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As the "holy grail" of lithium battery anode materials, the lithium metal anode suffers from several fatal defects, such as infinite volume expansion and uncontrolled dendrite formation. Herein, a three-dimensional (3D) lithiophilic host that comprises MnO 2 nanoflowers in situ grown on Ni foam (MnO 2 @NF) is developed into a stable lithium metal anode. The 3D porous structure of Ni foam (NF) can greatly reduce the average current density of the electrode and relieve volume changes during the repeated plating/stripping process, in which the MnO 2 nanoflower arrays endow the 3D framework with high lithiophilicity, leading to a reduced lithium nucleation barrier and uniform lithium nucleation. It is found that the MnO 2 nanoarrays could transform into Ni/Li 2 O, which offers abundant lithium deposition sites, homogenizes Li + flux distribution, and ensures fast Li + transfer kinetics. These advantages of MnO 2 @NF enable dendrite-free lithium deposition behavior and excellent electrochemical performance. As a consequence, the asdesigned MnO 2 @NF host delivers a high Coulombic efficiency (CE) of 98.7% for 400 cycles in a half cell under 0.5 mA cm −2 , and an ultralong cycling lifespan of 2000 h with a low-voltage hysteresis of 18 mV is achieved in a symmetrical cell at 1 mA cm −2 . Furthermore, the Li-MnO 2 @NF//LiFePO 4 full cell also exhibits enhanced cyclic stability and rate performance, indicating the application prospects of Li-MnO 2 @NF as a stable lithium metal anode.

A silicon suboxide−carbon (SiO x /C, 1 ≤ x ≤ 2) composite anode of lithium-ion batteries (LIBs) with enhanced performance is prepared using an aqueous multicomponent binder technology. Considering the adhesive force, electrolyte absorption, and stability, different binders including sodium alginate (SA), polyacrylamide gel (PAM), polytetrafluoroethylene (PTFE), and their composites are evaluated. It is indicated that compared to other anodes with single-or multicomponent binders, the SiO x /C composite anode with PAM/SA/PTFE663 (PSAP663) binders exhibits strong adhesion, moderate electrolyte absorption ability, and a specific capacity of 427 mA h g −1 charge−discharged at 0.5 A g −1 after 300 cycles. The improvement of electrochemical performance is attributed to the comprehensive effects of composite binders, including the adhesion of active substances, surface protection, solution adsorption, conductive path, and so on. These results show that the PSAP663 binder has promising potential for application, which not only gives alternative practical schemes of the green binders for the SiO x /C anodes but also provides ideas to develop a high-performance adhesive technology for LIBs.