In-grown self-heating tab adapted for multi-system solid-state battery

Abstract

The application provides an endogenous self-heating pole piece suitable for a multi-system solid-state battery, which is suitable for the interior of a polymer, sulfide or oxide three-type solid-state battery, and comprises, from bottom to top, a pole piece layer, an insulating support base material layer, an electric heating layer, a conductive circuit layer, a sealing isolation protection layer and the pole piece layer; the insulating support base material layer, the electric heating layer and the conductive circuit layer are encapsulated to form an integral independent heating loop; the insulating support base material layer and the sealing isolation protection layer are both provided with the pole piece layer, the pole piece layer is in contact with an electrolyte to form an energy storage output loop; and the independent heating loop integrated in the electrode and the energy storage output loop are electrically isolated from each other through the sealing isolation protection layer. The independent closed heating loop integrated in the electrode directly and accurately heats the electrolyte layer from the interior of the battery cell, and the technical defects of slow heating speed, large temperature difference and high energy consumption of the battery are solved.

Description

Technical Field

[0001] This invention relates to the field of thermal management technology for new energy batteries, and in particular to an endogenous self-heating electrode adapted to multi-system solid-state batteries. Background Technology

[0002] Solid-state batteries are considered the core direction of the next generation of energy storage devices: their use of non-flammable solid electrolytes avoids the safety risks of leakage and combustion of traditional liquid electrolytes from the root, and their theoretical energy density can be increased by 70% compared with traditional lithium-ion batteries. They are regarded by global research institutions and leading companies as the core technology route for power batteries and large-scale energy storage scenarios.

[0003] However, existing solid-state battery technology still faces significant application bottlenecks: First, the ion conductivity of solid electrolytes exhibits significant temperature sensitivity: the ion conductivity of most solid electrolytes at 25℃ (room temperature) is 2-5 orders of magnitude lower than that of traditional liquid electrolytes; if the ambient temperature decreases further, the battery's internal resistance increases sharply, and the discharge capacity directly decreases to less than 50% of the theoretical value, making it difficult to support the power supply needs of practical scenarios. Second, solid-state batteries using different technologies show significant differences in interface compatibility: while oxide solid electrolytes have excellent stability, they are hard and brittle, making it difficult to bond the electrode to the electrolyte interface. During charging and discharging, stress changes can easily generate interfacial voids, further increasing interfacial impedance; sulfide solid electrolytes have excellent ion conductivity, but are more sensitive to interfacial stress, easily generating microcracks during cycling, exacerbating capacity decay; polymer solid electrolytes are softer and more processable, but have poor high-temperature resistance, easily experiencing structural degradation and direct failure above 60℃. Currently, there is no universal technical solution in the industry that can simultaneously meet the thermal management requirements of these three mainstream solid-state battery types.

[0004] To address the low-temperature performance bottleneck of solid-state batteries, existing technical solutions mainly fall into two categories: first, developing novel low-temperature solid-state electrolyte systems; and second, external heating solutions. The development of new materials presents extremely high technical barriers and requires simultaneous verification of multiple indicators, including electrochemical compatibility, cycle stability, and scalable processing performance. The overall R&D cycle can take several years, making it difficult to support the rapid industrial deployment needs. Existing external heating solutions, whether for casing heating or environmental heating, suffer from unavoidable technical drawbacks: First, low heating efficiency and high energy consumption: heat must be conducted sequentially through the battery casing and the internal structure of the cell to the electrolyte layer, resulting in significant heat loss during the process, typically requiring more than 5 minutes to heat the battery to the target operating temperature. Second, poor temperature uniformity: large-capacity batteries (e.g., >100Ah) exhibit significant radial / axial temperature differences, easily leading to uneven local electrolyte and interface stress, accelerating battery performance degradation. Finally, external heating systems require additional components such as heat sinks and high-power switches, increasing the overall size and weight of the battery system and reducing its energy density, making it difficult to meet the application requirements of mainstream scenarios such as new energy vehicles and large-scale energy storage power stations.

