Pole piece structure and battery

Abstract

The utility model belongs to the technical field of battery manufacturing, and discloses a pole piece structure and a battery, the pole piece structure comprises a positive pole piece and a negative pole piece, the positive pole piece is provided with a positive pole clearance area, and a positive pole lug extends into the positive pole clearance area from the positive pole piece; the negative pole piece is provided with a negative pole clearance area, and the negative pole lug extends into the negative pole clearance area from the negative pole piece; and in the stacking direction of the positive plate and the negative plate, the projections of the positive pole clearance area and the negative pole clearance area coincide to form a pole plate clearance area, the projections of the positive pole lug and the negative pole lug fall into the pole plate clearance area, and the projection of the positive pole lug and the projection of the negative pole lug do not coincide. The positive pole piece and the negative pole piece are both special-shaped pole pieces, and the positive pole piece and the negative pole piece are stacked, so that the internal space of the battery is effectively utilized, and the energy density of the assembled battery is further improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to battery manufacturing technical field especially relates to a pole piece structure and battery. BACKGROUND

[0002] Lithium ion battery is widely used in digital products, electric tools and power toys and other fields because of its characteristics of large discharge current, good stability, good safety and large capacity. With the improvement of living standards, personalized digital products emerge in an endless stream, such as wristwatch, wrist pressure gauge and AR glasses.

[0003] Due to the wide application of the above-mentioned personalized electronic products in various aspects, special requirements are put forward for the shape of the battery, and the size of the battery gradually develops towards small size.

[0004] In the traditional battery structure, the positive and negative electrodes of the battery protrude on the same side and are welded on the top cover plate, and the positive and negative electrodes contain a liquid injection hole, which is sealed by a liquid injection steel nail or a liquid injection hole plug. When the size of the battery decreases, the size of the positive and negative electrode tabs also decreases, and at the same time, the size of the positive electrode column and the liquid injection steel nail also decreases. When the width of the battery cell decreases to the extent that it cannot simultaneously accommodate the positive and negative electrodes and the liquid injection hole, the general treatment method is to separate the positive and negative electrodes and weld them on the opposite sides. This design wastes a large amount of space inside the battery, resulting in a decrease in the energy density of the battery. SUMMARY

[0005] One object of the present utility model is to provide a pole piece structure which effectively utilizes the internal space of the battery by stacking the special-shaped pole pieces, thereby improving the energy density of the assembled battery.

[0006] To achieve this object, the utility model adopts the following technical solutions:

[0007] The pole piece structure comprises:

[0008] A positive pole piece, the positive pole piece is provided with a positive pole avoidance area, and a positive pole tab extends from the positive pole piece to the positive pole avoidance area;

[0009] A negative pole piece, the negative pole piece is provided with a negative pole avoidance area, and a negative pole tab extends from the negative pole piece to the negative pole avoidance area;

[0010] Along the stacking direction of the positive pole piece and the negative pole piece, the projections of the positive pole avoidance area and the negative pole avoidance area coincide to form a pole piece avoidance area, the projections of the positive pole tab and the negative pole tab all fall into the pole piece avoidance area, and the projection of the positive pole tab and the projection of the negative pole tab do not coincide.

[0011] Optionally, the positive electrode avoidance region is arranged at one end of the positive electrode sheet in the length direction, and the negative electrode avoidance region is arranged at one end of the negative electrode sheet in the length direction.

[0012] Optionally, when the positive electrode sheet and the negative electrode sheet are arranged in a stacked manner, the positive electrode tab and the negative electrode tab are perpendicular.

[0013] Optionally, the two sides of the positive electrode sheet are coated with a first active material layer; and / or, the two sides of the negative electrode sheet are coated with a second active material layer.

