With the advantages of low-voltage safety and flexible assembly, 12V lead-acid batteries are widely used in various small off-grid photovoltaic scenarios. In civil scenarios, they power off-grid rural households, outdoor RVs and courtyard photovoltaic lighting systems, meeting the power demand of daily lighting and small household appliances. In engineering scenarios, they adapt to solar street lights, monitoring energy storage and field meteorological monitoring equipment. Users can expand capacity and boost voltage by parallel and series connection of batteries to build energy storage systems of different powers. Featuring low-temperature resistance and impact resistance, they adapt well to outdoor environments and stably cope with photovoltaic power generation fluctuations, serving as core supporting equipment for small off-grid photovoltaic systems.