Substituent effects on the electronic structures and nonlinear optical properties of Li-doped nano-carbon bowl

A series of Li-corannulene-(NH₂)_n and Li-corannulene-(NO₂)_n (n = 1, 2, 5) compounds have been theoretically designed and investigated using density functional theory. In this work, two models are systematically investigated to explore the important factors for enhancing the static first hyperpolarizability by introducing the substitution group. It is revealed that energy gaps (E_gap) between highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) of all compounds are in the range of 4.149–4.934 eV. Different DFT methods are adopted to calculate polarizabilities and the first hyperpolarizabilities of Li-corannulene-(NH₂)_n and Li-corannulene-(NO₂)_n (n = 1, 2, 5) compounds. It is revealed that polarizability values of the systems increase with increasing number of NH₂/NO₂ substitution group. Moreover, it is found that the first hyperpolarizabilities of Li-corannulene-(NO₂)_n are larger than those of Li-corannulene-(NH₂)_n, which can be attributed to the lower transition energies. In contrast to the NH₂ substitution group, NO₂ substitution group can be more powerful in increasing the first hyperpolarizability of Li-doped corannulene. We hope that this study can provide a new idea for designing nonlinear optical materials using the NH₂ and NO₂ groups.     

(Super)alkali atoms interacting with the σ electron cloud: a novel interaction mode triggers large nonlinear optical response of M@P4 and M@C3H6 (M=Li, Na, K and Li3O)

Under high-level ab initio calculations, the geometrical structures and nonlinear optical properties of M@P₄ (M=Li, Na, K and Li₃O) and M@C₃H₆ (M=Li and Li₃O) were investigated; all were found to exhibit considerable first hyperpolarizabilities (18110, 1440, 22490, 50487, 2757 and 31776 au, respectively). The computational results revealed that when doping the (super)alkali atom M into the tetrahedral P₄ molecule, the original dual spherical aromaticity of the P₄ moiety is broken and new σ electron cloud is formed on the face of P₄ part interacting with the M atom. It was found that interaction of the (super)alkali atom with the σ electron cloud is a novel mode to produce diffuse excess electrons effectively to achieve a considerable β ₀ value. Further, beyond the alkali atom, employing the superalkali unit can be a more effective approach to significantly enhance the first hyperpolarizability of the systems, due to the much lower vertical ionization potential. These results were further supported by the case of the (super)alkali atom interacting with the cyclopropane C₃H₆ molecule with its typical σ aromatic electron cloud. Moreover, the β ₀ values of the M@P₄ series are nonmonotonic dependent on alkali atomic number, namely, 1440 au (M?=?Na)?<?18110 au (Li)?<?22490 au (K), inferring that the distance between the alkali atom and the interacting surface with the σ electron cloud in P₄ is a crucial geometrical factor in determining their first hyperpolarizabilities. These intriguing findings will be advantageous for promoting the design of novel high-performance nonlinear optical materials.

The effects of external electric field: creating non-zero first hyperpolarizability for centrosymmetric benzene and strongly enhancing first hyperpolarizability for non-centrosymmetric edge-modified graphene ribbon H2N-(3,3)ZGNR-NO2

How to generate a non-zero first hyperpolarizability for a centrosymmetric molecule is a challenging question. In this paper, an external (pump) electric field is used to make a centrosymmetric benzene molecule generate a non-zero value of the electric field induced first hyperpolarizability (β ^F ). This comes from the centrosymmetry breaking of electron cloud. Two interesting rules are exhibited. (1) β ^F is anisotropic for different directional fields (F _i, i?=?X, Y, Z). (2) The field dependence of β ^F is a non-monotonic function, and an optimum external electric field causes the maximum value of β ^F . The largest first hyperpolarizability β ^F reaches the considerable level of 3.9?×?10⁵ a.u. under F _Y?=?330?×?10^?4 a.u. for benzene. The external electric field effects on non-centrosymmetric edge-modified graphene ribbon H₂N-(3,3)ZGNR-NO₂ was also studied in this work. The first hyperpolarizability reaches as much as 2.1?×?10⁷ a.u. under F _X?=?600?×?10^?4 a.u. for H₂N-(3,3)ZGNR-NO₂. We show that the external electric field can not only create a non-zero first hyperpolarizability for centrosymmetric molecule, but also remarkably enhance the first hyperpolarizability for a non-centrosymmetric molecule.     

