A high-capacity lithium storage battery is an advanced rechargeable energy device designed to store a large amount of electrical energy in a relatively small and lightweight package. It typically consists of four main components: a cathode, an anode, an electrolyte, and a separator. During charging and discharging, lithium ions move between the cathode and anode through the electrolyte, while electrons flow through an external circuit to provide usable power.The most common high-capacity systems use materials such as layered metal oxides, lithium iron phosphate, or high-nickel compounds for the cathode, and graphite, silicon–graphite composites, or lithium titanate for the anode. By optimizing these materials, engineers can increase energy density, which is the amount of energy stored per unit weight or volume. High energy density is crucial in applications where space and weight are limited, such as electric vehicles, portable electronics, unmanned aerial vehicles, and backup power systems.Another important feature is cycle life, which refers to how many charge–discharge cycles a battery can endure before its capacity significantly declines. High-capacity lithium batteries are designed to maintain stable performance over hundreds or thousands of cycles. This is achieved through improvements in electrode structure, more stable electrolytes, and better management of side reactions that can degrade the internal components over time.Safety is a central focus in the design of high-capacity lithium batteries. As capacity and energy density increase, so does the potential risk of overheating and thermal runaway. To address this, modern cells use advanced separator materials with shutdown functions, flame-retardant additives in electrolytes, and protective coatings on electrode surfaces. At the system level, battery management systems monitor voltage, temperature, and current in real time, preventing overcharge, over-discharge, and short circuits.High-capacity lithium batteries also aim for fast charging performance. By tailoring particle size, electrode thickness, and internal structure, engineers can shorten ion diffusion paths and reduce internal resistance. This allows the battery to accept high charging currents without excessive heat generation or accelerated degradation.From an environmental perspective, the widespread use of high-capacity lithium batteries supports the transition to cleaner energy systems. They enable longer-range electric vehicles, large-scale energy storage for renewable power, and more efficient portable devices. At the same time, attention is increasingly given to raw material sourcing, recycling technologies, and second-life applications to reduce environmental impact and improve resource utilization.Overall, the development of high-capacity lithium storage batteries represents a key technological foundation for future energy systems. Continuous research in materials science, cell design, and intelligent management is expected to further improve energy density, safety, lifetime, and cost-effectiveness, thereby expanding their role in transportation, grid storage, and everyday electronic devices.