Charge distributions of lithium ions after passage through different gas and foil strippers are measured in the energy range between 0.5 and 2 MeV. The ratios of the equilibrated beam components with charge i and k (Fi∞/Fk∞) were found to obey simple power-laws. A density effect of about 15% was observed. Measured charge distributions are compared with calculated. Relatively good agreement could only be reached with the method of DMITRIEV using shell-dependent probability functions of HECKMAN. An empirical expression for the average equilibrium charge q as function of the particle energy is given and discussed.