creating the EC binder. The graphene powder is then dispersed in this EC binder *via* three-roll mill to ascertain the maximum loading of graphene before the ink becomes unprintable. We find that the maximum amount of graphene that can be introduced to the EC binder before the viscosity of the ink exceeds the upper limit of the screen printable viscosity range ($\sim$2-10 Pa s) is $\sim$23 wt.%; Fig. \[panel1\]c. In addition, rheological characterisation is also carried out on the ink at this stage to ensure it has the necessary shear-thinning properties as depicted in \[panel1\]d for screen printing. To further characterise shear thinning behaviour, the measured viscosity and shear rate were plotted in a log-log plot to observe power law behaviour; Fig. \[panel1\]e. The power law model, also known as the Ostwald de Waele model is a rheological model that can be applied to shear thinning fluids to observe their behaviour under shear [@Bjrn2012]. The model can be expressed mathematically using the following equation:

$$\eta = K  ^* \dot{\gamma}^{n-1}
    \label{powerlaw}$$

where $K$ is the consistency factor and $n$ is the power law index; $n <$1 represents shear thinning behaviour, $n$ = 1 represents Newtonian behaviour and $n >$1 = shear 