The structures and components of solid electrolyte interphase (SEI) are extremely important to influence the performance of full cells, which is determined by the formulation of electrolyte used. However, it is still challenging to control the formation of high‐quality SEI from structures to components. Herein, we designed bisfluoroacetamide (BFA) as the electrolyte additive for the construction of a gradient solid electrolyte interphase (SEI) structure that consists of a lithophilic surface with C−F bonds to uniformly capture Li ions and a LiF‐rich bottom layer to guide the rapid transportation of Li ions, endowing the homogeneous deposition of Li ions. Moreover, the BFA molecule changes the Li+ solvation structure by reducing free solvents in electrolyte to improve the antioxidant properties of electrolyte and prevent the extensive degradation of electrolyte on the cathode surface, which can make a superior cathode electrolyte interphase (CEI) with high‐content LiF.

Lithium (Li) metal battery is considered the most promising next‐generation battery due to its low potential and high theoretical capacity. However, Li dendrite growth causes serious safety problems. Herein, the 15‐Crown‐5 (15‐C‐5) is reported as an electrolyte additive based on solvation shell regulation. The strong complex effect between Li+ ion and 15‐C‐5 can reduce the concentration of Li ions on the electrode surface, thus changing the nucleation, and repressing the growth of Li dendrites in the plating process. Significantly, the strong coordination of Li+/15‐C‐5 would be able to make them aggregate around the Li crystal surface, which could form a protective layer and favor the formation of a smooth and dense solid electrolyte interphase with high toughness and Li+ ion conductivity. Therefore, the electrolyte system with 2.0 wt% 15‐C‐5 achieves excellent electrochemical performance with 170 cycles at 1.0 mA cm−2 with capacity of 0.5 mA h cm−2 in symmetric Li|Li cells. The obviously enhanced cycle and rate performance are also achieved in Li|LiNi0.6Co0.2Mn0.2O2 (NCM622) full cells. The 15‐C‐5 demonstrates to be a promising additive for the electrolytes toward safe and efficient Li metal batteries.

The structure and components of solid electrolyte interphase (SEI) is crucial to direct the growth of lithium particles. However, it is hard to have control over them. Herein, an SEI that shares the properties of Li2CO3‐rich and LiF‐rich types is realized by using different fluorine phenylphospines, and constructing a Li2CO3/LiF‐rich heterostructured SEI by using tris(4‐fluorophenyl)phosphine (TFPP) as the electrolyte additive. The well‐balanced SEI formed in TFPP‐containing electrolyte has the fast Li+ transport kinetics of Li2CO3, good electron insulator capability of LiF, and strong affinity toward Li+. It can effectively guarantee fast, uniform Li+ flux through the SEI while preventing electrons from the Li anode entering into SEI, and thus realizes uniform and dense Li deposition at the SEI/Li interface. As expected, the Li anode with TFPP‐containing electrolyte achieves a stable Li plating/stripping over 400 h at 1mA cm−2 while the full cell with a high‐voltage LiNi0.6Co0.2Mn0.2O2 cathode also enables long‐term stability with a capacity retention (87.8% after 200 cycles) at 0.1 A g−1 and excellent rate performance.

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The safety and electrochemical performance of rechargeable lithium‐metal batteries (LMBs) are primarily influenced by the additives in the organic liquid electrolytes. However, multi‐functional additives are still rarely reported. Herein, we proposed heptafluorobutyric anhydride (HFA) as a qua‐functional additive to optimize the composition and structure of the solid electrolyte interphase (SEI) at the electrode/electrolyte interface. The reduction/oxidation decomposition of the fluorine‐rich HFA facilitate uniform inorganic‐rich SEI and compact cathode electrolyte interphase (CEI) formation, which enables stable lithium plating during charge and suppresses the dissolution of transition‐metal ions. Moreover, HFA optimizes the Li‐ion solvation for stable Li plating/stripping and serves as the surfactant to enhance the wettability of the separator by the electrolyte to increase Li‐ion flux. The symmetric Li∥Li cell with 1.0 wt % HFA electrolyte had an excellent cycling performance over 340 h at 1.0 mA cm−2 with a capacity of 0.5 mAh cm−2 while the Li∥NCM622 cell maintained high capacity retention after 250 cycles and outstanding rate performance even at 15 C.

Energy storage and conversion have attained significant interest owing to its important applications that reduce COi emission through employing green energy. Sorne promising technologies are included metal air batteries, metal sulfur batteries, met al ion batteries, electrochemical ca pacitors, etc. Here, metal elements are involved with lithium, sodium, and magnesium For these devices, electrode materials are of importance to obtain high performance. Two dimensional (2D) materials are a large kind of layered structured materials with promising future as energy storage materials, which include graphene, black phosporus, MXenes , covalent organic frameworks ( COFs ), 2D oxides, 2D chalcogenides, and ot hers. Great progress has been achieved to go ahead for 2D materials in energy storage and conversion. More researchers will j oin in this res earch field. Under the background, it has motivated us to c ontribute with a roadmap on 'two dimensional materials for energy storage and conversion.

Electrolyte additives play important roles in suppressing lithium dendrite growth and improving the electrochemical performance of long‐life lithium metal batteries (LMBs), however, it is still challenging to design individual additive for adjusting the solid electrolyte interphase (SEI) components and changing lithium ion solvation sheath in the electrolyte at the same time for optimizing electrochemical performance. Herein, alkyl‐triphenyl‐phosphonium bromides (alkyl‐TPPB) are designed as the electrolyte additive to enhance the stability of metallic Li anode under the guidance of multi‐factor principle for electrolyte additive molecule design (EDMD). Both alkyl‐TPP cations and Br− anions produce positive influences on suppressing Li dendrite growth and stabilizing the unstable interphase between metallic Li anode/electrolyte. As expected, the optimized solvation sheath structure, and the stable SEI suppress Li dendrite growth. As a result, the Li||Li4Ti5O12 cell reveals a long stable life over 1000 cycles with high Coulombic efficiency (99.9%). This work provides an insight on stabilizing SEI and optimizing solvation sheath structure with novel approach to develop long‐term stability and safety LMBs.

A novel electrode material of FeS2microspheres anchoring on graphene aerogel by C–N, Si–O bonds was constructed. This well-designed composite exhibited excellent rate and cyclic performances for sodium ion batteries.