Amide‐Functional, Li₃N/LiF‐Rich Heterostructured Electrode Electrolyte Interphases for 4.6 V Li||LiCoO₂ Batteries

Abstract

Enhancing the charge cut‐off voltage of LiCoO2 at 4.6 V can improve the battery density, however, structural instability is a critical challenge (e.g., electrolyte decomposition, Co dissolution, and structural phase transition). Here, robust electrode electrolyte interphases (EEIs) with the high Li+ conductivity offered by polar amide groups and a Li3N/LiF heterostructure is constructed. 3‐(trifluoromethyl) phenyl isocyanate (3‐TPIC) is rationally designed as an electrolyte additive for sustaining a 4.6 V Li||LiCoO2 battery with such CEI, which can effectively address the challenge of structural instability. The polar amide group can achieve Li+ de‐solvation and increase Li+ transport. Li3N/LiF heterostructure in the cathode electrolyte interphase (CEI) can speed up the Li+ insertion/extraction for improving Coulombic efficiency and weakening polarization of LiCoO2 at 4.6 V. In addition, the solid electrolyte interphase (SEI) with a similar structure on the Li anode surface contributes to the uniform Li deposition for suppressing the Li dendrite growth. As expected, 4.6 V Li||LiCoO2 batteries with superior EEIs can deliver excellent electrochemical performance.

Interfacial Modulation of a Self-Sacrificial Synthesized SnO2@Sn Core–Shell Heterostructure Anode toward High-Capacity Reversible Li+ Storage

“…Both species demonstrate the reduction of the high reactivity of TFSI – on the Sn electrode surface with respect to the growth SEI layer. Meanwhile, different from the N 1s spectrum in initial SOWSH@PCNC nanocomposites, the cycled electrode mainly proves the existence of the N–Sn bond derived from N doping at the heterojunction interfaces and Li 3 N species , that most likely relate to nitrogen-related matter reduced from the active TFSI – (Figure F). Overall, the atomic percentages of N and F contribute to 3.1 and 13.94 at.…”

Protecting Li-metal in O2 atmosphere by a sacrificial polymer additive in Li–O2 batteries

“…Chemically, amide groups can decompose into small molecules in an electrochemical environment under certain conditions. 18 Given that PAMMA contains abundant -CONH 2 groups and tends to break bonds preferentially than the solvent/salt in the electrolyte (Fig. 1c and Fig.…”

Fluorinated carbon nitride with a hierarchical porous structure ameliorating PEO for high-voltage, high-rate solid lithium metal batteries

“…20 The integration of LiF and Li 3 N to construct a Li 3 N-rich and LiF-rich composite SEI would considerably inhibit the formation of lithium dendrites. [20][21][22][23][24][25] For example, Li 3 PS 4 electrolyte coated with a Li 3 N-LiF composite layer shows a signicant suppression effect on Li dendrites; 20 a Li 3 N-LiF interface layer formed in PEO/LiTFSI which is ameliorated by mesoporous La x CoO 3 − d nanobers allows for stable cycling even when it was matched with a LiNi 0.8 Mn 0.1 Co 0.1 O 2 cathode. 25 However, the preparation processes above need either strict fabrication conditions or using expensive rare earth elements, and thus they are unsuitable for large-scale commercial manufacturing.…”