A high specific energy high power pulse capacitor

Abstract

The application discloses a high specific energy and high power pulse capacitor, and relates to the technical field of capacitors. The capacitor core of the capacitor comprises a first dielectric layer, a second dielectric layer, a composite functional layer, an insulating isolation layer and a buried electrode which are sequentially arranged between a first electrode and a second electrode. The buried electrode is spatially aligned with the composite functional layer through a conductive structure penetrating through the insulating isolation layer. The composite functional layer is composed of an insulating polymer matrix and a voltage trigger functional material dispersed in the insulating polymer matrix. The insulating polymer matrix is used for fixing the voltage trigger functional material and is coupled with the interface of the voltage trigger functional material. The composite functional layer presents a high impedance insulating state when the electric field strength is lower than a preset threshold value, and presents a low impedance conducting state when the electric field strength is higher than the preset threshold value. The energy storage path and the low inductance energy release path are physically separated and decoupled, and the high energy density and the high power density can be simultaneously achieved.

Description

Technical Field

[0001] This invention relates to the field of capacitor technology, and more specifically to a high-energy-density, high-power pulse capacitor. Background Technology

[0002] As the core energy storage component of a pulse power system, the performance of a pulse capacitor directly determines the system's output energy, power level, and size and weight. Two key indicators for measuring the performance of a pulse capacitor are energy density (specific energy, the energy stored per unit volume or mass) and power density (specific power, the rate at which energy is released per unit time).

[0003] In traditional pulse capacitor design, there is an inherent and irreconcilable contradiction between high energy density and high power output. To achieve high energy density, dielectric materials with high dielectric constants and high breakdown field strength must be selected, and the thickness or volume of the dielectric is usually increased to store more charge. However, this leads to an increase in the internal physical dimensions of the capacitor, especially the electrode spacing and current loop area, thus significantly increasing the capacitor's equivalent series inductance (ESL). High ESL severely hinders rapid current changes, limits the discharge rate, and consequently restricts the improvement of power density. Summary of the Invention

[0004] This invention provides a high-energy-density, high-power pulse capacitor, aiming to overcome the aforementioned technical challenges.

[0005] To address the aforementioned problems, embodiments of the present invention disclose a high-energy-density, high-power pulse capacitor, comprising a capacitor core, the capacitor core comprising:

[0006] The discharge terminal, and the first electrode and the second electrode disposed opposite to each other;

[0007] A first dielectric layer is disposed on the side of the first electrode facing the second electrode;

[0008] The second dielectric layer is disposed on the side of the second electrode facing the first electrode;

[0009] A composite functional layer is disposed between the first dielectric layer and the second dielectric layer;

[0010] An insulating layer is disposed between the composite functional layer and the second dielectric layer;

[0011] In addition, the embedded electrode is disposed between the insulating isolation layer and the second dielectric layer, and is spatially aligned with the composite functional layer through a conductive structure that penetrates the insulating isolation layer;

[0012] The composite functional layer consists of an insulating polymer matrix and a voltage-triggered functional material dispersed in the insulating polymer matrix. The insulating polymer matrix is ​​used to fix the voltage-triggered functional material and couple it to the interface, so that the composite functional layer exhibits a high-impedance insulation state when the electric field strength is lower than a preset threshold and a low-impedance conduction state when the electric field strength is higher than the preset threshold.

[0013] The embedded electrode is connected to the discharge terminal.

[0014] In one embodiment of the present invention, the capacitor core further includes a first electrode terminal and a second electrode terminal; in the charging state, the first electrode is connected to the positive terminal of an external charging power supply through the first electrode terminal, the second electrode is connected to the negative terminal of the external charging power supply through the second electrode terminal, and the discharge terminal is in an electrically floating or disconnected state; in the discharging state, the second electrode is connected to the common reference ground of an external load circuit through the second electrode terminal, the discharge terminal is connected to the external load through a switching device, and the first electrode is disconnected from the external charging power supply.

