A high-density energy storage pulse capacitor

Abstract

The application discloses a high-density energy storage pulse capacitor, and belongs to the technical field of electric energy storage devices. The capacitor comprises a shell, positive and negative electrode leads and a capacitor core sealed in the shell. The capacitor core comprises a first outer insulation packaging layer, a first electrode unit, a solid-state electrolyte layer, a second electrode unit and a second outer insulation packaging layer arranged in sequence from top to bottom. The two electrode units are both composed of metal conductive three-dimensional frameworks and high-thermal-conductivity ceramic three-dimensional frameworks which are interwoven and in contact, forming a three-dimensionally connected inner pore network. The solid-state electrolyte layer is located between the two electrode units and fills the inner pore network. The application can improve the heat dissipation bottleneck, the contradiction between energy and power and the high-voltage insulation problem of the traditional pulse capacitor under high-power working, and can realize high energy density, high power density, high reliability and excellent heat dissipation capacity.

Description

Technical Field

[0001] This invention relates to energy storage devices, and more specifically to a high-density energy storage pulse capacitor. Background Technology

[0002] Pulse capacitors are core energy storage components in pulsed power systems such as electromagnetic emission, lasers, and particle accelerators, and their performance directly determines the system's output power and efficiency.

[0003] Traditional pulse capacitors face the following problems when pursuing high energy density and high power density: Under high-current pulse operation, ohmic heat (Joule heat) is generated rapidly. The electron conduction and heat dissipation of traditional electrodes rely on a single material (such as a metal current collector or carbon material), resulting in a high degree of overlap between the heat flow and current path. Heat easily accumulates inside the electrode, causing localized overheating. This accelerates electrolyte decomposition and electrode material aging, severely limiting the device's operating frequency, lifespan, and reliability. Summary of the Invention

[0004] This invention provides a high-density energy storage pulse capacitor to overcome the above-mentioned problems.

[0005] To address the aforementioned problems, this invention discloses a high-density energy storage pulse capacitor, comprising a shell, a positive electrode lead, a negative electrode lead, and a capacitor core sealed within the shell. The capacitor core includes, from top to bottom, a first outer insulating encapsulation layer, a first electrode unit, a solid electrolyte layer, a second electrode unit, and a second outer insulating encapsulation layer. Both the first and second electrode units comprise interwoven and penetrating metal conductive three-dimensional skeletons and high thermal conductivity ceramic three-dimensional skeletons, with the metal conductive three-dimensional skeleton and the high thermal conductivity ceramic three-dimensional skeleton in contact to form a three-dimensional interconnected internal porous network. The positive electrode lead is electrically connected to the metal conductive three-dimensional skeleton in the first electrode unit, and the negative electrode lead is electrically connected to the metal conductive three-dimensional skeleton in the second electrode unit. The solid electrolyte layer is disposed between the first and second electrode units and fills the internal porous network of both the first and second electrode units.

[0006] In one embodiment of the present invention, the material of the high thermal conductivity ceramic three-dimensional skeleton is boron nitride ceramic body or alumina ceramic body.

[0007] In one embodiment of the present invention, the metal conductive three-dimensional framework is a continuous metal layer deposited on the surface of a high thermal conductivity ceramic three-dimensional framework by chemical vapor deposition or electroplating process, and the metal layers are interconnected on the network surface formed by the high thermal conductivity ceramic three-dimensional framework.

[0008] In one embodiment of the present invention, the internal pore network in the first electrode unit and the second electrode unit is gradient distributed; wherein, in the internal pore network, the average pore diameter of the region near the solid electrolyte layer is smaller than the average pore diameter of the region far from the solid electrolyte layer; and the porosity of the region near the solid electrolyte layer is lower than the porosity of the region far from the solid electrolyte layer.

[0009] In one embodiment of the present invention, sheet-like high thermal conductivity fillers are three-dimensionally dispersed in the substrate of the first outer insulating encapsulation layer and the second outer insulating encapsulation layer, and the sheet-like high thermal conductivity fillers are in-plane oriented and overlap each other inside the substrate; the sheet-like high thermal conductivity fillers are connected to the high thermal conductivity ceramic three-dimensional skeleton in the outer surface of the first electrode unit and the second electrode unit.

