tab 20 and improve energy density, a tab bending process can be used. In addition, processes such as riveting welding and pressure welding can be used to weld the diaphragm 24 and the tab foil together.

[0229] Reference Figure 19 As shown, in some embodiments, the projection of the protective plate 4 in the first direction overlaps with the projection of the notch 10 in the first direction. Here, the first direction can be... Figure 19 The left and right directions in the middle.

[0230] In other words, the protective plate 4 extends above the notch 10, so that the protective plate 4 can provide a certain degree of protection for the side sealing edge 12, etc.

[0231] Combination Figure 1 and Figure 19 As shown, in some embodiments, along the first direction, the ratio of the width W12 of the protective plate 4 to the width W2 of the housing 1 satisfies: 0.95 ≤ W12 / W2 ≤ 1. This ratio can specifically be 0.95, 0.96, 0.97, 0.98, 0.99, or 1. For example, the protective plate 4 can be set to have the same width as the battery housing.

[0232] By setting the width of the protection plate 4 as described above, if the battery is impacted, the side seal 12 will contact the protection plate 4 first, which can greatly alleviate the situation where the top of the side seal 12 impacts the battery compartment and causes damage to the battery compartment, thus improving the battery's impact resistance.

[0233] In some embodiments, along the second direction, the ratio of the height L12 of the protective plate 4 to the height L2 of the housing 1 satisfies: 0.01 ≤ L12 / L2 ≤ 0.2. Specifically, the second direction here refers to... Figure 19 The vertical direction can specifically refer to the height direction of the battery. For example, the ratio can be 0.01, 0.02, 0.04, 0.07, 0.08, 0.1, 0.13, 0.15, 0.18, or 0.2.

[0234] By setting the height of the protection board 4 within the above range, the protection effect of the protection board 4 on the battery cell 2 is guaranteed, while avoiding the situation where the protection board 4 occupies too much space at the head of the battery cell 2, which would lead to a decrease in energy density.

[0235] The battery provided in this embodiment can be manufactured by the following steps: ingredient preparation, coating, rolling, slitting, cleaning, welding, and packaging.

[0236] For example, after the process before slitting, the electrode sheet with a notch 10 at the top corner and a groove 21 at the top is obtained. After the corresponding tab foil is cleaned out by means of scraper or laser, the tab foil on each electrode sheet is welded to obtain the bare cell.

[0237] The packaging shell is punched and sealed according to the bare cell. Bending is set on the sealing edges on both sides of the battery as required, and the tabs are connected to the protection board to obtain the final battery product.

[0238] In this document, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection or an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. Furthermore, the terms "upper," "lower," "left," "right," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0239] In this document, relational terms such as “first” and “second” are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0240] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications or equivalent substitutions made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A battery, characterized in that, It includes a housing and a battery cell, with the housing covering the outside of the battery cell; The battery cell includes a first electrode, a second electrode, and a separator disposed between the first electrode and the second electrode; the first electrode and the second electrode have opposite polarities, and the first electrode, the separator, and the second electrode are stacked in sequence. The first electrode plate is provided with a first electrode tab, and the second electrode plate is provided with a second electrode tab; The housing has a top sealing edge and two side sealing edges, the two side sealing edges being respectively disposed on opposite sides of the housing along a first direction; the first electrode lug and the second electrode lug extend from the top sealing edge; The housing has two notches, which are located on one side edge of the housing along the second direction. The notches correspond one-to-one with the side sealing edge, and the notches are located at the intersection of the side sealing edge and the top sealing edge. The battery cell has a groove on one side edge along the second direction. The groove includes a first groove area and a second groove area, and the first groove area and the second groove area are arranged at intervals along the first direction. The first electrode tab is located within the first groove area, and the second electrode tab is located within the second groove area.

2. The battery according to claim 1, characterized in that, Along the first direction, the width W1 of the notch satisfies: 0.3mm≤W1≤3mm; And / or, along the first direction, the ratio of the width W1 of the notch to the width W2 of the housing satisfies: 0.07 ≤ W1 / W2 ≤ 0.12; And / or, along the second direction, the height L1 of the notch satisfies: 0.3mm≤L1≤3mm; And / or, along the second direction, the ratio of the height L1 of the notch to the height L2 of the housing satisfies: 0.05≤L1 / L2≤0.

1.

3. The battery according to claim 1, characterized in that, The notch is an arc-shaped notch recessed toward the inner cavity of the shell; Alternatively, the width of the notch in the first direction gradually decreases linearly in the direction toward the side seal edge; Alternatively, along the second direction, the width of the notch is equal at different locations in the first direction.

4. The battery according to claim 1, characterized in that, The shell includes a shell body, a top sealing area, a side sealing area, and a notch sealing area; The casing body covers the outside of the battery cell, the top sealing area is located on one side of the casing body along the second direction, and the first tab and the second tab extend from the top sealing area; There are two side sealing areas, and the two side sealing areas are located on opposite sides of the shell body along the first direction; There are two notch sealing areas, each corresponding to a side sealing area, and located between the top sealing area and the corresponding side sealing area. The top sealing area and part of the notch sealing area are bent toward the shell body to form the top sealing edge; The side sealing area and part of the notch sealing area are bent at least once toward the shell body to form the side sealing edge.

5. The battery according to claim 4, characterized in that, Along the first direction, the ratio of the width W3 of the top sealing area to the width W2 of the shell satisfies: 0.88≤W3 / W2≤0.93; And / or, along the second direction, the height L3 of the top sealing area satisfies: 1mm≤L3≤5mm; And / or, along the second direction, the ratio of the height L3 of the top sealing area to the height L2 of the shell satisfies: 0.1≤L3 / L2≤0.

