Battery pole core, battery cell, battery and vehicle

Abstract

The utility model relates to a battery pole core, a battery cell, a battery and a vehicle, the battery pole core comprises multiple layers of positive plates and multiple layers of negative plates, the multiple layers of positive plates and the multiple layers of negative plates are alternately arranged, at least one of the positive plates and the negative plates forms an empty foil area on the surface opposite to the other one, and the empty foil area is used as an exhaust passage of the battery pole core. When high-temperature and high-pressure gas is generated due to thermal failure in the battery pole core, the high-temperature and high-pressure gas can be exhausted through a nearby exhaust channel (namely an empty foil area), so that the exhaust path is shortened, the exhaust rate is improved, the safety of the battery pole core is ensured, and large-scale thermal runaway caused by untimely heat extraction of the battery is avoided. And the hollow foil area can also quickly discharge conventional heat generated in the pole core when the pole core works normally, so that the heat dissipation performance of the pole core is improved. The empty foil area is formed on the pole piece, an auxiliary structure does not need to be additionally arranged to serve as an exhaust channel, the space utilization rate is high, and the energy density of the battery pole core is improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of batteries, and in particular to a battery pole core, a battery cell, a battery and a vehicle. BACKGROUND

[0002] When the battery cell is in thermal runaway, a violent chemical reaction occurs inside the battery cell, accompanied by the generation of a large amount of heat and gas. In order to quickly exhaust the large amount of gas generated during thermal runaway, in the related art, an exhaust passage is mainly designed at the battery cell shell. However, such a design is not conducive to the high-temperature and high-pressure gas generated at the thermal runaway point far from the explosion-proof valve in the pole core. The high-temperature and high-pressure gas needs to pass through a long exhaust path to reach the exhaust passage and then be exhausted from the explosion-proof valve. As a result, the pressure in the battery cell is likely to be too high and the thermal runaway is likely to be large. SUMMARY

[0003] To overcome the problems in the related art, the present disclosure provides a battery pole core, a battery cell, a battery and a vehicle.

[0004] According to a first aspect of an embodiment of the present disclosure, a battery pole core is provided, comprising a plurality of positive electrode sheets and a plurality of negative electrode sheets, the plurality of positive electrode sheets and the plurality of negative electrode sheets are arranged alternately,

[0005] In the present disclosure, at least one of the positive electrode sheets and the negative electrode sheets forms an empty foil region on the surface opposite to the other, and the empty foil region is used as an exhaust passage of the battery pole core.

[0006] Optionally, at least one of the positive electrode sheets and the negative electrode sheets comprises an intermittently coated coating region, so as to form the empty foil region between two adjacent coating regions.

[0007] Optionally, in the arrangement direction of the positive electrode sheets and the negative electrode sheets, the projection of the empty foil region is a first rectangle, the length of the first rectangle is d, and the width of the first rectangle is equal to the width of the corresponding positive electrode sheet or negative electrode sheet, wherein 1mm≤d≤10mm.

[0008] Optionally, one layer of the positive electrode sheet and one layer of the negative electrode sheet adjacent to each other form a layer group, and the number of the layer groups is a plurality and each layer group is provided with the empty foil region.

[0009] Optionally, in each layer group, the number of the empty foil regions is a plurality.

[0010] Optionally, one of the positive electrode sheets and the negative electrode sheets forms the empty foil region, and the position of the surface of the other corresponding to the empty foil region is provided with a protective layer for preventing metal deposition.

[0011] Optionally, the protective layer is a corrosion-resistant adhesive tape attached to the positive electrode sheet or the negative electrode sheet.

[0012] Optionally, in the arrangement direction of the positive electrode sheet and the negative electrode sheet, a projection of the protection layer covers a projection of the empty foil region.

[0013] Optionally, in the arrangement direction of the positive electrode sheet and the negative electrode sheet, a projection of the empty foil region is a first rectangle, and a projection of the protection layer is a second rectangle, the second rectangle has a length a and a width b, and the first rectangle has a length d and a width c, wherein b-c≥0.1mm and a-d≥1mm.

