An uninterruptible power supply (UPS) is crucial to the reliable operation of your data center and IT equipment. A UPS provides clean backup power for connected equipment, protecting those devices and ensuring they remain operational if and when power failures, power surges, or other fluctuations in power occur.
Essentially, a UPS is like your insurance policy against the extremely high cost of unplanned downtime. Given that data centers are more critical than ever before when it comes to generating revenue and enabling e-commerce, downtime is not an option for most businesses today.
UPS systems safeguard your business against shutting down unexpectedly. But the systems are only as reliable as the UPS batteries that support them. Batteries may be the simplest component in a UPS system, but they are arguably the most important. In fact, in a 2021 Ponemon Institute report, Data Center Downtime at the Core and the Edge: A Survey of Frequency, Duration and Attitudes, UPS battery failure was one of the leading root cause of downtime. Even a single bad cell in a string of batteries can compromise a facility’s entire backup system during a power outage, leaving an organization without the essential protection it needs.
Because UPS batteries are so imperative to business continuity, and at the same time, so vulnerable to problems and failure, it’s critical to choose your UPS batteries wisely, understand their limitations, and implement an appropriate battery maintenance program. Doing so will give you greater confidence in the system that is responsible for keeping your business up and running, no matter what.
What are the main types of UPS batteries?
There are three primary types of UPS batteries, and each comes with a different price point, life expectancy, and maintenance requirements. Balancing these three factors helps data center managers determine the best UPS battery type for their specific business requirements.
- Lead-acid UPS batteries. Lead-acid UPS batteries are a proven, reliable, and cost-effective choice for UPS systems. They offer a large amount of storage for a reasonable cost. However, they are heavier, typically require more maintenance, and have a shorter useful life than other newer types of UPS battery technologies.
Lead-acid UPS batteries come in two types:
- Valve-regulated lead-acid (VRLA) UPS batteries. VLRA UPS batteries are also known as sealed batteries. They are typically sealed with polypropylene plastic to prevent any leakage of the battery acid. They also contain a valve that releases the gas pressure inside the battery when it rises too high. VRLA UPS batteries generally have a service life of about five years. They can be hot-swappable and user-replaceable, which helps to simplify maintenance.
- Vented lead-acid (VLA) UPS batteries. Often referred to as flooded batteries, VLA UPS batteries are extremely reliable and typically offer a much longer life than their VRLA counterparts. However, they present some safety concerns and they need to be housed in a separate battery room away from other IT equipment, which can make them difficult to use in some environments.
- Nickel-cadmium (NiCad) UPS batteries. NiCad batteries are a good choice for UPS applications in locations with very high ambient temperatures. They have a 20-year design life and are extremely tolerant of deep discharges. The downside is the price point; NiCad batteries are expensive. They also contain toxic materials, which presents some safety concerns and complicates the disposal and recycling process.
- Lithium-ion UPS batteries. Lithium-ion UPS batteries represent one of the newest UPS battery technologies with several advantages. The initial price point is higher, but the total cost of ownership is often lower because the lithium-ion batteries have at least double the service life of VRLA batteries, they can operate at higher temperatures and require less cooling, and they have reduced maintenance requirements. Lithium-ion batteries are also smaller, lighter, and have faster recharge times for longer runtime. These batteries come with built-in monitoring capabilities for keeping tabs on battery health, making them a highly reliable choice for preventing downtime.
How long do UPS batteries last?
As discussed above, different types of UPS batteries have different average life spans. However, with all types of UPS batteries, it’s important to understand the difference between battery design life and battery service life. Confusing these two concepts can lead to very costly mistakes.
Battery design life is determined by the manufacturer and takes into account cell design and battery aging under controlled conditions in the manufacturer’s lab. However, these factory conditions rarely occur in real-world applications.
That’s why battery service life is the more important figure to consider. Battery service life takes into account how application, installation, real-world operating conditions, and maintenance practices impact battery aging. Specific factors that affect the actual life expectancy of your UPS batteries include:
- Humidity and temperature of the UPS environment
- How often the UPS cycles on and off
- Battery type and storage environment
- Extent of and frequency of maintenance
In reality, when supporting the UPS, batteries often fail in less than half the time stipulated by the manufacturer design life. In general, VRLA battery capacity tends to start diminishing around year three. By year five, it’s likely at or near end of service life. Lithium-ion batteries typically last two to three times longer.
