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Li‐rich Mn‐based layered oxides (LRLOs) with ultrahigh specific capacities are promising cathode materials for high energy density lithium‐ion batteries. Nevertheless, severe irreversible oxygen release, structure degradation, capacity and voltage attenuation hinder their commercialization due to the uncontrollable oxygen redox chemistry originated from unhybridized O 2p orbitals. Herein, a strategy to generate bulk oxygen vacancies is proposed. And bulk oxygen vacancies are constructed by lowering the formation energy of oxygen vacancies in LRLOs via Gd‐doping. The energy level and the amount of unhybridized O 2p states are reduced to partly inhibit the oxygen redox activity. Surprisingly, the oxygen redox is not fully activated in the first cycle and is further activated in the second cycle. Moreover, the reduced oxygen redox activity significantly suppresses the oxygen release, lattice volume change, layered‐to‐spinel phase transition. As a result, the amount of oxygen gas release is reduced from 98.80 to ≈0 nmol mg−1 in the first cycle. Superior cycle stability of 90.4% capacity retention after 300 cycles and small voltage decay of only 1.013 mV per cycle are achieved. This study provides a valuable bulk oxygen vacancies strategy to regulate the unhybridized O 2p orbitals for designing high‐performance Li‐rich Mn‐based layered oxide cathode materials. [ABSTRACT FROM AUTHOR]

Li‐rich and Ni‐rich layered oxides as next‐generation high‐energy cathodes for lithium‐ion batteries (LIBs) possess the catalytic surface, which leads to intensive interfacial reactions, transition metal ion dissolution, gas generation, and ultimately hinders their applications at 4.7 V. Here, robust inorganic/organic/inorganic‐rich architecture cathode‐electrolyte interphase (CEI) and inorganic/organic‐rich architecture anode‐electrolyte interphase (AEI) with F‐, B‐, and P‐rich inorganic components through modulating the frontier molecular orbital energy levels of lithium salts are constructed. A ternary fluorinated lithium salts electrolyte (TLE) is formulated by mixing 0.5 m lithium difluoro(oxalato)borate, 0.2 m lithium difluorophosphate with 0.3 m lithium hexafluorophosphate. The obtained robust interphase effectively suppresses the adverse electrolyte oxidation and transition metal dissolution, significantly reduces the chemical attacks to AEI. Li‐rich Li1.2Mn0.58Ni0.08Co0.14O2 and Ni‐rich LiNi0.8Co0.1Mn0.1O2 in TLE exhibit high‐capacity retention of 83.3% after 200 cycles and 83.3% after 1000 cycles under 4.7 V, respectively. Moreover, TLE also shows excellent performances at 45 °C, demonstrating this inorganic rich interface successfully inhibits the more aggressive interface chemistry at high voltage and high temperature. This work suggests that the composition and structure of the electrode interface can be regulated by modulating the frontier molecular orbital energy levels of electrolyte components, so as to ensure the required performance of LIBs. [ABSTRACT FROM AUTHOR]

