An all-solid-state battery
By using the stacked structure and elastic buffer layer design of the all-solid-state battery, the problems of high expansion rate and low safety are solved, achieving structural stability and improved safety, and extending the battery's lifespan.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- PHENIX NEW ENERGY (HUIZHOU) CO LTD
- Filing Date
- 2025-08-14
- Publication Date
- 2026-07-07
AI Technical Summary
Solid-state batteries suffer from high expansion rates and low safety, especially the expansion and micro-short circuit phenomena caused by lithium-ion deposition in the lithium metal anode, which affect the normal use and safety of the battery.
The structure adopts a stacked structure, which sets a accommodating groove and a protrusion on the solid electrolyte layer to enclose and install the positive and negative electrodes separately. An elastic buffer layer and an insulating protective layer are used to prevent the positive electrode active material from contacting the negative electrode active material, reduce the probability of lithium dendrite formation, absorb the expansion of the negative electrode, and improve the structural stability and safety.
It effectively prevents short circuits, reduces expansion rate, improves battery reliability and safety, and extends battery life.
Smart Images
Figure CN224472478U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of batteries, and more specifically, relates to an all-solid-state battery. Background Technology
[0002] Electrolytes in lithium-ion batteries can be divided into liquid electrolytes (containing liquid) and solid electrolytes (not containing liquid), i.e., liquid batteries and solid batteries. Compared to liquid batteries, solid batteries offer higher safety performance, higher energy density, higher power density, and better cycle stability. Due to these advantages, solid-state batteries have become a hot research topic and are considered the most promising direction for the development of next-generation high-energy-density lithium batteries.
[0003] However, solid-state batteries also have the problem of large expansion rate. Taking solid-state batteries with lithium metal as negative electrode as an example, the deposition of lithium ions to form lithium metal will cause the battery to expand during charging, resulting in an increase in internal thickness, which in turn can lead to bulging and cracking, affecting the normal use and safety of the battery. In addition, the active materials on the internal positive and negative electrode plates are prone to shedding and pulverization due to expansion and contraction. The internal structure of traditional stacked solid-state batteries does not have protective measures, which may cause the positive and negative electrode active materials and positive and negative current collectors to come into contact, resulting in micro-short circuits, thus posing certain safety hazards. Utility Model Content
[0004] In view of this, the purpose of this utility model is to provide an all-solid-state battery to solve the problems of low safety and high expansion rate of solid-state batteries in the prior art.
[0005] The objective of this utility model is achieved through the following technical solution.
[0006] A solid-state battery includes a casing and a solid-state battery body disposed inside the casing. The solid-state battery body includes a positive electrode portion, a solid electrolyte layer, and a negative electrode portion stacked sequentially. The solid electrolyte layer includes a first surface and a second surface facing each other. The first surface has a receiving groove, and the second surface has a protrusion. The positive electrode portion includes a positive electrode body and a positive electrode current collector. The positive electrode body is disposed in the receiving groove, and the positive electrode current collector is attached to the first surface of the solid electrolyte layer. The negative electrode portion includes a negative electrode body, a negative electrode current collector, and an elastic buffer layer. The elastic buffer layer has a cavity inside to accommodate the negative electrode body and the negative electrode current collector. The surface of the elastic buffer layer near the protrusion has an opening, and the protrusion seals the opening and abuts against the negative electrode body inside.
[0007] In the above scheme, the positive electrode is placed in the receiving groove and encapsulated in the receiving groove by the positive electrode current collector. The negative electrode and the negative electrode current collector are stacked in the cavity inside the elastic buffer layer, and the protrusion is inserted into the opening of the elastic buffer layer, thereby encapsulating the negative electrode and the negative electrode current collector inside the elastic buffer layer. By encapsulating the positive and negative electrodes separately, it is possible to effectively prevent the positive electrode active material and the positive electrode current collector from contacting the negative electrode active material and the negative electrode current collector, reducing the probability of lithium dendrite formation and effectively preventing short circuits. In addition, the elastic buffer layer is an elastic structure. When lithium ion deposition causes the negative electrode to expand, the elastic buffer layer can deform to buffer the expansion and absorb a certain amount of expansion thickness, which helps to reduce the expansion rate of the solid-state battery and improve its reliability.