[0014] Optionally, the empty foil region is formed in the negative electrode sheet.

[0015] According to a second aspect of the embodiments of the present disclosure, an electric core is provided, comprising the battery pole core described above.

[0016] According to a third aspect of the embodiments of the present disclosure, a battery is provided, comprising the electric core described above.

[0017] According to a fourth aspect of the embodiments of the present disclosure, a vehicle is provided, comprising the battery described above.

[0018] The technical solutions provided by the embodiments of the present disclosure can have the following beneficial effects: when high-temperature and high-pressure gas is generated due to thermal failure inside the battery pole core, the high-temperature and high-pressure gas can be discharged through the nearby exhaust passage (i.e. the empty foil region), which shortens the exhaust path and improves the exhaust rate, ensures the safety of the battery pole core, and avoids large-scale thermal runaway due to the untimely heat dissipation of the battery. In addition, by setting the empty foil region, the conventional heat generated inside the pole core can also be quickly discharged when the pole core is working normally, thereby improving the heat dissipation performance of the pole core. Furthermore, the empty foil region is formed on at least one of the positive electrode sheet and the negative electrode sheet, without the need for additional auxiliary structures to serve as the exhaust passage, which has high space utilization and is conducive to improving the energy density of the battery pole core.

[0019] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0020] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0021] Figure 1 is a top view of a battery pole core according to an example of the present disclosure;

[0022] Figure 2 is a front view of a positive electrode sheet and a negative electrode sheet according to an example of the present disclosure.

[0023] LEGEND OF THE DRAWINGS

[0024] 1 - positive electrode sheet; 2 - negative electrode sheet; 31 - empty foil area; 32 - coated area; 41 - first rectangle; 42 - second rectangle; 5 - protective layer; 6 - separator. DETAILED DESCRIPTION

[0025] The exemplary embodiments will be described in detail herein with reference to the accompanying drawings. In the following description, unless otherwise indicated, like numbers in the different drawings represent similar or identical elements. The following exemplary embodiments described are not meant to represent all embodiments consistent with the present disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0026] Referring to Figures 1-2 The present disclosure exemplarily shows a battery electrode core, which comprises a plurality of positive electrode sheets 1 and a plurality of negative electrode sheets 2, and the plurality of positive electrode sheets 1 and the plurality of negative electrode sheets 2 are arranged alternately, i.e. the arrangement mode is one positive electrode sheet 1, one negative electrode sheet 2, one positive electrode sheet 1, one negative electrode sheet 2, and so on. At least one of the positive electrode sheet 1 and the negative electrode sheet 2 forms an empty foil area 31 on the surface opposite to the other, and the empty foil area 31 is used as an exhaust passage of the battery electrode core. That is, the present disclosure does not limit the position of the empty foil area 31, which can be formed on the positive electrode sheet 1, or on the negative electrode sheet 2, or on both the positive electrode sheet 1 and the negative electrode sheet 2. Since the positive electrode sheet 1 and the negative electrode sheet 2 are both multi-layered, the empty foil area 31 can be formed on any one or more layers of the electrode sheets (positive electrode sheet 1 or negative electrode sheet 2), which is not limited by the present disclosure.

[0027] It needs to be explained that the positive electrode sheet 1 and the negative electrode sheet 2 of the battery electrode core are both metal foils (e.g. copper sheet, aluminum sheet) coated with active material on the surface, and the "empty foil area 31" here refers to the area on the metal foil body without coating of active material.

[0028] Referring to Figure 1 In the embodiments of the present disclosure, a separator 6 can be arranged between the positive electrode sheet 1 and the negative electrode sheet 2, which separates the positive electrode sheet 1 and the negative electrode sheet 2, and ensures that the electrons can only flow between the positive electrode sheet 1 and the negative electrode sheet 2 through the external circuit, but cannot be directly conducted within the electrode core. For example, in the charging and discharging process of a lithium ion battery, lithium ions can shuttle between the positive electrode sheet 1 and the negative electrode sheet 2 through the pores of the separator 6, while electrons need to bypass the separator and flow from the negative electrode sheet 2 to the positive electrode sheet 1 through the external circuit, so as to realize the mutual conversion of electrical energy and chemical energy.

