The aqueous processing of LTO into electrodes suffers of lithium leaching upon contact with water, leading to a rapid rise in slurry pH and the final corrosion of the aluminum current collector. The addition of acids can suppress the corrosion issue. Herein, we demonstrate that the amount of phosphoric acid (PA) and the ball-milling speed are both affecting the pH value of the electrode slurry. At a ball-milling speed of 1100 rpm, a relatively higher amount of PA (4PA) is needed to prevent Al corrosion due to the generally greater increase of the slurry pH after ball milling for 2 h. Differently, at 800 rpm a relatively lower amount of PA (1PA) is sufficient to (largely) hinder the Al corrosion. Moreover, the ball-milling speed also influences the appearance of the eventual electrodes as well as the formation of rod-shaped lithium (titanium) phosphate particles. Besides, the addition of PA affects also the evolution of the LTO crystal structure. In fact, it reduces the μstrain upon de-/lithiation. In sum, the addition of PA leads to an enhanced cycling performance of LTO-based electrodes, which can be further improved by optimizing the electrode formulation and mixing parameters.