[0005] In recent years, several built-in heating technologies have emerged in the industry, but they also have many limitations. For example, some solutions use a heating film added to the outside of the battery cell, with the area of ​​the heating film not less than the large surface area of ​​the battery cell. While this improves the heating speed, it still suffers from poor heating uniformity and occupies effective space inside the module, reducing the system's energy density. Other solutions use a short-circuit self-heating method, connecting a thin metal sheet to the positive electrode tab to generate a large amount of heat through an instantaneous short circuit. However, the heating process of this type of solution lacks controllability, and the current cannot be precisely adjusted. A large current in a short period of time may cause a sudden increase in local temperature, triggering a series of problems such as electrolyte thermal decomposition and rapid lithium dendrite growth. This poses several risks, severely impacting battery cycle life and safety. Some solutions incorporate heating elements within the cell, which improves heating uniformity to some extent, but require additional heating circuitry and temperature sensors. These sensors, typically located on the battery surface, cannot accurately measure the actual internal temperature, hindering precise temperature control. More importantly, the heating circuit and main discharge circuit in these solutions lack reliable electrical isolation, creating serious safety hazards. Furthermore, existing built-in heating designs are mostly only compatible with specific types of solid-state batteries, failing to simultaneously cover the three mainstream technologies of polymer, sulfide, and oxide batteries, thus hindering the industry's standardization needs.

[0006] Therefore, developing an internal heating electrode structure that can rapidly generate heat and precisely control temperature inside the battery, with excellent heating uniformity and strong interface adaptability, and can be adapted to the three mainstream solid-state battery technologies of polymer, sulfide, and oxide, is a key technological bottleneck that the current solid-state battery industry urgently needs to overcome. Summary of the Invention

[0007] This invention provides an internally self-heating electrode that is compatible with multi-system solid-state batteries, in order to solve one or more technical problems encountered in the prior art.

[0008] In a first aspect, the present invention provides an internally self-heating electrode suitable for multi-system solid-state batteries, applicable to polymer, sulfide, or oxide solid-state batteries. It comprises, from bottom to top, an electrode layer, an insulating support substrate layer, an electrothermal layer, a conductive circuit layer, a sealing and isolation protective layer, and the electrode layer itself. The electrothermal layer is disposed on the insulating support substrate layer, and the conductive circuit layer is disposed on both sides of the electrothermal layer and electrically connected to it. The sealing and isolation protective layer encapsulates the insulating support substrate layer, the electrothermal layer, and the conductive circuit layer to form an integrated independent heating circuit. The conductive circuit layer is used to connect to an external power source. Electrode layers are disposed on the outer sides of both the insulating support substrate layer and the sealing and isolation protective layer. The electrode layers are in contact with the electrolyte inside the polymer, sulfide, or oxide solid-state battery to form an energy storage output circuit. The independent heating circuit integrated inside the electrode and the energy storage output circuit are electrically isolated from each other through the sealing and isolation protective layer.

[0009] In a preferred embodiment, the electrode has a built-in self-heating structure that can stably maintain the solid-state battery's exclusive constant temperature range, thereby improving the ion conduction efficiency of the solid electrolyte and enhancing the tightness of the solid-solid interface.

[0010] In a preferred embodiment, when the electrodes are assembled inside the polymer solid-state battery, the cell system isothermal control range is set to 50°C to 70°C.

[0011] In a preferred embodiment, when used in a polymer solid-state battery, the constant-temperature heating inside the solid-state battery is used to activate the molecular chain movement of the polymer electrolyte and improve the ionic conductivity.

[0012] In a preferred embodiment, when used in a sulfide solid-state battery, constant temperature control reduces the grain boundary transport impedance of the solid electrolyte.

[0013] In a preferred embodiment, when used in an oxide solid-state battery, the thermal expansion effect is used to reduce the gap at the electrode-electrolyte interface.

[0014] In a preferred embodiment, the electrode heating power is adaptively adjusted according to the solid-state battery capacity and cell volume.

[0015] In a preferred embodiment, the overall structure of the electrode is adapted to the packaging and assembly process of a lithium metal anode solid-state battery.

[0016] In a preferred embodiment, the endogenous self-heating electrode is used to rapidly heat the solid-state battery from a low-temperature dormant state to its rated operating temperature.