Li metal batteries have suffered from dendrite growth and its derived dead Li formation for a long time. A new lithium restoration method through the shuttling of redox mediators has been proposed recently. However, the side reaction of severe self‐discharge often occurs when some redox mediators are used. Here, a selection principle of redox mediators for reactivating dead Li in lithium metal batteries is put forward, which is able to reactivate the dead Li effectively and reduce the self‐discharge at the same time. Three redox mediators of ferrocene (Fc), 10‐methylphenothiazine (MPT), and thianthrene (Th) with different redox potentials are tested in LiFePO4|Cu anode‐free Li metal batteries to clarify the selection principle. Furthermore, 2,2,6,6‐tetramethylpiperidinooxy (TEMPO), which is speculated to be a suitable one for reactivating dead Li in lithium metal batteries, is verified. This work provides a universal selection principle of redox mediators and may boost its practical application in Li metal batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur/selenium batteries have attracted broad interest and achieved good performance using ether‐based electrolytes. However, when the ether‐based electrolytes are employed, Li–S/Se battery systems still have several inevitable drawbacks inhibiting their practical applications, such as intermediate product dissolution issues, and a dependency on a high content of electrolyte. Thus, it is urgent to pay attention to the electrochemical properties of SexSy cathodes in carbonate‐based electrolytes, which may avoid the above mentioned problems. In this work, a series of mesoporous carbon/SexSy (CMK‐3/SexSy) composites with covalent Se‐S bonds and different Se/S molar ratios are prepared and their working mechanism in carbonate‐based electrolytes is systematically investigated by combining experimental analysis and theoretical calculations. This work finds that the Se in the CMK‐3/SexSy cathode is beneficial for the transportation of Li+ ions and forms a thin cathode electrolyte interphase (CEI) during the discharge–charge process. Furthermore, S substitution in Se8 molecules can enhance the specific capacity and lower the bond breaking and lithiation energies. The optimal CMK‐3/SexSy cathode delivers outstanding performance with a high reversible capacity of 609 mA h g−1 at 1 A g−1 over 300 cycles. [ABSTRACT FROM AUTHOR]

The well‐known "shuttle effect" of the intermediate lithium polysulfides (LiPSs) and low sulfur utilization hinder the practical application of lithium–sulfur (Li–S) batteries. Herein, we describe a novel C60–S supramolecular complex with high‐density active sites for LiPS adsorption that was formed by a simple one‐step process as a cathode material for Li–S batteries. Benefiting from the cocrystal structure, 100 % of the C60 molecules in the complex can offer active sites to adsorb LiPSs and catalyze their conversion. Furthermore, the lithiated C60 cores promote internal ion transport inside the composite cathode. At a low electrolyte/sulfur ratio of 5 μL mg−1, the C60–S cathode with a sulfur loading of 4 mg cm−2 exhibited a high capacity of 809 mAh g−1 (3.2 mAh cm−2). The development of the C60–S supramolecular complex will inspire the invention of a new family of S/fullerenes as cathodes for high‐performance Li–S batteries and extend the application of fullerenes. [ABSTRACT FROM AUTHOR]

The well‐known "shuttle effect" of the intermediate lithium polysulfides (LiPSs) and low sulfur utilization hinder the practical application of lithium–sulfur (Li–S) batteries. Herein, we describe a novel C60–S supramolecular complex with high‐density active sites for LiPS adsorption that was formed by a simple one‐step process as a cathode material for Li–S batteries. Benefiting from the cocrystal structure, 100 % of the C60 molecules in the complex can offer active sites to adsorb LiPSs and catalyze their conversion. Furthermore, the lithiated C60 cores promote internal ion transport inside the composite cathode. At a low electrolyte/sulfur ratio of 5 μL mg−1, the C60–S cathode with a sulfur loading of 4 mg cm−2 exhibited a high capacity of 809 mAh g−1 (3.2 mAh cm−2). The development of the C60–S supramolecular complex will inspire the invention of a new family of S/fullerenes as cathodes for high‐performance Li–S batteries and extend the application of fullerenes. [ABSTRACT FROM AUTHOR]

