Advantages of Lithium Ion UPS Systems

Lithium ion batteries offer several times the energy and power density of the most common types in current UPS systems compared to lead-acid batteries. Their energy density is up to 200Wh/kg, which is three times as much as nickel metal hydride and four times of that of lead acid. As a result, UPSs built with lithium ion batteries take up only about one-third or less of the space of lead-acid-based solutions that provide the same power. This smaller footprint means lower cooling requirements, at least about two-thirds less weight. This means that customers have more flexibility in where the system is installed, and can often avoid costly building renovations.

Lithium ion batteries can also withstand a wider temperature range than lead acid batteries. As a rule of thumb, every 10°C (18°F) increase in ambient temperature over 25°C (77°F) cuts the life of a lead acid battery in half. When used at low discharge rates, lithium ion batteries are much less sensitive to temperature fluctuations and can accept temperature spikes with little to no impact on battery life. For very short run times and high discharge rates, such as in UPS applications, lithium ions are still temperature sensitive, but to a lesser extent.

Lithium ion batteries are always equipped with a sophisticated battery monitoring system (BMS) that provides a clear picture of the battery operating time and health. It is essentially the same technology that allows you to easily see the battery life of your smartphone. In contrast, lead acid batteries rely on chemical composition, so it is difficult to predict exactly when they will fail. Think about the battery of your car: one day it might work just fine, but the next day it is a little cold and the battery will fail without warning. This does not happen with lithium ion batteries.

This leads to the ultimate benefit of lithium ion batteries for UPS: increased life expectancy. Theoretically, the life expectancy of lead acid batteries used in UPS systems is 10 years. But due to the limitations of being able to determine their actual health and life expectancy, most customers actually replace them after 5 or 6 years. In contrast, the most suitable lithium ion batteries for UPS are expected to last more than 10 years, reducing the burden and cost of battery replacement, as well as the risk of downtime or load interruption during maintenance.

Advantages of Lithium Ion UPS Systems