Since 1859, French physicist Jaston Planter has invented rechargeable lead-acid batteries, and has come to nickel-cadmium batteries, nickel-hydrogen batteries, lithium batteries and fuel cells. The emergence and application of new materials have made battery performance. Great progress has been made. Every time the battery positive or negative material or electrolyte is updated and improved, the overall performance of the battery will be improved. The development direction of the battery has been pursuing high capacity, high power, high stability, low pollution, and long service life. With the continuous improvement of performance, its application field is also expanding.
Miniaturization of electric equipment to generate new batteries
According to the nature of the electrolyte, the battery can be divided into two types: an acid battery and an alkaline battery. The acid battery is mainly lead-acid battery, the electrode is lead, and the electrolyte is sulfuric acid solution. Lead-acid battery has the advantages of large capacity, high reliability, superior current discharge performance, wide application temperature range and high cost performance. It is the most widely used secondary battery, accounting for more than 70% of the secondary battery market share. Used in backup power, electric bicycles and car starters. Alkaline batteries mainly include cadmium-nickel batteries, iron-nickel batteries, etc., and the electrolytes thereof are sodium hydroxide and potassium hydroxide. Mainly used as DC power supply for electronic equipment such as automation control, instrumentation and so on.
With the continuous development of wireless technology, power-consuming equipment tends to be highly integrated, intelligent, light and miniaturized, and the traditional battery gradually presents a disadvantage of large volume and harsh environmental requirements, and the specific energy and work of the backup power supply. The temperature range and so on put forward higher requirements. In recent years, the battery family has emerged as a new type of battery with many advantages. Lithium iron phosphate battery and fuel cell are typical representatives of new batteries.
Self-powered power supply
Indoor distribution system power supply refers to an independent power supply that supplies power for indoor distribution system power equipment (BBU, RRU, and monitoring equipment).
Self-provided backup power supplies generally use self-provided diesel generator sets, battery packs, uninterruptible power supply units (UPS), and emergency power supply units (EPS). Since the time required for the power supply to interrupt the power supply is different, the choice of the self-supplied backup power source is also different.
Inverter power supply backup power supply: The original China Unicom CDMA network uses a large number of inverter power supply backup power supply. The long-term operation results prove that the inverter power supply backup scheme adopted has the disadvantages of low reliability and high maintenance frequency. If the inverter power supply backup scheme is adopted, the inverter power supply equipment with redundant modularization can be considered, thereby improving the reliability of the overall power supply and reducing the cost of operation and maintenance.
UPS power supply: The UPS is a power protection device that contains an energy storage device, with the inverter as the main component and the regulated frequency output. The advantage of the UPS power supply scheme is that it has a relatively stable backup time and is easy to implement AC power supply over long distances.
The disadvantages of UPS are also obvious. If the UPS equipment is placed in the user-side equipment (such as shaft, elevator or even the basement) where the operating environment is relatively harsh, the operating environment is poor and the power supply pollution will cause the UPS working life to be greatly shortened; the small UPS battery The management is weak, which will reduce the service life of the battery. In order to reduce the size of the equipment, some rack-type equipments use forced air cooling to increase the output power density. The noise during operation is large, which is easy to cause complaints from the owners, to build stations and future. Operation and maintenance work has increased the difficulty.
Wall-mounted switching power supply: the use of small UPS can solve the backup power supply problem, but its output efficiency is usually only about 80%, the entire power supply link by the UPS through AC->DC->AC, the conversion process, energy efficiency loss, about 20% The energy of the energy becomes consumed in vain; if the small UPS considers redundant backup, it can only use dual or multi-machine parallel redundancy, which cannot achieve modular backup redundancy, and the switching power supply has modular redundant backup and conversion efficiency. High features. At the same time, the switching power supply can realize accurate floating charge control and temperature compensation functions, which can effectively provide comprehensive management functions of the battery.