Li4Ti5O12 typically shows a flat charge/discharge curve, which usually leads to difficulty in the voltage-based state of charge (SOC) estimation. In this study, a facile quench-assisted solid-state method is used to prepare a highly crystalline binary Li4Ti5O12-Li2Ti3O7 nanocomposite. While Li4Ti5O12 exhibits a sudden voltage rise/drop near the end of its charge/discharge curve, this binary nanocomposite has a tunable sloped voltage profile. The nanocomposite exhibits a unique lamellar morphology consisting of interconnected nanograins of approximate to 20 nm size with a hierarchical nanoporous structure, contributing to an enhanced rate capability with a capacity of 128 mA h g1 at a high C-rate of 10 C, and excellent cycling stability.