Battery capable of automatically supplementing liquid
By designing a multi-layered electrolyte package in a lithium-ion battery, the problem of insufficient electrolyte is solved, timely replenishment of the electrolyte and stability of the cell performance are achieved, and the expansion pressure and safety of the cell are solved.
Patent Information
- Application Number
- CN202420267906.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-02-02
- Publication Date
- 2025-01-10
- Estimated Expiration
- 2034-02-02
AI Technical Summary
The electrolyte may be insufficient during the circulation of lithium-ion batteries, which may increase the ion resistance of the battery cell, affect the kinetic performance, and may lead to safety problems such as lithium extraction. The existing technology is difficult to effectively solve the problem of insufficient electrolyte in the later stage.
Design an automatic rehydration battery, including a multi-layer structure electrolyte package. The electrolyte package breaks layer by layer when expanding and extruding inside the battery, and replenishes the electrolyte of the charging core in time to ensure sufficient electrolyte.
Through the multi-layer structure electrolyte package design, the electrolyte can be gradually replenished in the later stage of the battery cycle, preventing the expansion pressure of the battery cell from being too large, extending the cycle life of the battery cell, and improving safety.
Smart Images
Figure CN222338457U_ABST
Abstract
Description
Technical Field
[0001] The present application mainly relates to the field of battery technology, and in particular to an automatic liquid-refilling battery. Background Art
[0002] Lithium-ion batteries have been widely used in electric vehicles and energy storage due to their high energy density and long cycle life. Commonly used battery cells are divided into winding and stacking. In the early stage of winding, winding batteries use a winding needle to drive the positive and negative electrode separators to wind together. At present, during the use of lithium-ion batteries, two injections after formation are usually used to ensure that there is sufficient electrolyte in the battery cell. Although the market has higher and higher requirements for battery cell life, the battery cell is in a state of lack of liquid due to the possibility of reaction, decomposition and consumption of electrolyte during the cycle process, which will increase the ionic resistance of the battery cell, affect the kinetic performance of the battery cell, and may cause lithium precipitation and other phenomena, thereby causing the battery cell capacity to drop and causing battery cell safety problems.
[0003] As the battery cell cycles, electrolyte consumption and side reactions lead to thickening of the SEI film, poor adhesion of the negative electrode material, and increased expansion rate of the binder gel, which will increase the thickness of the battery cell. The increase in battery cell thickness will increase the expansion force of the battery cell, resulting in poor battery cell dynamics, which may lead to lithium precipitation and other phenomena, thus causing battery cell safety and other problems. The existing technology usually uses secondary injection of the battery cell to ensure the injection volume of the battery cell, but there is still no way to solve the problem of insufficient electrolyte in the late stage of the cycle. Utility Model Content
[0004] The technical problem to be solved by the present application is to provide a battery with automatic liquid replenishment, which can replenish the electrolyte of the battery cell in time to ensure that there is sufficient electrolyte in the later cycle of the battery cell.
[0005] To solve the above technical problems, the present application provides a battery comprising: a first electrolyte package located at the center of the battery, the first electrolyte package comprising a first outer layer, a second outer layer, a first inner layer and a second inner layer, the first outer layer surrounds the second outer layer from the outside, the second outer layer surrounds the first inner layer and the second inner layer from the outside, and the first inner layer and the second inner layer are arranged opposite to each other; a winding core, the winding starting point of the core is the first electrolyte package, and the core surrounds the first electrolyte package from the outside in the battery; and a battery cell shell for accommodating the core and the first electrolyte package.
[0006] Optionally, the first outer layer and / or the second outer layer electrolyte includes a laminated structure of greater than or equal to two layers.
[0007] Optionally, the winding core comprises a membrane, and the membrane is clamped at one end of the winding starting point and is located between the first inner layer and the second inner layer.
[0008] Optionally, the inner wall and the outer wall of the first electrolyte bag do not react with the electrolyte in the battery and are elastic.
