To address the issue of temperature increase in battery modules using liquid cooling plates, a convex pack structure within the flow channel is proposed to enhance flow efficiency. High temperatures can lead to battery performance deterioration, increased safety risks, and reduced service life. The optimal parameters for the convex structure (radius, transverse spacing, and longitudinal spacing) were determined through simulation analysis and orthogonal experiments. The effects of discharge rate, ambient temperature, coolant inlet temperature, and inlet speed on the heat dissipation of the battery module were also studied. The results show that the convex pack structure enhances heat transfer by increasing the contact area and fluid velocity while inducing eddy currents to achieve lateral mixing. The optimal parameters were found to be: radius (r) = 0.75 mm, horizontal spacing (x) = 3.50 mm, and vertical spacing (y) = 4.50 mm. At low discharge rates, the battery performs well, but high discharge rates negatively affect temperature uniformity. An increase in ambient temperature raises the temperature difference and maximum battery temperature. Lower coolant inlet temperatures reduce the maximum temperature but may result in uneven temperature distribution. Achieving a balanced coolant flow rate is essential to minimize temperature variations and control pressure buildup. This research introduces an innovative heat transfer structure, the convex pack, which significantly improves cooling efficiency. Further research on enhanced heat transfer structures is necessary to continue advancing cooling technologies for battery modules.