We present gas-permeable, ultrathin, and stretchable electrodes enabled by self-assembled porous substrates and conductive nanostructures. An efficient and scalable breath figure method is employed to introduce the porous skeleton, and then silver nanowires (AgNWs) are dip-coated and heat-pressed to offer electric conductivity. The resulting film has a transmittance of 61%, sheet resistance of 7.3 Ω/sq, and water vapor permeability of 23 mg cm–2 h–1. With AgNWs embedded below the surface of the polymer, the electrode exhibits excellent stability in the presence of sweat and after long-term wear. We demonstrate the promising potential of the electrode for wearable electronics in two representative applications: skin-mountable biopotential sensing for healthcare and textile-integrated touch sensing for human–machine interfaces. The electrode can form conformal contact with human skin, leading to low skin–electrode impedance and high-quality biopotential signals. In addition, the textile electrode can be used in a self-capacitance wireless touch sensing system.

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In dual-ion batteries, the electrolyte solutions of LiPF6 dissolved into ethylmethyl carbonate (EMC) have demonstrated excellent compatibility with a graphite positive electrode. To further optimize the solutions, typical concentrations of LiPF6 are applied in Li/graphite cells. Traditional electrochemical tests, including galvanostatic charge–discharge and cyclic voltammetry, preliminarily verify that 2 M LiPF6-EMC is an appropriate choice for electrolyte solution. Furthermore, in situ XRD combined with EQCM clarified the crystal structural evolutions of the graphite electrode and the mass change during the PF6 – anion storage in the graphite electrode. EMC transport is discovered in the opposite direction of the anion transport between the graphite electrode and the electrolyte solutions. NMR and IR analyses were explored to characterize the solvation states of anions in the solutions. In addition, the long-term cycling and rate capability of the graphite electrode are tested to address EMC’s role. A suitable concentration of EMC is vital for the satisfactory performance of the graphite positive electrode.