[0015] In one embodiment of the present invention, the voltage-triggered functional material is a conductive particle with an insulating shell coating on its surface.

[0016] In one embodiment of the present invention, the conductive particles are carbon nanotubes or metal nanowires; the insulating shell is made of silicon dioxide or aluminum oxide, with a thickness of 5 nanometers to 20 nanometers.

[0017] In one embodiment of the present invention, the voltage-triggered functional material is zinc oxide varistor ceramic particles.

[0018] In one embodiment of the present invention, the embedded electrode is a conductive layer with a periodically repeating pattern; the number of conductive structures penetrating the insulating layer is multiple, and they are arranged one-to-one with the pattern nodes of the embedded electrode in the plane of the insulating layer, so that the conductive structures and the composite functional layer are spatially aligned.

[0019] In one embodiment of the present invention, the conductive structure is a conductive pore formed on an insulating layer, and the conductive pore is filled with metal or conductive composite material.

[0020] In one embodiment of the present invention, the materials of the first dielectric layer and the second dielectric layer are any one of biaxially oriented polypropylene, polyester, polyphenylene sulfide, or polyvinylidene fluoride film; the thickness of the first dielectric layer and the second dielectric layer is greater than the thickness of the composite functional layer.

[0021] In one embodiment of the present invention, the embedded electrode and the discharge terminal are connected by multiple parallel metal foil strips or metal braided strips.

[0022] In one embodiment of the present invention, the capacitor further includes a housing and an insulating medium encapsulated within the housing, wherein the capacitor core is entirely immersed in the insulating medium; and a high thermal conductivity insulating filler layer, different from the insulating medium, is filled between the outer surface of the capacitor core and the inner wall of the housing.

[0023] The embodiments of the present invention have the following advantages:

[0024] This invention discloses a high-energy-density, high-power pulse capacitor, comprising a capacitor core. The capacitor core includes a first dielectric layer, a second dielectric layer, a composite functional layer, an insulating isolation layer, and a buried electrode sequentially disposed between a first electrode and a second electrode. The buried electrode maintains spatial alignment with the composite functional layer through a conductive structure penetrating the insulating isolation layer. The composite functional layer is composed of an insulating polymer matrix and a voltage-triggered functional material dispersed in the insulating polymer matrix. The insulating polymer matrix is ​​used to fix the voltage-triggered functional material and couple it to the interface, so that the composite functional layer exhibits a high-impedance insulation state when the electric field strength is lower than a preset threshold and a low-impedance conduction state when the electric field strength is higher than the preset threshold. The buried electrode is connected to a discharge terminal independent of the first and second electrodes. This invention physically separates and decouples the energy storage path (via the first and second dielectric layers) from the low-inductance energy release path (via the composite functional layer, conductive structure, and embedded electrode network). This allows the energy storage section to be optimized purely for high energy density, for example, by using thick dielectric materials with high dielectric constant and high withstand voltage, without concern for its discharge rate; while the discharge section can be optimized purely for high power density. Therefore, the capacitor of this invention can simultaneously possess both high energy density and high power density. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below.

[0026] Figure 1 This is a schematic diagram of the capacitor core structure of the high-energy-density high-power pulse capacitor provided in an embodiment of the present invention;

[0027] Figure 2 yes Figure 1 The diagram shows the structural connection between the capacitor core and the external electrical components.

[0028] Figure 3 This is a schematic diagram of the overall packaging structure of the high-energy, high-power pulse capacitor provided in an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0030] To address the trade-off between high energy density and high power output, current technological improvements primarily focus on optimizing dielectric materials (such as developing nanocomposite materials) or improving electrode lead-out structures (such as employing low-inductance designs). However, these improvements are all localized optimizations within the traditional architecture where energy storage and release share the same physical channel and electrical circuit. Regardless of material and structure variations, the stored energy, when released, must pass through the same energy storage medium region and the same circuit comprised of the same pair of main electrodes. This means that the polarization response speed of the dielectric and the intrinsic inductance determined by the geometry of the main circuit together constitute the limitation on the discharge rate.

