Do you know how to choose a power supply? An uninterruptible power supply (UPS) is one of the most critical power components in a data center. However, the role of batteries used with UPS power is often overlooked. If the utility power in the data center fails, the batteries of the UPS power supply must immediately take over and use its stored energy to support the workload until utility power is restored, the diesel generators can be started or the data center can be safely shut down. Therefore, batteries for UPS power are critical to the data center, and the following highlights the key issues to consider when selecting battery technology for UPS power.
Advantages and disadvantages of various batteries for UPS power supply
Reliability and cost are important requirements for all data centers. UPS power batteries are a major contributor to these priorities, as data center managers require energy-efficient technologies to ensure business continuity, extend operational life, and reduce total cost of ownership (TCO). Choosing a UPS power source requires exploring the advantages and disadvantages of different battery technologies. Which one the user needs to choose has a direct impact on the total cost of ownership (TCO), energy efficiency and charging rate. Traditional lead-acid batteries account for more than 90 percent of the UPS market, but interest in lithium-ion technology has grown in recent years.
That’s because lithium-ion batteries have a smaller footprint and excellent fast-charging capabilities. In addition, lithium-ion batteries have low maintenance requirements and long service life. However, they also require dedicated charging systems, battery management for safe operation, and are not easily recyclable. Therefore, it is worth considering alternatives to traditional lead-acid and lithium-ion batteries, such as thin-plate pure lead (TPPL) batteries, which offer similar performance advantages to lithium-ion batteries and offer advantages over traditional fiberglass separators ( AGM) battery for higher energy efficiency.
The rise of lithium-ion battery technology
The growth of the electric vehicle market has led to the rapid development of lithium-ion battery technology. Lithium-ion batteries have high charge acceptance and fast charging capabilities. This feature is very important in areas where mains power is interrupted frequently. Li-ion batteries use a battery management system (BMS) to control the efficiency and safety of charging. Charging speed, energy efficiency, and battery life are all factors that make Li-Ion batteries attractive for UPS power applications. The maintenance requirements of these batteries are low due to the built-in diagnostics of the battery management system (BMS). Lithium-ion batteries have a design life of 15 to 20 years at 25°C, but they are rarely tested in practice.
Lithium-ion batteries are smaller and lighter than lead-acid batteries. This allows the data center to recover floor space from its UPS power and use it for data center equipment.
Thin Plate Pure Lead (TPPL) Battery Alternative
Thin Plate Pure Lead (TPPL) batteries are an advanced form of lead-acid batteries that offer advantages over glass fiber separator (AGM) batteries. First, thin-plate pure lead (TPPL) batteries have good fast-charging capabilities. Depending on the charging current and voltage parameters used, they can be fully charged within 2 and a half hours. Fiberglass separator (AGM) batteries have a baseline life of 5 to 6 years, while thin plate pure lead (TPPL) batteries are designed to last more than 12 years. Despite the compactness of thin-plate pure lead (TPPL) battery technology Li-ion batteries, solutions with high energy density are possible.
Battery Safety, Recycling and Total Cost of Ownership Considerations
Fast charging, low maintenance costs and long service life are important factors in choosing a UPS battery. But other factors cannot be ignored.
• Safe transportation
Shipping restrictions for lithium-ion batteries do not apply to lead-acid technology. Thin Plate Pure Lead (TPPL) batteries are approved as non-hazardous goods and can be transported by land, sea and air without restriction. However, UN3480 type Li-Ion batteries must be shipped in Partial State of Charge (PSoC). They have to comply with packaging regulations and are limited to dedicated cargo airlines.
•recycle and re-use
Commercial recycling routes have been established for lead-acid batteries. 95% of batteries are recyclable and have an inherent end-of-life value. Lithium-ion batteries are 100% recyclable, but there is a lack of commercial recycling routes. Depending on the chemistry, the end user may have to pay for battery disposal at end of life. This is sure to change in the future as the lithium-ion market continues to grow.
• Total Cost of Ownership (TCO)
Ultimately, total cost of ownership (TCO) is the main driver for choosing a UPS power source using its battery technology. Initial investment, maintenance and operating costs, and useful life all play an important role in determining the total cost of ownership (TCO).
Lithium-ion batteries are more expensive, but are designed to last longer, which has not been proven in practice. Lithium-ion and lead-acid batteries have different charging characteristics. UPS power solutions with lithium-ion batteries require new charging infrastructure, increasing the initial investment. Thin-plate pure lead (TPPL) batteries, on the other hand, use the same charging architecture as standard lead-acid batteries.
in conclusion
The development of lithium-ion technology in electric vehicle applications has created opportunities for other industries such as data centers. Traditional lead-acid batteries, thin-plate pure lead (TPPL) batteries, and lithium-ion batteries have their own advantages and disadvantages. Users choosing a UPS for a data center should keep the pros and cons of each battery type in mind before choosing a UPS solution. Each application has unique requirements, and data centers are well advised to seek expert advice for their use cases. The above is the reason why the battery must be considered first when choosing a UPS power supply, so as to ensure the correctness of the design.