Pressure Induced Superconductivity of BaLi$_{4}$

We studied the pressure-induced superconductivity of BaLi$_{4}$~up to 53~GPa by means of electrical resistivity in a diamond anvil cell. Superconductivity in BaLi$_{4}$~is first observed at a pressure of 5.4~GPa with a superconducting critical temperature ($T_{\mathrm{c}})$ of 4.5~K. Below 2~GPa, superconductivity is not observed above the minimum temperature achievable in the current study, 2~K. Between 5.4 and 12~GPa, the~$T_{\mathrm{c}}$~increases steeply to its maximum value of 7~K. Above 12~GPa, the pressure dependence of~$T_{\mathrm{c}}$ is complex and the sign of d$T_{\mathrm{c}}$/d$P$~changes several times in going up to the maximum pressure studied, of 53~GPa.