Investigations about the Use and the Degradation Mechanism of LiNi0.5Mn1.5O4 in a High Power LIC

The manuscript reports the performance of a hybrid device containing the spinel positive electrode material LiNi0.5Mn1.5O4 (LNMO). The LNMO samples were synthesized via a sol-gel process with a post thermal treatment at 1000 degrees C and then combined against an activated carbon negative electrode. The obtained device shows excellent cycling stability as well as good electrochemical performance at a current rate of 600 mA g(-1) (corresponds to 10C for LNMO) in a cell voltage range of 3.3 V which is significantly high voltage among reported lithium intercalation cathode-based lithium-ion capacitors (LIC). With constant current cycling at 600 mA g(-1), the LIC delivered a promising capacity retention of 89% even after 4,000 cycles with average specific energy and power of about similar to 50 Wh kg(-1) and similar to 1100 W kg(-1). (C) 2014 The Electrochemical Society. All rights reserved.