[0014] Another object of the utility model provides a kind of battery, including shell and above-mentioned pole piece structure, multiple the positive electrode sheet and multiple the negative electrode sheet are alternately stacked to form pole piece battery, the pole piece battery is arranged in the shell, liquid injection hole is set on the shell, along the stacking direction of the positive electrode sheet and the negative electrode sheet, the projection of the liquid injection hole falls in the pole piece avoidance region, and the projection of the liquid injection hole and the projection of the positive electrode tab and the negative electrode tab are not coincident.

[0015] Optionally, multiple the positive electrode tab is electrically connected to form positive electrode tab of battery, and multiple the negative electrode tab is electrically connected to form negative electrode tab of battery.

[0016] The battery further includes a positive pole, which is arranged through the side wall of the shell and is electrically connected with the positive electrode tab of the battery, the negative electrode tab of the battery is electrically connected with the shell, and the positive pole is insulated from the shell.

[0017] Optionally, the side wall of the shell is provided with a pole hole, a part of the positive pole is arranged through the pole hole and connected with the positive electrode tab of the battery, and another part of the positive pole is connected with an external electrical equipment.

[0018] Optionally, the shell includes a bottom shell and a top cover, the pole piece battery is arranged in the bottom shell, the top cover is connected with the top opening of the bottom shell in a snap-fit manner, and the liquid injection hole is arranged on the top cover.

[0019] Optionally, there is a gap between the positive electrode tab and the inner wall of the bottom shell, and there is a gap between the negative electrode tab and the inner wall of the bottom shell.

[0020] Optionally, the thickness of the positive electrode sheet located at both sides of the multiple positive electrode sheets is greater than the thickness of the remaining positive electrode sheets, and the thickness of the negative electrode sheet located at both sides of the multiple negative electrode sheets is greater than the thickness of the remaining negative electrode sheets.

[0021] The utility model has the advantages of:

[0022] The positive pole piece and the negative pole piece are different from the traditional rectangular pole piece in shape, and belong to special-shaped pole pieces.

[0023] The battery provided by the utility model includes a shell and the pole piece structure, multiple positive pole pieces and multiple negative pole pieces are alternately laminated to form a laminated pole core, and the laminated pole core is arranged in the shell, so that the space utilization rate in the battery shell is effectively improved, and the energy density of the battery is further improved. BRIEF DESCRIPTION OF DRAWINGS

[0024] In order to more clearly illustrate the technical scheme in the embodiments of the utility model, the drawings needed to be used in the description of the embodiments of the utility model will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the utility model, and other drawings can be obtained according to the contents of the embodiments of the utility model and the drawings by those skilled in the art without any creative labor.

[0025] Figure 1 is a structural schematic view of the positive pole piece provided by the utility model;

[0026] Figure 2 is a structural schematic view of the negative pole piece provided by the utility model;

[0027] Figure 3 is a partial projection structural schematic view of the positive pole piece and the negative pole piece along the laminated arrangement direction provided by the utility model;

[0028] Figure 4 is an exploded view of the battery provided by the utility model;

[0029] Figure 5 is Figure 4 is a local enlarged view of A in Fig. 6;

[0030] Figure 6is a structure schematic view of the laminated core and the bottom shell provided by the embodiment of the utility model;

[0031] Figure 7 is a axonometric view of the laminated core and the top cover provided by the embodiment of the utility model;

[0032] Figure 8 is a structure schematic view of the laminated core and the top cover provided by the embodiment of the utility model.

[0033] In the figure,

[0034] 1, positive pole piece; 11, positive pole blank area; 12, positive pole lug;

[0035] 2, negative pole piece; 21, negative pole blank area; 22, negative pole lug;

[0036] 100, laminated core;

[0037] 200, shell; 201, bottom shell; 2011, pole hole; 202, top cover; 2021, liquid injection hole; 203, sealing element. DETAILED DESCRIPTION

[0038] The technical scheme of the utility model will be further illustrated below by specific implementation manners and the accompanying drawings.

