The article includes a picture showing a lithium-ion battery made with a novel SnS2 semi-filled carbon nanotube anode material driving an LED matrix that "lights up" the emblem of Dalian University of Technology.
After years of research, the Energy Materials and Devices Laboratory has made a breakthrough in addressing the bottleneck problem of capacity decay and low conductivity caused by severe volume expansion of lithium-ion battery electrode materials during charge and discharge. They have achieved the fabrication of carbon-confined core-shell structured anode materials, solving a key challenge in lithium-ion battery capacity decay. Based on this, the laboratory has developed a novel SnS2 semi-filled carbon nanotube lithium-ion battery anode material. This anode material exhibits an "unconventional" capacity reversal characteristic during charge-discharge cycling. At a current density of 0.3 Ag⁻¹, the initial discharge capacity is 1258 mAh g⁻¹. After 470 cycles, the capacity gradually increases to 2733 mAh g⁻¹, more than double the initial capacity, meaning the battery's lifespan increases with use.
Through a series of microstructural characterizations, the laboratory revealed that the increased capacity originates from the interface of fragmented SnS2 grains. These fragmented grains are encapsulated and constrained by carbon nanotubes, maintaining a good conductive network – a phenomenon the laboratory termed the "pocket effect." Lithium-ion batteries assembled with this novel anode material exhibit excellent lithium storage performance and safety, achieving 3-7 times the capacity of currently commercialized lithium-ion batteries (using carbon-based anode materials), and operate stably at 0-60°C.
This research was conducted under the guidance of Professor Huang Hao and completed by doctoral student Jin Xiaozhe (first author) and others. The research was jointly funded by the National Natural Science Foundation of China and the Fundamental Research Funds for the Central Universities, and received strong support from Professor Zhao Jijun of the School of Physics, Professor Cao Guozhong of the University of Washington, and other researchers. In recent years, the Energy Materials and Devices Laboratory of the School of Materials Science and Engineering has focused on major national needs in the energy field, exploring key technologies such as large-scale preparation of nanomaterials, control of nanostructures, and high-density electrode energy storage, providing a theoretical foundation and technical support for improving the engineering application of nanomaterials and devices.