[0008] In one example of this utility model, a protective layer is provided on the side of the negative electrode near the solid electrolyte layer; the protective layer is annular and located at the edge of the surface of the negative electrode; a pressing part is formed on the periphery of the opening of the elastic buffer layer to cooperate with the protective layer, and the pressing part abuts against the protective layer.
[0009] In the above scheme, the inner side of the clamping part abuts against the protective layer to avoid gaps, making the internal structure more compact and stable. The protective layer is a closed ring, which can block and inhibit the diffusion of lithium ions to the edge of the negative electrode, thereby effectively improving the service life of the solid-state battery.
[0010] In one example of this utility model, along the stacking direction, the projection of the positive electrode onto the negative electrode falls within the projection outline of the negative electrode; the protective layer is disposed on the surface of the negative electrode in a region that does not overlap with the projection of the positive electrode.
[0011] In the above scheme, along the stacking direction, the projection of the protective layer on the negative electrode does not overlap with the projection of the positive electrode, so as to avoid affecting the ion conduction between the positive and negative electrode facing each other, so as to avoid affecting the normal operation performance of the solid-state battery.
[0012] In one example of this invention, the protective layer is made of an insulating material.
[0013] In the above scheme, the protective layer is made of insulating material to avoid affecting the normal operation of the solid-state battery.
[0014] In one example of this invention, the elastic buffer layer is made of an elastic insulating material.
[0015] In the above scheme, the elastic buffer layer is made of insulating material to avoid affecting the normal operation of the solid-state battery. It is also elastic and can absorb the expansion generated by the negative electrode, thereby reducing the overall expansion rate of the solid-state battery.
[0016] In one example of this utility model, a connection hole is formed on the surface of the elastic buffer layer away from the protrusion.
[0017] In the above scheme, the negative current collector inside the elastic buffer layer is exposed through the connection hole so as to connect with the outside.
[0018] In one example of this utility model, a first connection port and a second connection port are respectively provided on two opposite sides of the outer shell.
[0019] In the above scheme, by opening a first connection port and a second connection port on the outer casing, the positive current collector and the negative current collector are exposed so as to be connected to the outside.
[0020] In one example of this utility model, the positive current collector is an aluminum foil, and the negative current collector is a copper foil.
[0021] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0022] The all-solid-state battery body of this invention adopts a stacked structure, which is compact and stable and can effectively prevent internal structural displacement.
[0023] This invention, by setting a receiving groove and a protrusion on the solid electrolyte layer, encloses and installs the positive electrode and the negative electrode separately, which can effectively prevent the positive electrode active material and the positive electrode current collector from contacting the negative electrode active material and the negative electrode current collector, reduce the probability of lithium dendrite formation, and effectively prevent short circuits, thus improving safety.
[0024] This invention features an elastic buffer layer. When lithium-ion deposition causes the negative electrode to expand, the elastic buffer layer can deform to buffer the expansion and absorb a certain amount of thickness, which helps to reduce the overall expansion rate of the solid-state battery and improve its reliability and safety. Attached Figure Description
[0025] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0026] Figure 1 This is a schematic diagram of the structure of an all-solid-state battery according to an embodiment of the present invention.
[0027] Explanation of the reference numerals in the figure:
[0028] 1-Outer shell; 11-First connection port; 12-Second connection port; 2-Positive electrode portion; 21-Positive electrode body; 22-Positive electrode current collector; 3-Solid electrolyte layer; 31-Accommodation groove; 32-Protrusion; 4-Negative electrode portion; 41-Negative electrode body; 411-Protective layer; 42-Negative electrode current collector; 43-Elastic buffer layer; 431-Pressure portion; 432-Connection hole. Detailed Implementation
[0029] To facilitate understanding of this invention, a more comprehensive description will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the invention. However, this invention can be implemented in many different forms and is not limited to the embodiments described herein.
