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The lithium metal anode is regarded as ideal for high-energy rechargeable batteries. Unfortunately, the uncontrolled lithium dendritic growth and the infinite volume expansion upon cycling result in low Coulombic efficiency, fast capacity decay and safety issues. Herein, a mismatch electrical-conductivity framework has been designed as a stable host to regulate lithium deposition behaviour. Due to the ionic conductivity of the lithiophilic layer and the electron conductivity of hollow carbon nanofibres (HCF), lithium metal is preferentially deposited into and encapsulated by the HCF, resulting in greatly improved electrochemical performance. The heat generation upon lithium storage and release in the Al 2 O 3 coated HCF (A–HCF) during cycling is lower compared to the plating/stripping on copper foil. The A-HCF electrodes show high Coulombic efficiency (97%) upon 500 cycles employing a conventional, alkyl carbonate-based electrolyte, demonstrating improved reversibility of Li plating/stripping. Complete cells assembled employing LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NMC811)-based positive electrodes exhibit high capacity retention (94%) after 120 cycles at 1 C, delivering a high energy density (363 Wh per kg of NMC811). Even upon cycling at 5 C rate, the cells, employing less than three times excess lithium, deliver a very high capacity (133 mAh per g of NMC811) for 50 cycles. The mismatch electrical conductivity skeleton effectively regulates the lithium deposition behavior, guiding the Li metal uniform plating on the inside and along the surface of the hollow nanofibers and by this restraining dendritic Li formation as well as decreasing heat generation during cycling. [Display omitted] • Effect of a mismatch electrical conductivity framework host (A-HCF) with plentiful cavities to regulate Li deposition behavior. • Li storage mechanism and deposition morphology. • Li storage upon long-term cycling. • Heat generation upon Li storage and release by microcalorimetry. • Electrochemical performance of Li metal cells. [ABSTRACT FROM AUTHOR]

Lithium metal is regarded as a great promising anode for high energy density lithium-based batteries. Yet its practical application is severely restricted by uncontrollable growth of lithium dendrites and resultant potential safety hazard. Herein, an integrated architecture with 3D micro-nano structured Cu skeleton and crosslinked fluorine (F)-doped carbon nanofiber network (MNCu/FC) is constructed as host for lithium metal anode via a facile and scalable slurry-coating method. The conductive 3D architecture built by Cu skeleton and carbon network effectively promotes charge transfer and inhibits Li dendrites growth. Besides, the crosslinked F-doped carbon nanofibers act as lithiophilic seeds to regulate uniform Li nucleation and deposition, and superior lithiophilicity of F-doped carbon nanofiber is demonstrated via density functional theory calculation. As a result, the 3D MNCu/FC facilitates a dendrite-free lithium metal anode with lower lithium nucleation overpotential and enhanced electrochemical performance in half and full cells compared with bare Cu. Image 1 • Scalable slurry-coating is introduced to construct 3D lithiophilic Li metal host. • F-doped carbon facilitate low nucleation overpotential and uniform Li deposition. • Integrated 3D host offers abundant accommodation sites for Li volume dilatation. • MNCu/FC host displays superior cycling stability and high CEs. [ABSTRACT FROM AUTHOR]