[0039] In order to make the purpose, technical scheme and advantage of the embodiment of the utility model more clear, the technical scheme in the embodiment of the utility model will be clearly and completely described below by combining the drawings in the embodiment of the utility model, obviously, the described embodiment is a part of the embodiment of the utility model, rather than all the embodiment. The components of the embodiment of the utility model described and shown in the accompanying drawings can be arranged and designed in various different configurations.

[0040] Therefore, the following detailed description of the embodiment of the utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but only represents selected embodiments of the utility model. Based on the embodiment in the utility model, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the utility model.

[0041] It should be noted that: similar signs and letters represent similar items in the following drawings, therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0042] In the description of the utility model, it needs to explain, the term "upper", "lower", "left", "right", "vertical", "horizontal", "internal", "external" and so on indicate the orientation or position relation is based on the orientation or position relation shown in the drawing, or it is the orientation or position relation of the utility model product when using commonly, only for the convenience of describing the utility model and simplifying the description, and cannot indicate or imply that the device or element must have a particular orientation, construct and operate, therefore cannot be understood as the limitation of the utility model.

[0043] In the description of the utility model, it also needs to explain, unless otherwise specified and limited, the term "set", "connect" should be broad sense, for example, can be fixed connection, can also be detachable connection, or integrally connected, can be mechanical connection, can also be electrical connection.

[0044] In the utility model, unless otherwise specified and limited, the first feature is "on" or "under" the second feature can include the first and second features directly contact, can also include the first and second features are not directly contact but contact through another feature between them.

[0045] In the description of the utility model, the term "and / or" is only a kind of description associated object associated relation, it can exist three kinds of relations, for example, A and / or B, can represent: exist A alone, simultaneously exist A and B, exist B alone these three cases.In addition, the character " / " in the utility model, generally indicates that the front and rear associated objects are a kind of "or" relation.

[0046] The embodiments of the utility model are described in detail below, the examples of the embodiments are shown in the drawings, wherein the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout the drawings.The embodiments described below by referring to the drawings are exemplary, only for explaining the utility model, and cannot be understood as the limitation of the utility model.

[0047] The embodiment provides a pole piece structure, such as Figures 1-3As shown, the pole piece structure includes a positive pole piece 1 and a negative pole piece 2. Among them, the positive pole piece 1 is provided with a positive pole avoidance area 11, and a positive pole lug 12 extends from the positive pole piece 1 into the positive pole avoidance area 11; the negative pole piece 2 is provided with a negative pole avoidance area 21, and a negative pole lug 22 extends from the negative pole piece 2 into the negative pole avoidance area 21. That is, the shapes of the positive pole piece 1 and the negative pole piece 2 are different from the traditional rectangular pole piece, and belong to the special-shaped pole piece structure.

[0048] When the positive pole piece 1 and the negative pole piece 2 are stacked, the projections of the positive pole avoidance area 11 and the negative pole avoidance area 21 coincide to form a pole piece avoidance area along the stacking direction of the positive pole piece 1 and the negative pole piece 2, and the projections of the positive pole lug 12 and the negative pole lug 22 all fall into the pole piece avoidance area. By such arrangement, it can be ensured that the positive pole lug 12 and the negative pole lug 22 do not exceed the stacking area of the positive pole piece 1 and the negative pole piece 2, and compared with the traditional design scheme in which the pole lug protrudes from the pole piece, the utilization rate of space can be effectively improved, thereby improving the energy density of the assembled battery. At the same time, the projection of the positive pole lug 12 and the projection of the negative pole lug 22 do not coincide, so as to avoid interference between the positive pole lug 12 and the negative pole lug 22, and ensure the use safety of the stacked pole piece 100 formed after the positive pole piece 1 and the negative pole piece 2 are stacked.