[0010] In one embodiment of the present invention, the base material of the first outer insulating encapsulation layer and the second outer insulating encapsulation layer is a polymer; piezoelectric ceramic particles are also dispersed in the first outer insulating encapsulation layer and the second outer insulating encapsulation layer, and the surface of the piezoelectric ceramic particles is modified by a silane coupling agent.

[0011] In one embodiment of the present invention, the solid electrolyte is formed by wetting an ionic liquid with a cross-linked polymer network, wherein crown ethers or cyclodextrins are bonded in the cross-linked polymer network, and the crown ethers or cyclodextrins can reversibly coordinate cations in the ionic liquid.

[0012] In one embodiment of the present invention, the coordination strength of crown ethers or cyclodextrins to cations decreases with increasing temperature.

[0013] In one embodiment of the present invention, a temperature-sensitive element is further included; at least one thermally conductive branch extends from the high thermal conductivity ceramic three-dimensional skeleton in the first electrode unit, and the thermally conductive branch is directly thermally coupled to the thermistor portion of the temperature-sensitive element; the electrically triggered portion of the temperature-sensitive element is connected in series in the current path formed by the positive electrode lead and the metal conductive three-dimensional skeleton; or, at least one thermally conductive branch extends from the high thermal conductivity ceramic three-dimensional skeleton in the second electrode unit, and the thermally conductive branch is directly thermally coupled to the thermistor portion of the temperature-sensitive element; the electrically triggered portion of the temperature-sensitive element is connected in series in the current path formed by the corresponding negative electrode lead and the metal conductive three-dimensional skeleton; wherein, when the local temperature of the electrode unit is transferred to the temperature-sensitive element through the high thermal conductivity ceramic three-dimensional skeleton and the thermally conductive branch and reaches its operating temperature threshold, the electrically triggered portion is disconnected.

[0014] In one embodiment of the present invention, the operating temperature threshold of the temperature-sensitive element is higher than the rated operating temperature of the capacitor and lower than the thermal decomposition initiation temperature of the solid electrolyte.

[0015] This invention has the following advantages:

[0016] This invention discloses a high-density energy storage pulse capacitor, which includes a shell, positive and negative leads, and a capacitor core sealed within the shell. The capacitor core comprises, from top to bottom, a first outer insulating encapsulation layer, a first electrode unit, a solid electrolyte layer, a second electrode unit, and a second outer insulating encapsulation layer. Both electrode units are composed of an interwoven and contacting three-dimensional conductive metal framework and a high thermal conductivity ceramic framework, forming a three-dimensional interconnected internal porous network. The interwoven and directly contacting three-dimensional conductive metal framework and the high thermal conductivity ceramic framework decouple and couple the current transmission path and heat diffusion path in three-dimensional space. During charging and discharging, the Joule heat generated by the conductive metal framework is instantly transferred from the metal framework to the ceramic framework via the contact interface, using the shortest path, and rapidly and uniformly diffuses along its three-dimensional network, preventing heat accumulation and the formation of high-temperature hotspots. This efficient heat dissipation mechanism enables the capacitor to withstand extremely high pulse repetition frequencies, greatly extending its cycle life.

[0017] In this invention, a three-dimensional continuous metal skeleton running through the entire electrode provides an ultra-low resistance, high-speed transmission path for electrons, ensuring that stored charge can be rapidly extracted in a very short time, releasing an instantaneous ultra-large current and meeting the stringent requirements of high power density. The first and second outer insulating encapsulation layers can effectively reduce the actual electric field strength experienced by the solid electrolyte layer and electrode interface. At the same time, they can smooth the electric field at the electrode edge, eliminating field distortion points that may lead to partial discharge or breakdown, enabling the capacitor to operate stably at higher voltages.

[0018] This invention significantly improves electron transport efficiency and thermal diffusion efficiency, effectively avoids local overheating, and synergistically enhances the power density, cycle life, and operational reliability of capacitors, making it suitable for high-voltage, high-current pulse power systems. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0020] Figure 1 This is a schematic diagram of the structure of the high-density energy storage pulse capacitor according to an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram of the structure of the metal conductive three-dimensional skeleton and the high thermal conductivity ceramic three-dimensional skeleton in the embodiments of the present invention.