Solid–solid reactions are very effective for solving the main challenges of lithium–sulfur (Li–S) batteries, such as the shuttle effect of polysulfides and the high dependence of electrolyte consumption. However, the low sulfur content and sluggish redox kinetics of such cathodes dramatically limit the practical energy density of Li–S batteries. Here a rationally designed hierarchical cathode to simultaneously solve above‐mentioned challenges is reported. With nanoscale sulfur as the core, selenium‐doped sulfurized polyacrylonitrile (PAN/S7Se) as the shell and micron‐scale secondary particle morphology, the proposed cathode realizes excellent solid–solid reaction kinetics in a commercial carbonate electrolyte under high active species loading and a relatively low electrolyte/sulfur ratio. Such an approach provides a promising solution toward practical lithium sulfur batteries. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries are promising next‐generation rechargeable batteries due to thier high energy density, low cost, and environmental friendliness. However, the extremely low electrical conductivity of sulfur and the dissolution of polysulfides limit their actual electrochemical performances, especially in the case of high sulfur mass loading. Here, a new strategy based on intrinsic point defects of materials is proposed to simultaneously enhance the electrical conductivity of active material and regulate the migration of polysulfides. Taking advantage of ultrathin and lightweight Bi2Te2.7Se0.3 (BTS) interlayers with high‐density antisite defects on the separator surface, the Li–S battery with BTS interlayer shows a capacity of 756 mAh g−1 at 2C and a low capacity decay rate of 0.1% over 300 cycles. The BTS interlayer can not only enhance the active material utilization but also improve capacity retention. The defect engineering strategy accompanied with facile method is promising for the development of advanced Li–S batteries for practical application. [ABSTRACT FROM AUTHOR]

Enabling Selenium-Rich SexSy Cathodes to Work in Carbonate-Based Electrolytes (Adv. Keywords: carbonate-based electrolytes; enhanced conductivity; mesoporous carbon; selenium-rich SexSy cathodes; solid-conversion mechanism EN carbonate-based electrolytes enhanced conductivity mesoporous carbon selenium-rich SexSy cathodes solid-conversion mechanism 1 1 1 01/10/22 20220101 NES 220101 B Carbonate-Based Electrolytes b In article number 2102832, Zhen Li, Yunhui Huang and co-workers prepare a series of mesoporous carbon/Se SB I x i sb S SB I y i sb composites with covalent Se-S bonds and different Se/S molar ratios and systematically investigate their working mechanism in carbonate-based electrolytes. Carbonate-based electrolytes, enhanced conductivity, mesoporous carbon, selenium-rich SexSy cathodes, solid-conversion mechanism. [Extracted from the article]

Ultrathin Conductive Interlayers: Ultrathin Conductive Interlayer with High-Density Antisite Defects for Advanced Lithium-Sulfur Batteries (Adv. Funct. Keywords: bismuth telluride; lithium-sulfur batteries; point defects; separator modification; ultrathin interlayers EN bismuth telluride lithium-sulfur batteries point defects separator modification ultrathin interlayers 1 1 1 01/15/21 20210111 NES 210111 In article number 2001201, Zhen Li, Yunhui Huang, and co-workers present an ultrathin, lightweight, and highly conductive Bi SB 2 sb Te SB 2.7 sb Se SB 0.3 sb interlayer on the separator surface that can not only enhance the capacity utilization of the sulfur electrode, but also improve the cycling stability due to the strong interaction between polysulfides and the intrinsic antisite defects. Bismuth telluride, lithium-sulfur batteries, point defects, separator modification, ultrathin interlayers. [Extracted from the article]

Using a solid‐state electrolyte (SSE) to stabilize the Li metal anode is widely considered a promising route to develop next‐generation high energy density lithium batteries. Here, a new polycrystalline aluminate‐based SSE (named Li–Al–O SSE) with good capability is introduced to protect Li metal. The SSE is formed on the Li metal surface via a chemical reaction between LiOH and triethylaluminum (TEAL) with the existence of LiTFSI‐based electrolyte. It is a continuous film that consists of polycrystalline LiAlO2, Li3AlO3, Al2O3, Li2CO3, LiF, and some organic compounds. Such Li–Al–O SSE possesses a room‐temperature ionic conductivity as high as 1.42 × 10−4 S cm−1. Meanwhile, it effectively protects the Li anode from the corrosion of H2O, O2, and organic solvent, and suppresses the growth of Li dendrite. With the protection of the Li–Al–O SSE, the cycle life of Li|Li symmetric cell and Li|O2 cell is substantially elongated, indicating that the SSE exhibits an excellent protective effect under both inert and oxidizing circumstances. [ABSTRACT FROM AUTHOR]