[0030] Please refer to Figure 1 In a preferred embodiment, an all-solid-state battery is provided, comprising a casing 1 and a solid-state battery body disposed inside the casing 1. The solid-state battery body includes a positive electrode portion 2, a solid electrolyte layer 3, and a negative electrode portion 4 stacked sequentially. The solid electrolyte layer 3 includes a first surface and a second surface opposite to each other. A receiving groove 31 is provided on the first surface, and a protrusion 32 is provided on the second surface. The positive electrode portion 2 includes a positive electrode body 21 and a positive electrode current collector 22. The positive electrode body 21 is disposed in the receiving groove 31, and the positive electrode current collector 22 is attached to the first surface of the solid electrolyte layer 3. The negative electrode portion 4 includes a negative electrode body 41, a negative electrode current collector 42, and an elastic buffer layer 43. The elastic buffer layer 43 has a cavity inside to accommodate the negative electrode body 41 and the negative electrode current collector 42. An opening is provided on the surface of the elastic buffer layer 43 near the protrusion 32. The protrusion 32 seals the opening and abuts against the negative electrode body 41 inside.
[0031] It should be noted that, according to the direction shown in the figure, the bottom surface of the solid electrolyte layer 3 is the first surface, and the top surface is the second surface. The stacking direction described in this embodiment is the vertical direction shown in the figure.
[0032] Specifically, the positive electrode 21 is disposed in the receiving groove 31 and encapsulated in the receiving groove 31 by the positive current collector 22. The negative electrode 41 and the negative current collector 42 are stacked in the cavity inside the elastic buffer layer 43. The protrusion 32 is inserted into the opening at the bottom of the elastic buffer layer 43, thereby encapsulating the negative electrode 41 and the negative current collector 42 inside the elastic buffer layer 43. By encapsulating the positive electrode 21 and the negative electrode 41 separately, it is possible to effectively prevent the active material of the positive electrode 21 and the positive current collector 22 from contacting the active material of the negative electrode 41 and the negative current collector 42, reducing the probability of lithium dendrite formation and effectively avoiding short circuits. In addition, the elastic buffer layer 43 is an elastic structure. When lithium ion deposition causes the negative electrode 41 to expand, the elastic buffer layer 43 can deform to buffer the expansion and absorb a certain amount of expansion thickness, thereby helping to reduce the overall expansion rate of the solid-state battery, avoiding bulging and cracking, and improving reliability.
[0033] Preferably, the size of the protrusion 32 is the same as the size of the opening to ensure a sealing effect.
[0034] It should be noted that the negative electrode 41 is made of lithium metal or a lithium-containing material, and the positive electrode 21 and the solid electrolyte layer are both positive electrode 21 and solid electrolyte layer of existing solid-state batteries. The specific selection can be made according to actual needs.
[0035] It should be noted that the shape of the solid-state battery is not limited. For example, the shape of the solid-state battery can be a cuboid, a cube, a cylinder, etc. Correspondingly, the projection of the positive electrode 2, the solid electrolyte layer 3, and the negative electrode 4 in the stacking direction can be a rectangle, a square, or a circle. The shape of the receiving groove 31, the protrusion 32, the positive electrode 21, and the negative electrode 41 can also be a rectangle, a square, or a circle, depending on the actual needs.
[0036] Currently, to ensure the performance of solid-state batteries, the negative electrode area is usually larger than the positive electrode area. However, during storage or use, due to electric field distortion and interface defects, lithium-ion diffusion typically occurs in the peripheral area of the negative electrode facing the outer contour of the positive electrode, known as edge lithium-ion diffusion effect. This leads to a decrease in the overall performance of the solid-state battery and shortens its lifespan. In this embodiment, a protective layer 411 is provided on the side of the negative electrode 41 near the solid electrolyte layer 3. The protective layer 411 is annular and located at the edge of the surface of the negative electrode 41. A clamping part 431 is formed around the opening of the elastic buffer layer 43 to cooperate with the protective layer 411, and the clamping part 431 abuts against the protective layer 411.
[0037] The inner side of the pressing part 431 abuts against the protective layer 411 to avoid gaps, making the internal structure more compact and stable. The protective layer 411 is a closed ring, forming a groove that matches the protrusion 32 so that the protrusion 32 can contact the negative electrode 41. The protective layer 411 is tightly attached to the negative electrode 41. By influencing the edge electric field, blocking ion transport, and mechanical confinement, it prevents lithium ions from diffusing to the edge of the negative electrode 41, thereby effectively improving the service life of the solid-state battery.
[0038] Furthermore, along the stacking direction, the projection of the positive electrode 21 onto the negative electrode 41 falls within the projection outline of the negative electrode 41. The protective layer 411 is disposed on the surface of the negative electrode 41 in the area where it does not overlap with the projection of the positive electrode 21, so as not to affect the ion conduction between the positive electrode 21 and the negative electrode 41 in the opposite area, ensuring the normal operation performance of the solid-state battery. Correspondingly, the projection area of the protrusion 32 is the same as that of the positive electrode 21 in the stacking direction, which is beneficial to the transport of ions between the positive electrode 21 and the negative electrode 41.
