One-Dimensional Oxide Nanostructures Possessing Reactive Surface Defects Enabled a Lithium-Rich Region and High-Voltage Stability for All-Solid-State Composite Electrolytes

Abstract

The development of highly safe and low-cost solid polymer electrolytes for all-solid-state lithium batteries (ASSLBs) has been hindered by low ionic conductivity, poor stability under high-voltage conditions, and severe lithium-dendrite-induced short circuits. In this study, Li-doped MgO nanofibers bearing reactive surface defects of scaled-up production are introduced to the poly­(ethylene oxide) (PEO)/lithium bis(trifluoromethanesulfonyl)­imide (LiTFSI) system. The characterizations and density functional theory calculations reveal that TFSI– is strongly adsorbed on the nanofibers based on the electrostatic interactions of surface oxygen vacancies and the formation of Li–N and Li–O bonds derived from the exposed Li. Additionally, the introduced Li exposed near oxygen vacancies may be liberated from the lattice and engage in the formation of Li-rich domains. Therefore, a high ionic conductivity of 1.48 × 10–4 S cm–1 for the solid electrolyte at 30 °C and excellent cycling stability for the assembled battery, with a discharge capacity retention of 85.2% after 1500 cycles at 2C, can be achieved. Furthermore, the increased coordination of EO chains in the Li-rich region and chemical interactions with nanofibers substantially improve the antioxidant stability of the solid electrolyte, endowing the LiNi0.8Co0.1Mn0.1O2/Li battery with a long lifespan of more than 700 cycles. The results of this study suggest that the surface defects of 1D oxide nanostructures can substantially improve the Li+ diffusion kinetics. This study provides insight into the construction of Li-rich regions for high-voltage ASSLBs.

Uniform Boron Nitride Nanospheres with Reactive Surface Defects for Composite Solid-State Electrolytes

“…This is related to the grafting reaction of –OH and −NH 2 during the ammonia fixation treatment. The O 1s binding energy spectrum could be decomposed into two peaks (Figure h), attributed to oxygen-deficient species (532.2 eV) and adsorbed surface oxygen (533.9 eV), referred to as O I and O II regions, , respectively. This is due to complex oxygen vacancies, resulting from the removal of some oxygen impurities by high-temperature ammonia fixation.…”

“…Solid electrolyte was widely regarded as the best electrolyte because it could solve the issues of leakage, flammability, and limited flexibility encountered in traditional liquid lithium-ion batteries, significantly improving battery safety and energy density. , The solid polymer electrolyte (SPE) was anticipated to play a pivotal role in the next wave of advanced energy storage technologies owing to their high shear modulus and exceptional interfacial compatibility. − However, challenges such as low ion conductivity (10 –8 to 10 –7 S cm –1 ) at ambient temperature, poor lithium stability, and low oxidation potential severely limit its further application. − Although introducing ionic liquids and plasticizers to create gel polymer electrolytes can enhance ionic conductivity, this approach mirrors the working principle of liquid electrolytes and substantially compromises mechanical strength. − …”

Design of Ultrathin Asymmetric Composite Electrolytes for Interfacial Stable Solid-State Lithium-Metal Batteries

“…This improvement can be attributed to the presence of additional transport pathways created by LLZO nanofibers. 38 In addition, long-term cycling stability tests of all-SSLMBs were conducted at 1.0 C (Figure 4b). The LFP/ACE/Li cell could provide a specific capacity of 139.5 mAh g −1 after 600 cycles, corresponding to a capacity retention of 90.6%, which was much higher than that of the LFP/PLP/Li cell (capacity retention of 44.9%).…”

“…The LFP/ACE/Li cell displayed a reduced polarization potential, as evidenced by the charge/discharge curves (Figure S26), indicating the faster Li + transport kinetics in ACE. This improvement can be attributed to the presence of additional transport pathways created by LLZO nanofibers . In addition, long-term cycling stability tests of all-SSLMBs were conducted at 1.0 C (Figure b).…”

Revealing the Influence of Electron Migration Inside Polymer Electrolyte on Li+ Transport and Interphase Reconfiguration for Li Metal Batteries

“…As a response to tackling the insufficient Li + throughput, structural design on 1D nanofillers provides feasible solution for the breakthrough of Li-ion conductivity. [5] In comparison with the extensively-studied Li + -conductive nanofillers such as Li 7 La 3 Zr 2 O 12 , [6] Li 1 +…”