Solid-state battery electrolyte assembly and solid-state battery
By setting an isolation layer between the electrolyte layers of a solid-state battery and using thermally responsive materials to melt and block lithium-ion transport at high temperatures, the problem of thermal runaway in solid-state batteries is solved, improving battery safety and lifespan.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- QINGTAO (KUNSHAN) ENERGY DEV CO LTD
- Filing Date
- 2025-06-27
- Publication Date
- 2026-07-03
Smart Images
Figure CN224458150U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of solid-state battery technology, and in particular to a solid-state battery electrolyte assembly and a solid-state battery. Background Technology
[0002] Currently, most new energy vehicles use lithium-ion batteries, which traditionally use liquid electrolytes. However, lithium-ion batteries using liquid electrolytes have drawbacks such as the flammability of liquid organic electrolytes and the formation of lithium dendrites during charging. These drawbacks affect the battery's performance and lifespan. Batteries using solid-state electrolytes have higher energy density and reduce many of the safety risks associated with liquid electrolytes.
[0003] Solid-state batteries use a solid electrolyte to separate the electrodes, with no membrane between them. Although a solid electrolyte replaces the liquid electrolyte, unavoidable battery defects and material side reactions can still cause heat buildup inside the battery, potentially leading to thermal runaway and other problems. Utility Model Content
[0004] This invention aims to solve at least one of the technical problems existing in the prior art. To this end, this invention proposes a solid-state battery electrolyte assembly and a solid-state battery to address the problem of thermal runaway that currently plagues solid-state batteries.
[0005] In a first aspect, the present invention provides a solid-state battery electrolyte assembly, the solid-state battery electrolyte assembly comprising a first solid-state electrolyte layer, an isolation layer and a second solid-state electrolyte layer;
[0006] The first solid electrolyte layer and the second solid electrolyte layer are respectively attached to the two opposite sides of the insulating layer;
[0007] The isolation layer is configured to melt at high temperature to block lithium-ion transport;
[0008] The isolation layer includes a support structure with open channels and a thermally responsive material filled within the channel structure; or,
[0009] The isolation layer includes a support structure made of a low-melting-point polymer electrolyte and an insulating material filled within the support structure.
[0010] In one embodiment of the solid-state battery electrolyte assembly described above, the thickness of the separator layer in the direction perpendicular to the first solid-state electrolyte layer and the second solid-state electrolyte layer is 0.5 μm to 10 μm.
[0011] In one embodiment of the solid-state battery electrolyte assembly described above, the support structure is a three-dimensional mesh structure.
[0012] In one embodiment of the solid-state battery electrolyte assembly described above, the support structure has a channel penetrating through the support structure, and the channel is perpendicular to the first solid-state electrolyte layer and the second solid-state electrolyte layer.
[0013] In one embodiment of the solid-state battery electrolyte assembly described above, an ion-conducting layer is provided within the pores.
[0014] In one embodiment of the solid-state battery electrolyte assembly described above, the insulating layer has the same shape and size as the first solid-state electrolyte layer and the second solid-state electrolyte layer.
[0015] The separator layer has the same shape and size as the first and second solid electrolyte layers on both sides. It can melt at high temperature to effectively block the lithium-ion transport between the first and second solid electrolyte layers, while avoiding the formation of gaps between the first and second solid electrolyte layers, which would increase the resistance of the solid battery due to air in the gaps.
[0016] In one embodiment of the solid-state battery electrolyte assembly described above, both the first solid-state electrolyte layer and the second solid-state electrolyte layer partially extend beyond the insulating layer.
[0017] In one embodiment of the solid-state battery electrolyte assembly described above, the thickness of both the first solid-state electrolyte layer and the second solid-state electrolyte layer in the direction perpendicular to the first solid-state electrolyte layer is 10 μm to 200 μm.
[0018] In one embodiment of the solid-state battery electrolyte assembly described above, the first solid-state electrolyte layer and the second solid-state electrolyte layer have different thicknesses in the direction perpendicular to the first solid-state electrolyte layer and the second solid-state electrolyte layer.
[0019] In a second aspect, this application provides a solid-state battery, the solid-state battery including a positive electrode, a negative electrode, and a solid-state battery electrolyte assembly as described in any one of the first aspects, the solid-state battery electrolyte assembly being disposed between the positive electrode and the negative electrode.
[0020] This utility model has the following advantages:
[0021] The solid-state battery electrolyte assembly provided in this application divides the solid electrolyte into a first solid-state electrolyte layer and a second solid-state electrolyte layer, and sets an isolation layer between the first solid-state electrolyte layer and the second solid-state electrolyte layer. At high temperature, the isolation layer melts and blocks the lithium-ion transport between the first solid-state electrolyte layer and the second solid-state electrolyte layer, thereby cutting off the battery circuit at high temperature and avoiding thermal runaway of the solid-state battery.
