Why do UPS with lithium batteries cost more than lead acid versions?

The most common type of battery used in an uninterruptible power supply is a valve regulated lead acid (VRLA) battery. These are manufactured in high volumes and can be charged by a standard UPS battery charging circuit. Lithium batteries of the power used in a UPS system cost more and require a more sophisticated battery management circuit. These two factors add to the cost of the UPS which can be up to 20-30% more expensive than a UPS with a lead acid battery set.