[0031] In view of this, embodiments of the present invention provide a high-energy-density, high-power pulse capacitor, including a capacitor core, as shown in the reference. Figure 1 and Figure 2 The capacitor core includes:

[0032] The discharge terminal, and the first electrode and the second electrode disposed opposite to each other;

[0033] A first dielectric layer is disposed on the side of the first electrode facing the second electrode;

[0034] The second dielectric layer is disposed on the side of the second electrode facing the first electrode;

[0035] A composite functional layer is disposed between the first dielectric layer and the second dielectric layer;

[0036] An insulating layer is disposed between the composite functional layer and the second dielectric layer;

[0037] Furthermore, an embedded electrode is disposed between the insulating isolation layer and the second dielectric layer, and is spatially aligned with the composite functional layer through a conductive structure penetrating the insulating isolation layer; wherein, the composite functional layer is composed of an insulating polymer matrix and a voltage-triggered functional material dispersed in the insulating polymer matrix, the insulating polymer matrix is ​​used to fix the voltage-triggered functional material and couple it to the interface, so that the composite functional layer exhibits a high-impedance insulation state when the electric field strength is lower than a preset threshold, and exhibits a low-impedance conduction state when the electric field strength is higher than the preset threshold; the embedded electrode is connected to the discharge terminal.

[0038] In this embodiment of the invention, the first dielectric layer and the second dielectric layer can be composed of dielectric materials with high dielectric constant and high breakdown field strength. Their function is to polarize under the action of an electric field and store electrical energy in the form of an electrostatic field. Optionally, the materials of the first dielectric layer and the second dielectric layer are any one of biaxially oriented polypropylene (BOPP), polyester (PET), polyphenylene sulfide (PPS), or polyvinylidene fluoride (PVDF) based films; the thickness of both the first dielectric layer and the second dielectric layer is greater than the thickness of the composite functional layer.

[0039] The composite functional layer, disposed between the first and second dielectric layers, is the functional switch incorporated into the capacitor core in this invention. The composite functional layer comprises an insulating polymer matrix (such as epoxy resin, silicone rubber, or polyimide) and a voltage-triggered functional material uniformly dispersed therein (described in detail later). This composite functional layer exhibits unique nonlinear current-voltage characteristics: when the applied electric field strength is below a preset threshold, it presents a high-impedance insulating state; when the electric field strength is above the preset threshold, it transitions to a low-impedance conducting state within nanoseconds to microseconds.

[0040] An insulating layer is disposed between the composite functional layer and the second dielectric layer. It is a continuous and dense insulating film, and the material can be polyimide (PI), polyvinyl alcohol (PVA), etc. The insulating layer can physically ensure reliable electrical isolation between the composite functional layer and the embedded electrode, preventing leakage during charging.

[0041] A conductive structure refers to one or more miniature conductive structures that penetrate the insulating layer, with its upper end face in contact with the composite functional layer and its lower end face in contact with the embedded electrode. Under steady-state charging conditions, since the composite functional layer is in a high-impedance insulating state, there is no stable potential difference between the two ends of the conductive structure, and it does not form a conductive channel. When discharge is triggered and the composite functional layer switches to a low-impedance conducting state, the potential at both ends of the conductive structure is instantaneously flattened, forming a low-impedance current path.

[0042] The embedded electrode is disposed between the insulating layer and the second dielectric layer. Specifically, the embedded electrode can be a patterned metal thin film or a network of metallized thin films. The embedded electrode does not directly participate in energy storage, but serves as an intermediate path for a dedicated low-inductance discharge channel, maintaining precise spatial alignment with the upper composite functional layer through the aforementioned conductive structure.

[0043] The capacitor core also includes a first electrode terminal and a second electrode terminal; the first electrode terminal, the second electrode terminal, and the discharge terminal serve as the capacitor's three external electrical interfaces. The discharge terminal is an external electrical interface independent of the first and second electrode terminals. The discharge terminal can be directly connected to the embedded electrode via a low-inductance connection to serve as a dedicated output port for high-power pulse current.