[0029] The present disclosure does not limit the forming mode of the plurality of positive electrode sheets 1 and the plurality of negative electrode sheets 2, for example, in the embodiments of the present disclosure, the positive electrode sheet 1 and the negative electrode sheet 2 can be formed by stacking a plurality of metal foils, and the metal foils can be connected by welding, or the metal foils can be connected by crimping, or the metal foils can be connected by other methods. Figure 1In the illustrated embodiment, one positive electrode sheet 1, one separator 6, and one negative electrode sheet 2 can be stacked, and then the three can be formed into multiple layers by winding. In addition, in other embodiments, the multiple positive electrode sheets 1 and the multiple negative electrode sheets 2 can also be formed into multiple layers by stacking, that is, multiple positive electrode sheets 1, multiple separators 6, and multiple negative electrode sheets 2 are alternately stacked in this order, and then the multiple positive electrode sheets 1 are sequentially electrically connected, and the multiple negative electrode sheets 2 are sequentially electrically connected, so as to form the multiple positive electrode sheets 1 and the multiple negative electrode sheets 2.

[0030] By the above technical solution, when high-temperature and high-pressure gas is generated due to thermal failure inside the battery pole core, the high-temperature and high-pressure gas can be discharged through the nearby exhaust channel (i.e., the empty foil area 31), shortening the exhaust path and improving the exhaust rate, ensuring the safety of the battery pole core, and avoiding large-scale thermal runaway due to the untimely heat dissipation of the battery. In addition, by providing the empty foil area 31, the conventional heat generated inside the pole core during normal operation can also be quickly discharged, improving the heat dissipation performance of the pole core. In addition, the empty foil area 31 is formed on at least one of the positive electrode sheet 1 and the negative electrode sheet 2, without the need for additional auxiliary structures to serve as an exhaust channel, and the space utilization rate is high, which is conducive to improving the energy density of the battery pole core.

[0031] As described above, the present disclosure does not limit how the empty foil area 31 is formed. For example, in embodiments of the present disclosure, at least one of the positive electrode sheet 1 and the negative electrode sheet 2 can include intermittently coated coating areas 32 to form the empty foil area 31 between two adjacent coating areas 32. Here, the coating area 32 refers to the active material coated on the metal foil. In addition, in other embodiments, the empty foil area 31 can also be obtained by removing the active material of the coating area 32.

[0032] Referring to Figure 2 In embodiments of the present disclosure, in the arrangement direction of the positive electrode sheet 1 and the negative electrode sheet 2, the projection of the empty foil area 31 can be a first rectangle 41, the length of the first rectangle 41 is d, and the width of the first rectangle 41 can be equal to the width of the corresponding positive electrode sheet 1 or negative electrode sheet 2, where 1 mm≤d≤10 mm, such as 1 mm, 5 mm, 10 mm, etc. Here, the “corresponding positive electrode sheet 1 or negative electrode sheet 2” refers to the positive electrode sheet 1 or negative electrode sheet 2 that forms the empty foil area 31. The length and width can be determined according to the actual situation Figure 2The length of the first rectangle 41 is d, and the width of the first rectangle 41 is the extension direction of the pole piece. The length d of the first rectangle 41 is set to 1 mm≤d≤10 mm. On the one hand, this can ensure the exhaust efficiency of the exhaust channel (if d is too small, the exhaust efficiency will be affected), and on the other hand, this can ensure the energy density of the battery pole core (if d is too large, the energy density will be affected). In addition, in other embodiments, the length d of the first rectangle 41 can also be set to 3 mm≤d≤8 mm. The specific size can be adaptively designed according to actual needs.