[0049] In this embodiment, as shown in the drawings, Figure 1 The positive pole piece 1 is rectangular, and the width of the rectangle is small and the length is large. A rectangular notch is arranged at the top corner of one end of the positive pole piece 1 in the length direction, which is the positive pole avoidance area 11. The side of the positive pole piece 1 corresponding to the positive pole avoidance area 11 extends into the positive pole avoidance area 11 to form a positive pole lug 12, and the positive pole lug 12 is parallel to the length direction of the positive pole piece 1. Correspondingly, the shape of the negative pole piece 2 is the same as that of the positive pole piece 1, and the difference is that a rectangular notch is arranged at the top corner of one end of the negative pole piece 2 in the length direction, which is the negative pole avoidance area 21. The side of the negative pole piece 2 corresponding to the negative pole avoidance area 21 extends into the negative pole avoidance area 21 to form a negative pole lug 22, and the negative pole lug 22 is parallel to the width direction of the negative pole piece 2.

[0050] That is, when the positive pole piece 1 and the negative pole piece 2 are stacked, the positive pole lug 12 of the positive pole piece 1 and the negative pole lug 22 of the negative pole piece 2 are in a perpendicular relationship. By such arrangement, when a plurality of positive pole pieces 1 and a plurality of negative pole pieces 2 are alternately stacked to form a stacked pole piece 100, the conductive connection between the plurality of positive pole lugs 12 and the conductive connection between the plurality of negative pole lugs 22 do not affect each other, and are not easy to interfere, thereby better ensuring the safety performance of the stacked pole piece 100.

[0051] Of course, in other embodiments, the extending directions of the positive tab 12 and the negative tab 22 can be interchanged, i.e., the positive tab 12 is parallel to the width direction of the positive plate 1, and the negative tab 22 is parallel to the width direction of the negative plate 2. Alternatively, in other embodiments, the positive tab 12 and the negative tab 22 are at an angle when the positive plate 1 and the negative plate 2 are stacked. As long as the projections of the positive tab 12 and the negative tab 22 do not overlap along the stacking direction of the positive plate 1 and the negative plate 2, interference between the positive tab 12 and the negative tab 22 can be avoided, and the specific extending directions of the positive tab 12 and the negative tab 22 can be designed according to actual conditions, which are not limited here.

[0052] Preferably, each end point of the positive plate 1 and the negative plate 2 is chamfered to cut the edges and corners of the positive plate 1 and the negative plate 2 to make them smooth. The chamfering can remove burrs on the edges, improve the appearance, and also help to reduce stress concentration and improve durability. The chamfering includes at least one of an inner concave fillet, an outer convex fillet, and a bevel C corner.

[0053] Optionally, in the present embodiment, the positive plate 1 and the negative plate 2 are both made of metal foil. Specifically, the positive plate 1 includes an aluminum foil layer, and the negative plate 2 includes a copper foil layer. Both aluminum foil and copper foil have excellent electrical conductivity and chemical stability, which enables them to effectively conduct current and withstand the high current density of the battery. The specific gravity of aluminum foil is small, and it has a high specific surface area, which can increase the loading capacity of active materials and thus improve the energy density of the battery. In addition, both aluminum foil and copper foil are relatively stable in air, and a dense oxide film can be formed on the surface of the aluminum foil to protect the internal aluminum, while the copper foil maintains the stability of its structure and electrochemical properties. In terms of mechanical strength, copper foil has high mechanical strength and can maintain the structural stability of the battery plate. Finally, from the cost point of view, copper and aluminum are common metal materials, and their prices are relatively low and resources are abundant.

[0054] Preferably, the aluminum foil layer and the copper foil layer in the present embodiment can both be made of carbon-coated foil, i.e., carbon-coated copper foil and aluminum foil. The thickness of the carbon coating ranges from 5 to 20 μm, such as 5 μm, 10 μm, 15 μm, and 20 μm, etc. If the carbon-coated foil is continuously coated, the distance between the side edge and the two sides of the foil ranges from 5 to 15 μm; if the foil is coated with carbon-coated foil at intervals, the two sides are fully coated, and the interval distance is 5 to 15 μm.