The encapsulated lithium effect on the first hyperpolarizability of C<Subscript>60</Subscript>Cl<Subscript>2</Subscript> and C<Subscript>60</Subscript>F<Subscript>2</Subscript>

In this paper, we report a study on the structure and first hyperpolarizability of C₆₀Cl₂ and C₆₀F₂. The calculation results show that the first hyperpolarizabilities of C₆₀Cl₂ and C₆₀F₂ were 172 au and 249 au, respectively. Compared with the fullerenes, the first hyperpolarizability of C₆₀Cl₂ increased from 0 au to 172 au, while the first hyperpolarizability of C₆₀F₂ increased from 0 au to 249 au. In order to further increase the first hyperpolarizability of C₆₀Cl₂ and C₆₀F₂, Li@C₆₀Cl₂ and Li@C₆₀F₂ were obtained by introducing a lithium atom to C₆₀Cl₂ and C₆₀F₂. The first hyperpolarizabilities of Li@C₆₀Cl₂ and Li@C₆₀F₂ were 2589 au and 985 au, representing a 15-fold and 3.9-fold increase, respectively, over those of C₆₀Cl₂ and C₆₀F₂. The transition energies of four molecules (C₆₀Cl₂, Li@C₆₀Cl₂, C₆₀F₂, Li@C₆₀F₂) were calculated, and were found to be 0.17866 au, 0.05229 au, 0.18385 au, and 0.05212 au, respectively. A two-level model explains why the first hyperpolarizability increases for Li@C₆₀Cl₂ and Li@C₆₀F₂.     

In Situ Generation of Few‐Layer Graphene Coatings on SnO2‐SiC Core‐Shell Nanoparticles for High‐Performance Lithium‐Ion Storage

A simple ball‐milling method is used to synthesize a tin oxide‐silicon carbide/few‐layer graphene core‐shell structure in which nanometer‐sized SnO₂ particles are uniformly dispersed on a supporting SiC core and encapsulated with few‐layer graphene coatings by in situ mechanical peeling. The SnO₂‐SiC/G nanocomposite material delivers a high reversible capacity of 810 mA h g^?1 and 83% capacity retention over 150 charge/discharge cycles between 1.5 and 0.01 V at a rate of 0.1 A g^?1. A high reversible capacity of 425 mA h g^?1 also can be obtained at a rate of 2 A g^?1. When discharged (Li extraction) to a higher potential at 3.0 V (vs. Li/Li⁺), the SnO₂‐SiC/G nanocomposite material delivers a reversible capacity of 1451 mA h g^?1 (based on the SnO₂ mass), which corresponds to 97% of the expected theoretical capacity (1494 mA h g^?1, 8.4 equivalent of lithium per SnO₂), and exhibits good cyclability. This result suggests that the core‐shell nanostructure can achieve a completely reversible transformation from Li_4.4Sn to SnO₂ during discharging (i.e., Li extraction by dealloying and a reversible conversion reaction, generating 8.4 electrons). This suggests that simple mechanical milling can be a powerful approach to improve the stability of high‐performance electrode materials involving structural conversion and transformation.     

High‐Performance Lithium‐Sulfur Batteries with a Self‐Supported, 3D Li2S‐Doped Graphene Aerogel Cathodes

Lithium‐sulfur (Li‐S) batteries are being considered as the next‐generation high‐energy‐storage system due to their high theoretical energy density. However, the use of a lithium‐metal anode poses serious safety concerns due to lithium dendrite formation, which causes short‐circuiting, and possible explosions of the cell. One feasible way to address this issue is to pair a fully lithiated lithium sulfide (Li₂S) cathode with lithium metal‐free anodes. However, bulk Li₂S particles face the challenges of having a large activation barrier during the initial charge, low active‐material utilization, poor electrical conductivity, and fast capacity fade, preventing their practical utility. Here, the development of a self‐supported, high capacity, long‐life cathode material is presented for Li‐S batteries by coating Li₂S onto doped graphene aerogels via a simple liquid infiltration–evaporation coating method. The resultant cathodes are able to lower the initial charge voltage barrier and attain a high specific capacity, good rate capability, and excellent cycling stability. The improved performance can be attributed to the (i) cross‐linked, porous graphene network enabling fast electron/ion transfer, (ii) coated Li₂S on graphene with high utilization and a reduced energy barrier, and (iii) doped heteroatoms with a strong binding affinity toward Li₂S/lithium polysulfides with reduced polysulfide dissolution based on first‐principles calculations.     