[0033] In order to improve the exhaust efficiency of the battery pole core, in the embodiments of the present disclosure, one layer of positive pole pieces 1 and one layer of negative pole pieces 2 adjacent to each other can constitute a layer group, and the number of layer groups can be multiple and each layer group is provided with an empty foil area 31. The empty foil area 31 is uniformly distributed in each position of the battery pole core, so that when thermal failure occurs at any position of the battery pole core, the exhaust channel in the same layer group can correspond to the position, and the heat can be discharged in time.

[0034] Referring to Figure 1 and Figure 2 In other embodiments, the number of empty foil areas 31 in each layer group can be multiple. In this way, the exhaust capacity of each layer group can be increased, and when thermal failure occurs at any position of the battery pole core, there can be an exhaust channel adjacent to the position.

[0035] Referring to Figure 1 and Figure 2 In the embodiments of the present disclosure, one of the positive pole pieces 1 and the negative pole pieces 2 can form the empty foil area 31, and the position of the surface of the other pole piece corresponding to the empty foil area 31 can be provided with a protective layer 5 for preventing metal deposition. The protective layer 5 can avoid the phenomenon that metal ions on the pole piece corresponding to the protective layer 5 move to the empty foil area 31 and form metal deposition in the empty foil area 31. The “metal deposition” here can be lithium deposition, sodium deposition, potassium deposition, etc., which is determined by the type of battery.

[0036] The present disclosure does not limit the protective layer 5, for example, in an embodiment of the present disclosure, the protective layer 5 can be a corrosion-resistant tape attached to the positive plate 1 or the negative plate 2. The corrosion-resistant tape can form a physical isolation layer between the positive plate 1 and the negative plate 2, thereby preventing metal ion migration and deposition. The "corrosion-resistant tape" mainly refers to the tape commonly used in battery cells that can resist corrosion of electrolyte. It can be attached to only one side of the positive plate 1 or the negative plate 2, or it can be wrapped around the positive plate 1 or the negative plate 2 once, so that it can prevent metal deposition on both sides of the empty foil area 31, thereby reducing the process difficulty and eliminating the need for two protective layer 5 arrangements for the empty foil area 31 on both sides. Of course, in this case, the positions of the empty foil areas 31 of the adjacent two layer groups need to correspond. In addition to the corrosion-resistant tape, in some other embodiments, the protective layer 5 can also be coated on the coating layer of the positive plate 1 or the negative plate 2, such as a ceramic coating, a wax coating, etc.

[0037] In an embodiment of the present disclosure, in the arrangement direction of the positive plate 1 and the negative plate 2, the projection of the protective layer 5 can cover the projection of the empty foil area 31. By designing in this way, the protection range of the protective layer 5 can be increased, and the above-mentioned metal deposition problem can be avoided to a greater extent, the protection effect of the protective layer 5 can be improved, and the problem of metal deposition caused by the reaction between the part of the plate located outside the edge of the protective layer 5 and the empty foil area 31 can be avoided.

[0038] The present disclosure does not limit the shape and size of the empty foil area 31 and the protective layer 5, for example, in an embodiment of the present disclosure, in the arrangement direction of the positive plate 1 and the negative plate 2, the projection of the empty foil area 31 can be a first rectangle 41, and the projection of the protective layer 5 can be a second rectangle 42, the length of the second rectangle 42 is a, and the width is b, the length of the first rectangle 41 is d, and the width is c, wherein b-c≥0.1mm, a-d≥1mm, specifically, b-c can be 0.1mm, 0.2mm, etc., and a-d can be 1mm, 2mm, etc. Here, the length and width can also refer to the arrow direction in Figure 2 By ensuring the size of b-c and a-d, the outer contour size of the protective layer 5 is greater than the outer contour size of the empty foil area 31, so that the protective layer 5 can cover the empty foil area 31 from both length and width dimensions, and the above-mentioned metal deposition problem can be avoided.

