Toshiba rechargeable battery SCiB™ is a battery that overturns the conventional concepts. In this usage blog, we have shown you how to use SCiB™ in way that overturns conventional concepts.

• Read more about ‘EV BUS’
• Read more about ‘Autonomous Mobile Robot’

In this third article, we will present how space can be saved based on a case study of a UPS (Uninterruptible Power Supply) for a data center.
Why does deploying a UPS with SCiB™ save space in your data center? We would like to think with you on ideas for how to use it.
Please note that this example is a simplified model and may differ from actual operation.

The data center is required to operate 24/7. In normal times, the power is supplied from a power grid, but if the power supply is interrupted due to a power outage, the service will be stopped. In preparation for such situation, auxiliary power supply is necessary to continue service during the time from power supply stop to restoration.

A common auxiliary power supply is a diesel generator, but it may take several minutes to start up and stabilize the power. A battery-powered UPS is used to cover those few minutes. The UPS is never allowed to stop. Therefore, the data center is usually connected to double or triple auxiliary power supply. Because of such a background, the data centers have many power loss prevention devices such as UPS, in addition to servers, and they occupy a lot of land area.

Data Center Image

So, what kind of performance is required for UPS batteries? Let's think about what would happen if a power outage actually occurred.

The following is the action flow from power outage to restoration.

• Immediately upon loss of power from the power grid, the UPS discharges the power stored in its battery to continue operating the servers.
  
• Meanwhile, a diesel generator starts up.
• It takes tens of seconds to a minute after startup for the diesel generator to provide stable power to the data center.
• When the power of the generator is stabilized, switched from "Power supply by battery discharge" to "Power supply from the diesel generator."
• The UPS requires at least 2 to 5 minutes of discharge time. The reason is to respond quickly to several start-up failures of the diesel generator.
• Also, in some regions, there are cases of instantaneous power outages that do not require supply from the diesel generator. In this case, backup must be done using only the power supply from the UPS.

Conventional batteries are basically designed to discharge for a long time.

Let’s think of a battery as a teapot.

A teapot has the same capacity as a teacup, and the amount of tea you can pour depends on the size of its spout. Suppose you want to fill a teacup now. The time limit is 5 minutes.
Because ordinary teapot has a narrow spout, it takes 30 minutes no matter how quickly you try to pour tea. That means you can't fill the teacup in 5 minutes. So, to fill the teacup within the time limit, you need to prepare many teapots and pour them at the same time, but once the teacup is full, the tea will remain in each teapot.
What about SCiB™ teapot? Because the spout of SCiB™ teapot is wider than that of other teapots, you can pour the teacup full in just five minutes. Because of this reason, you don't have to prepare many SCiB™ teapots, and tea does not remain in the teapot after pouring.

In the example above, the size of the spout means how easily the battery discharges, and the size of the teapot means the capacity of the battery.
SCiB™ has the high output feature and can be discharged in just 5 minutes, compared to 30 minutes for conventional batteries. Conversely, if you try to discharge the conventional batteries in 5 minutes like SCiB™, you need to prepare the batteries with 6 times the capacity of SCiB™. In other words, SCiB™ can reduce the battery capacity to 1/6*.

• In practice, there are effects such as electrical resistance, so the battery capacity is reduced by only 1/6 to 1/3.

Smaller battery capacity means that the size of the battery is also reduced. Furthermore, Cooling Systems, Auxiliary Equipment like Power Distribution Systems, Battery Room Fire Extinguishing Facilities and Free Space, which are needed accessorily to Auxiliary Power Supply Systems, can also be reduced. This means that SCiB™ can minimize the entire system space. SCiB™ has a lower energy density than conventional batteries, resulting in a larger volume per unit of capacity, however the space-saving benefits of smaller battery capacity are greater, leading to space-savings in the UPS system.

UPS needs to constantly store power for restoration from unexpected power outages. Conventional batteries degrade faster at higher charge rates. Therefore, it is necessary to ensure sufficient battery capacity to prevent the charging rate becoming too high.

On the other hand, SCiB™ is the battery with long life and low degradation even under high charge rate conditions. SCiB™ does not need to worry about UPS battery deteriorating and replacing batteries. SCiB™ has long-term reliability and does not need UPS updating, thereby reducing life cost.

Reducing UPS battery capacity and battery replacement frequency will be effective use of resources and contribute to the realization of the SDGs.

• UPS | SCiB™ Rechargeable battery | Toshiba (global.toshiba)

In this article, we have presented a case study of SCiB™ deployment into UPS.

• Save space in your data center!
• High power discharge minimizes battery capacity!
• No need for battery replacement makes reducing the total cost of the auxiliary power systems!

We hope you now understand that the SCiB™'s high power discharge and long life lead to the lower total cost. Please click the link below to tell us about your issues and problems. We look forward to coming up with solutions together.