People walk past CATL's headquarters in Ningde, Fujian province, on March 14, 2023. [Photo by Li Fusheng/chinadaily.com.cn]

Contemporary Amperex Technology Co, the world's largest EV battery maker, debuted on Tuesday what it claimed to be the world's first energy storage system with "ageless battery" over a period of five years.

The move marks a step forward in terms of longevity and scalability of energy storage and intensifies the competition in the sector.

The system, called Tianheng, is capable of mass production with zero attenuation in the first five years.

The system can generate a high energy of 6.25 megawatt-hours within a standard 20-foot shipping container. This upgrades the energy density by 30 percent per unit area, the company said.

It added that it is also embedded with a lithium iron phosphate battery that has ultra-high energy density with 430 watt-hours per liter.