Seizing space and vying for “space superiority” have become critical components of winning future information‑centric wars. Building a robust anti‑space defense system hinges on precision‑guided, high‑energy space weapons—such as directed‑energy systems exemplified by high‑power pulsed laser weapons. These weapons boast extraordinary destructive power and are indispensable for securing victory in tomorrow’s “space battles.”

　　Supercapacitors, the most critical power‑supply component in high‑power pulsed laser weapons, are a new type of energy‑storage device capable of delivering enormous amounts of energy in an extremely short time. They find widespread application in weapon systems and equipment—such as armored vehicles, naval vessels, and spacecraft—that demand substantial pulsed discharge power, and their role on future battlefields should not be underestimated.

　　Forms a “golden duo” with second-generation chemical batteries.

　　To win future information‑centric wars, reliable battlefield power supply for next‑generation weapons and equipment is indispensable, which in turn places new demands on energy‑storage systems. Currently, widely deployed energy‑storage devices include second‑generation chemical batteries such as lead‑acid, nickel‑metal hydride, and lithium batteries, which provide power to individual soldier‑borne systems and hybrid electric drive systems in armored vehicles. However, these technologies have inherent limitations—low power‑density output, slow charging rates, and relatively short cycle life, among others. Under specific operational conditions—such as frigid, snow‑covered environments (where extremely low temperatures prevent low‑power batteries from effectively “waking up” equipment), open plains (where, without cover, a vehicle that has stalled must be recharged promptly), or heavily humid and corrosive terrain (where batteries are prone to corrosion and failure)—these shortcomings can cause equipment to fail, severely undermining combat effectiveness.

　　To prevent equipment from failing on the complex and ever-changing battlefield due to the “weak link” of batteries, supercapacitors were developed through the concerted efforts of researchers.

　　It is a third-generation physical energy storage device that resembles a battery but differs from it in certain respects. Unlike batteries, supercapacitors do not involve chemical reactions during charging or discharging; instead, the storage and release of electrical energy occur through rapid physical processes mediated by electrostatic fields, free from the complex, time‑consuming chemical reactions that constrain conventional batteries. Consequently, supercapacitors can achieve specific power densities hundreds of times greater than those of chemical batteries and can deliver currents ranging from several hundred to several thousand amperes within very short time frames, enabling equipment to be instantly “activated” even at extremely low temperatures.

　　Meanwhile, since supercapacitor charging and discharging are physical processes, they can be charged at high currents and completed in as little as tens of seconds to a few minutes, thereby saving precious time on the battlefield and preventing vehicles and other equipment from becoming “moving targets.”

　　In addition to their high specific power and rapid charging capabilities, supercapacitors boast a cycle life at least a hundred times longer than that of chemical batteries, enabling them to be charged and discharged up to one million times and thereby significantly reducing costs.

　　Based on the aforementioned characteristics, supercapacitors can effectively complement chemical batteries; with appropriate cell‑level design, they can diversify their functions and become a “golden duo” on the informationized battlefield.

　　Engine starting under extreme conditions is a vivid illustration of this golden duo’s “win-win cooperation”: with clearly defined roles and seamless coordination, they truly embody the “power pair” of battlefield equipment. Why is this so? When supercapacitors are paired with lead‑acid batteries in an internal‑combustion‑engine electric‑start system, they effectively protect the battery, extend its service life, and reduce the required battery capacity. Particularly in low temperatures or when the battery is deeply discharged, its discharge capability drops sharply, leading to sluggish starts—or even complete failure to start—for armored vehicles, thereby severely compromising battlefield mobility and response speed. By contrast, supercapacitors boast a wide operating temperature range; even at temperatures below –40°C, their discharge characteristics remain essentially unchanged, maintaining high‑current output. This ensures reliable power supply to the electric‑start system, enabling the vehicle to achieve a successful one‑time activation.

　　It can be regarded as the “energy core” of numerous military systems.

　　If the use of supercapacitors in conjunction with chemical batteries within land‑based armored vehicles’ hybrid electric start systems can be regarded merely as “providing supporting fire,” then when deployed in high‑power weapon systems—such as submarines, naval railguns, and high‑power directed‑energy weapons—their performance truly stands out as unparalleled.

　　Submarine integrated electric propulsion encompasses critical stages such as power generation, transmission, transformation, propulsion, and energy storage, making it a large-scale systems engineering endeavor. In conventional electric drive systems, the power plant supplying the propulsion system and the auxiliary power plant powering the submarine’s onboard equipment were separate subsystems. During low-speed cruising, when only modest power is required, the main power plant would operate at reduced capacity, resulting in inefficiency. By contrast, an integrated electric propulsion system combines these two power sources into a single unit: during low-speed cruise, the high‑power main plant can run at full load while simultaneously supplying power to both the propulsion motors and the submarine’s auxiliary systems; meanwhile, the auxiliary plant can be shut down, maximizing resource utilization and reducing costs. Given the stringent requirements of submarine integrated electric propulsion, supercapacitor modules can serve as an emergency power‑supply backup. During normal operation, they collect and store electrical energy, functioning much like batteries. In emergency situations, when the primary power supply falls short of sustaining the entire system, the supercapacitors’ rapid charge‑discharge capability allows them to instantly release their stored energy, providing a high‑power supplemental source that swiftly restores the system to normal operation, thereby significantly enhancing wartime responsiveness and combat effectiveness.

