Nanostructured pyramidal shape ruthenium oxide (Ru⁺⁴O₂) was studied electrochemically using cyclic voltammetry (CV) and cyclic charge-discharge (CCD) experiments at five different cut-off voltages (1.5, 1.0, 0.80, 0.4, and 0.1 V) versus Li/Li⁺. CCD experiments performed at cut off voltages of 1.5 V and 1.0 V showed a plateau at approximately 2.1 V that corresponds to 100 and 350 mAh g^-1, respectively, with no significant formation of solid electrolyte interface (SEI). CV experiments performed in the same voltage range showed a reduction and an oxidation peak at 2.1 and 2.5 V, respectively, that corroborated the CCD experiments. At cut off voltages below 1.0 V, the CV showed two peaks current at 1.0 V (Ru⁰/Li₂O) and 0.6 V (SEI) during the first forward potential sweep. The SEI disappeared during the second cycle and beyond. On the other hand, during the reverse potential sweep two peak currents are observed at 1.2 V and 2.7 V. The latter represents the oxidation of Ru⁰ to Ru⁺⁴ and the former is assigned to the decomposition of the SEI. The CCD experiments revealed a total capacity of approximately 1200 mAh g^-1 (~6 Li⁺ per mol of Ru⁺⁴O₂). However, the expected capacity is 806 mAh g^-1 (4 Li⁺ per mol of Ru⁺⁴O₂) as described by the conversion reaction of lithium with Ru⁺⁴O₂ (Ru⁺⁴O₂ + 4Li⁺+4e^- <-->Ru⁰ + 2Li₂O). Therefore, there is an excess capacity of ~600 mAh g^-1. To understand the source of the excess capacity, CCD experiments were performed in the range of 2.0 to 0.1 V vs. Li/Li⁺ which revealed that the material is behaving as a pseudo-capacitor. The calculated capacity in this range is only 90 mAh g^-1. This value is too small to account for the excess capacity.