Li2O:Li–Mn–O Disordered Rock‐Salt Nanocomposites as Cathode Prelithiation Additives for High‐Energy Density Li‐Ion Batteries

The irreversible loss of lithium from the cathode material during the first cycles of rechargeable Li‐ion batteries notably reduces the overall cell capacity. Here, a new family of sacrificial cathode additives based on Li₂O:Li_2/3Mn_1/3O_5/6 composites synthesized by mechanochemical alloying is reported. These nanocomposites display record (but irreversible) capacities within the Li–Mn–O systems studied, of up to 1157 mAh g^?1, which represents an increase of over 300% of the originally reported capacity in Li_2/3Mn_1/3O_5/6 disordered rock salts. Such a high irreversible capacity is achieved by the reaction between Li₂O and Li_2/3Mn_1/3O_5/6 during the first charge, where electrochemically active Li₂O acts as a Li⁺ donor. A 13% increase of the LiFePO₄ and LiCoO₂ first charge gravimetric capacities is demonstrated by the addition of only 2 wt% of the nanosized composite in the cathode mixture. This result shows the great potential of these newly discovered sacrificial additives to counteract initial losses of Li⁺ ions and improve battery performance.     

Effects of the adsorption of alkali metal oxides on the electronic,optical, and thermodynamic properties of the Mg<Subscript>12</Subscript>O<Subscript>12</Subscript>nanocage: a density functional theory study

The effect of alkali metal oxides M _n O (M?=?Li, Na, K; n?=?2, 3, 4) on the geometric, electronic, and linear and nonlinear optical properties of the Mg₁₂O₁₂ nanocage was investigated by density-functional-based methods. According to the computational results, these alkali metal oxides are adsorbed on the Mg₁₂O₁₂ nanocage because this adsorption reduces its energy gap. The static first hyperpolarizability (β ₀) of the nanocage is dramatically increased in the presence of the alkali metal oxides, with the greatest increase seen in the presence of the superalkalis (i.e., M₃O; M?=?Li, Na, and K). The highest first hyperpolarizability (β ₀?≈?600,000 a.u.) was calculated for K₃O@Mg₁₂O₁₂, which was considerably more than that for Mg₁₂O₁₂. The thermodynamic properties and relative stabilities of these inorganic compounds are discussed.

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Graphical Abstract Optimized structure and DOS spectrum of K₃O(e@Mg₁₂O₁₂)

     

Metal Sulfide‐Decorated Carbon Sponge as a Highly Efficient Electrocatalyst and Absorbant for Polysulfide in High‐Loading Li2S Batteries

Owing to its high theoretical specific capacity (1166 mA h g^?1) and particularly its advantage to be paired with a lithium‐metal‐free anode, lithium sulfide (Li₂S) is regarded as a much safer cathode for next‐generation advanced lithium–sulfur (Li–S) batteries. However, the low conductivity of Li₂S and particularly the severe “polysulfide shuttle” of lithium polysulfide (LiPS) dramatically hinder their practical application in Li–S batteries. To address such issues, herein a bifuctional 3D metal sulfide‐decorated carbon sponge (3DTSC), which is constructed by 1D carbon nanowires cross‐linked with 2D graphene nanosheets with high conductivity and polar 0D metal sulfide nanodots with efficient electrocatalytic activity and strong chemical adsorption capability for LiPSs, is presented. Benefiting from the well‐designed multiscale, multidimensional 3D porous nanoarchitecture with high conductivity, and efficient electrocatalytic and absorption ability, the 3DTSC significantly mitigates LiPS shuttle, improves the utilization of Li₂S, and facilitates the transport of electrons and ions. As a result, even with a high Li₂S loading of 8 mg cm^?2, the freestanding 3DTSC‐Li₂S cathode without a polymer binder and metallic current collector delivers outstanding electrochemical performance with a high areal capacity of 8.44 mA h cm^?2.     

