Lithium-ion batteries have become the focus of research interest, thanks to their numerous benets for vehicle applications. One main limitation of these technologies resides in the battery ageing. The eects of battery ageing limit its performance and occur throughout its whole life, even if the battery is used or not, which is a major drawback on real usage. Furthermore, degradations take place in every condition, but in dierent proportions as usage and external conditions interact to provoke degradations. The ageing phenomena are highly complicated to characterize due to the factors cross-dependence. This paper reviews various aspects of recent research and developments, from dierent elds, on Lithium-ion battery ageing mechanisms and estimations. A summary of techniques, models and algorithms used for battery ageing estimation (SOH, RUL), going from a detailed electrochemical approach to statistical methods based on data, are presented.

In this paper we propose a mechanistic model describing the coupling between the polymer electrolyte fuel cell ͑PEFC͒ membrane electrodes assembly ͑MEA͒ electrocatalysis and the cathode carbon catalyst-support corrosion. The electrocatalysis description includes our previously introduced irreversible thermodynamics nanoscale models of the electrochemical reactions ͑hydrogen oxidation reaction/oxygen reduction reaction͒ coupled with the catalyst/ionomer interface double layer phenomena. Physically, the model describes the feedback between the instantaneous performance and the intrinsic cathode carbon oxidation process. It allows exploring the impact of the operating conditions ͑nominal current, reactant gas pressures, temperature, etc.͒ and the initial electrodes compositions ͑carbon and platinum loadings͒ on the PEFC MEA durability. Some numerical simulations show agreement with experimental knowledge already reported in literature, in particular, when the anode chamber is partially exposed to oxygen ͑induced by polymer electrolyte membrane crossover or fuel starvation͒, cathode thickness decrease and cell potential decay are predicted. Furthermore, we found that cathode damage increases as platinum loading increases and as platinum nanoparticles size decreases. Moreover, carbon corrosion favors the platinum coarsening; competition between carbon oxidation reaction and electrocatalytic mechanisms is investigated. Simulations also suggest that an "optimal" external load current inducing a "maximal" durability exists. The sensitivities of the electrochemical impedance spectra to the operating conditions and simulated operation time are also provided.

Proton Exchange Membrane Fuel Cells (PEMFC) are energy efficient and environmentally friendly alternatives to conventional energy conversion systems in many yet emerging applications. In order to enable prediction of their performance and durability, it is crucial to gain a deeper understanding of the relevant operation phenomena, e.g., electrochemistry, transport phenomena, thermodynamics as well as the mechanisms leading to the degradation of cell components. Achieving the goal of providing predictive tools to model PEMFC performance, durability and degradation is a challenging task requiring the development of detailed and realistic models reaching from the atomic/molecular scale over the meso scale of structures and materials up to components, stack and system level. In addition an appropriate way of coupling the different scales is required. This review provides a comprehensive overview of the state of the art in modeling of PEMFC, covering all relevant scales from atomistic up to system level as well as the coupling between these scales. Furthermore, it focuses on the modeling of PEMFC degradation mechanisms and on the coupling between performance and degradation models.