[0017] One of the above technical solutions has the following advantages or beneficial effects: This invention integrates an independent heating circuit directly within the electrode, achieving native heat conduction from within the cell and completely eliminating the heat conduction bottleneck of traditional external heating solutions. During heating, heat is conducted directly from within the cell to the electrolyte layer, without needing to pass through external structures such as the casing. This reduces energy loss during heat transfer and shortens heating time. Combined with precise temperature control logic, it can heat the solid-state battery from a -40°C environment to its rated operating temperature range within 3 minutes, with heating energy consumption accounting for only 3.5% of the total battery energy, far lower than the energy consumption level of existing external heating solutions.

[0018] This invention achieves complete electrical isolation between the heating circuit and the energy storage output circuit through a sealed and protective layer, avoiding mutual interference between the heating circuit and the main discharge circuit, and significantly improving the safety of battery use. Simultaneously, the built-in heating structure eliminates the need for additional external space in the battery module, effectively reducing the volume redundancy of the thermal management system and optimizing the energy density performance of the battery system.

[0019] The electrode structure of this invention can be adapted to the thermal management requirements of three mainstream solid-state battery systems: it can precisely control the heating temperature within the optimal operating range of different systems. For polymer solid-state batteries, the temperature can be stabilized within the range of 50°C to 60°C, which can both activate the molecular chain movement of the polymer electrolyte to improve ionic conductivity and not exceed the upper limit threshold of its high-temperature degradation. For sulfide solid-state batteries, the constant temperature environment can effectively reduce the electrolyte grain boundary transport impedance and suppress the propagation of microcracks during cycling. For oxide solid-state batteries, the appropriate thermal expansion effect can reduce the interfacial gap between the electrode and the electrolyte and improve the interfacial adhesion.

[0020] The electrode structure of this invention enables flexible adjustment of heating power and can adaptively match parameters such as the actual capacity and cell volume of the battery. It eliminates the need for additional complex heating circuits, thereby reducing the hardware and algorithm complexity of the battery management system and improving the accuracy of heating control.

[0021] This invention adopts an integrated design with a built-in heating circuit, and its structure can be directly adapted to the packaging and assembly process of existing lithium metal anode solid-state batteries. It will not cause significant changes to the existing cell assembly process, which facilitates large-scale production and rapid industrialization.

[0022] The above overview is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features of the invention will become readily apparent from the accompanying drawings and the following detailed description. Attached Figure Description

[0023] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in the invention and should not be construed as limiting the scope of the invention.

[0024] Figure 1 This is a cross-sectional schematic diagram of the overall structure of the endogenous self-heating electrode sheet adapted to multi-system solid-state batteries in this embodiment. Detailed Implementation

[0025] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the invention. Therefore, the drawings and description are considered to be exemplary in nature and not restrictive.

[0026] This embodiment provides an internally self-heating electrode suitable for multi-system solid-state batteries, applicable to polymer, sulfide, or oxide solid-state batteries. See [link / reference]. Figure 1 As shown, the internally self-heating electrode includes, from bottom to top, an electrode layer 100, an insulating support substrate layer 110, an electric heating layer 120, a conductive circuit layer 130, a sealing and isolation protective layer 140, and the electrode layer 100. The electric heating layer 120 is disposed on the insulating support substrate layer 110, and the conductive circuit layer 130 is disposed on both sides of the electric heating layer 120 and electrically connected to the electric heating layer 120. The sealing and isolation protective layer 140 is used to encapsulate the insulating support substrate layer 110, the electric heating layer 120, and the conductive circuit layer 130 to form an integrated independent heating circuit. The conductive circuit layer 130 is used to connect to an external power source. Electrode layers 100 are disposed on the outer sides of both the insulating support substrate layer 110 and the sealing and isolation protective layer 140. The electrode layers 100 are in contact with the electrolyte 200 inside the polymer, sulfide, or oxide solid-state battery to form an energy storage output circuit. The independent heating circuit integrated inside the electrode and the energy storage output circuit are electrically isolated from each other through the sealing and isolation protective layer 140.