[0022] Figure 3 This is a schematic diagram of the substrate of the first outer insulating encapsulation layer in an embodiment of the present invention;

[0023] Figure 4 This is a schematic diagram of the structure of a high-density energy storage pulse capacitor with a temperature-sensitive element according to an embodiment of the present invention;

[0024] Explanation of reference numerals in the attached figures:

[0025] 101-Outer casing, 201-Positive lead, 301-Negative lead, 401-Capacitor core, 41-First outer insulating encapsulation layer, 42-First electrode unit, 43-Solid electrolyte layer, 44-Second electrode unit, 45-Second outer insulating encapsulation layer; 51-Metal conductive three-dimensional skeleton, 52-High thermal conductivity ceramic three-dimensional skeleton, 521-Heat-conducting branch; 61-Sheet-shaped high thermal conductivity filler, 62-Piezoelectric ceramic particles; 71-Temperature-sensitive element, 710-Thermistor part, 711-Electrically triggered part. Detailed Implementation

[0026] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings.

[0027] This invention provides a high-density energy storage pulse capacitor, referenced... Figure 1 The capacitor core 401 includes a housing 101, a positive electrode lead 201, a negative electrode lead 301, and a capacitor core 401 sealed within the housing 101. The capacitor core 401 includes, from top to bottom, a first outer insulating encapsulation layer 41, a first electrode unit 42, a solid electrolyte layer 43, a second electrode unit 44, and a second outer insulating encapsulation layer 45. The first electrode unit 42 and the second electrode unit 44 each include interwoven and penetrating metal conductive three-dimensional skeleton 51 and high thermal conductivity ceramic three-dimensional skeleton 52, and the metal conductive three-dimensional skeleton 51 and the high thermal conductivity ceramic three-dimensional skeleton 52 are in contact to form a three-dimensional interconnected internal porous network. The positive electrode lead 201 is electrically connected to the metal conductive three-dimensional skeleton 51 in the first electrode unit 42, and the negative electrode lead 301 is electrically connected to the metal conductive three-dimensional skeleton 51 in the second electrode unit 44. The solid electrolyte layer 43 is disposed between the first electrode unit 42 and the second electrode unit 44, and fills the internal porous network of the first electrode unit 42 and the internal porous network of the second electrode unit 44.

[0028] In this embodiment of the invention, the first electrode unit 42 and the second electrode unit 44 serve as the positive and negative electrodes of a capacitor, and their structures are identical or complementary and symmetrical. The positive electrode lead 201 is electrically connected to the metal conductive three-dimensional skeleton 51 in the first electrode unit 42; the negative electrode lead 301 is electrically connected to the metal conductive three-dimensional skeleton 51 in the second electrode unit 44.

[0029] refer to Figure 2Each electrode unit is composed of two interwoven and interconnected three-dimensional continuous frameworks. These two three-dimensional continuous frameworks are a metallic conductive three-dimensional framework 51 and a high thermal conductivity ceramic three-dimensional framework 52. The metallic conductive three-dimensional framework 51 is a three-dimensional network composed of high-conductivity metals (such as copper, aluminum, silver, or their alloys), and its core function is to provide a low-resistance, high-speed electron transport path. The high thermal conductivity ceramic three-dimensional framework 52 is a three-dimensional network composed of high thermal conductivity insulating ceramic materials (such as aluminum nitride, beryllium oxide, and silicon carbide), and its core function is to provide an efficient heat dissipation path. The metallic conductive three-dimensional framework 51 and the high thermal conductivity ceramic three-dimensional framework 52 are in direct contact in three-dimensional space, forming a composite body filled with a three-dimensional interconnected internal porous network. This internal porous network is formed by the gaps left after the interweaving of the metal and ceramic frameworks.

[0030] like Figure 1 As shown, the solid electrolyte layer 43 is located between the first electrode unit 42 and the second electrode unit 44. During the manufacturing process, the solid electrolyte material (such as a modified polymer electrolyte, an inorganic ceramic electrolyte, or a composite material thereof) not only forms this intermediate continuous layer, but also simultaneously fills and solidifies the three-dimensional interconnected internal porous network inside the first electrode unit 42 and the second electrode unit 44. This makes the solid electrolyte, microscopically, a continuous ionic conductor phase and a structural bonding phase that connects the two electrodes and solidifies part of the internal porous network of the first electrode unit 42 and the second electrode unit 44.

