Measurement of voltage noise in chemical batteries

Ultra low noise voltage sources are often required in measurement systems and other applications. Common voltage regulators have performed inadequately in some applications. As an alternative, battery cells have been used. Of the various types, Hg cells have been credited with the best performance. However, actual values for the voltage noise in batteries have not, to our knowledge, been reported. In this paper a measurement system capable of measuring voltage noise below -200 dBV/Hz is discussed and its ability to characterize experimentally high performance voltage references is explored. The results of such measurements on common batteries are presented, and potential applications are considered