Rejuvenating Propylene Carbonate‐based Electrolyte Through Nonsolvating Interactions for Wide‐Temperature Li‐ions Batteries

Abstract

The advancements of lithium‐ion batteries indubitably call for advanced electrolytes with superior environmental adaptability and long‐term stability. Propylene carbonate (PC) proves to be a competitive solvent with the high permittivity and wide‐liquid range, while the application is intrinsically hindered by the poor graphite compatibility and high viscosity. Here, a PC‐based electrolyte with wide‐temperature range is developed by tuning the strength and topology of the Li+‐PC interactions via non‐solvating interactions without altering the solvation structure. Thus, the problem of graphite exfoliation caused by Li+‐PC co‐intercalation can be successfully mitigated. Consequently, such electrolyte shows compatibility with both graphite and high‐nickel cathode, exhibiting an expanded liquid range from −90 to 90 °C. This work, breaking from the traditional EC‐based formula, provides a new strategy for designing PC‐enabled electrolyte featuring high performance, wide‐temperature compatibility, and sustainability

Dipole–dipole interactions for inhibiting solvent co-intercalation into a graphite anode to extend the horizon of electrolyte design

“…, DEC), participate competitively in the solvation structure, resulting in significantly altered Li + coordination. In contrast, the non-coordinating co-solvents (non-solvents), keeping inert to Li + but separating the bulk solvation network to individual solvent-ion clusters since the subtle non-solvent-solvent interactions, 24–27 provide another avenue to tune the strength and topology of Li + -solvents. Furthermore, a desirable non-solvent can ameliorate physical properties ( e.g.…”

“…22,23 Note that these solvating components, no matter the strong coordinator (e.g., LiNO 3 and EC) or low CN solvents (e.g., DEC), participate competitively in the solvation structure, resulting in significantly altered Li + coordination. In contrast, the non-coordinating co-solvents (non-solvents), keeping inert to Li + but separating the bulk solvation network to individual solvent-ion clusters since the subtle non-solventsolvent interactions, [24][25][26][27] provide another avenue to tune the strength and topology of Li + -solvents. Furthermore, a desirable non-solvent can ameliorate physical properties (e.g., viscosity, eutectic solvent and wettability) and inspire a new dimension for electrolyte design.…”

Electrolyte Optimization for Graphite Anodes toward Fast Charging

“…Note that HCEs are the foundation of LHCE functionality; therefore, the purpose of diluting an HCE is to reduce the overall salt concentration in the LHCE but retain the highly concentrated salt-solvent clusters as they are in the HCE. Many efforts have been made to develop LHCEs, leading to a flourishing research field of low-temperature LIBs (working under −20 °C and below). − …”

Polymer Competitive Solvation Reduced Propylene Carbonate Cointercalation in a Graphitic Anode

“…24 Moreover, the PC cointercalation and the structural damage of graphite lead to increased bulk resistance (R bulk ) and charge transfer resistance (R ct ). 11,25 The reduction peaks at 1.1 and 0.65 V in the first discharge (Figure 2a) arise from the in-advance reduction of the TFSI − anion 26 and the reduction of polymer/solvent, 27,28 respectively. These two peaks disappear in the second cycle, and the (dis)charge CV profiles overlap with each other thereafter, implying the formation of a stable electrode/ electrolyte interphase.…”