Journal of Power Sources, Vol.196, No.16, 6982-6986, 2011
High performance Si/C@CNF composite anode for solid-polymer lithium-ion batteries
The electrochemical performance of a composite of nano-Si powder and a pyrolytic carbon of polyvinyl chloride (PVC) with carbon nanofiber (CNF) was examined as an anode for solid-polymer lithium-ion batteries. Nano-Si powder was firstly coated with carbon by pyrolysis of PVC and then mixed with CNF (referred to as Si/C@CNF) using a rotation mixer. The composite exhibited good cycling performance, but suffered from a large irreversible capacity loss of which the retention was less than 60%. In order to reduce the loss, a thin lithium sheet was attached to the Si/C@CNF electrode surface as a reducing agent. The irreversible capacity of the first cycle was lowered to as much as 0 mAh g(-1) and after the third cycle, the lithium insertion and extraction efficiency was almost 100%. A reversible capacity of more than 1000 mAh g(-1) was still maintained after 40 cycles. (C) 2010 Elsevier B.V. All rights reserved.