Why lead acid trumps lithium for data centre batteries

Lithium ion batteries may be gaining traction in the automotive world, but for datacenters, advanced lead acid technology can deliver lower costs – even when the batteries are used for additional tasks, such as peak shaving, according to EnerSys.

Applications manager Mark Coughlin says the firm’s advanced thin plate pure lead technology is often the most economic technology for data centres.

While lithium ion suits high cycling applications, data centre batteries are primarily used in standby mode, kicking in only when required to maintain power during outages before generators kick in.

“In terms of overall costs and cost per cycle, advanced thin plate lead acid batteries, with improved cyclic capability, are very attractive compared to lithium,” says Coughlin.

“EnerSys has undertaken a lot of studies around cycle life and design life – and the cost of lithium is higher than lead acid.”

Data centre operators therefore must consider total cost of ownership over the lifetime of UPS equipment, typically 15-years, says Coughlin.

“Our analysis shows advanced thin plate pure lead acid batteries, in terms of total cost of ownership, provides benefits over lithium.”

Even where higher cycles are required, such as using batteries for peak shaving and grid services, advanced lead acid batteries can prove “very attractive in terms of overall costs and cost per cycle compared to lithium,” Coughlin suggests.