[0027] In a preferred embodiment, the electrode has a built-in self-heating structure that can stably maintain the solid-state battery's exclusive constant temperature range, thereby improving the ion conduction efficiency of the solid electrolyte and enhancing the tightness of the solid-solid interface.

[0028] In a preferred embodiment, when the electrodes are assembled inside the polymer solid-state battery, the cell system isothermal control range is set to 50°C to 70°C.

[0029] In a preferred embodiment, when used in a polymer solid-state battery, the constant-temperature heating inside the solid-state battery is used to activate the molecular chain movement of the polymer electrolyte and improve the ionic conductivity.

[0030] In a preferred embodiment, when used in a sulfide solid-state battery, constant temperature control reduces the grain boundary transport impedance of the solid electrolyte.

[0031] In a preferred embodiment, when used in an oxide solid-state battery, the thermal expansion effect is used to reduce the gap at the electrode-electrolyte interface.

[0032] In a preferred embodiment, the electrode heating power is adaptively adjusted according to the solid-state battery capacity and cell volume.

[0033] In a preferred embodiment, the overall structure of the electrode is adapted to the packaging and assembly process of a lithium metal anode solid-state battery.

[0034] In a preferred embodiment, the endogenous self-heating electrode is used to rapidly heat the solid-state battery from a low-temperature dormant state to its rated operating temperature. Example 1

[0035] This embodiment provides an internally heated electrode suitable for multi-system solid-state batteries, the structure of which is as follows: Figure 1 As shown, the battery specifically includes, from bottom to top, an electrode layer 100, an insulating support substrate layer 110, an electric heating layer 120, a conductive circuit layer 130, a sealing and isolation protective layer 140, and an electrode layer 100. The electric heating layer 120 is disposed on the insulating support substrate layer 110, and the conductive circuit layer 130 is disposed on both sides of the electric heating layer 120 and electrically connected to the electric heating layer 120. The sealing and isolation protective layer 140 is used to encapsulate the insulating support substrate layer 110, the electric heating layer 120, and the conductive circuit layer 130 to form an integrated independent heating circuit. The conductive circuit layer 130 is used to connect an external controllable DC power supply. Electrode layers 100 are disposed on both sides of the sealing and isolation protective layer 140, and the electrode layers 100 are in contact with the electrolyte inside the polymer, sulfide, or oxide solid-state battery to form an energy storage output circuit. The independent heating circuit integrated inside the electrode and the energy storage output circuit are electrically isolated from each other through the sealing and isolation protective layer 140. The two circuits are completely independent in structure and have no direct electrical contact, thus completely avoiding the risk of interference between the heating circuit and the energy storage circuit.

[0036] The electrode layer 100 uses a positive or negative electrode material that matches the corresponding solid-state battery system, and the surface flatness of the electrode layer 100 must be strictly controlled within the process requirements to ensure sufficient contact with the solid electrolyte. The insulating support substrate layer 110 uses a high-strength, high-insulation, and heat-resistant polyimide (PI) film material, the thickness of which can be adjusted according to the actual cell design requirements. This ensures both structural support for the heating layer 120 and the conductive circuit layer 130, and reliable electrical insulation between the heating layer 120 and the underlying electrode layer 100. The heating layer 120 uses a metal heating material with stable resistivity and excellent corrosion resistance, such as iron-chromium-aluminum alloy or nickel-chromium alloy, and can be formed into a uniform shape through sputtering, coating, or photolithography processes. The thin film layer ensures the uniformity of the heating power density; the conductive circuit layer 130 is made of a metal material with excellent conductivity and strong anti-migration properties, such as silver-palladium alloy or copper-palladium alloy, and is formed by printing or electroplating processes. Its line width, line spacing and thickness can be flexibly adjusted according to the heating power requirements; the sealing and isolation protective layer 140 is made of a ceramic composite resin material with high insulation performance, high thermal conductivity and excellent bonding strength. It needs to ensure that it will not peel or crack during long-term use, and also needs to have excellent thermal conductivity to ensure that the heat generated by the electric heating layer 120 can be evenly conducted to the electrode layers 100 on both sides; at the same time, the material of the sealing and isolation protective layer 140 needs to have good chemical compatibility with solid electrolytes of different systems and will not react with any chemicals. Example 2

[0037] This embodiment provides an internally self-heating electrode that is compatible with multiple solid-state battery systems. The only difference between this embodiment and Embodiment 1 is that the electrode has a built-in self-heating structure that can stably maintain the exclusive constant temperature range of the solid-state battery, thereby improving the ion conduction efficiency of the solid electrolyte and enhancing the tightness of the solid-solid interface.