[0039] In this embodiment, the protective layer 411 is made of an insulating material to avoid affecting the normal operation of the solid-state battery. It is understood that since the negative electrode 41 includes lithium metal, the protective layer 411 needs to be made of a material that does not react with lithium metal. For example, the protective layer 411 can be ceramic, polyimide or polypropylene.
[0040] Specifically, the protective layer 411 can be formed on the negative electrode 41 through processes such as coating, deposition, 3D printing, and chemical etching. These processes can strengthen the connection and bonding between the protective layer 411 and the surface of the negative electrode 41, thereby effectively blocking the diffusion of lithium ions.
[0041] In this embodiment, the elastic buffer layer 43 is made of an elastic insulating material to avoid affecting the normal operation of the solid-state battery. It is also elastic and can absorb and buffer the expansion generated by the negative electrode 41 through deformation, thereby reducing the overall expansion rate of the solid-state battery.
[0042] Specifically, the material of the elastic buffer layer 43 may be rubber or other composite materials that meet the requirements of elasticity and insulation.
[0043] In this embodiment, a connection hole 432 is provided on the top surface of the elastic buffer layer 43, through which the negative current collector 42 inside the elastic buffer layer 43 can be exposed so as to be connected to the outside.
[0044] Furthermore, the bottom surface of the outer casing 1 has a first connection port 11 and the top surface has a second connection port 12. The second connection port 12 is correspondingly provided with the connection hole 432 on the elastic buffer layer 43. By opening the first connection port 11 and the second connection port 12 on the outer casing 1, the positive current collector 22 and the negative current collector 42 are exposed so as to be connected to the outside.
[0045] Preferably, the positive current collector 22 is an aluminum foil and the negative current collector 42 is a copper foil. Alternatively, the positive current collector 22 can also be a carbon-coated aluminum foil and the negative electrode 41 can be a carbon-coated copper foil.
[0046] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0047] Furthermore, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0048] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.
[0049] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. An all-solid-state battery, characterized in that, The device includes a housing and a solid-state battery body disposed inside the housing. The solid-state battery body includes a positive electrode, a solid electrolyte layer and a negative electrode, which are stacked sequentially. The solid electrolyte layer includes a first surface and a second surface opposite to each other. The first surface is provided with a receiving groove, and the second surface is provided with a protrusion. The positive electrode portion includes a positive electrode body and a positive electrode current collector. The positive electrode body is disposed in the receiving groove, and the positive electrode current collector is attached to the first surface of the solid electrolyte layer. The negative electrode portion includes a negative electrode body, a negative electrode current collector, and an elastic buffer layer. The elastic buffer layer has a cavity inside to accommodate the negative electrode body and the negative electrode current collector. The surface of the elastic buffer layer near the protrusion has an opening. The protrusion seals the opening and abuts against the negative electrode body inside.
2. The all-solid-state battery according to claim 1, characterized in that, The negative electrode has a protective layer on the side close to the solid electrolyte layer; The protective layer is annular and is located at the edge of the surface of the negative electrode. The opening periphery of the elastic buffer layer forms a pressing part that cooperates with the protective layer, and the pressing part abuts against the protective layer.
3. The all-solid-state battery according to claim 2, characterized in that, Along the stacking direction, the projection of the positive electrode onto the negative electrode falls within the projection outline of the negative electrode; The protective layer is located on the surface of the negative electrode in a region that does not overlap with the projection of the positive electrode.
4. The all-solid-state battery according to claim 2, characterized in that, The protective layer is made of insulating material.
5. The all-solid-state battery according to claim 1, characterized in that, The elastic buffer layer is made of an elastic insulating material.
6. The all-solid-state battery according to claim 1, characterized in that, The elastic buffer layer has a connection hole on the surface away from the protrusion.
7. The all-solid-state battery according to claim 1, characterized in that, The outer shell has a first connection port and a second connection port on its two opposite sides, respectively.
8. The all-solid-state battery according to claim 1, characterized in that, The positive current collector is aluminum foil, and the negative current collector is copper foil.