In small household off-grid PV energy storage scenarios, the 12V33Ah lead-acid batteries has outstanding cost performance and is a mainstream choice for household distributed energy storage. Matched with small PV panels, it forms an independent energy storage system that absorbs and stores solar energy during the day and releases power at night or on rainy days to supply household lighting, small home appliances and monitoring equipment. Featuring low self-discharge and cycle resistance, it adapts to daily household energy storage conditions with simple maintenance. It can maintain stable basic power consumption even in continuous rainy weather, reduce household reliance on municipal power grids, and suit household energy storage needs in rural and remote areas without stable grid coverage.