[0031] like Figure 1 As shown, the first outer insulating encapsulation layer 41 and the second outer insulating encapsulation layer 45 serve as the top and bottom layers of the capacitor core 401, respectively. They are made of insulating materials with high dielectric strength and high heat resistance (such as polyimide film, mica sheets, or special ceramic sheets). Their main functions are: to withstand the main voltage drop of the working voltage, to homogenize the electric field distribution inside the core, to prevent electric field distortion and surface discharge at the electrode edges, and to provide mechanical protection and encapsulation for the fragile internal composite electrode structure.

[0032] The working principle of the capacitor of this invention:

[0033] (1) Energy storage process: During charging, an external voltage is applied to the metal conductive three-dimensional skeleton 51 of the two electrode units through the positive and negative leads 301. This voltage is mainly borne by the two outer insulating encapsulation layers (i.e., the first outer insulating encapsulation layer 41 and the second outer insulating encapsulation layer 45) and the middle solid electrolyte layer 43. Under the drive of the electric field, ions in the solid electrolyte migrate and penetrate into the huge internal pore network inside the two electrode units (i.e., the first electrode unit 42 and the second electrode unit 44) through the continuous ion phase, and form an electric double layer or undergo a rapid surface redox reaction on the huge surface of the metal conductive three-dimensional skeleton 51, thereby efficiently storing electrical energy in the form of chemical potential energy.

[0034] (2) Pulse discharge process: During discharge, the external load is turned on. The charge stored at the interface between the electrode unit and the solid electrolyte layer is rapidly released, and electrons are rapidly collected to their respective electrode leads through the ultra-low resistance metal conductive three-dimensional skeleton 51 network, forming a huge current (pulse). At the same time, ions migrate in the opposite direction through the continuous channels composed of solid electrolyte to complete charge balance.

[0035] (3) Thermal management process: At the moment of charging and discharging, the large current flowing through the metal conductive three-dimensional skeleton 51 generates Joule heat. Since the high thermal conductivity ceramic three-dimensional skeleton 52 and the metal conductive three-dimensional skeleton 51 are in full contact in three-dimensional space, the heat can be directly transferred from the metal conductive three-dimensional skeleton 51, the heat source, to the high thermal conductivity ceramic three-dimensional skeleton 52 through the shortest path, and then rapidly diffused along the network of the high thermal conductivity ceramic three-dimensional skeleton 52 to the entire electrode volume, and finally dissipated through the outer shell 101. This achieves spatial separation and instantaneous response of heat generation and dissipation, avoiding local heat accumulation.

[0036] It is worth noting that the three-dimensional composite electrode structure of the first electrode unit 42 and the second electrode unit 44 breaks the limitation of traditional two-dimensional planar electrodes that couple electron transport and heat diffusion functions to the same material layer. That is, in this embodiment of the invention: the metal conductive three-dimensional skeleton 51 can be designed purely based on maximizing conductivity and specific surface area without considering thermal conductivity; the high thermal conductivity ceramic three-dimensional skeleton 52 can focus on optimizing thermal conductivity, and its insulation properties can avoid electric field distortion. The synergy between the outer insulating encapsulation layer and the internal energy storage unit significantly improves the overall breakdown voltage and eliminates the risk of internal partial discharge and surface flashover.

[0037] Furthermore, in this embodiment of the invention, the material of the high thermal conductivity ceramic three-dimensional framework 52 is either boron nitride ceramic or alumina ceramic. Boron nitride possesses excellent in-plane thermal conductivity among ceramic materials, enabling efficient heat transfer. Simultaneously, it exhibits excellent electrical insulation, preventing short circuits or electric field distortion within the electrodes. The layered structure of boron nitride is easily controlled through process manipulation to form pores, providing an ideal template carrier for the subsequent formation of the metal conductive three-dimensional framework 51, ensuring a stable interpenetrating network between the two frameworks. Alumina ceramic, on the other hand, has moderately high thermal conductivity, excellent electrical insulation, high mechanical hardness, and good chemical stability, maintaining structural and performance stability under complex operating conditions. Furthermore, alumina material has relatively low cost and a mature manufacturing process, facilitating large-scale production. Both materials can construct the high thermal conductivity ceramic three-dimensional framework 52, enabling rapid heat dissipation; their insulating properties effectively prevent short circuits or electric field distortion within the electrodes, ensuring the electrical safety of the capacitor.

