Lower rates employed during the writing step of the cycle induce a mosaic lithiation scheme. In this scenario, the reaction primarily occurs for smaller particles, characterized by faster kinetics and a lower energy barrier. Greater overpotentials are instead imposed at higher rates, activating more particles by overcoming size-dependent energy barriers. This results in a larger population of phase-separated particles, delaying their relaxation towards a mosaic scheme due to the coexistence of two phases with the same chemical potential. When the reading current is applied, the former case requires a greater overpotential to activate the single-phase particles and sustain the current with a limited number of available particles. In contrast, the latter case does not require overcoming the nucleation barrier and can evenly distribute the reaction among the majority of particles. This nuanced interplay between current rates and phase-separation dynamics sheds light on the crucial role of activation barriers and population dynamics in governing the electrochemical behavior of these systems. Multiple studies, primarily focusing on LFP, assessed the non-trivial multi-particle and single-particle reaction path that phase-separating materials follow during (de)intercalation . Early descriptions relied on a domino-cascade model, suggesting a mosaic particle-by-particle (de)lithiation process . However, subsequent experimental 9,10 and computational studies have provided compelling evidence that the active particle population is intricately linked to the applied rate, challenging the initial univocal interpretation. Building on these findings, other works focused on the investigation of the metastable solid solution (characteristic of LFP but not universal to all phase-separating materials) and the relaxation behavior , providing a foundation for the understanding of currentinduced phenomena. Specifically, Deng and coworkers 7 characterized the unexpected change in overpotential during quasi-equilibrium discharge of LFP following a high-rate current pulse, revealed by the study of Katrašnik et al. , through X-ray microscopy and phase-field modeling on reactionlimited micro-platelet particles. Notably, offering valuable insights, they did not quantitatively assess the strong consequences of these pulses on the subsequent high-rate operating conditions. Our protocol, closer to commercially relevant rates, reveals the impact of these non-equilibrium phenomena on typical battery operations. The thermodynamic interpretation of it (Fig. ), obtained by combining modeling and operando monitoring of individual particles, opens the doors to improved protocol design for both deeper fundamental understating and battery management strategies.