Patent ID: 8242746

Claim:
Method for measuring cell voltages of accumulator cells in a plurality of series-connected accumulator cells with a common reference potential, comprising a number of series-connected measuring resistors matching the number of cells to be measured, as well as a number of switches between the measuring resistors and the cells by means of which, upon closing, one of the measuring resistors is connectable in parallel to one of the cells, respectively, comprising the steps: closing the switch connected to a first terminal of a cell to be measured as well as a further switch at a terminal of a cell that, in comparison to the cell to be measured, has a higher absolute voltage relative to the reference potential, and optionally opening all other switches; determining and saving the voltage drop at the first terminal relative to the reference potential; opening the switch that is connected to the first terminal of the cell to be measured and closing the switch that is connected to the second terminal of the cell to be measured; determining and saving the voltage drop at the second terminal relative to the reference potential; determining the cell voltage by calculating the difference of the voltages determined across the two terminals.