[0039] Since in the process of designing the battery cell, the most dangerous internal short circuit mode of the cell is the contact short circuit problem between the aluminum foil of the positive plate 1 and the negative plate 2. In order to avoid this risk, in an embodiment of the present disclosure, the empty foil area 31 can be formed on the negative plate 2, so that the positive plate 1 does not have an empty foil area 31, that is, there is no aluminum foil leakage problem, thereby completely eliminating the above-mentioned internal short circuit situation.

[0040] According to a second aspect of the present disclosure, there is provided an electric core including the battery pole core described above, since the electric core has all the beneficial effects of the battery pole core described above, which will not be repeated here.

[0041] According to a third aspect of the present disclosure, there is provided a battery including the electric core described above, since the battery has all the beneficial effects of the electric core described above, which will not be repeated here.

[0042] According to a fourth aspect of the present disclosure, there is provided a vehicle including the battery described above, since the vehicle has all the beneficial effects of the battery described above, which will not be repeated here.

[0043] In the above detailed description, reference is made to the accompanying drawings, which show, by way of illustration, specific aspects in which the disclosure can be practiced. In this regard, directional terminology, such as “central,” “longitudinal,” “lateral,” “length,” “width,” “thickness,” “upper,” “lower,” “front,” “back,” “left,” “right,” “vertical,” “horizontal,” “top,” “bottom,” “inner,” “outer,” “clockwise,” “counterclockwise,” “axial,” “radial,” “circumferential,” and like terms, are used herein, for clarity, relative to the views of the figures. Since components of the described devices can be positioned in a number of different orientations, the directional terminology can be used for purposes of explanation without limiting the scope of the disclosure. It is to be understood that other aspects can be utilized and structural or logical changes can be made without departing from the scope of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0044] It is to be understood that the features of the various aspects of the disclosure described herein can be combined with each other, unless specifically stated otherwise. As used herein, the term “and / or” includes any one of the associated listed terms, as well as any combination of any two or more of the associated listed terms; similarly, “at least one of’ includes any one of the associated listed terms, as well as any combination of any two or more of the associated listed terms.

[0045] It should be understood that, unless specifically stated otherwise, the terms “joined,” “attached,” “mounted,” “connected,” “linked,” “fixed,” and the like, as employed in the disclosure of the embodiments, should be given their broadest possible interpretation in light of the prior art to encompass any means for mechanically, electrically, and / or communicatively connecting two or more elements together, which can be directly connected, or connected by an intermediary, which can be made of one or more elements, which can be made of the same or different materials as the connected elements, which can be permanently or releasably connected, which can be mechanical, electrical, or communicative connections, and which can be internal or external to the elements connected thereto. The specific meaning of the above terms in the present context will be apparent to those skilled in the art, depending on the specific circumstances.

[0046] Further, the word "over" used in the context of a component, an element, or a material layer "over" another component, an element, or a material layer means that the component, element, or material layer is positioned, for example, placed, formed, deposited, etc. "indirectly" over the other component, element, or material layer such that one or more additional components, elements, or layers are arranged between the component, element, or material layer and the other component, element, or material layer. However, the word "over" used in the context of a component, an element, or a material layer "over" another component, an element, or a material layer also can optionally mean that the component, element, or material layer is positioned, for example, placed, formed, deposited, etc. "directly" over the other component, element, or material layer, for example, in direct contact with the other component, element, or material layer.

[0047] Although terms such as "first" and "second" can be used herein to describe various elements, components, regions, layers or sections, these elements, components, regions, layers or sections are not limited by these terms. Rather, these terms are used only to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, the first element, component, region, layer or section mentioned in the examples described herein can also be referred to as a second element, component, region, layer or section without departing from the teachings of the examples. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be construed as indicating or implying relative importance or an indicated number of the technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one of the features. In the description herein, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise explicitly and specifically limited.

[0048] It will be understood that the spatially relative terms, such as "above", "upper", "below", and "lower", are intended to be interpreted as the relative positions of one element to another element as shown in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientations depicted in the figures. For example, if a device in the figures is turned over, elements described as above other element would then be oriented below the other element. Accordingly, the term "above" encompasses both an orientation of above and below. The device can be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative terms used herein interpreted accordingly.

