<p>An ultrasound-assisted electrodeposition method was employed to fabricate cobalt-nickel layered double hydroxide thin films on a carbon cloth substrate. The research delved into the effects of ultrasound power and time on the electrode’s morphology, chemical structure, lattice structure, and electrochemical kinetics. Compared to conventional electrodeposition, using the ultrasound-assisted method reduced the pore size on cobalt-nickel layered double hydroxide and enlarged the electroactive surface area. This led to a significant reduction in the Warburg impedance of cobalt-nickel layered double hydroxide and an enhancement in its electrochemical kinetic properties, which enhanced its sodium ion adsorption capability. The ultrasound-assisted method regulated the chemical and lattice structures of the electro-deposited cobalt-nickel layered double hydroxide. It increased the proportion of crystalline regions and accelerated the intercalation and deintercalation of sodium ions, and improved the electrode’s reversibility. By selecting appropriate ultrasound power and time, the electrochemical performance of cobalt-nickel layered double hydroxide was effectively enhanced. The pseudocapacitor constructed with the cobalt-nickel layered double hydroxide achieved a maximum specific capacitance of 2446.9&#xa0;F g⁻¹ and an energy density of up to 148.6 Wh kg⁻¹ at a power density of 445.8&#xa0;W kg⁻¹. The ultrasound-assisted electrodeposition method presented great potential for the development of new high-performance electrochemical energy storage materials.</p> Graphical abstract <p></p>