As is well known, for the entire data center, the power supply system with APC uninterruptible power supply equipment as the core is the most essential part to support the smooth operation of the entire data center. Although technology is advancing rapidly, APC UPS, as the last line of defense for stable power supply in data centers, still mostly uses lead-acid materials due to the temporarily high cost of lithium batteries. However, at present, the pressure on data center business is increasing, and the problem of reduced UPS availability is becoming increasingly prominent.
Data shows that nearly 30% of current data center load power outages are related to battery failure. At this point, lead-acid batteries and batteries gradually became a major challenge for data center operation and maintenance personnel. Because lead-acid batteries have strict requirements for temperature stability, they only support about 500 charge and discharge cycles, and require regular discharge. The charging current should not be too high, and the energy density is low, occupying a large area. Nowadays, the mains power is stable, and most APC UPS batteries are in main mode, with a decreasing usage rate year by year. However, lead-acid batteries still need to be regularly charged and discharged to activate their performance and check if their status is stable. The effect of this brush presence is really useless. Even if it is in a float charging state for a long time, ordinary lead-acid batteries still need to be replaced as a whole at least once within ten years. In this context, the trend of lithium battery applications in data centers is becoming increasingly evident.
Lithium batteries have small size, light weight, high energy density, and strong usability. Compared to lead-acid batteries, they have a longer lifespan and do not need to be replaced within ten years. Moreover, the cycling frequency of lithium batteries in the industry can generally reach around 5000 times, and they can also store energy. The so-called energy storage actually refers to the use of lithium batteries that can be quickly charged and discharged multiple times, as well as their high-density characteristics, to store electricity during the municipal radio wave valley period. When the radio wave peak arrives, the stored electricity is transmitted to the data center, thereby reducing the peak pressure on the power grid. This feature will make significant contributions to both green energy conservation and PUE, meeting the dual requirements of government and data center users for PUE and TCO. Relatively speaking, it can be considered a win-win situation.
In foreign countries, due to the characteristics of lithium batteries, they are often used in the field of electric vehicles. For example, the hybrid electric bus provided by Outai for California, USA, has been put into operation since 2008, with a fuel economy index of 106.4kg/h, far higher than the 23.8kg of ordinary diesel generators. Some professional manufacturers of lithium batteries produce lithium batteries that are often used in the energy storage market and industrial fields. For example, Toshiba has applied lithium batteries to large-scale energy storage power plants and household energy storage systems; Another Japanese company, Murata, has developed a new type of lithium battery with a voltage difference of 3.2V and an energy density of 130Wh/Kg, exceeding the current level of lithium batteries.
In China, the application direction of lithium batteries is more inclined to be used as a backup power source for APC uninterruptible power supply, mostly applied in communication base stations and data centers. In the base station, when the mains power is interrupted, the battery pack provides uninterrupted power to the base station to ensure its normal operation. When the mains power is restored, the UPS battery stops supplying power and resumes its inverter function; In data centers, lithium battery UPS, as an energy storage device, can ensure the continuity of output power supply when the mains power supply is interrupted.
According to Uptime’s global data center research, 10% of data centers have already used lithium batteries as backup power. For the data center profession, it is important to maximize the use of existing space and minimize operating costs, especially the cooling energy consumption of APC UPS power supply, battery repair and replacement service costs. Lithium batteries, due to their excellent functions, have become the key to dealing with these problems. For example, the repeated charging and discharging characteristics of lithium batteries can generate economic benefits, which is more than the peak shaving and valley filling of electricity prices. Moreover, lithium batteries do not contain heavy metals such as lead, nickel, chromium, etc., making them the preferred choice for green environmental protection. Therefore, in the future, with the decline of new energy and energy storage costs, it is possible to reduce costs and achieve sustainable development of data centers through lithium battery energy storage.