In the power supply system of data centers, uninterruptible backup power is the core guarantee for stable computing operation. With a century-long application history, lead-acid batteries have long dominated the data center backup energy storage market due to their mature and stable performance. Sealed valve-regulated lead-acid batteries require no complex maintenance, adapt to the constant temperature operating environment of data centers, and perfectly match the needs of UPS power supply systems. When the mains power cuts off, the batteries can switch to discharge instantly to ensure seamless power supply and avoid data loss and service interruption. Compared with new-type batteries, they have strong working condition adaptability, excellent anti-voltage fluctuation capability, high safety and low failure rate. With superior reliability and mature technology, lead-acid batteries remain the essential choice for backup energy storage in various data centers.