Summary of Basic Knowledge on Energy Storage

1. Energy storage technologies include electrochemical storage, electromagnetic storage, and mechanical storage. Among these, electrochemical storage is currently one of the most widely used energy storage technologies, encompassing lithium-ion batteries, lead-acid batteries, sodium-sulfur batteries, and flow batteries. Mechanical energy storage involves converting electrical energy into kinetic or potential energy for storage, including pumped-storage hydroelectricity, compressed air energy storage, and flywheel energy storage. Electromagnetic energy storage includes superconducting energy storage and supercapacitor energy storage.

2. Among energy storage solutions for clean energy, lithium-ion battery technology is currently the most widely used and mature. Lithium-ion batteries offer advantages such as high energy density, long service life, and environmental friendliness, making them suitable for large-scale energy storage applications. In addition, new energy storage technologies such as sodium-sulfur batteries and flow batteries are gradually developing; in certain aspects, they may be better suited for specific application scenarios. 3. Lithium-ion battery energy storage systems primarily include the Battery Management System (BMS), Power Conversion System (PCS), and Energy Management System (EMS). The Battery Management System (BMS) is responsible for monitoring battery parameters such as voltage, current, and temperature, and ensuring balance among individual battery cells. The Power Conversion System (PCS) is primarily used for charging and discharging the battery, converting DC power from the battery to AC power for grid connection, or converting AC power from the grid to DC power for charging the battery. The PCS features bidirectional power conversion capabilities, allowing it to control charging and discharging by directing the flow of energy as needed. In energy storage systems, the PCS is one of the key components. The Energy Management System (EMS) serves as the decision-making hub of the energy storage system, acting as its “brain.” Its core functions include optimizing dispatch strategies for safety and providing visualization. The EMS is responsible for optimizing dispatch, formulating multi-scale coordinated control strategies, and automatically maintaining voltage and frequency stability within the microgrid. Energy management systems are generally divided into the device layer, communication layer, and application layer. The device layer relies on energy conversion and acquisition devices (PCS, BMS) for support. The application layer takes forms such as mobile apps and web interfaces, providing management personnel with visual monitoring and operation interfaces. Specific functions include energy conversion decision-making, energy data transmission and acquisition, real-time monitoring and control, O&M management analysis, visual analysis of electrical power and energy, and remote real-time control.