Establishing energy storage systems beyond conventional lithium ion batteries requires the development of novel types of electrode materials. Such materials should be capable of accommodating ion species other than Li+, and ideally, these ion species should be of multivalent nature, such as Al3+. Along this line, we introduce a highly porous aerogel cathode composed of reduced graphene oxide, which is loaded with nanostructured SnO2. This binder-free hybrid not only exhibits an outstanding mechanical performance, but also unites the pseudocapacity of the reduced graphene oxide and the electrochemical storage capacity of the SnO2 nanoplatelets. Moreover, the combination of both materials gives rise to additional intercalation sites at their interface, further contributing to the total capacity of up to 16 mAh cm−3 at a charging rate of 2 C. The high porosity (99.9%) of the hybrid and the synergy of its components yield a cathode material for high-rate (up to 20 C) aluminum ion batteries, which exhibit an excellent cycling stability over 10,000 tested cycles. The electrode design proposed here has a great potential to meet future energy and power density demands for advanced energy storage devices.

The ubiquity of portable electronics underlines the importance of high-performance flexible metal-ion batteries and the necessity of their development. Considering their ecological footprint, the application of eco-friendly recyclable battery components has become the greatest challenge and the focal point of research. However, less attention has been devoted to the development of shapeconformable separators with minimal impact on the battery performance and the environment. It is therefore imperative to develop a rational design of next-generation eco-friendly separators with an optimized structure−performance relationship. In this work, a highly flexible and eco-friendly cellulose-nanofiber aerogel (CNF-AG) separator is developed and its dynamic behavior in battery cells is assessed. The tailored channel-like structure with a meso-and macroporosity of 99.5% and good mechanical stability results in superior performance to the commercial glass fiber (GF) membranes and other cellulose-based separators. Its structure with a well-connected pore network and affinity to carbonate-based and ionic liquid electrolytes realize an electrolyte uptake of 12 000%. Furthermore, an effective diffusion coefficient of 1.70 × 10 −10 m 2 s −1 , only 16% lower than that of the bulk electrolyte, yielded an ionic conductivity of 2.64 mS cm −1 . Assessing the CNF-AG in lithium-ion batteries (LIBs) revealed a stable interfacial resistance over time, reaching 380 Ω, one-third of that obtained for GF. Accordingly, superior electrochemical performance is observed, achieving good cycling stability up to 200 cycles. Moreover, its applicability in aluminum-ion batteries is demonstrated. The outstanding structure−performance relationships of the developed CNF-AG indicate its superiority as a shape-conformable biodegradable separator suitable for metal-ion batteries.

The emerging market of high voltage electronics signified the importance of the development of novel cathodes with high operating potentials. Lithium nickel phosphate (LNP), a suitable candidate with an operating...

This work shows the feasibility of a self-supporting V2O5 nanofiber-based cathode for magnesium–lithium-ion batteries reaching an energy density of 280 W h kg−1.

Nickel phosphate octahydrate (Ni 3 (PO 4 ) 2 •8H 2 O) is a promising electrode material for next-generation energy storage devices. However, owing to the large initial irreversible capacity, its practical application is hindered. Prelithiation is a viable solution, nonetheless, usually associated with additional challenges in terms of safety, cost, and homogenous distribution of Li + . Herein, we report on a facile, cost-effective prelithiation method based on nanoarchitectonics for the synthesis of mesocrystalline Ni 3 (PO 4 ) 2 • 8H 2 O platelets. During their oriented self-assembly, the lithium phosphates present in the precursor act as the Li + source. A detailed, systematic investigation of the morphological evolution, from activation over nucleation to growth, revealed that the addition of a secondary phase with oxygen-containing functional groups accelerates the fabrication of complex multiscale hybrid materials. Accordingly, hybridization with graphene oxide (GO), cellulose nanofibers (CNF), and V 2 O 5 nanofibers (VNF) was demonstrated. The electrochemical assessment of the prelithiated multiscale material in the form of a free-standing aerogel revealed the benefits of the synergy of nanoarchitecture and prelithiation. Specifically, it decreases the effect of the initial capacity loss, facilitates ion intercalation, and introduces additional intercalation sites. Notably, dehydrated aerogels of the prelithiated nickel phosphate embedded in partially reduced GO deliver a significantly high capacity of 400 mAh g −1 when tested as the anode. The developed prelithiation strategy provides enlightenment for novel environmentally conscious synthesis routes for the commercial application of high-specific-capacity electrodes.