A battery

Abstract

The present invention relates to the technical field of new energy batteries, and discloses a battery comprising: a tab disposed at at least one end of a cell body along a first direction; a transition piece comprising a first connecting portion and a second connecting portion, wherein the first connecting portion is located on one side of the cell body in the first direction, the first connecting portion is connected to the tab and forms a first connecting mark, and the second connecting portion is located on one side of the cell body in the second direction, the first connecting portion and the second connecting portion are connected to each other and form a transition portion at the connection; a pole assembly is connected to the second connecting portion; in the second direction, the transition portion has a dimension a mm, and the distance between the edge of the second connecting portion facing away from the cell body and the first connecting mark is h mm, satisfying the following condition: 1≤h‑a≤14. The present invention provides a battery that, by limiting the overcurrent path on the transition piece, ensures that overcurrent requirements are met, controls heat generation in the overcurrent area, and improves the charging and discharging performance and safety of the battery.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy batteries, and in particular to a battery. Background Art

[0002] For some batteries, the tabs of the battery cells are located on the sides of the battery, while the terminal assembly is located at the top of the battery. The tabs and terminal assembly are connected by an adapter. In this structure, if the battery is charged at a high rate, the overcurrent area of ​​the adapter will generate severe heat, affecting the battery's charge and discharge performance. Summary of the Invention

[0003] The purpose of the present invention is to provide a battery to improve the charging and discharging performance of the battery.

[0004] In order to achieve the above object, the present invention provides a battery comprising:

[0005] Battery cell body;

[0006] a tab, which is provided at at least one end of the battery cell body along the first direction;

[0007] The adapter includes a first connecting portion and a second connecting portion, wherein the first connecting portion is located on one side of the battery cell body in the first direction, the first connecting portion is connected to the tab and forms a first connecting mark, and the second connecting portion is located on one side of the battery cell body in the second direction, the first connecting portion and the second connecting portion are connected to each other and form a transition portion at the connection;

[0008] a pole assembly connected to the second connecting portion;

[0009] In the second direction, the size of the transition portion is a mm, the distance between the plane where the edge of the second connecting portion faces away from the battery cell body and the first connecting mark is h mm, and 1≤h-a≤14 is satisfied.

[0010] The present invention provides a battery, which has the following advantages compared with the prior art:

[0011] The battery of the present invention includes a battery cell body, a pole ear, a adapter plate and a pole column assembly. The pole ear is arranged on the battery cell body. The adapter plate includes a first connecting part and a second connecting part. The first connecting part connects the pole ear to form a first connecting mark, and the second connecting part connects the pole column assembly. The first connecting part and the second connecting part form a transition part. By limiting the distance between the first connecting mark and the transition part, the overcurrent path on the adapter plate is limited, ensuring that the overcurrent demand is met, controlling the heat generation in the overcurrent area, and improving the charging and discharging performance of the battery and the battery safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of the structure of a battery according to an embodiment of the present invention.

[0013] Figure 2 Schematic diagram of the interior of a battery according to an embodiment of the present invention.

[0014] Figure 3 Schematic diagram of a battery cell body and a transition piece according to an embodiment of the present invention.

[0015] Figure 4 yes Figure 3 Enlarged schematic diagram of point A in the middle.

[0016] Figure 5 2 is a schematic structural diagram of an adapter according to an embodiment of the present invention.

[0017] Figure 6 Schematic diagram of an adapter according to an embodiment of the present invention.

[0018] Figure 7 Schematic diagram of another adapter according to an embodiment of the present invention.

[0019] Figure 8 It is a schematic diagram of an adapter corresponding to the full-tab structure of an embodiment of the present invention.

[0020] Figure 9 It is a schematic diagram of another adapter corresponding to the full-tab structure of an embodiment of the present invention.

[0021] Figure 10 It is a schematic diagram of an adapter corresponding to the non-full-tab structure of an embodiment of the present invention.

[0022] Figure 11 Schematic diagram of another adapter corresponding to the non-full tab structure of an embodiment of the present invention.

[0023] Figure 12 The present invention relates to an assembly structure of a tab and a switching piece.

[0024] Figure 13 This is another assembly structure of a tab and a switching piece according to an embodiment of the present invention.

