It’s hard to imagine today, but there was a time when a mobile phone wouldn’t fit in a lunch box, let alone a pocket. Those first-generation cell phones were heavy bricks, while early laptops seemed more like a dense law school textbook

The chips, circuitry and electronics were part of the problem, but the larger issues —literally and figuratively — were the batteries needed to power those devices. The breakthrough came in the form of lithium-ion batteries. Today’s smartphones and tablets simply do not exist without lithium-ion technologies.

More recently, we’re seeing lithium-ion technologies introduced into the data center, delivering many of the same benefits if not the groundbreaking sort of impact seen in consumer electronics. This may not be familiar technology to many data center operators, but calling it “new” would be a misnomer.

Still, valve regulated lead acid (VRLA) batteries remain the most common choice for data center UPS systems. Their job is to provide bridge power from grid to generator and, when monitored and maintained effectively, they get the job done. But they’re also big, heavy, don’t hold a charge long, require quite a bit of maintenance and must be replaced frequently. Without dedicated monitoring and attentive maintenance, VRLA batteries are unquestionably the weak link in the data center power chain.

Before lithium-ion, there really weren’t any better options. But today’s data centers increasingly are taking advantage of a new breed of lithium-ion technologies that deliver an improvement over the benefits that make them a fit for consumer electronics — and a stark contrast to traditional VRLA batteries. The market is taking notice. A report on the global data center UPS market from Research and Markets, suggests lithium-ion batteries are expected to account for 35% of the market share for UPS batteries by 2025.

Compared to VRLA, lithium-ion batteries offer:

  • Smaller footprint: Lithium-ion batteries store more energy in a smaller space, making them 70% smaller and 60% lighter than VRLA. In some cases, this makes in-row battery storage possible, reducing cable runs and simplifying monitoring and maintenance.
  • Longer life: Lithium-ion batteries routinely last two-to-three times as long as VRLA and often considerably longer, reducing the most significant cost associated with UPS batteries: replacement. In fact, VRLA batteries typically need to be replaced multiple times before a single lithium-ion replacement.
  • Reduced weight: Lithium-ion batteries are up to 60% lighter than VRLA, allowing for greater flexibility in energy storage locations and, potentially, reduced facility construction costs. Lithium-ion batteries also open up the capability to locate batteries in places that have been off limits to heavy VRLA counterparts, such as high-rise buildings.
  • Lower total cost of ownership: The up-front costs of lithium-ion batteries are anywhere from 1.5 to 1.75 times the norm for VRLA — but dropping. When considering the longer lifespan, reduced maintenance requirements and reduced cooling costs, TCO pretty clearly favors lithium-ion.

The obvious question is why didn’t lithium-ion gain traction in the data center space earlier? Maturity of lithium-ion technologies certainly had something to do with it. When your livelihood depends upon data center availability, the idea of introducing an untested technology into the facility is understandably daunting. Keep in mind, some of the early headlines related to lithium-ion revolved around mishaps with hoverboard and laptop batteries. In those days, the status quo didn’t seem so bad. It’s worth noting that other alternatives continue to emerge — thin plate pure lead (TPPL) batteries, with their wide thermal tolerance and reliable performance, are an example.

The lithium-ion batteries and chemistries used with today’s UPS systems boast different chemistries, higher cycle counts and advanced design and construction flexibilities compared to consumer models. Lithium iron phosphate (LFP), lithium-ion manganese oxide (LMO) and lithium nickel manganese cobalt oxide (NMC) are the preferred options in the data center, each offering certain advantages based on load and desired operating time. Battery management systems are integral to fully leveraging lithium-ion capabilities, but those systems are necessary in the data center regardless of the type of batteries being used.

Early adoption of lithium-ion batteries lagged in part because standards and codes for their deployment in data centers didn’t exist or were out of step with newer technologies. That’s changing, however, with updates to UL and NFPA codes and standards better reflecting the state of the art and validating the mature state of today’s lithium-ion solutions. The hurdles slowing widespread adoption are falling by the wayside.

Bottom line: Today’s lithium-ion technologies present safe, reliable alternatives to VRLA with many built-in advantages for data center applications.