Intermittent shading by trees and clouds can cause rapid changes in photovoltaic power generation which may introduce voltage variations in low-voltage distribution networks. Investigations into the impact of these rapid changes in generation on network voltage sag/swell show they may be mitigated using battery energy storage systems. A test system consisting of nine houses with real PV irradiance data, battery, and load were used in the modelling. From the simulation results it was found that battery storage can reduce the associated voltage variations, depending on its location. A charging-discharging algorithm for the battery was developed and it was found that if the battery is placed and controlled appropriately the voltage variations and peak load on the main grid may be reduced significantly.