This paper presents a battery test bench for investigation of cell parameters for a battery management system. The test bench is used to examine the cell parameters as open circuit voltage (UOC), cell resistance (Ri) and the cell capacity (C). The results were analyzed to find dependency to the state variables state of charge (SoC), state of health (SoH) and state of function (SoF). For this paper, a zinc-air battery with 50 Ah capacity is analyzed with the test bench. The analyzed cell shows a function of cell resistance to state of charge.