　　In the realm of combat weapon systems, supercapacitors often play a starring role, holding a pivotal position in cutting-edge military equipment. The electromagnetic railgun, also known as an electromagnetic gun powered by pulsed energy, is a fully electric weapon that employs electromagnetic acceleration to launch projectiles. A prototype railgun consists of two parallel conductive rails, with the projectile sandwiched between them and connected to the power supply. When current flows from one rail through the projectile and back to the other, it generates a strong magnetic field; the interaction between this field and the current produces a powerful Lorentz force that propels the projectile to extremely high velocities. Building on this principle, thousands of capacitors can be connected in parallel along the rails to form a supercapacitor bank. By discharging the stored electrical energy instantaneously, such a system can deliver enormous currents and generate astonishing electromagnetic thrust. If electromagnetic railguns are deployed as direct‑fire support weapons and paired with supercapacitors aboard combat vessels, their destructive capability would be significantly enhanced, helping to secure victory well ahead of schedule.

　　Meanwhile, as a high‑power pulsed power source, supercapacitors can also be employed in directed‑energy weapon power systems. Directed‑energy weapons, also known as “beam weapons,” harness various forms of energy beams to deliver devastating effects. Depending on the carrier of the emitted energy, they can be categorized into laser weapons, particle‑beam weapons, and microwave weapons. These weapon systems share several key characteristics: their energy beams travel at speeds approaching that of light, enabling near‑instantaneous strikes upon target acquisition—“hit where you point”; the beam’s energy is highly concentrated and immense, with output powers ranging from hundreds to thousands of kilowatts, capable of destroying or melting targets; and the beam is tightly focused and delivered with sudden precision, making it difficult for adversaries to detect its origin and leaving them little time to evade or counter it—thus achieving the capability to “eliminate the enemy without a trace.”

　　Many countries around the world are vying to scale the “energy summit.”

　　It is precisely because supercapacitors deliver outstanding performance that they have won favor in many countries. The increasing complexity and diversity of future information‑centric and even intelligent battlefield environments place ever higher demands on the energy density, size, and stability of supercapacitors, thereby accelerating efforts worldwide to develop higher‑performance devices for upgrading and replacing military equipment, thus securing the initiative in warfare.

　　Currently, civilian supercapacitor technology worldwide has reached a high degree of maturity; however, in the military domain, countries remain tight-lipped, typically opting to either customize off-the-shelf products or retrofit industrial‑grade devices for use in military systems. For instance, the U.S. company AVX has introduced aerospace‑grade supercapacitors featuring “base-metal” electrodes and multilayer ceramic dielectrics. These components exhibit capacitance–voltage characteristics comparable to those of supercapacitors with “precious-metal” electrodes (such as gold, silver, and platinum), while delivering higher capacitance in a more compact footprint, thereby reducing board space and overall device weight. The company plans to deploy these devices in both manned and unmanned aerial vehicles, as well as in orbiting satellites, to supply their power needs. Meanwhile, the U.S. firm Evans has developed a large‑scale supercapacitor operating at 120 volts, capable of storing over 35 kJ of energy and delivering power exceeding 20 kW, making it suitable as a compact, ultra‑high‑power pulsed power source for airborne laser weapons.

　　To meet military requirements, South Korea’s LS Mtron has collaborated with the armed forces to produce a series of supercapacitor models, deploying them in fuel‑cell and battery‑electric unmanned combat vehicles, intelligent battlefield robots, and other defense applications, thereby providing technological and equipment support for battlefield unmanned systems. Meanwhile, Japan’s NCC is also developing next‑generation high‑capacity electrical supercapacitors, incorporating novel conductive polymer architectures that reduce both weight and volume while boosting power density. The company plans to partner with U.S. entities on defense projects, further exploring the potential of these devices in high‑power‑output military weaponry.

　　Looking at the development of several military powers, the application of supercapacitors in integrated electric propulsion systems has become quite mature; however, in the realm of pulsed‑power technologies—particularly those exemplified by laser weapons—challenges remain, including low operating voltages and relatively high internal resistance.

　　In recent years, many countries around the world have been dedicated to enhancing the power density of supercapacitors and reducing their internal resistance. It is believed that, in the near future, as supercapacitors become both higher‑energy and more compact, the development of directed‑energy weapons will advance by leaps and bounds: laser guns and laser cannons will become commonplace, and “Star Wars” may no longer remain confined to science fiction films.