[0022] By placing the separator layer between the first solid electrolyte layer and the second solid electrolyte layer, on the one hand, at low temperatures, the positive and negative electrodes can directly contact the first and second solid electrolyte layers respectively to carry out lithium-ion cross-transport, which can reduce the impact on the battery operation at low temperatures. The solid electrolyte layer separates the separator layer from the electrode layer to prevent side reactions. On the other hand, the first and second solid electrolyte layers can also provide some support for the separator layer, which helps to maintain the shape and structural stability of the separator layer. Attached Figure Description
[0023] The disclosure of this utility model will become more readily understood with reference to the accompanying drawings. It will be readily understood by those skilled in the art that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this utility model. Furthermore, similar numbers in the drawings are used to denote similar components, wherein:
[0024] Figure 1 This is a structural diagram of a solid electrolyte assembly provided in one embodiment of this application.
[0025] Explanation of reference numerals in the attached figures
[0026] 1. First solid electrolyte layer; 2. Isolation layer; 3. Second solid electrolyte layer. Detailed Implementation
[0027] Some embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.
[0028] As described in the background section, traditional lithium batteries use liquid electrolytes. However, lithium batteries using liquid electrolytes have drawbacks such as lithium dendrite formation during charging and the flammability of liquid organic electrolytes. Currently, solid-state batteries using solid electrolytes have been developed due to their higher energy density and higher safety. However, solid-state batteries also have the problem of thermal runaway caused by heat accumulation inside the battery.
[0029] To address the aforementioned issues, this application creatively proposes a solid-state battery electrolyte assembly and a solid-state battery. An isolation layer is disposed within the solid-state electrolyte layer. At high temperatures, the isolation layer melts and blocks lithium-ion transport between the two solid-state electrolyte layers, thereby cutting off the battery circuit at high temperatures and preventing thermal runaway in the solid-state battery.
[0030] Furthermore, placing the separator between the first and second solid electrolyte layers has several advantages. First, at low temperatures, the positive and negative electrodes can directly contact the first and second solid electrolyte layers respectively to facilitate lithium-ion exchange, which reduces the impact on battery operation at low temperatures. The solid electrolyte layer separates the separator from the electrode layer, preventing side reactions. Second, the first and second solid electrolyte layers can also provide some support for the separator, helping to maintain its shape and structural stability.
[0031] The present invention will be specifically described below through specific embodiments.
[0032] Specifically, this application provides a solid-state battery electrolyte assembly, referring to... Figure 1 As shown, the solid-state battery electrolyte assembly includes a first solid-state electrolyte layer 1, an isolation layer 2, and a second solid-state electrolyte layer 3; the first solid-state electrolyte layer 1 and the second solid-state electrolyte layer 3 are respectively attached to opposite sides of the isolation layer 2; the isolation layer 2 is configured to melt at high temperature to block lithium-ion transport.
[0033] The solid-state battery electrolyte assembly provided in this application divides the solid electrolyte into a first solid-state electrolyte layer 1 and a second solid-state electrolyte layer 3, and sets an isolation layer 2 between the first solid-state electrolyte layer 1 and the second solid-state electrolyte layer 3. At low temperatures and normal battery operating temperatures, lithium-ion transport between the first solid-state electrolyte layer 1 and the second solid-state electrolyte layer 3 can be carried out normally through the isolation layer 2. When the temperature of the solid-state battery rises to a certain temperature (the melting point of the thermal response material of the isolation layer 2), the isolation layer 2 melts and blocks the lithium-ion transport between the first solid-state electrolyte layer 1 and the second solid-state electrolyte layer 3, thereby cutting off the circuit of the solid-state battery at high temperatures and preventing thermal runaway of the solid-state battery.
[0034] In some embodiments, the isolation layer 2 includes a support structure having open pores and a thermally responsive material filled in the pore structure.
[0035] Thermally responsive materials are smart materials capable of reacting to localized temperature changes. In this application, a thermally responsive material refers to a material that melts when the ambient temperature reaches a specified critical value (less than the thermal runaway temperature of a solid-state battery but significantly greater than its normal operating temperature), thereby significantly reducing the lithium-ion transport rate or even completely blocking lithium-ion transport. For example only, a thermally responsive material can be a hot-melt material, specifically one or more mixtures of paraffin wax, low-melting-point alloys, and thermoplastic polymers. The melting point and softening point of the aforementioned thermally responsive material at high temperatures are 60°C to 150°C.
