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Rechargeable batteries are essential elements for many applications, ranging from portable use up to electric vehicles. Among them, lithium-ion batteries have taken an increasing importance in the day life. However, they suffer of several limitations: safety concerns and risks of thermal runaway, cost, and high carbon footprint, starting with the extraction of the transition metals in ores with low metal content. These limitations were the motivation for an intensive research to replace the inorganic electrodes by organic electrodes. Subsequently, the disadvantages that are mentioned above are overcome, but are replaced by new ones, including the solubility of the organic molecules in the electrolytes and lower operational voltage. However, recent progress has been made. The lower voltage, even though it is partly compensated by a larger capacity density, may preclude the use of organic electrodes for electric vehicles, but the very long cycling lives and the fast kinetics reached recently suggest their use in grid storage and regulation, and possibly in hybrid electric vehicles (HEVs). The purpose of this work is to review the different results and strategies that are currently being used to obtain organic electrodes that make them competitive with lithium-ion batteries for such applications.

The development and deployment of cost-effective and energy-efficient solutions for recycling end-of-life electric vehicle batteries is becoming increasingly urgent. Based on the existing literature, as well as original data from research and ongoing pilot projects in Canada, this paper discusses the following: (i) key economic and environmental drivers for recycling electric vehicle (EV) batteries; (ii) technical and financial challenges to large-scale deployment of recycling initiatives; and (iii) the main recycling process options currently under consideration. A number of policies and strategies are suggested to overcome these challenges, such as increasing the funding for both incremental innovation and breakthroughs on recycling technology, funding for pilot projects (particularly those contributing to fostering collaboration along the entire recycling value chain), and market-pull measures to support the creation of a favorable economic and regulatory environment for large-scale EV battery recycling.

This work encompasses modeling and experimental work to improve understanding of transport and other resistances for LiFePO 4 composite cathodes used in Li-ion batteries. Modeling LiFePO 4 active material requires consideration of the carbon coating around the particle, phase-change behavior, and diffusion in only one of the lattice dimensions of the crystal. Physically realistic parameters for the full-cell sandwich model were measured directly in separate experiments where possible. Despite the complexity of solid-state diffusion in this system, we found that a constant diffusion coefficient was generally adequate. The full model was compared to experiments of LiFePO 4 cathodes vs. lithium and good agreement was obtained for a range of electrode thicknesses and discharge rates. We found that a distribution of inter-particle contact resistances is needed to obtain this level of agreement if one wishes to keep all model parameters at physically realistic values. The model shows that resistances corresponding to bulk electronic conductivity and even more so, to local inter-particle contact are significant and in need of further optimization for the cells tested.

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