[0055] Furthermore, a first active material layer is coated on both sides of the positive electrode 1; and / or, a second active material layer is coated on both sides of the negative electrode 2. That is, a certain amount of active material can also be coated on both sides of the aluminum foil layer of the positive electrode 1 and / or on both sides of the copper foil layer of the negative electrode 2 to form a first active material layer or a second active material layer, thereby improving the peel strength between the active material and the foil. Exemplarily, the first and second active material layers may include one or a combination of several of the following: lithium cobalt oxide (LiCoO2), lithium manganese oxide, lithium iron phosphate (LiFePO4), lithium nickel oxide (LiNiO2), and lithium nickel cobalt manganese oxide (NCM). The selection and combination of these active materials depend on the specific application requirements of the battery, such as energy density, cycle life, safety, and cost, and are not limited in this embodiment.

[0056] It should be noted that peel strength refers to the force required to peel the active material layer from the foil, and it is used to measure the tightness of the bond between the active material and the foil. Within a certain range, a higher peel strength is better. However, most current anode formulations are water-based, using water as a solvent. This results in a relatively low bond between the active material and the foil on the electrode. Using a primer coating on the foil can significantly improve the bond between the two.

[0057] Furthermore, in this embodiment, both the positive electrode 1 and the negative electrode 2 require laser etching. Laser etching is performed on the coated thinning area to clean the first and second active material layers, respectively. Positive electrode tabs 12 and negative electrode tabs 22 are then die-cut in this area, thereby reducing the misalignment between the two sides of the positive electrode 1 and the negative electrode 2. It is understood that during lithium battery coating, active material is applied to both sides of the foil, but the two sides are not perfectly aligned. Laser etching re-establishes the empty foil area, which helps reduce the degree of misalignment.

[0058] Furthermore, due to the different coating methods and die-cutting directions of the electrodes, the areas requiring blank foil for die-cutting of the electrode tabs also differ. If the carbon-coated foil is continuously coated, the distance between its side edge and the two sides of the foil ranges from 5 to 15 μm; if the carbon-coated foil is intermittently coated, then both sides are fully coated, with a gap distance of 5 to 15 μm.

[0059] like Figures 4-8 As shown, this embodiment also provides a battery, including a housing 200 and an electrode structure provided in this embodiment.

[0060] Specifically, the plurality of positive electrode sheets 1 and the plurality of negative electrode sheets 2 are alternately stacked to form the jelly-roll 100, the jelly-roll 100 is arranged in the shell 200, and the shell 200 is provided with a liquid injection hole 2021. In the stacking direction of the positive electrode sheets 1 and the negative electrode sheets 2, the projection of the liquid injection hole 2021 falls within the electrode sheet avoidance area, and the projection of the liquid injection hole 2021 does not coincide with the projection of the positive electrode tab 12 and the projection of the negative electrode tab 22. That is, in the stacking direction of the positive electrode sheets 1 and the negative electrode sheets 2, the liquid injection hole 2021, the positive electrode tab 12, and the negative electrode tab 22 are all concentrated in the electrode sheet avoidance area (see Figure 8 ), the structure is compact, the internal space of the battery is effectively utilized, and the energy density of the battery is improved. At the same time, the three are not connected to each other and will not interfere with each other, and after the battery is assembled, it is convenient to inject electrolyte into the internal space of the battery through the liquid injection hole 2021.

[0061] Optionally, the battery further comprises a sealing member 203 for plugging the liquid injection hole 2021. The sealing member 203 can be selected according to actual needs, such as a liquid injection steel nail or a liquid injection hole plug in the prior art.

[0062] It can be understood that after the plurality of positive electrode sheets 1 and the plurality of negative electrode sheets 2 are alternately stacked to form the jelly-roll 100, the plurality of positive electrode tabs 12 need to be electrically connected to form the positive electrode tab of the battery, and the plurality of negative electrode tabs 22 need to be electrically connected to form the negative electrode tab of the battery. In this embodiment, the connection mode between the plurality of positive electrode tabs 12 and the connection mode between the plurality of negative electrode tabs 22 are both ultrasonic welding. The specific mode of connection is not limited to ultrasonic welding, and in other embodiments, other welding modes can also be used as long as the electrical connection between the positive electrode tabs 12 and the electrical connection between the negative electrode tabs 22 can be achieved.