[0036] The thermally responsive material can be paraffin wax. After paraffin wax melts at its melting point, its fluidity increases, which can block the transport of lithium ions between the two solid electrolyte layers.
[0037] Of course, thermally responsive materials can also be such as halide solid electrolytes like Li2ZrCl6, which undergo a phase transition at high temperatures, resulting in a decrease in lithium-ion transport rate.
[0038] The support structure can still support the first solid electrolyte layer 1 and the second solid electrolyte layer 3 after the thermal response material melts, thus preventing the first solid electrolyte layer 1 and the second solid electrolyte layer 3 from tilting and contacting each other when the thermal response material melts, which would reduce the blocking effect of the thermal response material in the isolation layer 2 on lithium ions.
[0039] In some embodiments, the isolation layer 2 includes a support structure made of a low-melting-point polymer electrolyte and an insulating material filled within the support structure. At high temperatures, the support structure melts, working in conjunction with the insulating material to block lithium-ion transport.
[0040] For example, the low-melting-point polymer electrolyte comprises one or more of polyethylene, PE, polypropylene, PP, and polyvinylidene fluoride (PVDF), and is doped with lithium salt. It can conduct lithium ions at low temperatures and melts at high temperatures, thus providing insulation.
[0041] The preparation method can be electrospinning.
[0042] For example, the insulating material can be Al2O3, SiO2, Si3N4, etc., and this application does not impose any restrictions.
[0043] In some embodiments, the thickness of the isolation layer 2 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 (X direction) is 0.5 μm to 10 μm. Optionally, the thickness of the isolation layer 2 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 can be 0.5 μm, 1 μm, 1.5 μm, 2 μm, 2.5 μm, 3 μm, 3.5 μm, 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm, 10 μm, or any value within the above range.
[0044] The thickness of the isolation layer 2 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 is controlled between 0.5 μm and 10 μm. It can effectively block the lithium-ion transport between the first solid electrolyte layer 1 and the second solid electrolyte layer 3 at high temperatures, and shorten the lithium-ion transport distance between the first solid electrolyte layer 1 and the second solid electrolyte layer 3. This ensures normal lithium-ion transport between the first solid electrolyte layer 1 and the second solid electrolyte layer 3 at low temperatures, and keeps the resistance of the solid battery within the normal range.
[0045] In some embodiments, the support structure can be a three-dimensional mesh structure, which serves both as a support and can accommodate a large amount of thermally responsive material. It also allows the thermally responsive material to be evenly distributed within the support structure to a certain extent, ensuring the rapid formation of a large-area barrier layer under high-temperature conditions to prevent lithium-ion transport. This application does not impose specific limitations on the material of the support structure. For example, the support structure can be a non-woven fabric support structure.
[0046] In some embodiments, the support structure has a through-hole that penetrates the support structure and is perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3.
[0047] The support structure has a through-hole in a direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3. When the temperature rises and the internal thermal response material melts, the thermal response material can be quickly discharged. The thermal response material comes into contact with the first solid electrolyte layer 1 and the second solid electrolyte layer 3 at the first moment, so as to block the transmission of lithium ions between the first solid electrolyte layer 1 and the second solid electrolyte layer 3 on both sides.
[0048] In some embodiments, an ion-conducting layer is disposed within the pore, preferably on the pore wall of the pore, and the ion-conducting layer includes a solid electrolyte to enable lithium ion conduction at low temperatures.
[0049] In some embodiments, the isolation layer 2 has the same shape and size as the first solid electrolyte layer 1 and the second solid electrolyte layer 3.
[0050] The isolation layer 2 has the same shape and size as the first solid electrolyte layer 1 and the second solid electrolyte layer 3 on both sides. It can melt at high temperature to effectively block the lithium-ion transmission between the first solid electrolyte layer 1 and the second solid electrolyte layer 3, while avoiding the formation of gaps between the first solid electrolyte layer 1 and the second solid electrolyte layer 3, which would increase the resistance of the solid battery due to the air in the gaps.
[0051] In some embodiments, both the first solid electrolyte layer 1 and the second solid electrolyte layer 3 partially extend out of the isolation layer 2.
[0052] Both the first solid electrolyte layer 1 and the second solid electrolyte layer 3 extend partially beyond the isolation layer 2. That is, the size of the isolation layer 2 is smaller than the size of the first solid electrolyte layer 1 and the second solid electrolyte layer 3. The isolation layer 2 can melt at high temperature to effectively block the lithium-ion transport between the first solid electrolyte layer 1 and the second solid electrolyte layer 3, while reducing the cost of the isolation layer 2.