[0025] In the figure, 1. Battery body; 2. Tab; 3. Adapter; 4. Post assembly;

[0026] 21. First connection seal; 22. Second connection seal;

[0027] 31. First connecting portion; 32. Second connecting portion; 33. Transition portion;

[0028] X, first direction; Z, second direction; Y, third direction. DETAILED DESCRIPTION

[0029] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "back," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0031] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0032] Furthermore, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0033] For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] Please refer to Figure 1 and Figure 2 A battery according to an embodiment of the present invention includes a cell body 1, a tab 2, a transfer sheet 3, and a pole assembly 4.

[0035] In this embodiment, the battery is a rectangular body, and the battery shell is also a rectangular body. A receiving cavity is provided inside the shell, and the receiving cavity is used to place the battery cell.

[0036] The tab 2 is disposed at at least one end of the cell body 1 along the first direction X.

[0037] The battery cell body 1 achieves charging and discharging via positive and negative tabs. The electrode sheet comprises a current collector and an active material layer, with the active material layer coated on the surface of the current collector. For positive electrode sheets, the current collector can be made of aluminum, and the active material layer can be made of materials such as lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. For negative electrode sheets, the current collector can be made of copper, and the active material layer can be made of materials such as carbon or silicon.

[0038] The first direction X, the second direction Z, and the third direction Y intersect in pairs. In this embodiment, the length of the battery is the first direction X, the height of the battery is the second direction Z, and the width of the battery is the third direction Y. The first direction X, the second direction Z, and the third direction Y are perpendicular to each other. The perpendicular state refers to a state with an angle of 85° to 95°.

[0039] Please refer to Figure 3 and Figure 4 The adapter 3 includes a first connecting portion 31 and a second connecting portion 32. The first connecting portion 31 is located on one side of the battery cell body 1 in the first direction X. The first connecting portion 31 is connected to the pole ear 2 and forms a first connecting mark 21. The second connecting portion 32 is located on one side of the battery cell body 1 in the second direction Z. The first direction X and the second direction Z are perpendicular to each other. The first connecting portion 31 and the second connecting portion 32 are connected to each other and form a transition portion 33 at the connection.

[0040] In this embodiment, please refer to Figure 5 The adapter plate 3 has an L-shaped structure, the first connecting portion 31 and the second connecting portion 32 are both plate-shaped, and the transition portion 33 forms an arc-shaped corner between the first connecting portion 31 and the second connecting portion 32.

[0041] The first connection portion 31 corresponds to the side surface of the cell body 1 and is laser welded to the tab 2 . The first connection mark 21 is the weld mark formed by welding.

[0042] The pole assembly 4 is connected to the second connecting portion 32 .

[0043] The second connecting portion 32 corresponds to the top surface of the battery cell body 1. By providing the adapter 3, the pole assembly 4 and the tab 2 are electrically connected.

[0044] The electrode assembly 4 is used to electrically connect the battery to external devices. It is divided into a positive electrode assembly 4 and a negative electrode assembly 4, each with different polarities. Each battery can have multiple positive or negative electrode assemblies 4. In this embodiment, one positive electrode assembly 4 and one negative electrode assembly 4 are provided. In actual production implementation, the number and position of the electrode assembly 4 can be adjusted as needed.

[0045] In the second direction Z, the transition portion 33 has a dimension a mm, and the distance between the plane of the edge of the second connection portion 32 facing away from the battery cell body 1 and the first connection mark 21 is h mm, satisfying the following relationship: 1 ≤ h - a ≤ 14. Preferably, ha can be 1, 3, 5.5, 8, 10.7, 12, 14, etc.

[0046] By limiting the distance between the first connection mark 21 and the transition portion 33, the overcurrent path on the adapter 3 is limited, ensuring that the overcurrent requirements are met, controlling the heat generation in the overcurrent area, and improving the battery's charge and discharge performance and battery safety. If the value of ha is too large, the path between the first connection mark 21 and the pole assembly 4 is large, and the overcurrent path of the first connection mark 21 on the adapter 3 is too long, resulting in serious heat generation in the first connection mark 21, affecting the battery's charge and discharge performance and safety performance; if the value of ha is too small, the first connection mark 21 will be too close to the transition portion 33. When welding the tab 2 and the first connection portion 31, the position where the fixture clamps the tab 2 and the first connection portion 31 includes the transition portion 33. The clamping position is not flat, which can easily lead to defects such as cold welding and blowout holes, affecting the overcurrent capacity between the tab 2 and the pole assembly 4, and is not conducive to the battery's overcurrent and safety performance.

