fig4

Figure 4. Gas-evolution behavior and full-cell lithium-compensation performance. (A-D) Electrochemical profiles and corresponding O₂ and CO₂ evolution rates of (A) LFO, (B) LFO-24h, (C) LFO-BF, and (D) LFO-BF-24h during the first charge-discharge cycle at 50 mA g^-1, as measured by DEMS; (E) Initial charge/discharge profiles of NMC//graphite full cells with and without 4 wt% LFO-BF at 30 mA g^-1; (F) Cycling performance and Coulombic efficiency of NMC//graphite full cells with and without 4 wt% LFO-BF, the black arrows indicating the corresponding y-axes: the upper arrow for Coulombic efficiency (right axis) and the lower arrow for capacity (left axis). DEMS: Differential electrochemical mass spectrometer; NMC: lithium nickel manganese cobalt oxide; LFO-BF: NH₄BF₄-treated Li₅FeO₄.