Lithium–metal electrodes are promising for developing next-generation lithium-based batteries with high energy densities. However, their implementation is severely limited by dendritic growth during battery cycling, which eventually short-circuits the battery. Replacing conventional liquid electrolytes with solid polymer electrolytes (SPEs) can suppress dendritic growth. Unfortunately, in SPEs the high stiffness required for suppressing dendrites comes at the expense of efficient lithium-ion transport. Some polymer-based composite electrolytes, however, enable the decoupling of stiffness and ionic conductivity. This study introduces a composite SPE comprised of a relatively soft poly(ethylene oxide-co-epichlorohydrin) (EO-co-EPI) statistical copolymer with high ionic conductivity and cellulose nanofibers (CNFs), a filler with extraordinary stiffness sourced from abundant cellulose. CNF-reinforcement of EO-co-EPI increases the storage modulus up to three orders of magnitude while essentially maintaining the SPE's high ionic conductivity. The composite SPE exhibits good cycling ability and electrochemical stability, demonstrating its utility in lithium metal batteries.

Lithium metal anodes have been pursued for decades as a way to significantly increase the energy density of lithium-ion batteries. However, safety risks caused by flammable liquid electrolytes and short circuits due to lithium dendrite formation during cell cycling have so far prevented the use of lithium metal in commercial batteries. Solid polymer electrolytes (SPEs) offer a potential solution if their mechanical properties and ionic conductivity can be simultaneously engineered. Here, we introduce a family of SPEs that are scalable and easy to prepare with a photopolymerization process, synthesized from amphiphilic acrylic polymer conetworks based on poly(ethylene glycol), 2-hydroxy-ethylacrylate, norbornyl acrylate, and either lithium bis (trifluoromethanesulfonyl) imide (LiTFSI) or a single-ion polymethacrylate as lithium-ion source. Several conetworks were synthesized and cycled, and their ionic conductivity, mechanical properties, and lithium transference number were characterized. A single-ion-conducting polymer electrolyte shows the best compromise between the different properties and extends the calendar life of the cell.

The combination of block copolymer self-assembly and polymer phase separation with sol–gel chemistry enables the optimisation of Li ₄ Ti ₅ O ₁₂ (LTO) microspheres with size-tuneable carbon-coated mesopores, resulting in excellent electrochemical performance.

Nanocomposites consisting of a polymer matrix and metallic nanoparticles can merge the functional, structural, and mechanical properties of the two components and are useful for applications that range from catalysis to soft electronics. Gaining spatial control over the nanoparticle incorporation is useful, for example to confine catalytic sites or create electrically conducting pathways. Here, we show that this is possible by the controlled disassembly of a metallosupramolecular polymer containing zerovalent platinum complexes to form nanoparticles in situ. To achieve this, a telechelic poly(ethylene-co-butylene) was end-functionalized with diphenylacetylene ligands and chain-extended through the formation of bis(2-alkyne)Pt0 complexes. These complexes are stable at ambient conditions, but they can be dissociated upon heating or exposure to ultraviolet light, which allows producing Pt nanoparticles when and where needed and without auxiliary reagents or formation of by-products. This approach was exploited to create objects with well-defined catalytically active areas.