The important relationship between lithium battery and communication backup power

This is an era of data explosion, with clouds and pipelines carrying data and bringing people into the era of big data. The main equipment continues to evolve, and the network energy equipment has also developed rapidly. The backup power supply that guarantees the uninterrupted power supply of the communication equipment also needs to speed up the pace, adding to the era of big data.

Lead-acid battery technology is shaped, pollution, low life and low energy density are difficult to solve

Lead-acid batteries have been developed for more than 150 years. Because of their low cost, mature technology and convenient maintenance, they have been the most widely used energy storage batteries in communication power supplies, but lead-acid batteries are subject to theoretical characteristics and Product features, it is difficult to have significant improvements in the future.

The first is a short cycle life. Even lead-acid batteries with relatively good cycle performance are frequently used in areas with poor grid quality and can only last for one year. In addition, the life of a lead-acid battery is greatly dependent on its operating temperature. When the temperature increases, the corrosion and water loss of the plate are accelerated, and the battery life is also shortened.

Second is the low energy density. It occupies a large area, has a large weight, and has high requirements for load bearing on the floor. These problems are becoming more and more prominent as the data transmission volume of communication equipment continues to increase.

Once again, it is easy to be stolen. Lead-acid batteries can be used in a variety of applications after being stolen, and the lead content is high and the recycling is convenient. These are the reasons for the theft of lead-acid batteries.

Finally, it is an environmental issue. “Lead pollution is mainly found in the manufacture and recycling of lead storage batteries. One of the processes is to melt lead. The melting and recycling process is prone to pollution,” said Perry Gottesfeld, president of the Professional Knowledge International Association. In fact, for the lead battery industry, it is the recycling process that is more likely to cause pollution than the production process.

Therefore, there is an urgent need to excel in performance, and the overall cost does not increase too much energy storage to replace the traditional lead-acid battery. At this time, lithium-ion batteries have entered people's attention.

Lithium-ion batteries have sprung up, and the potential is huge.

Lithium-ion batteries have not appeared in recent years. It has been in commercial use for more than 20 years in the mobile phone field, but lithium batteries are a new force in the communication site as a backup power source. At this stage, most of the lithium batteries used in the field of communication backup power are lithium iron phosphate batteries, and a small part are ternary lithium batteries.

From the perspective of environmental protection, lithium batteries have a natural advantage. The materials used in lithium batteries do not contain polluting metals, such as cadmium, lead, mercury and other harmful heavy metals. Lithium batteries have no pollutants during production and use, which guarantees the health of the human body. It will not cause pollution of water and soil.

In terms of electrical performance, lithium batteries have surpassed lead-acid batteries. Lithium batteries have excellent cycle life, high temperature characteristics, charge and discharge rate performance and energy density, which are far superior to lead-acid batteries. For example, the lithium battery of the same capacity has a volume and weight of one-half to one-third of that of a lead-acid battery, and can be arbitrarily connected. There is no special requirement for building space, load-bearing, etc., which greatly reduces the cost of site rental. . In addition, the excellent high temperature characteristics of the lithium battery can reduce the air conditioning configuration and power consumption of the base station. After the lithium battery is stolen, the recycling value is not large. Because of the existence of the battery management system, it cannot be used directly, which reduces the risk of theft of the backup power supply.

The same is the characteristics of lithium-ion batteries, ternary lithium batteries and lithium iron phosphate batteries. The cycle life of the ternary lithium battery is between the lead-acid battery and the lithium iron phosphate battery, but the float charge life is much better than the lithium iron phosphate battery, and the energy density is more than 50% higher than the lithium iron phosphate battery, and the cost is also lower than lithium iron phosphate battery. The flexible choice of lithium iron phosphate battery and ternary lithium battery will make the lithium battery backup power supply more widely used in the communication industry.

Currently, the one-time cost of lithium batteries is still high, but lithium batteries are not higher than lead-acid batteries in terms of total cost of ownership (TCO). Although the price is 2 to 4 times higher than that of ordinary lead-acid batteries, the TCO in the life cycle of lithium batteries is even lower than that of lead-acid batteries due to its long life, low maintenance and replacement costs. In the future, with the development of electric vehicles and energy storage industry, lithium battery applications will continue to scale, prices will become lower and lower, and more and more competitive.

