With the insights gained on the decomposition of dimer, we can now explain our earlier observation where lowering the discharge cutoff potential down to 0.3 V adversely affects the DHAQ recovery efficiency (Figure ). Conversion of DHA to DHAQ includes two electrochemical oxidation reactions as depicted in Scheme 2: DHA  0.5 Dimer and then 0.5 Dimer  DHAQ. Between these two, the first reaction proceeds at a higher cell voltage (e.g. a less positive oxidation potential for the negolyte) than the second: as shown in Figure , the first and second reactions are initiated at cell voltages of about 0.9 V and 0.0 V, respectively, and proceed to completion as the cell voltage is lowered further, increasing the driving force for the reactions. Lowering the cycling discharge cutoff voltage to 0.3 V not only oxidizes the DHAQ 4-(reduced form of DHAQ), but it also oxidizes any DHA formed during the disproportionation reaction to the dimer. Nevertheless, the cell voltage is not low enough to proceed to the oxidation of the dimer; this causes the accumulation of dimer, which is unstable, in the electrolyte. The dimer undergoes a decomposition reaction until the cell voltage is lowered enough during the deep-discharge step to oxidize the remaining dimer.