2.

6. The battery according to claim 4, characterized in that, Along the first direction, the width W4 of the side sealing area satisfies: 1mm≤W4≤5mm; And / or, along a third direction, the ratio of the thickness H2 of the side seal to the thickness H1 of the shell body satisfies: 0.8mm≤H2 / H1≤0.98mm; And / or, the side of the side seal facing the shell body is connected to the shell body by an adhesive.

7. The battery according to claim 4, characterized in that, Along the fifth direction, the height L5 of the notch sealing area satisfies: 1mm≤L5≤5mm; And / or, the ratio of the height L5 of the notch sealing area along the fifth direction to the height L2 of the shell along the second direction satisfies: 0.1≤L5 / L2≤0.

2.

8. The battery according to claim 1, characterized in that, Along the first direction, the distance d1 between the battery cell and the inner wall of the housing satisfies: 0.2mm≤d1≤1mm; And / or, along the second direction, the distance d2 between the cell and the inner wall of the housing satisfies: 0.2mm≤d2≤1mm.

9. The battery according to any one of claims 1 to 8, characterized in that, The first electrode has a first notch at a position corresponding to the notch; The second electrode has a second notch at the position corresponding to the notch; The diaphragm has a diaphragm notch at the position corresponding to the notch.

10. The battery according to claim 9, characterized in that, The projection edge of the second electrode on the first electrode is located within the area enclosed by the first electrode; The distance s1 between one edge of the projection of the second electrode onto the first electrode in the first direction and one edge of the first electrode along the first direction satisfies: 0.3mm < s1 < 1mm; And / or, the distance s2 between one edge of the projection of the second electrode onto the first electrode in the second direction and one edge of the first electrode along the second direction satisfies: 0.3mm < s2 < 1mm.

11. The battery according to any one of claims 1 to 8, characterized in that, The first electrode tab includes a first main electrode tab and a first electrode tab foil extending from one side of the first electrode plate along the second direction, and all the first electrode tab foils are connected to the first main electrode tab; The second electrode tab includes a second main electrode tab and a second electrode tab foil extending from one side of the second electrode plate along the second direction, all of the second electrode tab foils being connected to the second main electrode tab; At least a portion of the first electrode foil is located within the first groove region, and at least a portion of the second electrode foil is located within the second groove region; the first main electrode and the second main electrode extend from the top sealing edge, respectively.

12. The battery according to claim 11, characterized in that, At least a portion of the connection area between all the first electrode foils and the first main electrode is located within the first groove area; At least a portion of the connection area between all the second electrode foils and the second main electrode is located within the second groove area.

13. The battery according to claim 12, characterized in that, Along the first direction, the width W8 of each of the connecting areas satisfies: 4mm≤W8≤12mm; And / or, along the second direction, the height L8 of each of the connecting areas satisfies: 0.3mm≤L8≤5mm; And / or, along the first direction, the distance D1 between each of the connecting areas and the groove wall of the groove area satisfies: 0.5mm≤D1≤3mm; And / or, along the second direction, the distance D2 between each of the connecting areas and the bottom of the groove area satisfies: 0.5mm≤D2≤2mm.

14. The battery according to claim 11, characterized in that, The first electrode has two first grooves on one side along the second direction, and the first electrode tab foil is located in one of the first grooves; The diaphragm is provided with a diaphragm groove at a position corresponding to the first groove. The second electrode has two second grooves on one side along the second direction. The second grooves correspond one-to-one with the first grooves, and one of the second grooves corresponds to the first electrode foil. The second electrode foil is located in the other second groove. Along a third direction, a first groove region is defined by a corresponding group of the first groove portion, the second groove portion, and the diaphragm groove portion, and a second groove region is defined by a corresponding other group of the first groove portion, the second groove portion, and the diaphragm groove portion.

15. The battery according to claim 14, characterized in that, Along the first direction, the groove width W9 of the first groove portion satisfies: 5mm≤W9≤15mm; And / or, along the second direction, the groove depth L9 of the first groove portion satisfies: 2mm≤L9≤6mm; And / or, along the first direction, the ratio of the width W10 of the first tab foil to the groove width W9 of the first groove portion satisfies: 0.8≤W10 / W9≤0.95; And / or, along the second direction, the ratio between the groove depth L9 of the first groove portion and the height L2 of the housing satisfies: 0.1≤L9 / L2≤0.

25.

16. The battery according to claim 14, characterized in that, The projection edge of the second electrode on the first electrode is located within the area enclosed by the first electrode; Along the first direction, the relationship between the groove width W11 of the second groove and the groove width W9 of the first groove satisfies: 0.3mm < W11 - W9 < 1mm; And / or, along the second direction, the relationship between the groove depth L11 of the second groove and the groove depth L9 of the first groove satisfies: 0.3mm < L9 - L11 < 1mm.

17. The battery according to any one of claims 1 to 8, characterized in that, The battery also includes a protection board, which is located on the side of the top seal that is away from the battery cell, and the first tab and the second tab are respectively connected to the protection board; The projection of the protective plate in the first direction overlaps with the projection of the notch in the first direction.

18. The battery according to claim 17, characterized in that, Along the first direction, the ratio of the width W12 of the protective plate to the width W2 of the housing satisfies: 0.95≤W12 / W2≤1; And / or, along the second direction, the ratio of the height L12 of the protective plate to the height L2 of the housing satisfies: 0.01≤L12 / L2≤0.2.

Images