A Novel Surface Treatment Method and New Insight into Discharge Voltage Deterioration for High‐Performance 0.4Li2MnO3–0.6LiNi1/3Co1/3Mn1/3O2 Cathode Materials

The Li‐rich cathode materials have been considered as one of the most promising cathodes for high energy Li‐ion batteries. However, realization of these materials for use in Li‐ion batteries is currently limited by their intrinsic problems. To overcome this barrier, a new surface treatment concept is proposed in which a hybrid surface layer composed of a reduced graphene oxide (rGO) coating and a chemically activated layer is created. A few layers of GO are first coated on the surface of the Li‐rich cathode material, followed by a hydrazine treatment to produce the reducing agent of GO and the chemical activator of the Li₂MnO₃ phase. Compared to previous studies, this surface treatment provides substantially improved electrochemical performance in terms of initial Coulombic effiency and retention of discharge voltage. As a result, the surface‐treated 0.4Li­₂MnO_3–0.6LiNi_1/3Co_1/3Mn_1/3O₂ exhibits a high capacity efficiency of 99.5% during the first cycle a the discharge capacity of 250 mAh g^?1 (2.0–4.6 V under 0.1C), 94.6% discharge voltage retention during 100 cycles (1C) and the superior capacity retention of 60% at 12C at 24 °C.     

Interaction between an icosahedron Li13 cluster and a graphene layer doped with a hydrogen atom

It is known that graphene reacts with atomic hydrogen to form a hydrogenated sheet of graphene. In order to understand the nature of the interaction between hydrogen and lithium in hydrogenated samples, we have carried out first principle calculations. Density functional theory and molecular dynamics were used to study the interaction between an icosahedron Li₁₃ cluster, and a graphene layer doped with a hydrogen atom. It was found that a hydrogen atom is levitated from the graphene layer and absorbed into the cluster of Li at 300?K and atmospheric pressure, with a binding energy far exceeding that of the adsorption energy of a hydrogen atom on the graphene layer.     

Atomic Structure of Li2MnO3 after Partial Delithiation and Re‐Lithiation

Li₂MnO₃ is the parent compound of the well‐studied Li‐rich Mn‐based cathode materials xLi₂MnO₃·(1‐x)LiMO₂ for high‐energy‐density Li‐ion batteries. Li₂MnO₃ has a very high theoretical capacity of 458 mA h g^?1 for extracting 2 Li. However, the delithiation and lithiation behaviors and the corresponding structure evolution mechanism in both Li₂MnO₃ and Li‐rich Mn‐based cathode materials are still not very clear. In this research, the atomic structures of Li₂MnO₃ before and after partial delithiation and re‐lithiation are observed with spherical aberration‐corrected scanning transmission electron microscopy (STEM). All atoms in Li₂MnO₃ can be visualized directly in annular bright‐field images. It is confirmed accordingly that the lithium can be extracted from the LiMn₂ planes and some manganese atoms can migrate into the Li layer after electrochemical delithiation. In addition, the manganese atoms can move reversibly in the (001) plane when ca. 18.6% lithium is extracted and 12.4% lithium is re‐inserted. LiMnO₂ domains are also observed in some areas in Li_1.63MnO₃ at the first cycle. As for the position and occupancy of oxygen, no significant difference is found between Li_1.63MnO₃ and Li₂MnO₃.     

Structural and Chemical Evolution of the Layered Li‐Excess LixMnO3 as a Function of Li Content from First‐Principles Calculations

Li₂MnO₃ is a critical component in the family of “Li‐excess” materials, which are attracting attention as advanced cathode materials for Li‐ion batteries. Here, first‐principle calculations are presented to investigate the electrochemical activity and structural stability of stoichiometric Li_xMnO₃ (0 ≤ x ≤ 2) as a function of Li content. The Li₂MnO₃ structure is electrochemically activated above 4.5 V on delithiation and charge neutrality in the bulk of the material is mainly maintained by the oxidization of a portion of the oxygen ions from O^2? to O^1?. While oxygen vacancy formation is found to be thermodynamically favorable for x < 1, the activation barriers for O^2? and O^1? migration remain high throughout the Li com­position range, impeding oxygen release from the bulk of the compound. Defect layered structures become thermodynamically favorable at lower Li content (x < 1), indicating a tendency towards the spinel‐like structure transformation. A critical phase transformation path for forming nuclei of spinel‐like domains within the matrix of the original layered structure is proposed. Formation of defect layered structures during the first charge is shown to manifest in a depression of the voltage profile on the first discharge, providing one possible explanation for the observed voltage fade of the Li‐excess materials.     