All‐solid‐state batteries are promising candidates for the next‐generation safer batteries. However, a number of obstacles have limited the practical application of all‐solid‐state Li batteries (ASSLBs), such as moderate ionic conductivity at room temperature. Here, unlike most of the previous approaches, superior performances of ASSLBs are achieved by greatly reducing the thickness of the solid‐state electrolyte (SSE), where ionic conductivity is no longer a limiting factor. The ultrathin SSE (7.5 µm) is developed by integrating the low‐cost polyethylene separator with polyethylene oxide (PEO)/Li‐salt (PPL). The ultrathin PPL shortens Li+ diffusion time and distance within the electrolyte, and provides sufficient Li+ conductance for batteries to operate at room temperature. The robust yet flexible polyethylene offers mechanical support for the soft PEO/Li‐salt, effectively preventing short‐circuits even under mechanical deformation. Various ASSLBs with PPL electrolyte show superior electrochemical performance. An initial capacity of 135 mAh g−1 at room temperature and the high‐rate capacity up to 10 C at 60 °C can be achieved in LiFePO4/PPL/Li batteries. The high‐energy‐density sulfur cathode and MoS2 anode employing PPL electrolyte also realize remarkable performance. Moreover, the ASSLB can be assembled by a facile process, which can be easily scaled up to mass production. [ABSTRACT FROM AUTHOR]

Lithium metal is widely studied as the "crown jewel" of potential anode materials due to its high specific capacity and low redox potential. Unfortunately, the Li dendrite growth limits its commercialization. Previous research has revealed that the uniform Li‐ion flux on electrode surface plays a vital role in achieving homogeneous Li deposition. In this work, a new strategy is developed by introducing a multifunctional Li‐ion pump to improve the homogenous distribution of Li ions. Via coating a β‐phase of poly(vinylidene fluoride) (β‐PF) film on Cu foil (Cu@β‐PF), a piezoelectric potential across such film is established near the electrode surface because of its piezoelectric property, which serves as a driving force to regulate the migration of Li ions across the film. As a result, uniform Li‐ion distribution is attained, and the Cu@β‐PF shows coulombic efficiency around 99% throughout 200 cycles. Meanwhile, the lithium‐sulfur full cell paired with Li‐Cu@β‐PF anode exhibits excellent performance. This facile strategy via regulating the Li‐ion migration provides a new perspective for safe and reliable Li metal anode. [ABSTRACT FROM AUTHOR]

Among all the possible anode materials for next‐generation rechargeable batteries, lithium (Li) metal stands out from the crowd for its high specific capacity and low redox potential. Unfortunately, the issues caused by Li dendrites limit the commercialization of the batteries based on Li metal anodes. Research in recent years has proved that the Li dendrites cannot be completely eliminated. Inspired by the Chinese legend, "King Yu Tamed the Flood," the new strategy of combing dredge and block, to control the diversion of Li ions is proposed. Via Au modification on one side of the carbon fibers matrix (CFs@Au), selective deposition of Li ions on the back side of the current collector is successfully achieved. This is distant from the separator, and hence improves the safety effectively. As a result, the Coulombic efficiency of the CFs@Au–Li anode remains 99.2% throughout 400 cycles. What is more, the Li–S full cell paired with the composite anode also exhibits outstanding performance, even with limited Li. This backside‐deposition strategy provides new insight into safe Li metal anode design for high energy density battery systems such as Li–S and Li–O2. Inspired by the legend, "King Yu Tamed the Flood," the new strategy of combing dredge and block is proposed to control diversion of Li‐ions, realizing Li‐ions deposition in the opposite direction away from the separator. Even after 400 cycles, the Coulombic efficiency still remains 99.2% and the Li–S full cell also exhibits good performance with limited Li amount. [ABSTRACT FROM AUTHOR]