The authors present a method to prepare high-concentration graphene dispersions (up to 1.2 mg/ml) using low-power sonication for extended periods (up to 460 hours). This process reduces flake size, with dimensions scaling as \( t^{1/2} \), while maintaining a mean flake length above 1 μm. Raman spectroscopy indicates the introduction of defects, primarily edge defects rather than basal-plane defects. The dispersions are used to prepare high-quality free-standing graphene films with reasonable electrical and mechanical properties. The dispersions remain stable when heavily diluted with water, making them suitable for various applications. The study highlights the potential of this method for large-scale, high-throughput processing of graphene.The authors present a method to prepare high-concentration graphene dispersions (up to 1.2 mg/ml) using low-power sonication for extended periods (up to 460 hours). This process reduces flake size, with dimensions scaling as \( t^{1/2} \), while maintaining a mean flake length above 1 μm. Raman spectroscopy indicates the introduction of defects, primarily edge defects rather than basal-plane defects. The dispersions are used to prepare high-quality free-standing graphene films with reasonable electrical and mechanical properties. The dispersions remain stable when heavily diluted with water, making them suitable for various applications. The study highlights the potential of this method for large-scale, high-throughput processing of graphene.