[0038] Furthermore, in this embodiment of the invention, the metal conductive three-dimensional skeleton 51 is a continuous metal layer deposited on the surface of the high thermal conductivity ceramic three-dimensional skeleton 52 by chemical vapor deposition or electroplating process, and the metal layer is interconnected on the network surface formed by the high thermal conductivity ceramic three-dimensional skeleton 52.

[0039] Chemical vapor deposition (CVD) can achieve conformal and uniform metal coating within complex three-dimensional pores. The deposited metal layer has controllable thickness, high density, and strong adhesion to the inner surface of the ceramic skeleton, ensuring that the metal layer is not easily detached or peeled off during long-term charge-discharge cycles. Electroplating, which uses an electric field to drive the deposition of metal ions on the inner surface of the ceramic skeleton's pores, can also form a continuous conductive metal layer. This process has advantages such as high maturity, high production efficiency, and relatively low cost, making it suitable for mass production. In this embodiment, a continuous metal layer is deposited on the inner surface of the pores of the high thermal conductivity ceramic three-dimensional skeleton 52 using CVD or electroplating. This metal layer is interconnected within the pores of the high thermal conductivity ceramic three-dimensional skeleton 52, achieving close interfacial contact with it. This establishes an interface channel with extremely low thermal resistance, allowing the Joule heat generated by the conductive metal three-dimensional skeleton 51 to be instantly transferred to the ceramic skeleton and rapidly diffused. At the same time, this continuous metal layer ensures low-impedance electron transport required for high-power charging and discharging, and can also improve the power performance and thermal management capabilities of the capacitor.

[0040] In some embodiments of the present invention, such as Figure 2 As shown, the internal pore network in the first electrode unit 42 and the second electrode unit 44 exhibits a gradient distribution. Within this internal pore network, the average pore size in the region near the solid electrolyte layer 43 is smaller than the average pore size in the region far from the solid electrolyte layer 43; the porosity in the region near the solid electrolyte layer 43 is lower than the porosity in the region far from the solid electrolyte layer 43. In this embodiment, the gradient distribution of the internal pore network in the first electrode unit 42 and / or the second electrode unit 44 effectively suppresses side reactions and dendrite growth at the interface, improving interface stability and rate performance, while ensuring a high loading of active material on the electrode.

[0041] The internal pore network of the electrode unit is formed by the interweaving of a metallic conductive three-dimensional framework 51 and a high thermal conductivity ceramic three-dimensional framework 52. Its gradient distribution is achieved by controlling the interweaving morphology and spatial distribution of the two frameworks. The side closer to the solid electrolyte layer 43 has fine pores and low porosity; the side farther away has coarse pores and high porosity. The fine and low porosity near the interface provides a larger actual contact area, reduces local current density and interfacial impedance, and enhances mechanical bonding strength. The coarse and high porosity inside provides space for rapid ion transport in bulk and for accommodating more active materials.

[0042] In some embodiments of the present invention, the second outer insulating encapsulation layer 45 and the first outer insulating encapsulation layer 41 have essentially the same structure, as shown in the reference. Figure 3 In this embodiment, sheet-like high thermal conductivity fillers 61 are three-dimensionally dispersed in the substrate of the first outer insulating encapsulation layer 41 and the second outer insulating encapsulation layer 45. These sheet-like high thermal conductivity fillers 61 are oriented in-plane within the substrate and overlap each other. The sheet-like high thermal conductivity fillers 61 are connected to the high thermal conductivity ceramic three-dimensional framework 52 on the outer surface of the first electrode unit 42 and the second electrode unit 44. In this embodiment, the sheet-like high thermal conductivity fillers 61 can be boron nitride nanosheets or graphene sheets. Three-dimensional dispersion refers to the sheet-like high thermal conductivity fillers 61 being uniformly distributed throughout the entire volume of the insulating encapsulation layer, rather than just being surface-coated. The in-plane orientation and overlap of the sheet-like high thermal conductivity fillers 61 within the substrate can be achieved through processes such as casting, calendering, or electric field orientation, so that the planes of the sheet-like high thermal conductivity fillers 61 are arranged parallel to the surface of the insulating encapsulation layer, and adjacent sheet-like high thermal conductivity fillers 61 are in contact with each other to form a thermally conductive network. Since the thermal conductivity of the insulating encapsulation layer is significantly higher in the in-plane direction than in the thickness direction, this orientation design maximizes the heat transfer efficiency of the thermally conductive network. The thermally conductive network forms a close physical contact with the ends of the high thermal conductivity ceramic three-dimensional skeleton 52 extending from the electrode unit, creating a low thermal resistance heat transfer interface. In this way, heat from the metal conductive three-dimensional skeleton 51 can be rapidly conducted to the outer surface of the electrode unit through the high thermal conductivity ceramic three-dimensional skeleton 52. Then, this heat is captured by the sheet-like high thermal conductivity filler 61 in the insulating encapsulation layer and rapidly and uniformly spread along the plane of the insulating encapsulation layer, preventing heat accumulation at any contact point. This structure can significantly improve the capacitor's thermal stability, power cycle life, and breakdown resistance.