[0044] In one embodiment of the present invention, the embedded electrode and the discharge terminal are connected by multiple parallel metal foil strips or metal braided strips, thereby achieving lower parasitic inductance and improved high current carrying capacity.

[0045] The core inventive concept of this invention lies in physically constructing and isolating two functional paths within a capacitor: one dedicated to high-efficiency, high-energy-density charging and energy storage, and the other dedicated to ultra-fast, low-inductance, high-power discharge and energy release. Switching from a high-impedance insulation state to a low-impedance conduction state is achieved through a composite functional layer, enabling instantaneous and automatic switching from the energy storage path to the energy release path. Specifically, this invention physically separates and decouples the two paths by assigning energy storage functionality to the first and second dielectric layers, and rapid energy release functionality to the energy release channel composed of the composite functional layer and embedded electrode layers. Thus, the first and second dielectric layers can be optimized purely for high energy density, and the energy release channel can be optimized purely for low inductance and fast response. This eliminates the limitation of the slow polarization relaxation time and large inductance of the main electrode circuit inherent in the high-energy-density dielectric, resulting in a power density increase of more than an order of magnitude.

[0046] The capacitor charging process in this embodiment of the invention is as follows:

[0047] refer to Figure 1 and Figure 2 In the charging state, the first electrode is connected to the positive terminal (represented as "+" in the diagram) of the external charging power supply through the first electrode terminal and the closed first switch K1. The second electrode is connected to the negative terminal (represented as "-" in the diagram) of the external charging power supply through the second electrode terminal and the closed second switch K2. The third switch K3 is open, and the discharge terminal is in an electrically floating or open state. After the power supply applies voltage, an electric field is established between the first and second electrodes. At this time, since the electric field strength is lower than the preset threshold, the composite functional layer is in a high-resistance insulating state, equivalent to an insulator. The voltage drives the accumulation of charge on the surfaces of the first and second electrodes, and through displacement current, a polarized electric field is synchronously established in the series-connected first dielectric layer, composite functional layer (high-resistance state), insulating isolation layer, and second dielectric layer. In this process, the charge mainly accumulates on the surfaces of the first and second electrodes, and generates strong polarization inside the first and second dielectric layers, thereby converting electrical energy into polarization energy in the dielectric and storing it. Although the embedded electrode in the middle is in an electric field, it is surrounded by insulating layers (i.e., an insulating isolation layer and a second dielectric layer) and is not connected to any external power source. Its potential automatically adjusts to an intermediate value, leaving it in a suspended state and not participating in energy storage. At this stage, the capacitor behaves as a traditional energy storage device with high voltage and high capacitance, and its energy density is determined by the materials and thicknesses of the first and second dielectric layers.

[0048] The capacitor discharge process in this embodiment of the invention is as follows:

[0049] refer to Figure 1 and Figure 2 In the discharge state, the second electrode is connected to the common reference ground (GND) of the external load circuit through the second electrode terminal and the closed second switch K2. The discharge terminal is connected to the external load through the third switch K3. The first switch K1 is open, and the first electrode is disconnected from the external charging power supply. At the instant the loop switch closes, the entire potential difference between the first electrode and the second electrode is applied to the first and second dielectric layers. Due to the change in the loop, the electric field strength experienced by the composite functional layer instantaneously exceeds its preset threshold. The composite functional layer switches from a high-impedance insulation state to a low-impedance conduction state in a very short time. This transition is physically equivalent to partially short-circuiting the first electrode side and the embedded electrode through the conductive composite functional layer and conductive structure.