[0009] Optionally, the first outer layer, the second outer layer, the first inner layer and / or the second inner layer each have one or more first openings, and the first electrolyte package is suitable for rupturing from the first opening when the internal pressure of the battery reaches a critical value.
[0010] Optionally, at least some of the first openings are adapted to withstand different upper pressure limits.
[0011] Optionally, the battery further includes a second electrolyte package located between the winding core and the battery cell casing.
[0012] Optionally, the second electrolyte package includes a single-layer and / or multi-layer laminated structure.
[0013] Optionally, each of the single layers in the second electrolyte package or the stacked structure has one or more second openings, and the second electrolyte package is suitable for rupturing from the second openings when the internal pressure of the battery reaches a critical value.
[0014] Optionally, at least some of the second openings are adapted to withstand different upper pressure limits.
[0015] Compared with the prior art, the present application arranges an electrolyte package with a multi-layer structure inside the battery, so that the electrolyte package is expanded, squeezed and ruptured layer by layer in the later stage of the battery cycle. The battery cell electrolyte can be replenished in time in different cycles to ensure that the battery cell has sufficient electrolyte in the later cycle. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:
[0017] Figure 1 It is a structural schematic diagram of a battery with automatic liquid replenishment in one embodiment of the present application;
[0018] Figure 2 is a schematic structural diagram of a first electrolyte package in one embodiment of the present application;
[0019] Figure 3 is a schematic structural diagram of a battery with automatic liquid replenishment in another embodiment of the present application; DETAILED DESCRIPTION
[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.
[0021] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.
[0022] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values of the parts and steps set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant field may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so that once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.
[0023] In the description of the present application, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction, and therefore cannot be understood as limiting the scope of protection of the present application; the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.
[0024] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.
[0025] In addition, it should be noted that the use of words such as "first" and "second" to define components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above words have no special meaning and cannot be understood as limiting the scope of protection of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.
[0026] This application refers to Figure 1 An automatic refilling battery 10 (hereinafter referred to as "battery 10") is shown, which can replenish the electrolyte of the battery cell in time to ensure that the electrolyte of the battery cell is sufficient in the later cycle.
[0027] according to Figure 1 The battery 10 mainly includes a first electrolyte package 101, a winding core 102 and a battery shell 103. Specifically, the first electrolyte package 101 is located at the center of the battery 10; the battery 10 is prepared by a winding method, under which the winding starting point of the winding core 102 is the first electrolyte package 101, and the winding core 102 surrounds the first electrolyte package 101 from the outside in the battery 10; the battery shell 103 is used to accommodate the winding core 102 and the first electrolyte package 101.
[0028] In order to more clearly understand the structure of the battery 10, now refer to Figure 2 The specific structure of the first electrolyte package 101 is described in detail. Figure 2As shown, the first electrolyte package 101 includes a first outer layer 1011, a second outer layer 1012, a first inner layer 1013 and a second inner layer 1014, the first outer layer 1011 surrounds the second outer layer 1012 from the outside, the second outer layer 1012 surrounds the first inner layer 1013 and the second inner layer 1014 from the outside, and the first inner layer 1013 and the second inner layer 1014 are arranged opposite to each other.
[0029] The winding core 102 includes a diaphragm (not shown). In this embodiment, preferably, the diaphragm is clamped at one end of the winding start point of the winding core 102 and is located between the first inner layer 1013 and the second inner layer 1014 (i.e. Figure 2 The battery 100 of the present application no longer needs the winding needle structure of the prior art, and the winding process can also be completed in the above manner.
