A Li-dual carbon composite as stable anode material for Li batteries

Tremendous amount of effort has been dedicated to revisit metallic lithium as anode material for high-energy-density lithium batteries in recent years. Although some progresses have been achieved within this field, development of lithium metal anode material with higher specific capacity and better stability is still urgently needed considering the practical application of batteries. Here we report a Li-carbon nanotube-acetylene black (Li-CNT-AB) composite microsphere anode material by a simple and scalable method. The lithiophilic CNTs were used to construct a porous sphere framework, while the lithiophilic AB particles well distributed in the sphere framework were used to utilize the pore space of the sphere thus increasing the lithium content of the composite, and to act as a lithium deposition promoter during battery cycling because AB has lower lithium nucleation barrier. As a result, the Li-CNT-AB composite exhibits a specific capacity as high as 2800 mA h g(-1) and a life span of similar to 700 cycles can be achieved when it was cycled with a commercial LiFePO4 (LFP) cathode at 0.5 C (1.25 mA cm(-2)) in an ether-based electrolyte with the capacity ratio of cathode to anode being 1: 8, corresponding to a high Coulombic efficiency (CE) of similar to 98.7%. Furthermore, it was observed that there is no lithium dendrite formation and negligible volume change on the Li-CNT-AB during electrochemical cycling.