A commentary on an anode-free cell design with electrochemically stable sodium borohydride solid electrolyte and pelletized aluminium current collector for sodium all-solid-state batteries is presented. First, the viable strategies for implementing anode-free configuration utilizing solid-state electrolytes are briefly reviewed. Then, the remarkable work of Meng et al. on designing an anode-free sodium all-solid-state battery is elucidated. Finally, the significance of Meng’s work is discussed.

As the persistent concerns regarding sluggish reaction kinetics and insufficient conductivities of sulfur cathodes in all-solid-state Li–S batteries (ASSLSBs), numerous carbon additives and solid-state electrolytes (SSEs) have been incorporated into the cathode to facilitate ion/electron pathways around sulfur. However, this has resulted in a reduced capacity and decomposition of SSEs. Therefore, it is worth exploring neotype sulfur hosts with electronic/ionic conductivity in the cathode. Herein, we present a hybrid cathode composed of few-layered S/MoS₂/C nanosheets (<5 layers) that exhibits high-loading and long-life performance without the need of additional carbon additives in advanced ASSLSBs. The multifunctional MoS₂/C host exposes the abundant surface for intimate contacting sites, in situ-formed Li_xMoS₂ during discharging as mixed ion/electron conductive network improves the S/Li₂S conversion, and contributes extra capacity for the part of active materials. With a high active material content (S + MoS₂/C) of 60 wt% in the S/MoS₂/C/Li₆PS₅Cl cathode composite (the carbon content is only ~3.97 wt%), the S/MoS₂/C electrode delivers excellent electrochemical performance, with a high reversible discharge capacity of 980.3 mAh g⁻¹ (588.2 mAh g⁻¹ based on the whole cathode weight) after 100 cycles at 100 mA g⁻¹. The stable cycling performance is observed over 3500 cycles with a Coulombic efficiency of 98.5% at 600 mA g⁻¹, while a high areal capacity of 10.4 mAh cm⁻² is achieved with active material loading of 12.8 mg cm⁻².

The point-to-point contact mechanism in all-solid-state Li-S batteries (ASSLSBs) is not as efficient as a liquid electrolyte which has superior mobility in the electrode, resulting in a slower reaction kinetics and inadequate ionic/electronic conduction network between the S (or Li₂S), conductive carbon, and solid-state electrolytes (SSEs) for achieving a swift (dis)charge reaction. Herein, a series of hybrid ionic/electronic conduction triple-phase interfaces with transition metal and nitrogen co-doping were designed. The graphitic ordered mesoporous carbon frameworks (TM-N-OMCs; TM = Fe, Co, Ni, and Cu) serve as hosts for Li₂S and Li₆PS₅Cl (LPSC) and provide abundant reaction sites on the triple interface. Results from both experimental and computational research display that the combination of Cu-N co-dopants can promote the Li-ion diffusion for rapid transformation of Li₂S with adequate ionic (6.73 × 10⁻⁴ S·cm⁻¹)/electronic conductivities (1.77 × 10⁻² S·cm⁻¹) at 25 °C. The as-acquired Li₂S/Cu-N-OMC/LPSC electrode exhibits a high reversible capacity (1147.7 mAh·g⁻¹) at 0.1 C, excellent capacity retention (99.5%) after 500 cycles at 0.5 C, and high areal capacity (7.08 mAh·cm⁻²).