[0049] Furthermore, the word "exemplary" is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other aspects or designs. Rather, use of the word exemplary is intended to present concepts in a concrete manner. As used in this application, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless specified otherwise, or clear from context, "X employs A or B" is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then "X employs A or B" is satisfied under any of the foregoing instances. In addition, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form. Thus, use of the articles in this application and the following claims is not limiting.

[0050] Also, although the disclosure has been described with respect to only one or more implementations thereof, those skilled in the art will readily appreciate that other alternatives can be used. It is contemplated that the disclosure can be carried out in other specific ways than those expressly disclosed herein. Any and all such changes and modifications other than those already described and claimed are intended to be included within the scope of the disclosure. Specifically with respect to the various functions performed by the components (e.g., elements, resources, etc.) described above, unless otherwise specified, the terms used are intended to encompass any component which performs the specified function for an equivalent result. In addition, it is contemplated that various combinations or sub-combinations of the specific features and / or aspects of the disclosure can be made, and can be claimed, in any combination, as long as such features and / or aspects fall within the scope of the disclosure.

[0051] Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the features of the disclosure disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the disclosure being indicated by the following claims.

[0052] It is understood that the present disclosure is not limited to the precise structures herein described and illustrated in the drawings, and that various modifications and changes can be made therein without departing from the scope thereof. The scope of the present disclosure is limited only by the claims.

Claims

1. A battery electrode core, characterized in that, It includes multiple layers of positive electrode plates and multiple layers of negative electrode plates, wherein the multiple layers of positive electrode plates and multiple layers of negative electrode plates are arranged alternately. In this embodiment, at least one of the positive electrode and the negative electrode forms an empty foil region on its surface opposite to the other, and the empty foil region serves as an exhaust channel for the battery core.

2. The battery electrode core according to claim 1, characterized in that, At least one of the positive electrode and the negative electrode includes intermittently coated areas to form the empty foil area between two adjacent coated areas.

3. The battery electrode core according to claim 1, characterized in that, In the arrangement direction of the positive electrode and the negative electrode, the projection of the empty foil area is a first rectangle with a length of d and a width equal to the width of the corresponding positive electrode or the negative electrode, wherein 1mm≤d≤10mm.

4. The battery electrode core according to claim 1, characterized in that, An adjacent layer of the positive electrode and a layer of the negative electrode constitute a layer group, and there are multiple layer groups, each of which is provided with the empty foil area.

5. The battery electrode core according to claim 4, characterized in that, In each of the layer groups, there are multiple empty foil regions.

6. The battery electrode core according to any one of claims 1-5, characterized in that, One of the positive electrode and the negative electrode forms the empty foil area, and the surface of the other electrode has a protective layer at a position corresponding to the empty foil area to prevent metal deposition.

7. The battery electrode core according to claim 6, characterized in that, The protective layer is a corrosion-resistant tape adhered to the positive electrode or the negative electrode.

8. The battery electrode core according to claim 6, characterized in that, In the arrangement direction of the positive electrode and the negative electrode, the projection of the protective layer covers the projection of the empty foil area.

9. The battery electrode core according to claim 8, characterized in that, In the arrangement direction of the positive electrode and the negative electrode, the projection of the empty foil area is a first rectangle, and the projection of the protective layer is a second rectangle. The length of the second rectangle is a and the width is b. The length of the first rectangle is d and the width is c, where bc ≥ 0.1 mm and ad ≥ 1 mm.

10. The battery electrode core according to any one of claims 1-5, characterized in that, The empty foil region is formed on the negative electrode sheet.

11. A battery cell, characterized in that, Includes the battery electrode core according to any one of claims 1-10.

12. A battery, characterized in that, Includes the battery cell as described in claim 11.

13. A vehicle, characterized in that, Includes the battery as described in claim 12.

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