P2-type layered oxides with the general Na-deficient composition Na _x TMO₂ (x < 1, TM: transition metal) are a promising class of cathode materials for sodium-ion batteries. The open Na⁺ transport pathways present in the structure lead to low diffusion barriers and enable high charge/discharge rates. However, a phase transition from P2 to O2 structure occurring above 4.2 V and metal dissolution at low potentials upon discharge results in rapid capacity degradation. In this work, we demonstrate the positive effect of configurational entropy on the stability of the crystal structure during battery operation. Three different compositions of layered P2-type oxides were synthesized by solid-state chemistry, Na_0.67(Mn_0.55Ni_0.21Co_0.24)O₂, Na_0.67(Mn_0.45Ni_0.18Co_0.24Ti_0.1Mg_0.03)O₂ and Na_0.67(Mn_0.45Ni_0.18Co_0.18Ti_0.1Mg_0.03Al_0.04Fe_0.02)O₂ with low, medium and high configurational entropy, respectively. The high-entropy cathode material shows lower structural transformation and Mn dissolution upon cycling in a wide voltage range from 1.5 to 4.6 V. Advanced operando techniques and post-mortem analysis were used to probe the underlying reaction mechanism thoroughly. Overall, the high-entropy strategy is a promising route for improving the electrochemical performance of P2 layered oxide cathodes for advanced sodium-ion battery applications.

Rechargeable aqueous Zn-ion batteries (ZIBs) have gained great attention due to their high safety and the natural abundance of Zn. Unfortunately, the Zn metal anode suffers from dendrite growth due to nonuniform deposition during the plating/stripping process, leading to a sudden failure of the batteries. Herein, Cu coated Zn (Cu–Zn) was prepared by a facile pretreatment method using CuSO₄ aqueous solution. The Cu coating transformed into an alloy interfacial layer with a high affinity for Zn, which acted as a nucleation site to guide the uniform Zn nucleation and plating. As a result, Cu–Zn demonstrated a cycling life of up to 1600 h in the symmetric cells and endowed a stable cycling performance with a capacity of 207 mAh g⁻¹ even after 1000 cycles in the full cells coupled with a V₂O₅-based cathode. This work provides a simple and effective strategy to enable uniform Zn deposition for improved ZIBs.

The promise of silicon anodes for lithium‐ion batteries (LIBs), owing to the high theoretical capacity, is significantly affected by the huge volume changes (over 300%) during the lithiation/delithiation process. This leads to particle cracking during cycling impacting the electrode at multiple levels, from continued solid‐electrolyte interphase formation, particle contact losses, to delamination of the coating from the current collector. As a results, there is increased electrolyte consumption, and significantly shortened cycle life, hindering its commercial application. The problem is severe for commercially viable larger silicon microparticles (SiMPs > 1 µm). Herein, the cycling of 325 mesh (≤45 µm) SiMPs is successfully demonstrated using a composite binder consisting of inner graphene oxide coating and outside DNA polymer. The resultant hierarchical structure, with cycling‐induced 3D interconnection, maintains the electrodes integrity, as well as helps to stabilize the SEI. Thus, an excellent cycle life is observed, retaining a capacity of 808 mAh·g⁻¹ after 450 cycles at a current density of 840 mA·g⁻¹. This double protection strategy with a robust particle coating and a chemically bonded soft polymer offers an effective strategy for cyclability of SiMPs in practical LIBs.

Lithium‐ion capacitors (LICs), potentially bring together the advantages of batteries and supercapacitors. For the faradaic anodes, nanostructured carbonaceous materials hold immense potential, in contrast to graphite where limitations in Li‐ion diffusivity exist. Herein, onion‐like carbons (OLCs), synthesized from Fe‐BTC metal‐organic framework (MOF), is implemented as the LIC anode, owing to its high charge storage capacity and rate capability as compared to graphite. The enhanced charge storage and Li‐ion transference in OLCs was understood to be due to hierarchical porosity with accessible inner voids along with high defect concentration. Therefore, full‐LIC cells with OLC anodes exhibited a markedly higher specific capacitance and an enhanced rate capability than graphite‐LIC. The OLC‐LIC achieved an outstanding maximum energy density of 224 Wh kg⁻¹ at 122 W kg⁻¹ and maximum power density of 14436 W kg⁻¹ at 80 Wh kg⁻¹. Thus, MOF‐derived OLC with distinctive morphology is presented as a highly attractive anode for practical LIC systems.

Electrochemical cation intercalation into 2D NiPS₃ leads either to reduction of the (P₂S₆)⁴⁻ units (Li example) or Ni cations (Na example), or causes electrochemical reduction and decomposition of EMIM cations within the van der Waals interlayers.