The structural phase transitions of the lead-free relaxor ferroelectric Bi1/2Na1/2TiO3 (BNT) have been investigated using various methods, but the understanding of the lattice dynamics is still very limited. Solid solutions like (1-x)Bi1/2Na1/2TiO3-xBaTiO3 (BNT-100xBT, BNT-BT) show particularly promising ferroelectric properties near the morphotropic phase boundary around BNT-6BT and should replace some lead-containing ferroelectric materials for environmental and health reasons in the medium term. However, a better understanding of the lattice dynamics is crucial for the determination of the influence of dopants like BaTiO3 on the crystal lattice of BNT. This influence needs to be understood before a systematic search for improvements in the ferroelectric and ageing properties can be conducted. Consequently, we propose to measure the phonon dispersion of BNT, BNT-4BT and BNT-12BT in the [100] direction. This pilot experiment, which is part of the PhD work of Florian Pforr, would also help us estimate the potential value of further inelastic neutron scattering measurements on BNT-BT at elevated temperature.