[0043] Furthermore, in one embodiment of the present invention, reference continues to be made to... Figure 3 The base material of the first outer insulating encapsulation layer 41 and the second outer insulating encapsulation layer 45 is a polymer; piezoelectric ceramic particles 62 are also dispersed in the first outer insulating encapsulation layer 41 and the second outer insulating encapsulation layer 45, and the surface of the piezoelectric ceramic particles 62 is modified by a silane coupling agent.

[0044] When a pulse capacitor is working, the insulating encapsulation layer may be subjected to an extremely high electric field. This can lead to electromechanical stress and electric field concentration at defects. The combined effect of these two forces often starts from the weakest point, causing tiny cracks, which eventually lead to the breakdown of the dielectric layer and capacitor failure.

[0045] In this embodiment, a polymer is used as the matrix material for the first outer insulating encapsulation layer 41 and the second outer insulating encapsulation layer 45. Polymers offer good flexibility, processability, and insulation, making them a commonly used material for high-performance film capacitors. Optionally, the polymer can be polyimide, polyetheretherketone, or epoxy resin. The piezoelectric ceramic particles 62 can be lead zirconate titanate (PZT), which exhibits a piezoelectric effect: it undergoes slight deformation under an electric field; conversely, it generates a voltage when compressed. The silane coupling agent acts as a molecular bridge, with one end chemically bonded to the hydroxyl groups on the surface of the inorganic material (i.e., the piezoelectric ceramic particles 62), and the other end reacting with or physically entangled with the organic material (polymer matrix).

[0046] When the local electric field in the first outer insulating encapsulation layer 41 or the second outer insulating encapsulation layer 45 increases abnormally, the piezoelectric ceramic particles 62 at that location absorb and dissipate a portion of the electric field energy, converting it into mechanical energy and a small amount of heat energy. During this process, the deformation of the piezoelectric ceramic particles 62 smoothly transfers stress to the surrounding polymer matrix through the strong interface formed by the silane coupling agent, mitigating the direct damage to the polymer matrix caused by electromechanical stress. Furthermore, the silane coupling agent can form chemical bridges between the surface of the piezoelectric ceramic particles 62 and the polymer matrix, ensuring the effective transfer of mechanical stress between the particles and the matrix, enhancing the interfacial bonding between the particles and the polymer matrix, and preventing interface debonding and defects under high field conditions.

[0047] In one embodiment of the present invention, the solid electrolyte is formed by wetting an ionic liquid with a cross-linked polymer network, wherein crown ether or cyclodextrin units are bonded in the cross-linked polymer network, and the crown ether or cyclodextrin units can reversibly coordinate cations in the ionic liquid.

[0048] The presence of crown ethers or cyclodextrins bonded to the polymer network refers to the covalent bonding of crown ethers or cyclodextrins to the main chain or side chains of the cross-linked polymer network (such as polyethylene oxide), ensuring that they do not dissolve or migrate in the ionic liquid and guaranteeing the long-term stability of the electrolyte performance. Reversible coordination means that cations in the ionic liquid can be captured (coordinated) by the cavities of the crown ethers or cyclodextrins, and can also dissociate from these cavities under thermal motion or an electric field. Optionally, the cation can be a lithium ion or a sodium ion.

