Figure 5. Cyclic voltammetry. ( a ) PDHA CHEM - potential range: 1.8 to 3.2 V vs. Li/Li + , rate: 0.1 mV s − 1 . ( b ) PDHA CHEM reported in ref. 15 - potential range: 1.8 to 3.2 V vs. Li/Li + , rate: 1 mV s − 1 . ( c ) PDHA E-CHEM -