[0050] The energy stored in the first electrode and the first dielectric layer is no longer released through the traditional high-inductive-resistance path (via the second dielectric layer to the second electrode), but is rapidly discharged through a newly activated low-inductance channel path. This discharge occurs sequentially through the first electrode (high-voltage charge), the first dielectric layer (displacement current), the composite functional layer (low-impedance conduction state), the conductive structure, the embedded electrode, the discharge terminal, the external load, and finally the second electrode and its terminal, ultimately reaching ground. A large pulse current flows from the discharge terminal, performs work on the load, and then flows back to the common ground terminal of the second electrode, forming a complete discharge circuit. During this stage, the capacitor behaves as a pulse current source with ultra-low equivalent series inductance (ESL), and the power density can be determined by the low-inductance design of the embedded electrode network and the independent discharge terminal.

[0051] In one embodiment of the present invention, the voltage-triggered functional material is a conductive particle with an insulating shell coating on its surface. In this embodiment, the preset threshold of the composite functional layer can be determined based on the dielectric properties of the insulating shell. When the electric field strength is lower than the preset threshold, the conductive particles are effectively isolated by the continuous insulating shell and the polymer matrix, resulting in a large distance between the particles, preventing electrons from transitioning, and the composite material as a whole exhibits high impedance, thus making the composite functional layer exhibit a high-impedance insulating state. When the applied electric field strength exceeds the dielectric breakdown strength of the insulating shell, electrons pass through the insulating barrier, forming a tunneling current between adjacent particles. The Joule heating generated by localized conduction may further lead to localized damage to the shell, triggering an avalanche effect. Within nanoseconds to microseconds, a large number of through-conductive pathways are formed in the composite material, causing the overall resistance to drop sharply by 3-6 orders of magnitude, exhibiting a low-impedance state, thus making the composite functional layer exhibit a low-impedance conductive state.

[0052] Alternatively, the conductive particles can be carbon nanotubes (CNTs) or metal nanowires; the insulating shell can be made of silicon dioxide or aluminum oxide with a thickness of 5 to 20 nanometers. Carbon nanotubes have a high aspect ratio, making it easy to form a conductive network in the matrix. Metal nanowires can be, for example, silver nanowires or copper nanowires, possessing extremely high intrinsic conductivity. The thickness of the insulating shell determines the preset threshold value; a thinner shell results in a lower threshold electric field and a faster response, but also increases the manufacturing difficulty and leakage current risk. In this embodiment of the invention, an insulating shell with a thickness of 5 to 20 nanometers is preferably used, which can balance response speed and safety.

[0053] In another embodiment of the present invention, the voltage-triggered functional material is zinc oxide varistor ceramic particles. Zinc oxide varistor ceramic particles are a commercially available mature composite material, with a microstructure consisting of conductive zinc oxide grains and an insulating grain boundary layer surrounding the grains. This embodiment of the invention utilizes the inherent nonlinear current-voltage characteristics of the zinc oxide varistor ceramic particles to achieve a switching function. When the electric field strength is below a preset threshold, the grain boundary layer between the zinc oxide particles forms a high Schottky barrier, blocking electron flow and resulting in high impedance. When the electric field strength is above the preset threshold, sufficient to allow electrons to tunnel through the grain boundary barrier via quantum tunneling, the resistance drops sharply. It is worth noting that this process of the zinc oxide varistor ceramic particles is reversible; the high-resistance state is restored after the electric field is removed.

[0054] In this embodiment, the preset threshold is the Schottky barrier formed by the grain boundary layer, which can be controlled by modulating the formula and content of ceramic powder in the zinc oxide varistor ceramic particles.

[0055] Understandably, maintaining spatial alignment means that specific areas of two components coincide or overlap in the vertical projection direction, preparing the position for the current to establish a direct physical connection under specific conditions. However, they are still separated by an insulating layer at the physical contact surface. In one embodiment of the present invention, the embedded electrode maintains spatial alignment with the composite functional layer through a conductive structure penetrating the insulating layer. This can be achieved through the following structure: the embedded electrode is a conductive layer with a periodically repeating pattern; the number of conductive structures penetrating the insulating layer is multiple, and they are arranged one-to-one with the pattern nodes of the embedded electrode in the plane of the insulating layer, so that the conductive structures maintain spatial alignment with the composite functional layer.

