A study, undertaken by the Institute of Metal Research and the Institute of Physics, both affiliated to the Chinese Academy of Sciences, has achieved breakthroughs in preparing carbon nanotubes/fibers that can be used to serve as the cathodes for large volume and high power lithium cells. Aiming at raising cells?¯ dynamic and cycling performance, researchers developed carbon nanotubes/fibers that can store lithium either in graphite layers or in nanoholes. They worked out the cathodes made of chrome and lithium oxides high in volume and low in cost. The study also resulted in the cathode materials with dumpling structures, which offers a high volume and fine cycling performance. The primary composite cathode material at a mixed nanometer-micron level, also derived from the study, utilizes the nanoscale effect, in an attempt to reduce the cost. The cathode material developed has reached a volume of 600 mAh/g, or 1.8 times that of the cathode materials in current commercial applications, with volume attenuation less than 20% after 500 cycles. A high power 35-AH cell made of nano cathode materials can offer a power density as high as 1500W/kg. The cells of the specifications 18650 and 3450 reach a power density of 238Wh/kg, with fine cycling performance. The research findings have resulted in 11 invention patent applications or grants, of which 1 is a PCT application. 

In the course of developing the new materials, the enterprises that are involved in the study have embarked on commercial applications of the high performance cathode materials, and established a production line with annual capacity of 110 tons. The production line produces 20 tons of carbon nanotubes/fibers a year, with additional capacity for 60 tons of hard carbon balls with nanoholes, and 30 tons of cathode materials with dumpling structures.