High‐Performance All‐Solid‐State Lithium–Sulfur Batteries Enabled by Amorphous Sulfur‐Coated Reduced Graphene Oxide Cathodes

Safety and the polysulfide shuttle reaction are two major challenges for liquid electrolyte lithium–sulfur (Li–S) batteries. Although use of solid‐state electrolytes can overcome these two challenges, it also brings new challenges by increasing the interface resistance and stress/strain. In this work, the interface resistance and stress/strain of sulfur cathodes are significantly reduced by conformal coating ≈2 nm sulfur (S) onto reduced graphene oxide (rGO). An Li–S full cell consisting of an rGO@S‐Li₁₀GeP₂S₁₂‐acetylene black (AB) composite cathode is evaluated. At 60 °C, the all‐solid‐state Li–S cell demonstrates a similar electrochemical performance as in liquid organic electrolyte, with high rate capacities of 1525.6, 1384.5, 1336.3, 903.2, 502.6, and 204.7 mA h g^?1 at 0.05, 0.1, 0.5, 1.0, 2.0, and 5.0 C, respectively. It can maintain a high and reversible capacity of 830 mA h g^?1 at 1.0 C for 750 cycles. The uniform distribution of the rGO@S nanocomposite in the Li₁₀GeP₂S₁₂‐AB matrix generates uniform volume changes during lithiation/delithiation, significantly reducing the stress/strain, thus extending the cycle life. Minimization of the stress/strain of solid cells is the key for a long cycle life of all‐solid‐state Li–S batteries.     

Polysulfide‐Shuttle Control in Lithium‐Sulfur Batteries with a Chemically/Electrochemically Compatible NaSICON‐Type Solid Electrolyte

A NaSICON‐type Li⁺‐ion conductive membrane with a formula of Li_{1+ x} Y _x Zr_{2? x} (PO₄)₃ (LYZP) (x = 0–0.15) has been explored as a solid‐electrolyte/separator to suppress polysulfide‐crossover in lithium‐sulfur (Li‐S) batteries. The LYZP membrane with a reasonable Li⁺‐ion conductivity shows both favorable chemical compatibility with the lithium polysulfide species and exhibits good electrochemical stability under the operating conditions of the Li‐S batteries. Through an integration of the LYZP solid electrolyte with the liquid electrolyte, the hybrid Li‐S batteries show greatly enhanced cyclability in contrast to the conventional Li‐S batteries with the porous polymer (e.g., Celgard) separator. At a rate of C/5, the hybrid Li ||LYZP|| Li₂S₆ batteries developed in this study (with a Li‐metal anode, a liquid/LYZP hybrid electrolyte, and a dissolved lithium polysulfide cathode) delivers an initial discharge capacity of ≈1000 mA h g^?1 (based on the active sulfur material) and retains ≈90% of the initial capacity after 150 cycles with a low capacity fade‐rate of <0.07% per cycle.     

Structural Changes in Li2MnO3 Cathode Material for Li‐Ion Batteries

Structural changes in Li₂MnO₃ cathode material for rechargeable Li‐ion batteries are investigated during the first and 33^rd cycles. It is found that both the participation of oxygen anions in redox processes and Li⁺‐H⁺ exchange play an important role in the electrochemistry of Li₂MnO₃. During activation, oxygen removal from the material along with Li gives rise to the formation of a layered MnO₂‐type structure, while the presence of protons in the interslab region, as a result of electrolyte oxidation and Li⁺‐H⁺ exchange, alters the stacking sequence of oxygen layers. Li re‐insertion by exchanging already present protons reverts the stacking sequence of oxygen layers. The re‐lithiated structure closely resembles the parent Li₂MnO₃, except that it contains less Li and O. Mn⁴⁺ ions remain electrochemically inactive at all times. Irreversible oxygen release occurs only during activation of the material in the first cycle. During subsequent cycles, electrochemical processes seem to involve unusual redox processes of oxygen anions of active material along with the repetitive, irreversible oxidation of electrolyte species. The deteriorating electrochemical performance of Li₂MnO₃ upon cycling is attributed to the structural degradation caused by repetitive shearing of oxygen layers.     

