Materials Research Bulletin, Vol.94, 328-334, 2017
High electrochemical performance bendable Li secondary batteries based on a three-dimensional metal foam-type current collector
Bendable lithium secondary batteries have many limitations, including low electrochemical performances and poor mechanical flexibility. Here, we bendable pouch batteries are fabricated using LiFePO4/C as the active material and three-dimensional Nickel-Chroinium alloy metal foam as the current collector of positive electrodes. The advantages of using the three-dimensional structured metal foam include a high surface area for the redox reaction, high electronic conductivity, and short diffusion length for the lithium ion. We demonstrate the use of bendable lithium secondary batteries with a high areal capacity of about 3.5 mAh cm(-2) at C-rate of 0.2, a high capacity retention rate in cycle life behavior, and a greatly low charge transfer resistance of around 6-8 Omega. Moreover, our bendable pouch batteries can be repeatedly bent to radii of 12.5 and 2.5 mm for several hundred times without fractures in the electrode and capacity fading. (C) 2017 Elsevier Ltd. All rights reserved.
Keywords:Lithium secondary battery;Bendable battery;Three-dimensional structured current;collector;Nickel-chromium alloy metal foam;Areal capacity