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Lithium-ion is changing the space of data centres
Lithium-ion dramatically reduces the footprint and cooling requirements for data centres , presenting some significant advantages over traditionally used VRLA batteries . Victor Avelar , director and senior research analyst at Schneider Electric ’ s Data Center Science Center , explains one particular way Li-ion is changing the game .
The last few years have seen prices for Lithiumion batteries decrease rapidly , meaning that the technology has fast become a viable option for data centre power . Li-ion batteries have been used commercially for over 20 years in various other applications , so why then have they not been adopted as batteries for static UPSs ?
The answer lies in the fact that , like all other applications , Li-ion cells that provided UPS vendors with the right balance of price , energy density , power , safety , and reliability just weren ’ t available . However , advancements in Li-ion chemistries and technologies over the last 10 years have provided UPS vendors with realistic options . These advancements have largely been due to requirements driven by the automotive and electric vehicle industry .
When compared to VRLA batteries , there are a number of key reasons why the Li-ion technology is now paving the way to replace VRLA in future data centre deployments . A recent research paper published by Schneider Electric , White Paper 229 , ‘ Battery Technology for Data Centres : VRLA vs . Li-ion ,’ identifies a 10-year total cost of ownership ( TCO ) analysis , showing Li-ion costs 39 per cent less than VRLA , despite their capital cost premium .
In addition , a sensitivity analysis revealed the drivers and benefits of Li-ion batteries for retrofit and new UPS applications , discussing the effect of temperature on battery life , runtime , and cooling .
Li-Ion presents a number of key benefits for UPS technology over VRLA , these include fewer battery replacements , in some cases perhaps none , required over the life of the UPS , which eliminates the risk of downtime posed by battery replacement . They also weigh around three times less but provide the same amount of energy as their VRLA counterparts . In addition , they deliver over ten times more discharge cycles depending on the battery chemistry and technology deployed , the surrounding ambient temperature , and the depth of discharge required . They also recharge over four times faster and discharge four times slower when the battery is not in use .
However , Li-ion batteries also have two main drawbacks when compared to VRLA . First , they require around two to three times more capex for the same amount of energy , due to the higher manufacturing cost and the cost of the required battery management system . Second , due to the nature of the battery chemistry , they have stricter transportation regulations which will inevitably incur further costs in order to ensure they are delivered safely and undamaged .
At a general level , there are some common characteristics with all lithium-ion cells . However , some specific characteristics
February 2017 | 17