In this work, we aim to asses the effect of the DFT+U correction as implemented in the widely used VASP code when applied to extended p-states as the ones present in Li 2 O 2 . For this, we vary the U parameter between 0 and 16 eV in order to observe the effect of the Hubbard correction on the crystalline and electronic structure for Li 2 O 2 bulk and its more stable surfaces.