A silicon (Si) anode with a high theoretical specific capacity (3579 mA h g⁻¹) offers great promise for realizing high-energy solid-state batteries (SSBs). However, given Si's huge volume variations during cycling, sluggish kinetics and unfavorable interface stability with a solid-state electrolyte (SSE), its practical potential in SSBs has not been fully exploited. Herein, we propose a design of highly dense Ag nanoparticles decorated with porous microsized Si, which is coated by thin-layer carbon (PS–Ag–C) working as a high-performance anode for boosting SSB performance. Specifically, the mechanical stress at the interface, originating from a large volume change of Si, can be alleviated by the highly porous architecture. Meanwhile, continuous charge transfer within Si can be achieved by the introduction of Ag nanoparticles, a thin carbon layer and the as-formed Ag–Li alloys, which contribute to high-rate capability and stable cycling performance. Furthermore, coupled with a poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP)/Li_1.3Al_0.3Ti_1.7(PO₄)₃ (LATP) SSE with low mobility, a flow-domain LiF-rich solid–electrolyte-interphase (SEI) is formed, ensuring desirable interfacial and mechanical stability. Accordingly, the as-fabricated PS–Ag–C anode achieves high reversible capacities of 3030.3 mA h g⁻¹ at 0.2 A g⁻¹ with an initial Coulombic efficiency of 90% and 1600 mA h g⁻¹ over 500 cycles at 1 A g⁻¹, respectively. In particular, we observed that the highest areal capacity reaches 4.0 mA h cm⁻² over 100 cycles at 0.5 A g⁻¹ in Si-based SSBs with organic–inorganic composite SSEs. Moreover, a solid-state full cell assembled with the as-obtained PS–Ag–C anode and LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) cathode demonstrates high capacity and desirable cycling stability. This work provides new insights into developing a high-capacity and durable Si anode for high-performance SSBs.

The advancement of aqueous zinc-based batteries is greatly restricted by zinc dendrites. One potential solution to this challenge lies in the employment of high-modulus separators. However, achieving both high modulus and large ionic conductivity in a single separator remains a formidable task. Inspired by the wood architecture, this study breaks this trade-off by designing an anisotropic and biodegradable separator. This design significantly improves the modulus along the oriented direction while simultaneously facilitating fast Zn²⁺ ion transport through aligned vertical channels. Additionally, this configuration resolves the contradiction between low separator thickness and good dendrite-inhibition capability. These benefits are supported by finite element simulations and comprehensive experimental validation, which also underscore the critical role of modulus enhancement for separators. By employing the anisotropic separator, a prolonged life span is realized for Zn||Zn cells, along with improved cyclability in full batteries. This work presents a strategy for separator modification towards dendrite-free metal batteries.

An all-electrochem-active Si/Li ₂₁ Si ₅ anode was designed, in which the Li ₂₁ Si ₅ served as efficient ionic/electronic channel and expansion buffer. It achieved an ultra-high ICE of 97.8% and a low expansion rate of 18.8% at a capacity of 17.9 mA h cm ⁻² .

Silicon-based all-solid-state batteries offer high energy density and safety but face significant application challenges due to the requirement of high external pressure. In this study, a Li₂₁Si₅/Si–Li₂₁Si₅ double-layered anode is developed for all-solid-state batteries operating free from external pressure. Under the cold-pressed sintering of Li₂₁Si₅ alloys, the anode forms a top layer (Li₂₁Si₅ layer) with mixed ionic/electronic conduction and a bottom layer (Si–Li₂₁Si₅ layer) containing a three-dimensional continuous conductive network. The resultant uniform electric field at the anode|SSE interface eliminates the need for high external pressure and simultaneously enables a twofold enhancement of the lithium-ion flux at the anode interface. Such an efficient ionic/electronic transport system also facilitates the uniform release of cycling expansion stresses from the Si particles and stabilizes bulk-phase and interfacial structure of anode. Consequently, the Li₂₁Si₅/Si–Li₂₁Si₅ anode exhibited a critical current density of 10 mA cm⁻² at 45 °C with a capacity of 10 mAh cm⁻². And the Li₂₁Si₅/Si–Li₂₁Si₅|Li₆PS₅Cl|Li₃InCl₆|LCO cell achieve an high initial Coulombic efficiency of (97 ± 0.7)% with areal capacity of 2.8 mAh cm⁻² at 0.25 mA cm⁻², as well as a low expansion rate of 14.5% after 1000 cycles at 2.5 mA cm⁻².

While aqueous zinc-ion batteries exhibit great potential, their performance is impeded by zinc dendrites. Existing literature has proposed the use of hydrogel electrolytes to ameliorate this issue. Nevertheless, the mechanical attributes of hydrogel electrolytes, particularly their modulus, are suboptimal, primarily ascribed to the substantial water content. This drawback would severely restrict the dendrite-inhibiting efficacy, especially under large mass loadings of active materials. Inspired by the structural characteristics of wood, this study endeavors to fabricate the anisotropic carboxymethyl cellulose hydrogel electrolyte through directional freezing, salting-out effect, and compression reinforcement, aiming to maximize the modulus along the direction perpendicular to the electrode surface. The heightened modulus concurrently serves to suppress the vertical deposition of the intermediate product at the cathode. Meanwhile, the oriented channels with low tortuosity enabled by the anisotropic structure are beneficial to the ionic transport between the anode and cathode. Comparative analysis with an isotropic hydrogel sample reveals a marked enhancement in both modulus and ionic conductivity in the anisotropic hydrogel. This enhancement contributes to significantly improved zinc stripping/plating reversibility and mitigated electrochemical polarization. Additionally, a durable quasi-solid-state Zn//MnO ₂ battery with noteworthy volumetric energy density is realized. This study offers unique perspectives for designing hydrogel electrolytes and augmenting battery performance.