What protection does a UPS battery warranty offer?
Most UPS batteries come with a warranty and the terms can extend anywhere from 24 to 72 months. Battery warranties are designed to ensure and cover the quality of manufacturing and the performance of the batteries. However, it’s important to note that the warranty does not cover normal loss of performance due to age or usage of your batteries.
Furthermore, many warranties are only valid with professional startup of the batteries and with regular annual maintenance. You’ll need to maintain service records in order to substantiate any warranty claims you may need to make. In other words, you cannot rely on the warranty alone to protect your UPS batteries and your business.
Battery service providers like Vertiv can handle the startup and the required ongoing maintenance, and can often handle all aspect of warranty claims, including submitting internal resistance measurement and other important data to the battery manufacturer.
What is the best way to maintain UPS batteries?
With the growing demands on data center managers and in-house IT staff, it’s not uncommon for UPS battery replacement or maintenance to get postponed or overlooked. But UPS battery maintenance really isn’t optional. It’s required for warranty purposes and to meet regulatory requirements from organizations such as the Institute for Electrical and Electronics Engineers (IEEE).
Minimum Battery Maintenance Requirements
As the leading developer of industry standards in a broad range of technologies, IEEE has the most well-known standards regarding UPS battery maintenance practices. In fact, battery manufacturers often cite these standards and require adherence in order to maintain a valid product warranty.
The IEEE standards provide recommended practices for maintenance, testing, and replacement of batteries for stationary applications. They address the frequency and type of measurements that need to be taken to validate the condition of the various UPS battery types:
Four Approaches to Maintaining UPS Battery Health
While the IEEE standards are an excellent place to start, many organizations that want to ensure zero risk of unexpected downtime go further. A robust maintenance program helps optimize battery performance and ensures you get the battery runtime you need when you need it. And, it is the key to facilitating timely replacement of the UPS batteries before they fail and potentially cause downtime for your business.
That said, companies have budgets and other considerations that factor into their maintenance decisions. Based on these variables, such as the organization’s overall level of risk tolerance, most data center operators fall into one of these four approaches to UPS battery maintenance:
- Reactive: Also known as break/fix, this is the riskiest method, as you only take corrective action after an outage occurs. This approach is only viable when the consequences of downtime aren’t viewed as business critical or when the budget is very limited.
- Time-based: A time-based approach involves regular preventive maintenance visits to visually inspect and service the UPS system (including batteries) and is often adequate to comply with regulatory requirements. While a time-based approach has significant benefits over a reactive approach, it’s still risky. It does not account for external factors that can cause significantly shorter-than-expected UPS and battery service life.
- Proactive: In general, the more robust the approach to battery health, the better. A comprehensive maintenance program that includes component assessments and a battery replacement plan is one of the most cost-effective measures you can take to ensure emergency power system reliability and prevent costly downtime.
What is the process for UPS battery replacement, recycling and disposal?
Ideally, you want to replace your UPS batteries before they fail, and the approach to battery maintenance that you choose will help you determine the right time. While lithium-ion batteries can often last the lifetime of a UPS system, with VRLA batteries, most industry experts recommend conservatively replacing them when critical deterioration begins to set in and before five years from the start of service.
Because battery replacement is a major investment, it is recommended to work with a UPS battery expert to ensure the work is done correctly and safely. Your service partner should be able to assist with everything from technical support and installation to battery verification service and testing. A partner can also help ensure proper disposal and recycling of spent batteries in accordance with all applicable environmental regulations.
Battery Services Available From Vertiv
As a global leader in UPS battery services including maintenance, testing, and replacement, Vertiv services 10,000 UPS systems, replaces 9,000 battery strings, and services 2 million battery jars every year in locations around the world. Services include:
Power Assurance Package: Combining the best UPS systems in the business with a five-year protection plan, this service offering is ideal for safeguarding small IT sites.
Battery Service with Ntegrated Monitoring: By combining regular, on-site battery service with remote monitoring and maintenance, you can significantly improve system availability through early detection of potential problems and rapid response to battery defects and degradation.
Warranty + Service Contracts: Vertiv offers a variety of service plans designed to optimize your warranty protection and ensure the ongoing health of all your battery strings.