[0047] When measuring dimensions a and h, you can use a common length measuring tool, such as a ruler or tape measure.

[0048] Specifically, when measuring a, the surface of the second connecting portion 32 facing away from the battery cell body 1 is used as a reference plane. A length measuring tool is used to measure the distance between the reference plane and the edge of the transition portion 33 where it connects to the first connecting portion 31 along the second direction Z. Multiple measurements are taken and the average value is calculated to obtain the dimension a (mm) of the transition portion 33. When the transition portion 33 is configured as a 90° arc, a is also the radius of the transition portion 33. In this embodiment, a is also the distance between the two edges of the transition portion 33 projected in the second direction Z.

[0049] When measuring h, the surface of the second connecting portion 32 facing away from the battery body 1 is used as the reference plane, and the distance between the reference plane and the edge of the first connecting mark 21 close to the pole assembly 4 is measured along the second direction Z using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the distance h mm between the edge of the second connecting portion 32 facing away from the battery body 1 and the first connecting mark 21.

[0050] To support the rationality of the above numerical range, this embodiment also conducts tests and verifications on batteries that meet the above numerical range.

[0051] Test content: Taking lithium iron phosphate system batteries as an example, batteries of the same model and batch were selected for testing. Except for a, which selected different specifications, the models and sizes of other battery cell structural parts were the same.

[0052] Test 1: Welding of the tab 2: Use the conventional laser welding equipment and welding process of the production line to weld the tab 2 to the adapter 3. When welding each battery cell component, control the welding parameter h separately. After welding is completed, visually inspect the welding area for defects such as cold solder joints and holes.

[0053] Test 2: High-rate battery charge and discharge test. The battery cell components after welding in Test 1 are assembled into shells, and the processes such as liquid injection and formation are completed to form a finished battery. The finished battery is then charged and discharged.

[0054] Test equipment: charge and discharge tester, constant temperature box, data acquisition and monitoring system, the test temperature is 25℃.

[0055] Cross-current charging: The battery is charged at a constant current of 4C until the battery voltage reaches the rated charging voltage.

[0056] Constant voltage charging: When the battery voltage reaches the rated charging voltage, it switches to constant voltage charging and stops charging when the charging current drops to 0.05C.

[0057] Discharge process: The battery is discharged at a constant current of 4C until the battery voltage drops to the rated discharge cut-off voltage.

[0058] During the test, the data acquisition system collects the temperature at the battery pole and records the highest temperature of each battery pole during the charging process.

[0059] The normal temperature range is 40℃-45℃. If it is greater than 45℃, it does not meet the design requirements, indicating that serious heat is generated in the current transmission path between the pole and the battery cell.

[0060] Please refer to Table 1 for the test parameters and index data of each group.

[0061] Table 1

[0062]

[0063] It can be seen that when the ha of Example 1-22 meets the above range, while ensuring the overcurrent capacity, the battery has good welding quality and will not have serious heat generation problems. There are no welding defects in the welding area of ​​the tab 2, and it passes the high-rate charge and discharge test.

[0064] Among them, in Examples 1-3 and Examples 17-22, although there are no welding defects in the welding area of ​​the tab 2, and the temperature at the pole is within the design requirements after high-rate charge and discharge tests, each of them has some process defects.

[0065] In comparative examples 1-4, there are welding defects in the welding area of ​​the tab 2, and the pole temperature is found to exceed the design range during the charge and discharge test, which proves that the welding quality defects will affect the overcurrent, thereby causing abnormal temperature on the overcurrent path.

[0066] In comparative examples 5-7, there are no welding defects in the welding area of ​​the tab 2, but due to the long overcurrent path, the temperature of the pole is higher than the design temperature during the battery charge and discharge test.

[0067] In the second direction Z, for a and h, the following conditions are satisfied: 6≤h≤14, 1≤a≤4.