[0030] In this embodiment, since the diaphragm in the winding core 102 is located between the first inner layer 1013 and the second inner layer 1014 at the starting point of the winding of the winding core 102, the first inner layer 1013 and the second inner layer 1014 can play the same role as the winding needle. However, by such a replacement, the step of removing the winding needle from the battery cell after the battery preparation is completed can be omitted in the battery manufacturing process, saving preparation time and simplifying the preparation process. In addition, the first inner layer 1013 and the second inner layer 1014 will remain inside the battery cell after the battery 10 completes the winding process, so they do not need to be separated from the diaphragm after the winding process is completed, which can avoid friction between the winding needle and the diaphragm when it is detached, thereby avoiding damage to the diaphragm and improving the stability and reliability of the battery.
[0031] Furthermore, the inner and outer walls of the first electrolyte package 101 do not react with the electrolyte in the battery and are elastic, and materials such as PET, PC, DHPE and PP can generally be used. Since the inner and outer walls of the first electrolyte package 101 are both elastic structures, in the later stage of the battery 10 cycle, as the expansion of the battery cell increases, the first electrolyte package 101 can be gradually ruptured by the expansion pressure inside the battery cell, and the electrolyte pre-filled in the first electrolyte package 101 flows out, achieving the effect of replenishing the battery cell. At the same time, due to the rupture of the first electrolyte package 101, a part of the space can also be released, alleviating the impact of the battery cell expansion on the internal space of the battery cell.
[0032] More specifically, the first outer layer 1011, the second outer layer 1012, the first inner layer 1013 and / or the second inner layer 1014 each have one or more first openings. Therefore, the first electrolyte package 101 is suitable for rupturing from the first openings on each layer when the internal pressure of the battery reaches a critical value. In this embodiment, the first openings of the first outer layer 1011, the second outer layer 1012, the first inner layer 1013 and the second inner layer 1014 are suitable for bearing different upper limits of pressure, and the first outer layer 1011 and / or the second outer layer 1012 include a laminated structure greater than or equal to two layers, which can generally be a structure of 0 to 10 layers. Therefore, in the later stage of the battery 10 cycle, the first outer layer 1011 and the second outer layer 1012 can be ruptured layer by layer under the compression of the internal expansion force of the battery cell; and when the first outer layer 1011 and the second outer layer 1012 are both ruptured, the first inner layer 1013 and the second inner layer 1014 will also rupture under compression. The multi-layer structure can ensure that the first electrolyte package 101 can be gradually damaged to release electrolyte and space at different stages in the later stages of the battery cycle, and can prevent the first electrolyte package 101 from collapsing all at once, leading to the problem of unstable internal structure. Therefore, the design of the multi-layer structure can limit the maximum pressure inside the battery cell, and can replenish the electrolyte in time in the later stages of the battery cell cycle, thereby ensuring the performance of the battery cell.
[0033] Since the temperature rise of the center of the battery cell is relatively large during the charge and discharge process, there are relatively more side reactions in the center of the battery cell. Preventing the first electrolyte package 101 in the center of the battery 10 can effectively alleviate the lack of electrolyte in the center of the battery cell in the later stage. Since the first electrolyte package 101 will gradually break and release the space in the center of the battery cell, it can also alleviate the pressure on the battery 10 due to the expansion of the battery cell. In some cases, the outer ring of the battery cell may also be short of liquid. Therefore, in another preferred embodiment of the present application, an electrolyte package is also arranged between the winding core and the battery cell shell to solve the problem of lack of electrolyte in the outer ring of the battery cell.
[0034] Reference Figure 3 In other embodiments of the present application, an automatic refilling battery 20 (hereinafter referred to as "battery 20") is provided, and the battery 20 includes a first electrolyte package 201, a core 202, a battery shell 203, and a second electrolyte package 204. The first electrolyte package 201, the core 202, and the battery shell 203 have the same structure as an electrolyte package 101, a core 102, and a battery shell 103 in the battery 10, and will not be described in detail here.