[0053] In some embodiments, the thickness of both the first solid electrolyte layer 1 and the second solid electrolyte layer 3 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 (X-direction) is 10 μm to 200 μm. Optionally, the thickness of the first solid electrolyte layer 1 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 can be 10 μm, 20 μm, 40 μm, 50 μm, 60 μm, 70 μm, 90 μm, 110 μm, 140 μm, 160 μm, 190 μm, 200 μm, or specific values within the above ranges. Similarly, the thickness of the second solid electrolyte layer 3 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 (X-direction) can be 10 μm, 30 μm, 60 μm, 80 μm, 100 μm, 120 μm, 130 μm, 150 μm, 180 μm, 200 μm, or specific values within the above ranges.
[0054] The thickness of the first solid electrolyte layer 1 and the second solid electrolyte layer 3 is 10μm to 200μm, which can isolate the separator layer 2 from other components in the solid battery, reduce the direct contact and interaction between the separator layer 2 and electrode materials, reduce the probability of side reactions, thereby slowing down the aging rate of the separator layer 2 and extending the battery's service life.
[0055] The thicknesses of the first solid electrolyte layer 1 and the second solid electrolyte layer 3 in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3 can be the same or different.
[0056] In some embodiments, the first solid electrolyte layer 1 and the second solid electrolyte layer 3 have different thicknesses in the direction perpendicular to the first solid electrolyte layer 1 and the second solid electrolyte layer 3.
[0057] This application also provides a solid-state battery, which includes a positive electrode, a negative electrode, and a solid-state battery electrolyte assembly as described in any of the above embodiments, wherein the solid-state battery electrolyte assembly is disposed between the positive electrode and the negative electrode.
[0058] A solid-state battery may contain one set of solid-state battery electrolyte components, or two or more sets of solid-state battery electrolyte components. When a solid-state battery contains two or more sets of solid-state battery electrolyte components, an isolation layer 2 is provided between the solid-state battery electrolyte components to isolate the solid electrolyte layers in different sets of solid-state battery electrolyte components, thereby blocking lithium-ion transport between different sets of solid-state battery electrolyte components at high temperatures.
[0059] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0060] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.
[0061] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.
Claims
1. A solid-state battery electrolyte assembly, characterized by, The solid-state battery electrolyte assembly includes a first solid-state electrolyte layer, an isolation layer, and a second solid-state electrolyte layer; The first solid electrolyte layer and the second solid electrolyte layer are respectively attached to the two opposite sides of the insulating layer; The isolation layer is configured to block lithium-ion transport at high temperatures; The isolation layer includes a support structure with open channels and a thermally responsive material filled within the channel structure; or, The isolation layer includes a support structure made of a low-melting-point polymer electrolyte and an insulating material filled within the support structure.
2. The solid-state battery electrolyte assembly of claim 1, wherein, The thickness of the isolation layer in the direction perpendicular to the first solid electrolyte layer and the second solid electrolyte layer is 0.5 μm to 10 μm.
3. The solid-state battery electrolyte assembly of claim 1 or 2, wherein, The supporting structure is a three-dimensional mesh structure.
4. The solid-state battery electrolyte assembly of claim 1 or 2, wherein, The support structure has a through-hole that runs through it, and the through-hole is perpendicular to the first solid electrolyte layer and the second solid electrolyte layer.
5. The solid-state battery electrolyte assembly of claim 4, wherein, An ion-conducting layer is provided inside the pore.
6. The solid-state battery electrolyte assembly of claim 1, wherein, The isolation layer has the same shape and size as the first solid electrolyte layer and the second solid electrolyte layer.
7. The solid-state battery electrolyte assembly of claim 1, wherein, Both the first solid electrolyte layer and the second solid electrolyte layer partially extend out of the isolation layer.
8. The solid-state battery electrolyte assembly according to claim 1, characterized in that, The thickness of both the first solid electrolyte layer and the second solid electrolyte layer in the direction perpendicular to the first solid electrolyte layer is 10 μm to 200 μm.
9. The solid-state battery electrolyte assembly of claim 8, wherein, The first solid electrolyte layer and the second solid electrolyte layer have different thicknesses in the direction perpendicular to the first solid electrolyte layer and the second solid electrolyte layer.
10. A solid state battery, characterized by, The solid-state battery includes a positive electrode, a negative electrode, and a solid-state battery electrolyte assembly as described in any one of claims 1-9, wherein the solid-state battery electrolyte assembly is disposed between the positive electrode and the negative electrode.