[0068] Preferably, h can take values ​​such as 6, 8.1, 9.4, 10, 11.8, 13.6, and 14.

[0069] Preferably, a can take values ​​such as 1, 1.5, 2.7, 3.3, or 4.

[0070] When the value of h is small, there is equipment interference during the welding process. When the value of h is large, the area on the upper end of the tab 2 that is not welded and gathered is large, and there is a problem of bending and wrinkling of the tab 2.

[0071] When the value of a is small, the manufacturing process of the battery adapter 3 is more difficult. When the value of a is large, the transition portion 33 of the adapter 3 occupies a large space, affecting the overall energy density of the battery.

[0072] In some embodiments, please refer to Figure 3 and Figure 6 In the second direction Z, the edge of the first connecting portion 31 facing away from the second connecting portion 32 is flush with the edge of the battery cell body 1 facing away from the second connecting portion 32 .

[0073] In this structure, the adapter plate 3 extends from the top surface of the battery cell body 1 to the bottom surface of the battery cell body 1. The adapter plate 3 has a larger overall area, a larger heat dissipation area, and better heat dissipation performance.

[0074] In the second direction Z, a and h also satisfy: 6 ≤ h - a ≤ 14. Preferably, ha can take values ​​such as 6, 7.9, 9.1, 11, 12.4, 13.8, and 14.

[0075] When ha meets this range, it can meet the overcurrent requirements, control the heat generation in the overcurrent area, and improve the battery's charging and discharging performance and battery safety.

[0076] In some embodiments, please refer to Figure 7In the second direction Z, the size of the adapter 3 is d mm, the size of the battery cell body 1 is D mm, and the following conditions are satisfied: 1 / 3 ≤ d / D ≤ 2 / 3, 1 ≤ h - a ≤ 7. Preferably, ha can be 1, 2.1, 3.7, 5, 6.2, 7, etc.

[0077] When 1 / 3 ≤ d / D ≤ 2 / 3 is satisfied, the adapter plate 3 extends from the top surface of the battery cell body 1 to the middle of the battery cell body 1, simplifying the structure of the adapter plate 3, reducing the weight of the battery, and making it easier for the battery cell body 1 to enter the shell when the battery cell body 1 enters the shell.

[0078] When measuring d and D, you can use a common length measuring tool, such as a ruler or tape measure.

[0079] Specifically, when measuring d, the surface of the second connecting portion 32 facing away from the battery body 1 is used as the reference plane, and the distance between the reference plane and the edge of the first connecting portion 31 away from the second connecting portion 32 is measured along the second direction Z using a length measuring tool. The measurement is repeated multiple times and the average value is taken to obtain the size of the adapter 3 as d mm.

[0080] When measuring D, either the top or bottom surface of the cell body 1 is used as a reference plane, and the distance between the reference plane and the other plane is measured along the second direction Z using a length measuring tool. Multiple measurements are taken and the average value is taken to obtain the size of the cell body 1 as D mm.

[0081] Due to the simplified structure of the adapter plate 3, the heat dissipation area of ​​the adapter plate 3 and the reserved welding space are relatively small. When 1≤h - a ≤7 is satisfied, it can not only ensure the welding quality of the tab 2 and the first connecting portion 31 and meet the overcurrent requirements, but also control the heat generation in the overcurrent area, thereby improving the charging and discharging performance of the battery and the battery safety.

[0082] In some embodiments, please refer to Figure 8 and Figure 9 In the second direction Z, the two ends of the tab 2 are flush with the two ends of the cell body 1 .

[0083] For this full-tab 2 structure, the tab 2 does not need to be cut when forming the tab 2 .

[0084] Please refer to Figure 8 The adapter 3 extends from the top surface of the battery cell body 1 to the bottom of the battery cell body 1. The adapter 3 can better support the tab 2 to prevent the tab 2 from tearing and deformation. The adapter 3 also has a large heat dissipation area and can better dissipate heat. Please refer to Figure 9The adapter sheet 3 extends from the top surface of the battery cell body 1 to the middle of the battery cell body 1. The tab 2 near the bottom of the battery cell body 1 can be folded and fitted to the side of the battery cell body 1. The simplified adapter sheet 3 allows the battery cell body 1 to enter the shell more easily, preventing the tab 2 from being wrinkled and pulled apart when entering the shell.

