Sharma, Neeraj Guo, Xianwei Du, Guodong Guo, Zaiping Wang, Jiazhou Wang, Zhaoxiang Peterson, Vanessa K. Direct Evidence of Concurrent Solid-Solution and Two-Phase Reactions and the Nonequilibrium Structural Evolution of LiFePO<sub>4</sub> Lithium-ion batteries power many portable devices and in the future are likely to play a significant role in sustainable-energy systems for transportation and the electrical grid. LiFePO<sub>4</sub> is a candidate cathode material for second-generation lithium-ion batteries, bringing a high rate capability to this technology. LiFePO<sub>4</sub> functions as a cathode where delithiation occurs via either a solid-solution or a two-phase mechanism, the pathway taken being influenced by sample preparation and electrochemical conditions. The details of the delithiation pathway and the relationship between the two-phase and solid-solution reactions remain controversial. Here we report, using real-time in situ neutron powder diffraction, the simultaneous occurrence of solid-solution and two-phase reactions after deep discharge in nonequilibrium conditions. This work is an example of the experimental investigation of nonequilibrium states in a commercially available LiFePO<sub>4</sub> cathode and reveals the concurrent occurrence of and transition between the solid-solution and two-phase reactions. occurrence;candidate cathode material;sample preparation;Direct Evidence;LiFePO 4Lithium batteries power;rate capability;Nonequilibrium Structural Evolution;nonequilibrium states;LiFePO 4;electrochemical conditions;neutron powder diffraction;LiFePO 4 cathode;LiFePO 4 functions;delithiation pathway;nonequilibrium conditions 2012-05-09
    https://acs.figshare.com/articles/journal_contribution/Direct_Evidence_of_Concurrent_Solid_Solution_and_Two_Phase_Reactions_and_the_Nonequilibrium_Structural_Evolution_of_LiFePO_sub_4_sub_/2523754
10.1021/ja301187u.s001