[0038] Specifically, the power density of the electric heating layer 120 is precisely matched with the thermal conductivity of the sealing and isolation protective layer 140. This, combined with an external temperature sensor and control module, ensures that the battery operating temperature is stably maintained within a preset range. The temperature sensor is located inside the cell near the electrolyte layer, allowing for real-time acquisition of actual temperature data within the cell, which is then transmitted to the external control module. The control module precisely controls the heat generation of the electric heating layer 120 by adjusting the input current of the conductive circuit layer 130. This satisfies the constant temperature requirements of different solid-state battery systems while preventing battery performance degradation due to overheating.

[0039] The remaining undescribed technical features are completely consistent with those in Example 1 and will not be repeated here. Example 3

[0040] This embodiment provides an internally self-heating electrode that is compatible with multiple solid-state battery systems. The only difference between this embodiment and Embodiment 2 is that when the electrode is assembled inside the polymer solid-state battery, the constant temperature control range of the cell system is set to 50°C to 60°C.

[0041] Specifically, polymer solid electrolytes are extremely sensitive to temperature: below 50°C, the movement of polymer chains within the electrolyte is frozen, ion mobility decreases significantly, and ionic conductivity is insufficient to support high-rate discharge requirements; above 60°C, the polymer chains of the electrolyte undergo thermal deformation, leading to a decrease in the electrolyte's mechanical strength and even the risk of thermal runaway due to localized short circuits. Based on this characteristic, this embodiment sets the lower limit of the constant temperature control range to 50°C and the upper limit to 60°C; during the heating process, when the temperature reaches the intermediate value of 55°C, the control module reduces the heating power to 30% of the normal power to reduce temperature fluctuations and ensure that the temperature difference inside the cell does not exceed ±2°C; simultaneously, the sealing and protective layer 140 uses a material with better thermal compatibility with the polymer solid electrolyte, ensuring thermal conductivity while avoiding localized thermal stress impacts on the polymer electrolyte.

[0042] The remaining undescribed technical features are completely consistent with those in Example 2 and will not be repeated here. Example 4

[0043] This embodiment provides an internally self-heating electrode that is compatible with multiple solid-state battery systems. The only difference between this embodiment and Embodiment 2 is that the polymer electrolyte molecular chain movement is activated by constant-temperature heating inside the solid-state battery, thereby improving the ionic conductivity of the polymer electrolyte.

[0044] Specifically, the ion conductivity of polymer solid electrolytes is highly dependent on the movement of internal polymer chain segments: at low temperatures, the chain segment movement is frozen, resulting in extremely low ion mobility; by precisely and stably controlling the temperature within the range of 50℃ to 60℃, the movement of polymer chain segments inside the electrolyte can be activated, providing more transport channels for lithium ion migration and significantly improving the ion conductivity of the polymer electrolyte; at the same time, the constant temperature environment can make the stress distribution inside the polymer electrolyte more uniform, avoiding damage to the electrolyte structure caused by temperature fluctuations and ensuring the long-term stability of ion conductivity.

[0045] The remaining undescribed technical features are completely consistent with those in Example 2 and will not be repeated here. Example 5

[0046] This embodiment provides an internally self-heating electrode that is compatible with multiple solid-state batteries. The only difference between this embodiment and Embodiment 2 is that when assembled into a sulfide solid-state battery, the internal constant temperature control reduces the grain boundary transport impedance of the sulfide solid electrolyte.

