Free-standing and flexible LiMnTiO₄/carbon nanotube cathodes for high performance lithium ion batteries

A flexible, free-standing, and light-weight LiMnTiO₄/MWCNT electrode has been prepared by vacuum filtration method for the first time. The as-prepared flexible LiMnTiO₄/MWCNT electrode possesses a three-dimensional braiding structure in which LiMnTiO₄ particles are well embedded in the twining CNT networks. The novel LiMnTiO₄/MWCNT electrodes show tensile strength of 1.34 MPa and 2.04 MPa, when the percentages of MWCNTs reach to 30% and 50%, respectively. This novel flexible electrode exhibits a superior electrochemical property, especially at rate capability and cycling stability. The LiMnTiO₄/MWCNT electrode can deliver capacity of 161 mAh g^-1 (86.4% retention) after 50 cycles at 0.5C rate. Since the high conductivity from MWCNT networks, the LiMnTiO₄/MWCNT electrode can still maintain a capacity of 77 mAh g^-1 at 5C rate, which is much higher than that of the conventional electrode fabricated by slurry casting method on Al foil. The features of free-standing, light-weight, and excellent electrochemical performance indicate the potential of using the LiMnTiO₄/MWCNT cathode in new-generation flexible lithium ion batteries.