Valve-regulated sealed lead-acid batteries are mainstream backup energy storage batteries for data centers, matching UPS power supply systems. Adopting liquid-starved sealed structure, they produce no acid mist and need no daily electrolyte refilling, suitable for enclosed cabinet installation. Made of lead-calcium alloy plates, they feature low internal resistance and stable discharge performance for emergency power backup. With 12V single-cell rated voltage, their C10 standard capacity ranges from 24Ah to 250Ah, expandable via series-parallel connection. Their monthly self-discharge rate is below 1.5%, with 10-12 year service life at room temperature. Low procurement and operation cost makes them ideal for small and medium-sized data centers.