[0063] Continuing to refer to Figure 4 and Figure 5 , the shell 200 comprises a bottom shell 201 and a top cover 202. The jelly-roll 100 is arranged in the bottom shell 201, and the top cover 202 is connected to the top opening of the bottom shell 201 to seal the jelly-roll 100 in the accommodation space between the top cover 202 and the bottom shell 201. The liquid injection hole 2021 is provided on the top cover 202 to facilitate the injection of electrolyte into the accommodation space of the battery through the liquid injection hole 2021.

[0064] Specifically, the battery further comprises a positive electrode post (not shown in the figure). The sidewall of the bottom shell 201 is provided with a post hole 2011, a part of the positive electrode post penetrates the post hole 2011 and is electrically connected with the positive electrode tab of the battery, and the other part of the positive electrode post is connected with an external electrical equipment to realize the transmission of electric energy. The position of the post hole 2011 needs to be flexibly selected according to the arrangement position of the positive electrode tab 12 to facilitate the welding connection between the positive electrode tab 12 and the positive electrode post to be optimal.

[0065] More specifically, the negative electrode tab of the battery cell is electrically connected to the bottom shell 201, and the bottom shell 201 of the battery serves as the negative electrode connection terminal (i.e., the negative terminal post). The bottom shell 201 is made of metal material to facilitate conductivity.

[0066] More specifically, to prevent a short circuit between the positive terminal and the bottom shell 201, the positive terminal and the shell 200 are insulated. In this embodiment, an insulating ring can be added between the positive terminal and the bottom shell 201 to achieve insulation. The insulating ring is made of materials such as plastic; or other insulation methods can be used, which are not limited here.

[0067] Preferably, such as Figure 4 and Figure 6 As shown, in this embodiment, there is a gap between the positive electrode tab 12 and the inner wall of the bottom shell 201 to avoid contact between the positive electrode tab 12 and the inner wall of the bottom shell 201, which could cause a short circuit. Specifically, the distance between the positive electrode tab 12 and the inner wall of the bottom shell 201 is 0-20mm, preferably greater than 0mm and not exceeding 20mm, such as 5mm, 10mm, 15mm and 20mm.

[0068] Similarly, there is a gap between the negative electrode tab 22 and the inner wall of the bottom shell 201 to avoid the liquid injection hole 2021 and facilitate liquid injection. Specifically, the distance between the negative electrode tab 22 and the inner wall of the bottom shell 201 is 0-20mm, preferably greater than 0mm and not exceeding 20mm, such as 5mm, 10mm, 15mm and 20mm.

[0069] Preferably, in this embodiment, the thickness of the positive electrode 1 located on both sides of the plurality of positive electrode sheets 1 is greater than the thickness of the remaining positive electrode sheets 1, and the thickness of the negative electrode 2 located on both sides of the plurality of negative electrode sheets 2 is greater than the thickness of the remaining negative electrode sheets 2. It is understood that when the width of the electrode tabs is very narrow, ultrasonic welding can easily lead to breakage of the electrode tabs on both sides. Increasing the thickness of the electrode foil on both sides increases the strength, making it less prone to breakage during welding. At the same time, the strength and ductility of the positive electrode sheets 1 and negative electrode sheets 2 located on both sides are superior to those of the middle layers of positive electrode sheets 1 and negative electrode sheets 2.

[0070] Specifically, in this embodiment, the thickness of the positive electrode 1 located on both sides is 16-25 μm, and the thickness of the negative electrode 2 located on both sides is 12-30 μm. The thickness of the remaining positive electrode 1 is 6-12 μm, and the thickness of the remaining negative electrode 2 is 4-12 μm.

[0071] Obviously, the above embodiments of the present application are merely examples for clearly illustrating the present application, and are not intended to limit the implementation modes of the present application. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and also impossible to exhaust all the implementation modes. Any modification, equivalent replacement and improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application claims.