[0047] Specifically, sulfide solid electrolytes exhibit excellent ionic conductivity, but grain boundary transport impedance is a key bottleneck restricting their performance: at low temperatures, the activation energy for ion migration at the electrolyte grain boundaries increases significantly, leading to a substantial increase in impedance; simultaneously, sulfide electrolytes are highly sensitive to temperature changes, and uneven temperature distribution can cause grain boundary stress concentration, generating microcracks and further deteriorating grain boundary transport performance. The built-in heating structure in this embodiment can create a uniform temperature field in the electrolyte layer, strictly controlling the internal operating temperature difference of the cell within ±2℃, avoiding increased grain boundary impedance due to excessively low local temperatures; furthermore, a constant temperature environment can stabilize the grain boundary structure within the sulfide electrolyte, suppressing the propagation of microcracks during cycling and reducing grain boundary transport impedance.

[0048] The remaining undescribed technical features are completely consistent with those in Example 2 and will not be repeated here. Example 6

[0049] This embodiment provides an endogenous self-heating electrode that is compatible with multi-system solid-state batteries. The only difference between this embodiment and Embodiment 2 is that when assembled into an oxide solid-state battery, the interfacial gap between the electrode and the oxide solid-state electrolyte is reduced by the thermal expansion effect.

[0050] Specifically, oxide solid electrolytes have high mechanical strength, but are hard and brittle. The interfacial adhesion between the electrode and the electrolyte is the core factor limiting performance: during charge-discharge cycles, the electrode and electrolyte undergo minute volume changes, resulting in local voids at the interface and increasing interfacial impedance. In severe cases, current concentration can occur at these voids, triggering lithium dendrite growth and posing safety hazards. Uniform heating through a built-in heating structure can utilize the moderate thermal expansion effect between the electrode and the oxide solid electrolyte to fill these tiny voids at the interface, increasing the interfacial contact area and reducing interfacial impedance. Simultaneously, uniform heating ensures a more even distribution of thermal expansion stress at the interface, preventing electrolyte layer cracking or electrode layer peeling caused by excessive local stress.

[0051] The remaining undescribed technical features are completely consistent with those in Example 2 and will not be repeated here. Example 7

[0052] This embodiment provides an internally self-heating electrode that is compatible with multiple solid-state battery systems. The only difference between this embodiment and Embodiment 1 is that the electrode heating power is adaptively matched and adjusted according to the solid-state battery capacity and cell volume.

[0053] Specifically, the design power of the electric heating layer 120 is precisely calculated based on the battery's actual capacity, cell volume, thermal conductivity and specific heat capacity parameters of the solid electrolyte system, and the target heating rate requirement. During actual heating, the control module dynamically adjusts the heating power according to the real-time temperature inside the cell, the ambient temperature, and the battery's charging and discharging state. For example, when the battery temperature is low and a rapid temperature increase is needed, the control module adjusts the heating power to the rated power to raise the internal temperature of the cell as quickly as possible. When the battery temperature approaches the preset range, the control module gradually reduces the heating power to stabilize the temperature within the target range. Furthermore, the heating power adjustment logic prioritizes matching the battery's actual operating conditions: during charging and discharging, the heating power prioritizes maintaining the internal operating temperature of the cell; during static conditions, the heating power prioritizes compensating for ambient temperature loss, keeping temperature fluctuations within a minimal range.

[0054] The remaining undescribed technical features are completely consistent with those in Example 1 and will not be repeated here. Example 8

[0055] This embodiment provides an internally self-heating electrode that is compatible with multi-system solid-state batteries. The only difference between this embodiment and Embodiment 1 is that the overall structure of this electrode is adapted to the packaging and assembly process of lithium metal anode solid-state batteries.

[0056] Specifically, the overall thickness, length, width, and dimensions of the electrode, as well as the material, areal density, and porosity of the electrode layer 100, are all matched with the assembly process parameters of existing lithium metal anode solid-state batteries. The heating circuit lead-out line inside the electrode is located at the side edge of the electrode, which will not affect the stacking and winding assembly process of the battery cell. At the same time, the outer surface of the sealing and isolation protective layer 140 is specially roughened to ensure the adhesion strength with the solid electrolyte layer and avoid defects such as interlayer peeling and bubbles that occur during the assembly process. In addition, the structural design of the electrode fully considers the expansion stress characteristics of the lithium metal anode. Its structural strength and toughness can withstand the volume changes of the lithium metal anode during repeated charging and discharging without deformation or damage. There is no need to make significant adjustments to the existing battery cell assembly process, which is conducive to mass production.

