Table 3.

Predicted Nernst slopes and observed Nernst slopes of LiMn₂O₄.

Reaction[a]	E 0,NHE [V][b]	ν NHE [mV pH−1][c,d]	ν RHE [mV pH−1][c,e]
4 OH−↔O2+4 e−+2 H2O	0.401	−59	0
MnO2+4 OH−↔MnO4 ‐+3 e−+2 H2O	0.595	−79	−20
MnO2+4 OH−↔MnO4 2−+2 e−+2 H2O	0.600	−118	−59
MnO2+2 H2O↔HMnO4 −+2 e−+3 H+	2.09	−39	20
LiMn2O4↔Li++Mn2O4	≈0.9[f]	0	59
observed for LiMn2O4 (0.74–0.81 V versus NHE)	n/a	−63(1)	−2(1)
observed for LiMn2O4 (<0.72 V versus NHE)	n/a	−41(1)	20(1)

[a] Based on Ref. 77. [b] Equilibrium potential on the NHE scale.77 [c] Uncertainties (1σ) of the fit to a constant are indicated. [d] Nernst slope of the disk on the NHE scale. [e] Nernst slope of the disk on the RHE scale. [f] In aqueous brine against Ag counter;76 the estimated experimental onset of delithiation from LiMn₂O₄ is ≈0.7 V versus NHE (≈1.5 V versus RHE).