Batteries can be classified into various types based on their operating principles, materials used, and rechargeability. Different battery types exhibit significant differences in capacity, output voltage, service life, safety performance, and application areas; therefore, selecting the appropriate battery type for practical use requires considering specific device requirements and operating environments. Common battery types currently in use include lead-acid, lithium-ion, nickel-metal hydride (NiMH), nickel-cadmium (NiCd), and fuel cells. Among these, lead-acid and lithium-ion batteries are the most widely used in energy storage, UPS backup power systems, and the new energy sector.
Lead-acid batteries represent a mature technology with a long history of development, consisting primarily of lead-based electrodes and a sulfuric acid electrolyte. They are characterized by low manufacturing costs, high reliability, strong adaptability, and excellent high-current discharge capabilities, making them widely used in UPS backup power, automotive starter batteries, telecommunications base stations, and energy storage systems. Despite drawbacks such as heavy weight, low energy density, and relatively limited cycle life, their technological maturity and ease of maintenance ensure they remain valuable in many scenarios requiring stable power supply.
Lithium-ion batteries are a rapidly evolving class of modern batteries that operate by moving lithium ions between the positive and negative electrode materials during charging and discharging. Compared to traditional lead-acid batteries, lithium-ion batteries offer advantages such as high energy density, light weight, compact size, long cycle life, and fast charging speeds; consequently, they are widely used in mobile phones, laptops, electric vehicles, energy storage systems, and modern UPS equipment. Depending on the cathode material, lithium-ion batteries can be further categorized into types such as lithium iron phosphate (LFP) and ternary lithium batteries; LFP batteries, in particular, are frequently used in energy storage due to their superior safety and longer cycle life.
Nickel-metal hydride (NiMH) batteries, nickel-cadmium (NiCd) batteries, and fuel cells also possess distinct application characteristics. NiMH batteries are known for being environmentally friendly and having stable cycling performance, and they have been widely used in hybrid electric vehicles and portable devices. NiCd batteries offer strong low-temperature tolerance and high-current discharge capabilities, though their application is currently somewhat restricted due to the presence of heavy metals. Fuel cells generate electricity continuously through electrochemical reactions between fuel and an oxidant; characterized by high efficiency and low pollution, they represent a key direction for the future development of new energy technologies. With continuous advancements in materials science and manufacturing technology, the variety of batteries will further expand, offering more options for energy storage, power supply reliability, and the development of green energy.