[0049] Under normal operating conditions, crown ethers or cyclodextrins coordinate with some cations, appropriately regulating the concentration of free ions and ensuring normal ionic conductivity of the electrolyte. Under high-temperature conditions, increased molecular thermal motion shifts the coordination equilibrium towards dissociation, releasing more free cations. This compensates for the decreased ion mobility caused by increased viscosity of the ionic liquid at high temperatures, maintaining stable electrolyte conductivity. Under high-current pulse conditions, ions at the electrode interface are rapidly consumed, reducing local ion concentration. This also drives the dissociation of coordinated ions, replenishing the interfacial ion concentration, alleviating concentration polarization, and improving instantaneous power output capability. This embodiment can extend the capacitor's operating temperature range, while also improving its operational stability and cycle life under high-current pulse conditions, enhancing the capacitor's adaptability to complex operating conditions.

[0050] Furthermore, the coordination strength of crown ether units or cyclodextrins to cations decreases with increasing temperature.

[0051] The capacitor in this embodiment of the invention further includes a temperature-sensitive element 71; Reference Figure 4 In the first electrode unit 42, the high thermal conductivity ceramic three-dimensional skeleton 52 extends at least one thermally conductive branch 521, which is directly thermally coupled to the thermistor portion of the temperature-sensitive element 71. The electrically triggered portion 711 of the temperature-sensitive element 71 is connected in series in the current path formed by the positive electrode lead 201 and the metal conductive three-dimensional skeleton 51. Alternatively, as not shown in the figure, in the second electrode unit 44, the high thermal conductivity ceramic three-dimensional skeleton 52 extends at least one thermally conductive branch 521, which is directly thermally coupled to the thermistor portion 710 of the temperature-sensitive element 71. The electrically triggered portion 711 of the temperature-sensitive element 71 is connected in series in the current path formed by the negative electrode lead 301 and the metal conductive three-dimensional skeleton 51. When the local temperature of the electrode unit is transferred to the temperature-sensitive element 71 through the high thermal conductivity ceramic three-dimensional skeleton 52 and the thermally conductive branch 521 and reaches its operating temperature threshold, the electrically triggered portion 711 is disconnected.

[0052] This embodiment utilizes the high thermal conductivity of the high thermal conductivity ceramic three-dimensional framework 52 as a heat sensing transmission channel, directly connecting it to the thermistor portion 710 of the temperature-sensitive element 71 via an extended thermally conductive branch 521. When overheating occurs in any area within the electrode unit, the high thermal conductivity ceramic three-dimensional framework 52 can quickly conduct heat to the thermally conductive branch 521, and then directly to the thermistor portion 710 of the temperature-sensitive element 71, achieving direct and accurate monitoring of the electrode's internal temperature. When the thermistor portion 710 of the temperature-sensitive element 71 senses that the local electrode temperature exceeds the operating temperature threshold of the temperature-sensitive element 71, the electrical trigger portion 711 of the temperature-sensitive element 71 disconnects, cutting off the current path between the positive lead 201 or the negative lead 301 and the metal conductive three-dimensional framework 51, thus achieving overload protection for the capacitor.

[0053] Furthermore, the operating temperature threshold of the temperature-sensitive element 71 is higher than the rated operating temperature of the capacitor and lower than the thermal decomposition initiation temperature of the solid electrolyte. Because the operating temperature threshold of the temperature-sensitive element 71 is higher than the rated operating temperature of the capacitor, it ensures that the temperature-sensitive element 71 will not malfunction when the capacitor is operating normally within its designed rated operating range, thus guaranteeing the normal function and operational reliability of the capacitor. Since the operating temperature threshold of the temperature-sensitive element 71 is lower than the thermal decomposition initiation temperature of the solid electrolyte, it ensures that the protection system has been triggered and the main circuit has been cut off before the electrode temperature abnormally rises to near the thermal decomposition temperature of the solid electrolyte. This prevents irreversible chemical decomposition of the solid electrolyte and prevents serious faults such as short circuits and explosions caused by electrolyte failure, thus achieving preventative protection.

[0054] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0055] It should also be noted that, in this document, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device 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 terminal device. 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 terminal device that includes the element.

[0056] The technical solutions provided in this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand this application, and the content of this specification should not be construed as a limitation of this application.

