Reversible chemical delithiation/lithiation of LiFePO₄: towards a redox flow lithium-ion battery

Abstract

Reversible chemical delithiation/lithiation of LiFePO(4) was successfully demonstrated using ferrocene derivatives, based on which a novel energy storage system--the redox flow lithium-ion battery (RFLB), was devised by integrating the operation flexibility of a redox flow battery and high energy density of a lithium-ion battery. Distinct from the recent semi-solid lithium rechargeable flow battery, the energy storage materials of RFLB stored in separate energy tanks remain stationary upon operation, giving us a fresh perspective on building large-scale energy storage systems with higher energy density and improved safety.

A chemistry and material perspective on lithium redox flow batteries towards high-density electrical energy storage

“…123 Wang and co-workers demonstrated a semi-solid Li-redox flow cell using LiFePO 4 nanoparticles as the Li + -storage material, and binary ferrocene and its derivative as the mediator for redox targeting of the LiFePO 4 nanoparticles. 124 The general principle of the redox targeting method (Fig. 14a) is based on the chemical lithiation/delithiation of electro-active materials with poor electronic conductivity, which allows fast charge transport thus may enhance the power density of the cell.…”

Techno-Economic Modeling and Analysis of Redox Flow Battery Systems

“…This means that, for example, lithium ion RFBs must achieve discharge power densities of at least 30 mW/cm 2 for the system costs to be the same as for a VRFB. Some current lithium ion RFBs are several orders of magnitude below this value [25][26][27][28]. The current densities of commercial lithium ion batteries lie within the single-digit mA range; they only have large electrode areas-and hence acceptable volumetric power densities-because of their comparatively extremely thin construction [29].…”

Redox Flow Batteries: Fundamentals and Applications

“…In contrast to the flow batteries with both (de)lithiation and electron transfer reactions occurring inside the electrochemical cells (Figure 2d), a new concept using redox shuttle molecules has been introduced [38], wherein solid active materials are kept statically in the tank and only the shuttle molecules are circulated in the electrochemical cell ( Figure 4). Electrochemical redox reactions of the shuttle molecules go on at the electrode inside the cell, whereas chemical (de)lithiation of the active solid materials in the tank occurs through the reactions between the solid materials and the shuttle molecules.…”