[0085] In some embodiments, please refer to Figure 10 and Figure 11 In the second direction Z, the tab 2 is located on the center line of the battery cell body 1 , and at least one end of the tab 2 is spaced apart from the edge of the corresponding end of the battery cell body 1 .

[0086] In this embodiment, the center line of the tab 2 coincides with the center line of the cell body 1 .

[0087] For this non-full tab 2 structure, when forming the tab 2 , the tab 2 needs to be cut and shaped.

[0088] Please refer to Figure 10 The adapter plate 3 extends from the top surface of the battery cell body 1 to the bottom of the battery cell body 1. The adapter plate 3 has a large heat dissipation area and can dissipate heat better. Figure 11 The adapter plate 3 extends from the top surface of the battery cell body 1 to the middle of the battery cell body 1. The tab 2 near the bottom of the battery cell body 1 can be retracted and fitted to the side of the battery cell body 1. The simplified adapter plate 3 can reduce the weight of the battery and make it easier for the battery cell body 1 to enter the shell when the battery cell body 1 enters the shell.

[0089] In some embodiments, please refer to Figure 3 and Figure 4 The tab 2 has a second connection mark 22, and the first connection mark 21 is located inside at least one of the second connection marks 22. In the second direction Z, the distance between the edge of the second connection portion 32 facing away from the battery cell body 1 and the first connection mark 21 is L mm, satisfying the following: 6 ≤ L - a ≤ 13. Preferably, La can be 6, 7, 8.3, 10, 11.9, 12.5, 13, etc.

[0090] The second connection mark 22 is a weld mark formed by ultrasonic welding to gather the tabs 2, that is, multiple layers of tabs 2 are stacked together and ultrasonically welded together to form the second connection mark 22. The tabs 2 and the first connecting portion 31 are then welded together to form the first connection mark 21, avoiding gaps between the layers of tabs 2 that may cause a poor weld. At the same time, the first connection mark 21 is located inside the second connection mark 22, limiting the distance between the second connection mark 22 and the transition portion 33, preventing the first connection mark 21 from being too close to the transition portion 33, affecting the flow capacity between the tabs 2 and the terminal assembly 4, and being detrimental to the flow and safety performance of the battery.

[0091] When measuring dimension L, you can use a common length measuring tool, such as a ruler or tape measure.

[0092] Specifically, when measuring L, the surface of the second connection part 32 on the side facing away from the battery body 1 is used as the reference plane, and the distance between the reference plane and the edge of the second connection mark 22 close to the pole assembly 4 is measured along the second direction Z by a length measuring tool. The measurement is taken multiple times and the average value is taken to obtain the distance L mm between the edge of the second connection part 32 on the side facing away from the battery body 1 and the first connection mark 21.

[0093] In the second direction Z, two ends of the tab 2 are flush with two ends of the cell body 1 , and a plurality of second connection marks 22 are provided and arranged along the second direction Z.

[0094] Through such a structure, different positions of the tab 2 can be gathered and welded to prevent the tab 2 from being scattered and torn. This can not only ensure the welding quality of the tab 2 and the adapter 3, but also facilitate the insertion of the battery cell body 1 into the shell.

[0095] The distance between two adjacent second connection marks 22 is t mm, which satisfies: 10≤t≤40. t can be 10, 15, 21, 26, 31, 33, 39, 40, etc.

[0096] When the above range is met, the tabs 2 between two adjacent second connection marks 22 are not easily torn, thereby improving the yield rate of battery assembly manufacturing.

[0097] When measuring dimension t, you can use a common length measuring tool, such as a ruler or tape measure.

[0098] Specifically, when measuring t, the distance between two opposite edges of two adjacent second connecting marks 22 is measured, and the measurement is repeated multiple times and the average value is taken to obtain the distance t mm between the two adjacent second connecting marks 22 .

[0099] A first connection mark 21 is provided inside each second connection mark 22 .

[0100] For the full-tab 2 structure, in order to allow the adapter 3 to better support the tab 2, the adapter 3 extends from the top surface of the battery cell body 1 to the bottom of the battery cell body 1, and a first connection mark 21 is set inside each second connection mark 22, which can improve the strength of the tab 2 and better dissipate heat.

