Rapid growth in the market for electric vehicles is imperative, to meet global targets for reducing greenhouse gas emissions, to improve air quality in urban centres and to meet the needs of consumers, with whom electric vehicles are increasingly popular. However, growing numbers of electric vehicles present a serious waste-management challenge for recyclers at end-of-life. Nevertheless, spent batteries may also present an opportunity as manufacturers require access to strategic elements and critical materials for key components in electric-vehicle manufacture: recycled lithium-ion batteries from electric vehicles could provide a valuable secondary source of materials. Here we outline and evaluate the current range of approaches to electric-vehicle lithium-ion battery recycling and re-use, and highlight areas for future progress.

This article describes a variable temperature solid-state NMR and single crystal X-ray/neutron diffraction study of the hybrid perovskites (CH ₃ NH ₃ )PbX ₃ (X = I, Br and Cl).

O3-type layered oxide materials are considered to be a highly suitable cathode for sodium-ion batteries (NIBs) due to their appreciable specific capacity and energy density. However, rapid capacity fading caused by serious structural changes and interfacial degradation hampers their use. A novel Sn-modified O3-type layered NaNi_1/3Fe_1/3Mn_1/3O₂ cathode is presented, with improved high-voltage stability through simultaneous bulk Sn doping and surface coating in a scalable one-step process. The bulk substitution of Sn⁴⁺ stabilizes the crystal structure by alleviating the irreversible phase transition and lattice structure degradation and increases the observed average voltage. In the meantime, the nanolayer Sn/Na/O composite on the surface effectively inhibits surface parasitic reactions and improves the interfacial stability during cycling. A series of Sn-modified materials are reported. An 8%-Sn-modified NaNi_1/3Fe_1/3Mn_1/3O₂ cathode exhibits a doubling in capacity retention increase after 150 cycles in the wide voltage range of 2.0-4.1 V vs Na/Na⁺ compared to none, and 81% capacity retention is observed after 200 cycles in a full cell vs hard carbon. This work offers a facile process to simultaneously stabilize the bulk structure and interface for the O3-type layered cathodes for sodium-ion batteries and raises the possibility of similar effective strategies to be employed for other energy storage materials.

Materials displaying high oxide-ion conductivity have attracted considerable interest due to technological applications in solid oxide fuel cells (SOFCs), oxygen sensors and separation membranes. This has driven research into the identification of new classes of oxide-ion conductors, and in this review, work on the recently discovered apatite-type silicate/germanate oxide-ion conductors is presented. In contrast to the traditional perovskite- and fluorite-based oxide-ion conductors, in which conduction proceeds via oxygen vacancies, the research on these apatite systems suggests that the conductivity involves interstitial oxide-ions. In addition, the flexibility of the tetrahedral (Si/GeO₄) framework also plays a crucial role in facilitating oxide-ion migration. Detailed doping studies have shown that the apatite structure is able to accommodate a large range of dopants (in terms of both size and charge state), and the influence of these dopants on the conductivity is discussed.