[0057] The remaining undescribed technical features are completely consistent with those in Example 1 and will not be repeated here. Example 9

[0058] This embodiment provides an endogenous self-heating electrode that is compatible with multiple solid-state battery systems. The only difference between this embodiment and Embodiment 1 is that the endogenous self-heating electrode is used to rapidly heat the solid-state battery from a low-temperature dormant state to its rated operating temperature.

[0059] Specifically, when the solid-state battery is in a low-temperature dormant state (ambient temperature below 0°C), the battery management system first activates the built-in heating circuit. Through the uniform and rapid heating of the electric heating layer 120, the internal temperature of the cell is quickly raised to the rated operating temperature range. During the heating process, the independent heating circuit and the energy storage output circuit are completely electrically isolated. After the temperature stabilizes, the heating circuit automatically switches to a low-power heat preservation state, and the energy storage output circuit then begins normal charging and discharging. The built-in heating structure has an extremely fast thermal response speed, which can rapidly raise the solid-state battery from a low temperature environment of -40°C to the rated operating temperature range within 3 minutes. The heating rate is significantly higher than that of traditional external heating solutions, and the heating energy consumption of the entire process accounts for only 3.5% of the total battery energy, which will not have a significant impact on the battery's usable energy.

[0060] The remaining undescribed technical features are completely consistent with those in Example 1 and will not be repeated here.

[0061] In the description of this specification, 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. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0062] 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 technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0063] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in the present invention, and these should all be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An internally heated electrode suitable for multi-system solid-state batteries, applicable to polymer, sulfide, or oxide solid-state batteries, characterized in that, The battery comprises, from bottom to top, an electrode layer, an insulating support substrate layer, an electric heating layer, a conductive circuit layer, a sealing and isolation protective layer, and an electrode layer. The electric heating layer is disposed on the insulating support substrate layer, and the conductive circuit layer is disposed on both sides of the electric heating layer and electrically connected to it. The sealing and isolation protective layer is used to encapsulate the insulating support substrate layer, the electric heating layer, and the conductive circuit layer to form an integrated independent heating circuit. The conductive circuit layer is used to connect to an external power source. Electrode layers are disposed on the outer sides of both the insulating support substrate layer and the sealing and isolation protective layer. The electrode layers are in contact with the electrolyte inside the polymer, sulfide, or oxide solid-state battery to form an energy storage output circuit. The independent heating circuit integrated inside the electrode and the energy storage output circuit are electrically isolated from each other through the sealing and isolation protective layer.

2. The endogenous self-heating electrode according to claim 1, characterized in that, The electrode has a built-in self-heating structure that can stably maintain the exclusive constant temperature range of the solid-state battery, thereby improving the ion conduction efficiency of the solid electrolyte and enhancing the tightness of the solid-solid interface.

3. The endogenous self-heating electrode according to claim 1, characterized in that, When the electrodes are assembled inside the polymer solid-state battery, the constant temperature control range of the cell system is set to 50℃~70℃.

4. The endogenous self-heating electrode according to claim 1, characterized in that, When used in polymer solid-state batteries, the constant-temperature heating inside the solid-state battery is used to activate the molecular chain movement of the polymer electrolyte and improve ionic conductivity.

5. The endogenous self-heating electrode according to claim 1, characterized in that, When used in sulfide solid-state batteries, constant temperature control reduces the grain boundary transport impedance of the solid electrolyte.

6. The endogenous self-heating electrode according to claim 1, characterized in that, When used in oxide solid-state batteries, the thermal expansion effect is used to reduce the gap between the electrode and the electrolyte interface.

7. The endogenous self-heating electrode according to claim 1, characterized in that, The electrode heating power is adaptively adjusted based on the solid-state battery capacity and cell volume.

8. The endogenous self-heating electrode according to claim 1, characterized in that, The overall structure of this electrode is adapted to the packaging and assembly process of lithium metal anode solid-state batteries.

9. The endogenous self-heating electrode according to claim 1, characterized in that, The internally heated electrode is used to rapidly heat the solid-state battery from a low-temperature dormant state to its rated operating temperature.

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