Understanding the Rate Capability of High‐Energy‐Density Li‐Rich Layered Li1.2Ni0.15Co0.1Mn0.55O2 Cathode Materials

The high‐energy‐density, Li‐rich layered materials, i.e., xLiMO₂(1‐x)Li₂MnO₃, are promising candidate cathode materials for electric energy storage in plug‐in hybrid electric vehicles (PHEVs) and electric vehicles (EVs). The relatively low rate capability is one of the major problems that need to be resolved for these materials. To gain insight into the key factors that limit the rate capability, in situ X‐ray absorption spectroscopy (XAS) and X‐ray diffraction (XRD) studies of the cathode material, Li_1.2Ni_0.15Co_0.1Mn_0.55O₂ [0.5Li(Ni_0.375Co_0.25 Mn_0.375)O₂·0.5Li₂MnO₃], are carried out. The partial capacity contributed by different structural components and transition metal elements is elucidated and correlated with local structure changes. The characteristic reaction kinetics for each element are identified using a novel time‐resolved XAS technique. Direct experimental evidence is obtained showing that Mn sites have much poorer reaction kinetics both before and after the initial activation of Li₂MnO₃, compared to Ni and Co. These results indicate that Li₂MnO₃ may be the key component that limits the rate capability of Li‐rich layered materials and provide guidance for designing Li‐rich layered materials with the desired balance of energy density and rate capability for different applications.     

Carbon‐Coated Li3Nd3W2O12: A High Power and Low‐Voltage Insertion Anode with Exceptional Cycleability for Li‐Ion Batteries

The synthesis of carbon‐coated Li₃Nd₃W₂O₁₂ (C‐Li₃Nd₃W₂O₁₂), a low voltage insertion anode (0.3 V vs. Li) for a Li‐ion battery, is reported to exhibit extraordinary performance. The low voltage reversible insertion provides an increase in the energy density of Li‐ion power packs. For instance, C‐Li₃Nd₃W₂O₁₂ delivered an energy density of ≈390 Wh kg^?1 (based on cathode mass loading) when coupled with an LiMn₂O₄ cathode with an operating potential of 3.4 V. Furthermore, excellent cycling profiles are observed for C‐Li₃Nd₃W₂O₁₂ anodes both in half and full‐cell configurations. The full‐cell is capable of delivering very stable cycling profiles at high current rates (e.g., 2 C), which clearly suggests the high power capability of such garnet‐type anodes.     

A Hybrid Mg2+/Li+ Battery Based on Interlayer‐Expanded MoS2/Graphene Cathode

The hybrid Mg²⁺/Li⁺ battery (MLIB) is a very promising energy storage technology that combines the advantage of the Li and Mg electrochemistry. However, previous research has shown that the battery performance is limited due to the strong dependence on the Li content in the dual Mg²⁺/Li⁺ electrolyte. This limitation can be circumvented by significantly improving the diffusion kinetics of Mg²⁺ in the electrode, so that both Li⁺ and Mg²⁺ ions can be utilized as charge carriers. Herein, a free‐standing interlayer expanded MoS₂/graphene composite (E‐MG) is demonstrated as a cathode for MLIB. The key advantage of this cathode is to enable the efficient intercalation of both Mg²⁺ and Li⁺. The E‐MG electrode displays a reversible capacity of ≈300 mA h g^?1 at 20 mA g^?1 in an MLIB cell, corresponding to a specific energy density up to ≈316.9 W h kg^?1, which is comparable to that of the state‐of‐the‐art Li‐ion batteries (LIBs) and has no dendrite formation. The composite electrode is stable against cycling with a coulombic efficiency close to 100% at 500 mA g^?1. This new electrode design represents a significant step forward for building a safe and high‐density electrochemical energy storage system.     

Tailored Reaction Route by Micropore Confinement for Li–S Batteries Operating under Lean Electrolyte Conditions

Lithium‐sulfur (Li–S) batteries are one of the most promising alternative energy storage systems beyond Li‐ion batteries. However, the sluggish kinetics of the nucleation and growth of the solid discharge product of Li₂S/Li₂S₂ in the lower discharge plateau has been recently identified as a critical hurdle for attaining high specific capacity in Li–S batteries with high sulfur loadings under lean electrolyte conditions. Herein, a new strategy of breaking the charge‐transport bottleneck by successful generation of experimentally verified stable Li₂S₂ and a reservoir of quasi‐solid lithium polysulfides within the micropores of activated carbon fiber cloth as a high‐sulfur‐loading host is proposed. The developed Li–S cell is capable of delivering a highly sustainable areal capacity of 6.0 mAh cm^?2 under lower electrolyte to sulfur ratios (<3.0 mL_E g_S^?1). Micropore confinement leads to generation of solid Li₂S₂ that enables high utilization of the entire electroactive area by its inherent self‐healing capacity. This strategy opens a new avenue for rational material designs for Li–S batteries under lean electrolyte condition.