Claims

1. A pole piece structure characterized by, The application relates to a battery, which comprises: a positive electrode sheet (1) provided with a positive electrode blank area (11), wherein a positive electrode tab (12) extends from the positive electrode sheet (1) into the positive electrode blank area (11); a negative electrode sheet (2) provided with a negative electrode blank area (21), wherein a negative electrode tab (22) extends from the negative electrode sheet (2) into the negative electrode blank area (21); the projections of the positive electrode blank area (11) and the negative electrode blank area (21) coincide to form an electrode sheet blank area in the stacking direction of the positive electrode sheet (1) and the negative electrode sheet (2), the projections of the positive electrode tab (12) and the negative electrode tab (22) all fall into the electrode sheet blank area, and the projection of the positive electrode tab (12) and the projection of the negative electrode tab (22) do not coincide.

2. The pole piece structure of claim 1, wherein The positive electrode blank area (11) is arranged at one end of the positive electrode sheet (1) in the length direction, and the negative electrode blank area (21) is arranged at one end of the negative electrode sheet (2) in the length direction.

3. The pole piece structure of claim 1, wherein When the positive electrode sheet (1) and the negative electrode sheet (2) are arranged in a stack, the positive electrode tab (12) is perpendicular to the negative electrode tab (22).

4. The pole piece structure of claim 1, wherein The two sides of the positive electrode sheet (1) are coated with a first active material layer, and / or the two sides of the negative electrode sheet (2) are coated with a second active material layer.

5. A battery characterized by The application further relates to a battery, which comprises a shell (200) and the electrode sheet structure as claimed in any one of claims 1-4, a plurality of the positive electrode sheets (1) and a plurality of the negative electrode sheets (2) are alternately arranged in a stack to form a stacked electrode core (100), the stacked electrode core (100) is arranged in the shell (200), a liquid injection hole (2021) is arranged on the shell (200), the projection of the liquid injection hole (2021) falls into the electrode sheet blank area in the stacking direction of the positive electrode sheet (1) and the negative electrode sheet (2), and the projection of the liquid injection hole (2021) does not coincide with the projection of the positive electrode tab (12) and the projection of the negative electrode tab (22).

6. The battery of claim 5, wherein, A plurality of the positive electrode tabs (12) are electrically connected to form a positive electrode tab of the battery, and a plurality of the negative electrode tabs (22) are electrically connected to form a negative electrode tab of the battery. The battery further comprises a positive electrode column, the positive electrode column penetrates the side wall of the shell (200) and is electrically connected with the positive electrode tab of the battery, the negative electrode tab of the battery is electrically connected with the shell (200), and the positive electrode column is insulated from the shell (200).

7. The battery of claim 6, wherein, A pole hole (2011) is arranged on the side wall of the shell (200), a part of the positive electrode column penetrates the pole hole (2011) and is connected with the positive electrode tab of the battery, and another part of the positive electrode column is connected with an external electric device.

8. The battery according to any one of claims 5-7, characterized in that, The shell (200) comprises a bottom shell (201) and a top cover (202), the stacked electrode core (100) is arranged in the bottom shell (201), the top cover (202) is connected to the top opening of the bottom shell (201) in a buckling mode, and the liquid injection hole (2021) is arranged on the top cover (202).

9. The battery of claim 8, wherein, There is a gap between the positive electrode tab (12) and the inner wall of the bottom shell (201), and there is a gap between the negative electrode tab (22) and the inner wall of the bottom shell (201).

10. The battery of any one of claims 5-7, wherein, The thickness of the positive electrode sheet (1) on both sides of the plurality of positive electrode sheets (1) is greater than the thickness of the remaining positive electrode sheets (1), and the thickness of the negative electrode sheet (2) on both sides of the plurality of negative electrode sheets (2) is greater than the thickness of the remaining negative electrode sheets (2).

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