T-shape cells fed with polarized hydrogen or deuterium atoms were used at several storage rings like COSY, DESY or IUCF to serve as polarized internal targets. To avoid polarization losses of the stored atoms, e.g. by recombination into molecules, different solutions are found for the surface materials. For example, aluminum at its ceramic monolayer of aluminum oxide on top, Teflon or a water ice surface are successfully used. But these surface materials are not allowed for the coming polarized storage cell target at LHCb for vacuum reasons or possible beam problems. The only allowed material so far would be an amorphous carbon coating, but here exists no experience about possible depolarization effects. Corresponding experiments to investigate the recombination rate of polarized hydrogen atoms and the polarization preservation are under way at the research center in Jülich.