Differentiated scenes make the advantages of lithium batteries more prominent

The power grid difference area is used as a backup power source, which takes advantage of its long cycle life. Lead-acid batteries are characterized by long float life and short cycle life. In short, the less they are used, the better. However, the grid environment in many countries and regions is not good, and the power outage time exceeds 2 hours per day. Frequent recycling will lead to a rapid decline in the life of lead-acid batteries, and lithium batteries with high cycle life are suitable for use in such environments.

It is applied to wall-mounted power supplies and pole-mounted power supplies, highlighting its high energy density. Lead-acid batteries have the disadvantages of large area, heavy weight and high load-bearing requirements, and it is increasingly difficult to meet the requirements of small space scenes. The lithium battery has an energy density of 2 to 4 times that of a lead-acid battery, and is particularly suitable for use in the above environment.

It is used in a short-time standby UPS or communication power supply to give a good discharge rate. In some scenarios where the oil machine is used for emergency power supply, the backup power supply of the UPS or communication power supply needs 5 to 10 minutes of backup time to back up the data and switch to the emergency power supply of the oil machine. In this case, only the battery needs to be 5 to 10 A certain output power is guaranteed within minutes. Lithium batteries can output more than 90% of rated capacity in 10 minutes, while lead-acid batteries can discharge up to 30% of rated capacity in 10 minutes. Lithium batteries can be configured with much less capacity than lead-acid batteries to meet short-term requirements. The requirements for backup power save space and cost.

High-performance lithium battery, need to cooperate with excellent battery management system

Lithium batteries for communication energy storage need to be equipped with an excellent battery management system for truly safe and stable use. The theoretical characteristics of lithium batteries determine that they are sensitive to overcharge and overdischarge. Due to the short development time, the industry's research on its consistency, stability, large-scale series-parallel, temperature control and other issues is still not deep, so it needs to focus. In the development of battery management systems, lithium batteries can be used more effectively and safely.

"The general battery management system can only guarantee the basic safety of the lithium battery pack. A good battery management system can extend the service life of the lithium battery pack, find hidden dangers of safety and performance, and reduce the failure rate." Energy storage expert Mr. Ma Xiangmin said, " The Huawei Network Energy Product Line and the 2012 Lab have conducted in-depth research on the SOH (health status) and fault warning settings of lithium battery packs through large data mining and adaptive state assessment of lithium battery systems, and rely on power supply and The management software advantage of network management, designing a battery management system with core competitiveness has been applied in many communication products."

The application of Pakistan is a good case. In Pakistan, the grid in some areas is very unstable, with frequent power outages every day and long blackouts. According to statistics, the total cost of fuel power generation per year for 5,886 sites is $80 million. “Lead-acid batteries are used in this area, not only because of frequent recycling, but also because of the early termination of life, and each time the utility power is restored, the battery is often not fully charged and needs to be discharged, resulting in the battery being quickly de-energized, and the oil machine needs to be started power generation.” Ma Xiangmin said, “Huawei has provided Pakistani operators with a lithium battery as a backup power supply solution. The battery management system flexibly adjusts the battery charging current so that the lithium battery backup power can be fully charged after the utility power is restored. Ensure the backup time; discover and locate the faulty battery in time through the battery SOH detection and fault warning function, reduce the risk of the station; improve the cycle life of the lithium battery through the battery sleep function, greatly reduce the frequency of use of the oil machine. Huawei in Pakistan More than 1,000 sites have been rebuilt, saving $22.1 million in fuel per year and recovering input costs in 1.5 years."

Summary

The backup power supply based on lithium battery can be widely used in indoor and blind area coverage, second and third types of mains areas, short-time backup power, etc., which have high requirements on power weight, volume, cycle life and magnification. In the era of big data, scenes with limited space such as shared stations and expansion of central computer rooms are gradually requiring the participation of lithium battery backup power. In the future, with the large-scale production of energy storage lithium batteries, the cost will continue to decline, and lithium batteries will play an increasingly important role in the field of communication backup power.

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