[0101] There is a distance between the edge of the first connection portion 31 away from the second connection portion 32 and the edge of the cell body 1 away from the second connection portion 32 . The first connection mark 21 is provided inside the second connection mark 22 opposite to the first connection portion 31 .

[0102] For the full-ear tab 2 structure, in order to facilitate the insertion of the battery cell body 1 into the shell, the adapter plate 3 extends from the top surface of the battery cell body 1 to the middle of the battery cell body 1, so that a part of the ear tab 2 is connected to the adapter plate 3 to form a first connection mark 21. In other words, the first connection mark 21 is not set inside a part of the second connection mark 22. These second connection marks 22 are close to the bottom of the battery cell body 1. While ensuring the welding strength of the ear tab 2 and the adapter plate 3 and the heat dissipation capacity of the adapter plate 3, it can prevent the ear tab 2 from dispersing and tearing, making it easier for the battery cell body 1 to enter the shell.

[0103] In some embodiments, in the third direction Y, the minimum distance between the second connection mark 22 and the edge of the battery cell body 1 is M mm, satisfying: 2≤ M ≤ 10. Preferably, M can be 2, 4.4, 5.9, 6.2, 7.7, 8, 9.4, 10, etc.

[0104] If the value of M is too small, the distance between the second connection mark 22 and the battery body 1 is too small, and the distance from the edge of the first connection part 31 is too small. There is a risk of welding the first connection mark 21 during welding. If the value of M is too large, the size of the second connection mark 22 itself is too small, which will affect the connection quality of the multi-layer tabs 2 stacked together.

[0105] When measuring dimension M, you can use a common length measuring tool, such as a ruler or tape measure.

[0106] Specifically, when measuring M, the side of the battery cell body 1 that is closer to the second connection mark 22 in the third direction Y is used as the reference plane, and the distance between the reference plane and the edge of the second connection mark 22 close to the reference plane is measured along the third direction Y by a length measuring tool. The measurement is performed multiple times and the average value is taken to obtain the minimum distance M mm between the second connection mark 22 and the edge of the battery cell body 1.

[0107] In some embodiments, please refer to Figure 4 and Figure 12 In the first direction X, at least a portion of the tab 2 and the cell body 1 are located on both sides of the first connecting portion 31 .

[0108] When the tab 2 and the adapter 3 are assembled, the tab 2 will be folded and a portion of it will be attached to the surface of the first connecting portion 31 of the adapter 3 facing away from the battery cell body 1, so as to avoid wrinkling and tearing of the tab 2 between the adapter 3 and the battery cell body 1. In addition, the welding position is located outside the first connecting portion 31, which can facilitate welding positioning.

[0109] In some embodiments, please refer to Figure 13 In the first direction X, the tab 2 is located between the first connecting portion 31 and the battery cell body 1 .

[0110] When the tab 2 and the adapter 3 are assembled, the tab 2 will be folded and a portion of it will be attached to the surface of the first connecting portion 31 of the adapter 3 facing the battery body 1. When the tab is inserted into the shell, the first connecting portion 31 protects the tab 2 and prevents the tab 2 from tearing.

[0111] In some embodiments, the battery cell body 1 is a laminated battery cell, and the battery cell body 1 includes pole pieces and diaphragms. The pole pieces are stacked layer by layer along the second direction Z, and the diaphragm is arranged between two adjacent pole pieces, and the two adjacent pole pieces are arranged separately.

[0112] The battery cell body 1 includes a separator and two electrodes of opposite polarity, namely a positive electrode and a negative electrode. The battery cell cycle process is the process of metal ions moving from the positive electrode to the negative electrode, and then from the negative electrode to the positive electrode.

[0113] The electrodes are stacked layer by layer, with electrodes of the same polarity being discontinuous. A separator is provided between the positive and negative electrodes to form a laminated battery cell. The electrode assembly also includes a tab 2, which is electrically connected to the electrode. The positive tab is electrically connected to the positive electrode, and the negative tab is electrically connected to the negative electrode. The battery cell body 1 is charged and discharged via the positive and negative tabs. The electrode includes a current collector and an active material layer, which is coated on the surface of the current collector. If the electrode is a positive electrode, the current collector can be made of aluminum, and the active material layer can be made of lithium cobalt oxide, lithium iron phosphate, ternary lithium, or lithium manganese oxide. If the electrode is a negative electrode, the current collector can be made of copper, and the active material layer can be made of carbon or silicon.

