By Rob Mather, Director at Power Control.
It is strange to think that battery structure has not really changed for over 50 years. However, with the market shifting and demand for greater lifespan, efficiency and reduced footprint becoming more prevalent, battery manufacturers have upped their game with lithium-ion battery solutions.
The data centre sector in particular is welcoming lithium-ion battery solutions with open arms. When paired with an uninterruptible power supply (UPS) a far more efficient energy storage system can be achieved – reducing power consumption and maintenance costs.
Whilst initially the outlay for a lithium-ion batteries may be more than standard VRLA, the lifespan is far greater so requires fewer battery replacements. However, this cost is slowly being driven down by the increased Li-ion manufacturing capacity.
Over the past ten years a wave of new factories across the globe have already caused an 85% drop in price. As the market grows more comfortable with lithium-ion, a further 603.8GWh is expected to be achieved in the next five years, encouraging the development of the technology, rather than adopting something else.
Why is lithium-ion used in a battery?
Without going too much into the chemistry of a battery, lithium is a very small element, the third smallest in fact after hydrogen and helium. This gives lithium-ion batteries a much better energy density than incumbent technologies such as VRLA. It is also a highly reactive element and rechargeable, making it an ideal material to get a current running through a battery.
Advantages of Lithium-ion batteries in UPS:
- Longevity – A lithium-ion battery lasts up to 10 years under normal circumstances, which is twice as long as a typical VRLA battery. They hold their charge much better and can handle hundreds of charge/discharge cycles. The longevity ensures a return on your investment on the technology.
- Low Maintenance – Lithium-ion batteries have a longer service life and can go longer intervals between servicing. Although they do still require maintenance, the servicing methods are simpler.
- Size/weight ratio – When compared to VRLA batteries, lithium-ion batteries have a 50% smaller footprint for the same power output.
- Recharge time – Where VRLA batteries typically take 6-12 hours, a lithium ion battery takes 30 minutes to one hour. They also hold their charge much better.
- Temperature tolerance – Due to their molecular structure, a lithium ion battery can work reliably at wider temperature ranges than other rechargeable batteries.
What does this mean for data centres?
As the cost barrier for lithium-ion technologies is eroded and new technologies flood the data centre market, data centre owners look to ways of making their infrastructures more advanced, more efficient and more environmentally friendly. The adoption of lithium-ion technology falls alongside other 2020 industry trends such as that of innovative cooling technology, intuitive monitoring software and the drive for data centres to provide their customers with infrastructure resources that would have been unthinkable in previous decades.
Firstly, the amount technologies now being squeezed into modern data centres leaves little room for the necessary critical infrastructure. The overall footprint of a data centre is already vast and in cities where land is at a premium, batteries that occupy large areas affect the economic benefits.
The smaller, lighter and more temperature tolerant lithium-ion UPS solutions are an ideal innovation for reducing the amount of space required for power protection.
Secondly, peak shaving is key for keeping grid connection fees to a minimum, lithium-ion batteries provide an ideal solution for reducing this overall spend and therefore produce economic benefits.
Finally, with the initial cost of lithium-ion batteries decreasing, the integration of this technology is becoming more attainable. This coupled with the longer battery lifespan, reduced maintenance costs and refined recharge time make them an ever more appealing integration for the data centre sector battery market.