Light hydrogen atoms are resolvable with neutrons; however, the massive incoherent background inhibits the diffraction quality. To improve the signal, isotope treatment by deuteration becomes a prerequisite for a successful crystallographic understanding of hydrogen-containing materials by neutron diffraction. Thanks to the low-background and high-resolution time-of-flight neutron diffractometer, this work demonstrates a direct and successful measurement of high-quality neutron diffraction patterns of H2VOPO4 powders, a precursor of a high-capacity alkali-ion battery cathode. The Rietveld refinement identifies the hydrogen coordinates, occupancy, and thermal parameters in the H2VOPO4 lattice. The result highlights the unique capability of neutron diffraction for the structure characterization of hydrogen-containing materials, potentially without requiring costly and possibly artifact-inducing deuteration for neutron diffraction.