[0114] Compared with wound cells, stacked cells have higher internal space utilization and relatively lower risk of lithium plating in battery electrodes.

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A battery, characterized in that: include: Battery cell body; a tab, which is provided at at least one end of the battery cell body along the first direction; The adapter includes a first connecting portion and a second connecting portion, wherein the first connecting portion is located on one side of the battery cell body in the first direction, the first connecting portion is connected to the tab and forms a first connecting mark, and the second connecting portion is located on one side of the battery cell body in the second direction, the first connecting portion and the second connecting portion are connected to each other and form a transition portion at the connection; a pole assembly connected to the second connecting portion; In the second direction, the size of the transition portion is a mm, the distance between the plane where the edge of the second connecting portion faces away from the battery cell body and the first connecting mark is h mm, and 1≤h-a≤14 is satisfied.

2. The battery according to claim 1, wherein: In the second direction, the size of the transition portion is a mm, the distance between the edge of the second connection portion facing away from the battery cell body and the first connection mark is h mm, and the following conditions are satisfied: 6≤h≤14, 1≤a≤4.

3. The battery according to claim 1, wherein: In the second direction, the edge of the first connecting portion facing away from the second connecting portion is flush with the edge of the battery cell body facing away from the second connecting portion; In the second direction, a dimension a mm of the transition portion and a distance h mm between an edge of the second connection portion facing away from the battery cell body and the first connection mark further satisfy: 6≤h-a≤14.

4. The battery according to claim 1, wherein: In the second direction, the size of the adapter is d mm, the size of the battery cell body is D mm, and the following conditions are satisfied: 1 / 3≤ d / D ≤ 2 / 3, 1≤ h - a ≤7.

5. The battery according to any one of claims 1, 3 or 4, characterized in that: In the second direction, two ends of the tab are flush with two ends of the battery cell body.

6. The battery according to any one of claims 1, 3 or 4, characterized in that: In the second direction, the tab is located on the center line of the battery cell body, and at least one end of the tab is spaced apart from an edge of a corresponding end of the battery cell body.

7. The battery according to claim 1, wherein: The tab has a second connection mark, the first connection mark is located inside at least one of the second connection marks, and in the second direction, the distance between the edge of the second connection portion facing away from the battery body and the first connection mark is L mm, satisfying: 6≤ L - a ≤13.

8. The battery according to claim 7, characterized in that: In the second direction, two ends of the tab are flush with two ends of the cell body, and a plurality of second connection marks are provided and arranged along the second direction.

9. The battery according to claim 8, characterized in that: The distance between two adjacent second connecting marks is t mm, satisfying: 10≤ t ≤40.

10. The battery according to claim 8, characterized in that: The first connection mark is arranged inside each of the second connection marks.

11. The battery according to claim 7, wherein: There is a distance between an edge of the first connection portion facing away from the second connection portion and an edge of the cell body facing away from the second connection portion, and the first connection mark is provided inside the second connection mark opposite to the first connection portion.

12. The battery according to claim 7, wherein: In the third direction, the minimum distance between the second connection mark and the edge of the battery cell body is M mm, satisfying: 2≤ M ≤10; The third direction, the second direction and the first direction are perpendicular to each other.

13. The battery according to claim 5, characterized in that: In the first direction, at least a portion of the tab and the battery cell body are located on both sides of the first connecting portion.

14. The battery according to claim 6, wherein: In the first direction, at least a portion of the tab and the battery cell body are located on both sides of the first connecting portion.

15. The battery according to claim 5, characterized in that: In the first direction, the tab is located between the first connecting portion and the battery cell body.

16. The battery according to claim 6, characterized in that: In the first direction, the tab is located between the first connecting portion and the battery cell body.

17. The battery according to claim 1, wherein: The battery cell body is a laminated battery cell, and the battery cell body includes pole pieces and diaphragms. The pole pieces are stacked in layers along the second direction, and the diaphragm is arranged between two adjacent pole pieces, and the two adjacent pole pieces are arranged separately.

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