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Lithium (Li) metal anode has attracted tremendous attention for its highest capacity (3860 mAh g -1 ). Herein, we report that the formation of dead Li can be effectively suppressed through Li plating on porous lithiated graphite lamina (PLGL). A lithiophilic carbon layer was decorated on the lithiophobic basal plane of porous graphite lamina (PGL) with an industry-scalable slurry-coating strategy. Moreover, the higher delithiation potential of PLGL will ensure the complete stripping of the plated Li before its delithiation, thus dramatically enhancing the average Coulombic efficiency (ACE) of Li plating/stripping to 98.5% at a high Li plating/stripping capacity of 2 mAh cm -2 (∼1100 mAh g -1 ) at 2 mA cm -2 . Even at an ultrahigh current density of 4 mA cm -2 (with Li capacity of 4 mAh cm -2 (∼1900 mAh g -1 )), the ACE could still be maintained at 96.2% in an ordinary carbonate electrolyte.

Uncontrollable dendrite growth is one of the major problems that hinders the application of lithium (Li) metal anode in rechargeable Li batteries. Achieving uniform Li deposition is the key to tackle this intractable problem. Herein, we report the highly dispersed Cu 2 O nanoparticles (NPs) in situ anchored on partially reduced graphene oxide via a low-temperature pyrolysis process could serve as seeds for the Li metal deposition. The lithiophilic nature of Cu 2 O NPs reduces the overpotential of Li nucleation and relieves the electrode polarization, enabling uniform Li nucleation and smooth plating, thus effectively eliminating dendritic and dead Li. As a result, the resulted Li metal electrodes deliver a high Coulombic efficiency of 95.6% after 140 cycles at a current density of 2 mA cm -2 and a prolonged lifespan (800 h at 1 mA cm -2 ) for the symmetrical cell.

Lithium-sulfur (Li-S) batteries are seriously restrained by the shuttling effect of intermediary products and their further reduction on the anode surface. Considerable researches have been devoted to overcoming these issues by introducing carbon-based materials as the sulfur host or interlayer in the Li-S systems. Herein, we constructed a multifunctional interlayer on a separator by inserting Fe 3 O 4 nanoparticles (NPs) in a porous graphene (PG) film to immobilize polysulfides effectively. The porous structure of graphene was optimized by controlling the oxidation conditions for facilitating ion transfer. The polar Fe 3 O 4 NPs were employed to trap sulfur species via strong chemical interaction. By exploiting the PG-Fe 3 O 4 interlayer with optimal porous structure and component, the Li-S battery delivered a superior cycling performance and rate capability. The reversible discharge capacity could be maintained at 732 mAh g -1 after 500 cycles and 356 mAh g -1 after total 2000 cycles at 1 C with a final capacity retention of 49%. Moreover, a capacity of 589 mAh g -1 could also be maintained even at 2 C rate.

Three-dimensional graphene aerogel/TiO 2 /sulfur (GA/TiO 2 /S) composites are synthesized through a facile, one-pot hydrothermal route as the cathode for lithium-sulfur batteries. With a high sulfur content of 75.1 wt %, the conductive, highly porous composite electrode delivers a high discharge capacity of 512 mA h/g after 250 cycles at a current rate of 1 C with a low capacity decay of 0.128% per cycle. The excellent capacities and cyclic stability arise from several unique functional features of the cathode. (i) The conductive graphene aerogel framework ameliorates ion/electron transfer while accommodating the volume expansion induced during discharge, and (ii) TiO 2 nanoparticles play an important role in restricting the dissolution of polysulfides by chemical bonds with sulfur.

Although lithium-sulfur (Li-S) batteries deliver high specific energy densities, lots of intrinsic and fatal obstacles still restrict their practical application. Electrospun carbon nanofibers (CNFs) decorated with ultrafine TiO2 nanoparticles (CNF-T) were prepared and used as a multifunctional interlayer to suppress the volume expansion and shuttle effect of Li-S battery. With this strategy, the CNF network with abundant space and superior conductivity can accommodate and recycle the dissolved polysulfides for the bare sulfur cathode. Meanwhile, the ultrafine TiO2 nanoparticles on CNFs work as anchoring points to capture the polysulfides with the strong interaction, making the battery perform with remarkable and stable electrochemical properties. As a result, the Li-S battery with the CNF-T interlayer delivers an initial reversible capacity of 935 mA h g(-1) at 1 C with a capacity retention of 74.2% after 500 cycles. It is believed that this simple, low-cost and scalable method will definitely bring a novel perspective on the practical utilization of Li-S batteries.

The ability to enhance the specific capacity of Li4Ti5O12 (LTO) is of practical significance and offers the opportunity to increase the energy density of a full LTO-based battery. Widening the discharge cutoff voltage to 0 V is an effective way to increase the capacity of LTO at low current density. However, whether the specific capacity of LTO at large current rates can be enhanced remains largely unknown. Herein, intriguingly, we found that, when cycled down to 0 V (i.e., from 1.0-2.5 to 0-25 V), LTO exhibited greatly enhanced specific capacity at low rates (<5 C), while it showed a rapid capacity fading and a greatly increased charge/discharge potential gap at high rates (>10 C). The decreased lithium-ion diffusion caused by extra lithium-ion intercalation together with increased internal impedance significantly enhances the polarization and reduces the electrochemical reaction kinetics, which, in turn, hinders the lithiation reaction from LTO to Li7Ti5O12 and further to Li9Ti5O12.