Ionogels are considered promising electrolytes for safe lithium‐ion batteries (LIBs) because of their low flammability, good thermal stability, and wide electrochemical stability window. Conventional ionic liquid‐based ionogels, however, face two main challenges; poor mechanical property and low Li‐ion transfer number. In this work, a novel solvate ionogel electrolyte (SIGE) based on an organic–inorganic double network (DN) is designed and fabricated through nonhydrolytic sol–gel reaction and in situ polymerization processes. The unprecedented SIGE possesses high toughness (bearing the deformation under the pressure of 80 MPa without damage), high Li‐ion transfer number of 0.43, and excellent Li‐metal compatibility. As expected, the LiFePO4/Li cell using the newly developed SIGE delivers a high capacity retention of 95.2% over 500 cycles, and the average Coulombic efficiency is as high as 99.8%. Moreover, the Ni‐rich LiNi0.8Co0.1Mn0.1O2 (NCM811)/Li cell based on the modified SIGE achieves a high Coulombic efficiency of 99.4%, which outperforms previous solid/quasi‐solid‐state NCM811‐based LIBs. Interestingly, the SIGE‐based pouch cells are workable under extreme conditions (e.g., severely deforming or clipping into segments). In terms of those unusual features, the as‐obtained SIGE holds great promise for next‐generation flexible and safe energy‐storage devices.

Lignin‐carbohydrate complexes (LCC) underpin the comprehensive properties of natural wood. Facile restoration of LCC analogues in paper is challenging because of the charge repulsion between negatively charged lignin and pulp fibrils. A camouflage strategy is discovered to prepare positively charged lignosulfonate–polyamide‐epichlorohydrin complex (LPC) nanoparticles, which are effectively incorporated in pulp through the “LPC–pulp” attraction instead of “lignosulfonate–pulp” repulsion. Water‐resistant LPC paper sheets are prepared in ≈20 min without pressurization. They exhibit high tensile strength (41 MPa), surviving boiling water treatment for 14 days, on par with the strength of pristine paper and certain plastics in a dry state. The camouflage strategy applies to various pulps and processing technologies, as exemplified by a paper separator showing exceptional electrolyte wettability and rate capability in lithium‐ion batteries. This work establishes advanced cellulose valorization with combined strength, water stability, and tailored microstructures replacing petroleum polymers in engineering and energy implications.

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The demand for fast-charging of lithium-ion batteries (LIBs) in modern electric transportation and wearable electronics is rapidly growing. However, commercially available graphite anodes still suffer from slow kinetics of lithium-ion diffusion and severe safety concerns of lithium plating when achieving the fast-charging goal. Here, it is demonstrated that the Li-ion diffusion kinetics of orthorhombic Nb2O5 nanotubes (T-Nb2O5 NTs) is enhanced by atomically precise manufacturing of nanoarchitectures. The controlled fabrication of T-Nb2O5 NTs with wall thicknesses from 24 to 43 nm is realized via atomic layer deposition (ALD) using electrospun polyacrylonitrile nanofibers as a sacrificing template. The wall thickness of T-Nb2O5 NTs can be precisely tuned by adjusting the number of ALD cycles. The relationship between the wall thicknesses and electrochemical performances is investigated in detail. The electrochemical kinetic analysis suggests that the lithium storage in T-Nb2O5 NTs is dominated by surface and intercalation pseudocapacitance. The morphology of T-Nb2O5 crystallites is found to have significant effects on the Li-ion insertion/extraction kinetics and the performance of the electrodes in LIBs. The resulting T-Nb2O5 NTs exhibit fast charge-storage kinetics and enable highly reversible insertion/extraction of Li ions without a phase change. This work may open up a new avenue for further development of intercalation-pseudocapacitive nanostructured materials for high-rate and ultrastable energy-storage devices.

and electronic transfer kinetics inside LIBs decline sharply at low temperatures (LT), including the sluggish Li-ion diffusion in the bulk electrolyte and active material, and inferior transportation ability across the electrode/electrolyte interface. [4] On the other hand, side reactions are prone to occur at high temperatures (HT), especially the cases of electrolyte decomposition and interfacial reactions between the electrode and electrolyte. [5] When LIBs are operated in a wide-temperature (WT) range, the issues at LT and HT need to be addressed simultaneously. [6] Notably, the interface stability inside LIBs plays a decisive role. [7] It is widely recognized that the interfacial properties dominate the Li-ion transportation kinetics significantly and trigger thermal runaway of LIBs. [8] Therefore, it is crucial to design and construct a desirable electrode/electrolyte interface with high Li + conductivity and thermal stability to achieve credible LIBs under harsh conditions. [9] Tremendous efforts have been devoted to modifying the electrode surface to improve interfacial kinetics and stability. [10] For instance, surface coating is an effective strategy to build an extra layer on the active material surface; and thus, the interfaces on the cathode and anode surface contribute to the enhanced interfacial properties simultaneously. [11] Nevertheless, constructing coating layers on the cathode and anode is usually complicated and energy-consuming. As the electrolytes in LIBs contact both the cathode and anode, task-specific electrolytes would be in favor of wanted interfaces on the electrode surface. [12] It is widely recognized that an inorganic-rich interface benefits Li-ion transportation and interfacial stability. [13] A thin and uniform LiF-abundant interface can be generated by using fluorine-containing additives and/or all fluorinated electrolytes, facilitating the interfacial Li + kinetic and boosting mechanical strength. [14] These behaviors have also been proved via the construction of Li 3 N-rich, LiS species-rich interfaces if N-and S-containing additives such as LiNO 3 or lithium bistrifluoromethanesulfonimide (LiTFSI) are introduced. [15] Despite these advances, it is challenging to attain a favorable cathode electrolyte interface (CEI) on the cathode and a task-specific solid electrolyte interface (SEI) on the anode simultaneously. [16] Besides,