[0035] The battery 20 also includes a second electrolyte bag 204, which is located between the core 202 and the battery cell housing 203. The second electrolyte bag 204 includes a single-layer and / or multi-layer laminated structure, which can be 0-10 layers. Each of the single-layer or laminated structures in the second electrolyte bag 204 has one or more second opening positions, and the second electrolyte bag 204 is suitable for rupturing from the second opening position when the internal pressure of the battery reaches a critical value. In this embodiment, when the second electrolyte bag 204 is a laminated structure, the second opening position on each layer is suitable for withstanding different upper limits of pressure. Therefore, in the later stage of the battery 20 cycle, after the battery cell gradually expands, the second electrolyte bag 204 will also rupture layer by layer to replenish the electrolyte to the outside of the battery cell. At the same time, when the second electrolyte bag 204 ruptures, a portion of the space between the core 202 and the battery cell housing 203 will be released to relieve the spatial pressure of the battery cell expansion.
[0036] The combined use of the first electrolyte package 201 and the second electrolyte package 202 can effectively alleviate the expansion and liquid shortage inside and outside the battery cell, which is beneficial to the long cycle performance of the battery cell.
[0037] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.
[0038] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.
[0039] Similarly, it should be noted that in order to simplify the description of the disclosure of this application and thus help understand one or more application embodiments, in the above description of the embodiments of this application, multiple features are sometimes merged into one embodiment, figure or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than the features mentioned in the claims. In fact, the features of the embodiments are less than all the features of the single embodiment disclosed above.
[0040] In some embodiments, numbers describing the number of components and attributes are used. It should be understood that such numbers used in the description of the embodiments are modified by the modifiers "about", "approximately" or "substantially" in some examples. Unless otherwise specified, "about", "approximately" or "substantially" indicate that the numbers are allowed to vary by ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, which may change according to the required features of individual embodiments. In some embodiments, the numerical parameters should take into account the specified significant digits and adopt the general method of retaining digits. Although the numerical domains and parameters used to confirm the breadth of their range in some embodiments of the present application are approximate values, in specific embodiments, the setting of such numerical values is as accurate as possible within the feasible range.
[0041] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the claims of the present application.
Claims
1. A battery with automatic liquid replenishment, characterized in that: include: A first electrolyte bag, located at the center of the battery, the first electrolyte bag comprising a first outer layer, a second outer layer, a first inner layer and a second inner layer, the first outer layer surrounds the second outer layer from the outside, the second outer layer surrounds the first inner layer and the second inner layer from the outside, and the first inner layer and the second inner layer are arranged opposite to each other; A winding core, the winding starting point of the winding core is the first electrolyte package, and the winding core surrounds the first electrolyte package from the outside in the battery; as well as A battery cell casing is used to accommodate the winding core and the first electrolyte package.
2. The battery according to claim 1, characterized in that The first outer layer and / or the second outer layer includes a laminated structure greater than or equal to two layers.
3. The battery according to claim 1, characterized in that The winding core includes a membrane, and one end of the membrane at the winding start point is sandwiched between the first inner layer and the second inner layer.
4. The battery according to claim 1, characterized in that The inner wall and the outer wall of the first electrolyte bag do not react with the electrolyte in the battery and have elasticity.
5. The battery according to claim 1, characterized in that The first outer layer, the second outer layer, the first inner layer and / or the second inner layer each have one or more first openings, and the first electrolyte package is suitable for rupturing from the first openings when the internal pressure of the battery reaches a critical value.
6. The battery according to claim 5, characterized in that At least some of the first openings are adapted to withstand different upper pressure limits.
7. The battery according to any one of claims 1 to 6, characterized in that: Also included is a second electrolyte package located between the winding core and the battery cell casing.
8. The battery according to claim 7, characterized in that The second electrolyte package includes a single-layer and / or multi-layer laminated structure.
9. The battery according to claim 8, characterized in that The single layer in the second electrolyte package or each of the stacked structures has one or more second openings, and the second electrolyte package is suitable for being broken from the second openings when the internal pressure of the battery reaches a critical value.
10. The battery according to claim 9, characterized in that At least some of the second openings are adapted to withstand different upper pressure limits.