Effects of Connections and Input Impedance

Connections to electrochemical cells are usually made via a potentiostat/galvanos-tat. There are particularly critical points on the cell where great care needs to be taken in the method of connection. Usually the counter electrode (CE) is where the stimulus waveform is applied to the cell and this is not a particularly critical part of the system. However, the points where voltage and current are measured are vital to the accuracy of the results. 

For very sensitive measurements on very low impedance (or very high impedance) cells it may be necessary to shield the cell from external interference using a Faraday cage which is connected to the instrument ground and it may also be necessary to take particular care regarding the placement of cables to avoid electrical interference and cross-talk between cables. 

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