Claims

1. A high-density energy storage pulse capacitor, comprising a housing, a positive lead, a negative lead, and a capacitor core sealed within the housing, characterized in that, The capacitor core includes, from top to bottom, a first outer insulating encapsulation layer, a first electrode unit, a solid electrolyte layer, a second electrode unit, and a second outer insulating encapsulation layer; Both the first electrode unit and the second electrode unit include interwoven and penetrating metal conductive three-dimensional skeletons and high thermal conductivity ceramic three-dimensional skeletons, and the metal conductive three-dimensional skeletons and the high thermal conductivity ceramic three-dimensional skeletons are in contact to form a three-dimensional interconnected internal pore network. The positive electrode lead is electrically connected to the metal conductive three-dimensional skeleton in the first electrode unit, and the negative electrode lead is electrically connected to the metal conductive three-dimensional skeleton in the second electrode unit. The solid electrolyte layer is disposed between the first electrode unit and the second electrode unit, and fills the internal pore network of the first electrode unit and the internal pore network of the second electrode unit; It also includes temperature-sensitive elements; In the first electrode unit, the high thermal conductivity ceramic three-dimensional skeleton extends at least one thermally conductive branch, which is directly thermally coupled to the thermistor portion of the temperature-sensitive element, and the electrically triggered portion of the temperature-sensitive element is connected in series in the current path formed by the positive electrode lead and the metal conductive three-dimensional skeleton; or, in the second electrode unit, the high thermal conductivity ceramic three-dimensional skeleton extends at least one thermally conductive branch, which is directly thermally coupled to the thermistor portion of the temperature-sensitive element, and the electrically triggered portion of the temperature-sensitive element is connected in series in the current path formed by the negative electrode lead and the metal conductive three-dimensional skeleton; Specifically, when the local temperature of the electrode unit is transmitted to the temperature-sensitive element through the high thermal conductivity ceramic three-dimensional skeleton and the thermally conductive branch and reaches its operating temperature threshold, the electrical triggering part is disconnected.

2. The high-density energy storage pulse capacitor according to claim 1, characterized in that, The material of the high thermal conductivity ceramic three-dimensional skeleton is boron nitride ceramic or alumina ceramic.

3. The high-density energy storage pulse capacitor according to claim 2, characterized in that, The conductive metal three-dimensional framework is a continuous metal layer deposited on the surface of the high thermal conductivity ceramic three-dimensional framework by chemical vapor deposition or electroplating process. The metal layers are interconnected on the network surface formed by the high thermal conductivity ceramic three-dimensional framework.

4. The high-density energy storage pulse capacitor according to claim 2, characterized in that, The internal pore networks in the first electrode unit and the second electrode unit are gradient-distributed; wherein, in the internal pore network, the average pore diameter of the region near the solid electrolyte layer is smaller than the average pore diameter of the region far from the solid electrolyte layer; and the porosity of the region near the solid electrolyte layer is lower than the porosity of the region far from the solid electrolyte layer.

5. The high-density energy storage pulse capacitor according to claim 1, characterized in that, The substrates of the first and second outer insulating encapsulation layers are three-dimensionally dispersed with sheet-like high thermal conductivity fillers, and the sheet-like high thermal conductivity fillers are oriented in-plane and overlap each other inside the substrate; the sheet-like high thermal conductivity fillers are connected to the high thermal conductivity ceramic three-dimensional skeleton on the outer surface of the first and second electrode units.

6. The high-density energy storage pulse capacitor according to claim 1 or 5, characterized in that, The base materials of the first outer insulating encapsulation layer and the second outer insulating encapsulation layer are polymers; The first and second outer insulating encapsulation layers also contain piezoelectric ceramic particles, the surfaces of which are modified with a silane coupling agent.

7. The high-density energy storage pulse capacitor according to claim 1, characterized in that, The solid electrolyte is formed by impregnating an ionic liquid with a cross-linked polymer network, wherein crown ethers or cyclodextrins are bonded in the cross-linked polymer network, and the crown ethers or cyclodextrins can reversibly coordinate cations in the ionic liquid.

8. The high-density energy storage pulse capacitor according to claim 7, characterized in that, The coordination strength of the crown ether or the cyclodextrin to the cation decreases with increasing temperature.

9. The high-density energy storage pulse capacitor according to claim 1, characterized in that, The operating temperature threshold of the temperature-sensitive element is higher than the rated operating temperature of the capacitor and lower than the thermal decomposition initiation temperature of the solid electrolyte.

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