[0056] This embodiment is based on a patterned design of embedded electrodes, with conductive structures set at each preset node or key location. The embedded electrodes are conductive layers with a periodically repeating pattern, ensuring uniform charge collection and current transfer across the entire electrode plane, avoiding localized overheating or uneven discharge, and also facilitating design and manufacturing. Multiple conductive structures penetrate the insulating layer, forming a high-density vertical interconnect array that strictly coincides with a specific location on the embedded electrode pattern. This one-to-one correspondence ensures that when the composite functional layer is widely conductive, current can flow vertically from any conductive point on its lower surface through the nearest conductive structure to the embedded electrode, achieving uniform and efficient charge collection and low-inductance transmission.

[0057] Optionally, the conductive structure is set to correspond one-to-one with the nodes of the embedded electrode pattern. If the embedded electrode is a grid, the conductive structure is precisely located below each intersection of the grid lines. Nodes are where current naturally converges and paths intersect; placing vertical channels at these locations yields the highest efficiency.

[0058] In this embodiment of the invention, a conductive structure connects the composite functional layer and the embedded electrode. During charging, the composite functional layer is in a high-impedance insulating state, and the entrance above the conductive structure is closed, so the charge can only accumulate and store energy on the first dielectric layer and the second dielectric layer. During discharging, the composite functional layer becomes a low-impedance conductive state, and the charge between the first electrode and the first dielectric layer is conducted through the composite functional layer to multiple conductive structures and then to the embedded electrode, and then rapidly discharged through the discharge terminal connected to the embedded electrode.

[0059] In one embodiment of the present invention, the conductive structure is a conductive pore formed on an insulating layer, the pore being filled with metal or a conductive composite material. The conductive pore can be formed on a pre-formed insulating layer using processes such as laser ablation or reactive ion etching, and then the conductive structure is formed by electroplating, chemical deposition, or filling with conductive paste. The metal filling the conductive pore can be copper or silver. The conductive composite material filling the conductive pore can be conductive silver paste. Optionally, multiple conductive pores can be formed on the insulating layer, and these pores are uniformly distributed on the insulating layer. Optionally, the diameter of the conductive pore is 10 micrometers to 50 micrometers, and the depth is equal to the thickness of the insulating layer.

[0060] refer to Figure 3The capacitor in this embodiment of the invention also includes a shell and an insulating medium encapsulated within the shell, with the capacitor core entirely immersed in the insulating medium. Furthermore, a high thermal conductivity insulating filler layer, different from the insulating medium, is filled between the outer surface of the capacitor core and the inner wall of the shell. In traditional single-impregnated capacitors, the thermal resistance of the heat path from the core to the shell is relatively high, easily causing heat accumulation inside the core under repeated high-power pulses, leading to overheating and aging of the dielectric. Therefore, this embodiment of the invention utilizes an internally impregnated insulating medium to ensure no air gaps between layers and components within the core, preventing partial discharge and providing basic, uniform heat dissipation. The high thermal conductivity insulating filler layer is typically a high thermal conductivity silicone gel, epoxy resin, or phase change material, with a thermal conductivity much higher than that of ordinary insulating oil. It tightly adheres to the outer surface of the core, establishing an ultra-low thermal resistance path towards the shell, which can improve the thermal stability and pulse cycle life of the device.

[0061] like Figure 3 As shown, in this invention, when the capacitor core is completely immersed in an insulating medium, the first electrode is led out to the outside of the outer casing through the first electrode terminal in sequence through the insulating medium and the high thermal conductivity insulating filling layer. The second electrode is led out to the outside of the outer casing through the second electrode terminal in sequence through the insulating medium and the high thermal conductivity insulating filling layer. The discharge terminal is also led out to the outside of the outer casing through the insulating medium and the high thermal conductivity insulating filling layer in sequence.

[0062] 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.

