  Recently, a disruptive idea was reported about the discovery of a new type of
battery named Liquid Displacement Battery (LDB) comprising liquid metal
electrodes and molten salt electrolyte. This cell featured a novel concept of a
porous electronically conductive faradaic membrane instead of the traditional
ion-selective ceramic membrane. LDBs are attractive for stationary storage
applications but need mitigation against self-discharge. In the instant battery
chemistry, Li|LiCl-PbCl$_2$|Pb, reducing the diffusion coefficient of lead ions
can be a way forward and a solution can be the addition of PbO to the
electrolyte. The latter acts as a supplementary barrier and complements the
function of the faradaic membrane. The remedial actions improved the cell's
coulombic efficiency from 92% to 97% without affecting the voltage efficiency.
In addition, the limiting current density of a 500 mAh cell increased from 575
to 831 mA cm$^{-2}$ and the limiting power from 2.53 to 3.66 W. Finally, the
effect of PbO on the impedance and polarization of the cell was also studied.
