With the innovation of battery industry , the lithium battery is applied into more and more industries and replace the lead-acid batteries; 12V series batteries have unique advantages such as high energy ratio, light weight, small size, long lifetime , high safety standard, and high rate. It has become the first choice to replace lead acid and diesel engines in emergency power supply fields.

The lead-acid battery or diesel engine is the regular power source at past years. Considering the lead acid battery has low energy density, heavy mass, low rate discharge efficiency, and non-environmental protection, and so as the diesel engine, it is noisy and not environmentally friendly which can not  meet the requirements of modern portable emergency power sources.. In contrast, lithium battery packs have unique advantages such as high energy ratio, light weight, small size, high cycle life, high safety, and high rate. They have become the first choice for replacing lead acid and diesel engines in many emergency power supply fields.