Electrochemical analysis of electrolyte additive effect on ionic diffusion for high-performance lithium ion battery

Abstract

Lithium ion batteries have gained increasing attention in the last two decades. Perfoming electrolyte additive into lithium ion battery could enhance the baterry performance. However several studies on electrolyte additive only show the experimental data. The behavior of battery kinetic inside the battery and the ionic diffusion during operation was not analyzed. This study will investigate the effect of electrolyte additive on ionic diffusion of battery based on electrochemical model. The role of the electrolyte is to provide an ionic conduction path between the anode and the cathode. This study elucidates the improvement of the cycleability by performing the electrolyte containing 0.1 wt % of Flouro-ophenylenedimaleimide (F-MI) based additive compared to the electrolyte with 0.1 wt % N,N'-o-phenylenedimaleimide (O-MI) and without an additive shown by effective constant phase elements (CPE) coefficient of impedance spectra on electrochemical impedance spectroscopy (EIS). The result elucidates that many amount of lithium ion remains on SEI layer of the mesocarbon microbeads (MCMB) half cell with F-MI additive, indicating that ion move easily because of high diffusion. The simulation result elucidated the agreement with the experimental data, the diffusion of the MCMB half-cell with F-MI additive is highest compared to MCMB half-cell with O-MI and without additive, that is emphasized with result on the EIS test.

Face to Face at the Cathode Electrolyte Interphase: From Interface Features to Interphase Formation and Dynamics

“…[131][132][133][134][135][136][137] In case of high voltage application, the substitution of hydrogen with fluorine atoms leads to reduced activation energy [138] and decreased HOMO and LUMO energy levels, thus resulting in increased reduction and decreased oxidation potentials. [12,95,133,[139][140][141] In most cases, this decreased HOMO energy level leads to improved cycling performance which is related to the early formation of an effective CEI layer as well as to the decreased overall impedance. [95,133,139,142] There are numerous publications in the recent years featuring fluorinated high voltage additives.…”

Fluorine and Lithium: Ideal Partners for High‐Performance Rechargeable Battery Electrolytes

“…However, fluorination leads to an improved cycling performance, because of the lower R CT value, but the position of the fluorination (at both alkyl chains or only at one alkyl chain) has no impact on the cycling performance or on the impedance . The same effect on the impedance decrease for the R SEI as well as R CT values was observed when hydrogen was substituted by fluorine in maleimide‐based additives . This class of additives suffers from severe capacity fading, as their reduction occurs at low potentials and then interferes with the intercalation chemistry.…”

“…The substitution of hydrogen by fluorine atoms leads to reduced activation energy and decreased HOMO and LUMO energy levels, thus resulting in increased reduction and increased oxidation potentials . An increased reduction potential can lead to the formation of an effective SEI, which suppresses further electrolyte decomposition and leads to an improved cycling behavior at constant current …”

The understanding of solid electrolyte interface (SEI) formation and mechanism as the effect of flouro‐o‐phenylenedimaleimaide (F‐MI) additive on lithium‐ion battery

“…The grade of the SEI layer can be significantly improved by applying a small amount of electrolyte additive. Electrolyte additive can suppress the decomposition of carbonate solvent, which causes exfoliation on the anode surface . It has been proven that maleimide‐based additive can improve the capability and cycle ability due to its low Lowest Unoccupied Molecular Orbital (LUMO) energy and high reductive potential compared with alkyl carbonates, such as EC, PC, and Diethyl Carbonate (DEC) .…”

“…Electrolyte additive can suppress the decomposition of carbonate solvent, which causes exfoliation on the anode surface. 6 It has been proven that maleimide-based additive can improve the capability and cycle ability due to its low Lowest Unoccupied Molecular Orbital (LUMO) energy and high reductive potential compared with alkyl carbonates, such as EC, PC, and Diethyl Carbonate (DEC). 7 Study reports that maleimide has phenyl group in the middle of the structure, which conjugate the π orbital and the resonance structure of the phenyl group; hence, MI-based additives have higher reduction potential, inhibiting a competitive reaction between MI and the alkyl carbonates; this phenomenon reduces the irreversibility state and increases reversibility of electrochemical reaction and current density.…”