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<jats:p> Lithium-oxygen (Li-O <jats:sub>2</jats:sub> ) batteries cycle reversibly with lithium iodide (LiI) additives in dimethoxyethane (DME) to form lithium hydroxide (LiOH). Viswanathan <jats:italic>et al.</jats:italic> argue that because the standard redox potential of the four-electron (e <jats:sup>−</jats:sup> ) reaction, 4OH <jats:sup>–</jats:sup> ↔ 2H <jats:sub>2</jats:sub> O + O <jats:sub>2</jats:sub> + 4 <jats:italic>e</jats:italic> <jats:sup>–</jats:sup> , is at 3.34 V versus Li <jats:sup>+</jats:sup> /Li, LiOH cannot be removed by the triiodide ion (I <jats:sub>3</jats:sub> <jats:sup>–</jats:sup> ). However, under nonaqueous conditions, this reaction will occur at a different potential. LiOH also reacts chemically with I <jats:sub>3</jats:sub> <jats:sup>–</jats:sup> to form IO <jats:sub>3</jats:sub> <jats:sup>–</jats:sup> , further studies being required to determine the relative rates of the two reactions on electrochemical charge. </jats:p>

<jats:p> Liu <jats:italic>et al</jats:italic> . (Research Article, 30 October 2015, p. 530) described a lithium-oxygen (Li-O <jats:sub>2</jats:sub> ) battery based on lithium iodide (LiI)–assisted lithium hydroxide (LiOH) formation and decomposition. We argue that LiOH cannot be oxidized by triiodide (I <jats:sub>3</jats:sub> <jats:sup>–</jats:sup> ). The charge capacity is from the oxidation of I <jats:sup>–</jats:sup> instead of LiOH. The limited-capacity cycling test is misleading when the electrolyte contributes considerable parasitic reaction capacity. </jats:p>

<jats:p> We described a lithium-oxygen (Li-O <jats:sub>2</jats:sub> ) battery comprising a graphene electrode, a dimethoxyethane-based electrolyte, and H <jats:sub>2</jats:sub> O and lithium iodide (LiI) additives, lithium hydroxide (LiOH) being the predominant discharge product. We demonstrate, in contrast to the work of Shen <jats:italic>et al.</jats:italic> , that the chemical reactivity between LiOH and the triiodide ion (I <jats:sub>3</jats:sub> <jats:sup>–</jats:sup> ) to form IO <jats:sub>3</jats:sub> <jats:sup>–</jats:sup> indicates that LiOH can be removed on charging; the electrodes do not clog, even after multiple cycles, confirming that solid products are reversibly removed. </jats:p>

<jats:p> Based on a simple thermodynamic analysis, we show that iodide-mediated electrochemical decomposition of lithium hydroxide (LiOH) likely occurs through a different mechanism than that proposed by Liu <jats:italic>et al</jats:italic> . (Research Article, 30 October 2015, p. 530). The mismatch in thermodynamic potentials for iodide/triiodide (I <jats:sup>−</jats:sup> /I <jats:sub>3</jats:sub> <jats:sup>−</jats:sup> ) redox and O <jats:sub>2</jats:sub> evolution from LiOH implies a different active iodine/oxygen electrochemistry on battery charge. It is therefore possible that the system described in Liu <jats:italic>et al</jats:italic> . may not form the basis for a rechargeable lithium-oxygen (Li-O <jats:sub>2</jats:sub> ) battery. </jats:p>