[0063] It should also be noted that in this document, the terms “center,” “upper,” “lower,” “left,” “right,” “vertical,” “horizontal,” “inner,” and “outer,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the present invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0064] Furthermore, relational terms such as “first” and “second” are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations, nor should they be construed as indicating or implying relative importance. Moreover, 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 process, method, article, or terminal device.

[0065] The technical solution provided by the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the present invention, and the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A high-energy-density, high-power pulse capacitor, comprising a capacitor core, characterized in that, The capacitor core includes: The discharge terminal, and the first electrode and the second electrode disposed opposite to each other; A first dielectric layer is disposed on the side of the first electrode facing the second electrode; A second dielectric layer is disposed on the side of the second electrode facing the first electrode; A composite functional layer is disposed between the first dielectric layer and the second dielectric layer; An insulating layer is disposed between the composite functional layer and the second dielectric layer; In addition, an embedded electrode is disposed between the insulating isolation layer and the second dielectric layer, and is spatially aligned with the composite functional layer through a conductive structure penetrating the insulating isolation layer; The composite functional layer is composed of an insulating polymer matrix and a voltage-triggered functional material dispersed in the insulating polymer matrix. The insulating polymer matrix is ​​used to fix the voltage-triggered functional material and couple it to the interface, so that the composite functional layer exhibits a high-impedance insulation state when the electric field strength is lower than a preset threshold and a low-impedance conduction state when the electric field strength is higher than the preset threshold. The embedded electrode is connected to the discharge terminal.

2. The high-energy-density, high-power pulse capacitor according to claim 1, characterized in that, The capacitor core also includes a first electrode terminal and a second electrode terminal; In the charging state, the first electrode is connected to the positive terminal of the external charging power supply through the first electrode terminal, the second electrode is connected to the negative terminal of the external charging power supply through the second electrode terminal, and the discharge terminal is in an electrically floating or disconnected state. In the discharge state, the second electrode is connected to the common reference ground of the external load circuit through the second electrode terminal, and the discharge terminal is connected to the external load through a switching device. The first electrode is disconnected from the external charging power supply.

3. The high-energy-density high-power pulse capacitor according to claim 1 or 2, characterized in that, The voltage-triggered functional material is a conductive particle with an insulating shell coating on its surface.

4. The high-energy-density, high-power pulse capacitor according to claim 3, characterized in that, The conductive particles are carbon nanotubes or metal nanowires. The insulating shell is made of silicon dioxide or aluminum oxide and has a thickness of 5 nanometers to 20 nanometers.

5. The high-energy-density high-power pulse capacitor according to claim 1 or 2, characterized in that, The voltage-triggered material is zinc oxide varistor ceramic particles.

6. The high-energy-density high-power pulse capacitor according to claim 1, characterized in that, The embedded electrode is a conductive layer with a periodically repeating pattern. The conductive structure penetrating the insulating layer is multiple, and is arranged in a one-to-one correspondence with the pattern nodes of the embedded electrode in the plane of the insulating layer, so that the conductive structure and the composite functional layer are spatially aligned.

7. The high-energy-density, high-power pulse capacitor according to claim 1, characterized in that, The conductive structure is a conductive pore formed on the insulating layer, and the conductive pore is filled with metal or conductive composite material.

8. The high-energy-density, high-power pulse capacitor according to claim 1, characterized in that, The materials of the first dielectric layer and the second dielectric layer are any one of biaxially oriented polypropylene, polyester, polyphenylene sulfide or polyvinylidene fluoride film; The thickness of both the first dielectric layer and the second dielectric layer is greater than the thickness of the composite functional layer.

9. The high-energy-density, high-power pulse capacitor according to claim 1, characterized in that, The embedded electrode and the discharge terminal are connected by multiple parallel metal foil strips or metal braided strips.

10. The high-energy-density, high-power pulse capacitor according to claim 1, characterized in that, It also includes a housing and an insulating medium encapsulated within the housing, wherein the capacitor core is entirely immersed in the insulating medium; Between the outer surface of the capacitor core and the inner wall of the outer casing, there is a high thermal conductivity insulating filler layer that is different from the insulating medium.

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