Practical Implementation of Magnetite-Based Conversion-Type Negative Electrodes via Electrochemical Prelithiation

Abstract

We report the performance of a conversion-type magnetite-decorated partially reduced graphene oxide (Fe3O4@PrGO) negative electrode material in full-cell configuration with LiNi0.8Co0.15Al0.05O2 (NCA) positive electrodes. To enable practical implementation of the conversion-type negative electrodes in full cells, the beneficial impact of electrochemical prelithiation on mitigating active lithium losses and improving cycle life is shown here for the first time in the literature. The initial Coulombic efficiency (ICE) of the full cells is improved from 70.8 to 91.2% by prelithiation of the negative electrode to 35% of its specific delithiation capacity. The prelithiation is shown to improve the surface passivation of the Fe3O4@PrGO electrodes, leading to less electrolyte reduction on their surface which is prominent from the significantly lowered accumulated Coulombic inefficiency values, lower polarization growth, and doubled capacity retention by the 100th cycle. The reduced surface reactions of the negative electrode by prelithiation also aids in reducing the extent of aging of the NCA positive electrode. Overall, the prelithiation leads to a longer cycle life, where a retained capacity of 60.4% was achieved for the prelithiated cells by the end of long-term cycling, which is 3 times higher than the capacity retention of the non-prelithiated cells. Results reported herein indicate for the first time that the electrochemical prelithiation of the Fe3O4@PrGO electrode is a promising approach for making conversion negative electrode materials more applicable in lithium-ion batteries.

Li2Cu0.1Ni0.9O2 with Copper Substitution: A New Cathode Prelithiation Additive for Lithium-Ion Batteries

“…In addition, the cycling performance with LCNO additive in the full cell is more stable than that of the pristine (Figure d). It may attribute to the formation of stable cathode electrolyte interphases on the surface of NCM811 brought by cathode prelithiation additive activation. , Besides, recent studies proved that prelithiation could enhance the structural stability of SEI from anodes with slight volume changes. , Figure S14 shows the electrochemical properties of graphite/NCM811 full-cells with different contents of LCNO additives. The cell with 20% additive reveals a remarkable charge capacity for the initial cycle, but the discharge capacity is severely deteriorated (Figure S14a).…”

“…42,48 Besides, recent studies proved that prelithiation could enhance the structural stability of SEI from anodes with slight volume changes. 49,50 Figure S14 shows the electrochemical properties of graphite/NCM811 full-cells with different contents of LCNO additives. The cell with 20% additive reveals a remarkable charge capacity for the initial cycle, but the discharge capacity is severely deteriorated (Figure S14a).…”

Lithium sulfide: a promising prelithiation agent for high‐performance lithium‐ion batteries

“…Electrochemical prelithiation can be simply expressed as the first discharge process of anode materials in the half cell (Figure 2B). During electrochemical prelithiation, SEI is formed on the anode material surface by consuming Li + resource from Li metal 67–71 . Compared with uncontrollable mechanical prelithiation, short‐circuiting risk is eliminated.…”

“…During electrochemical prelithiation, SEI is formed on the anode material surface by consuming Li + resource from Li metal. [67][68][69][70][71] Compared with uncontrollable mechanical prelithiation, short-circuiting risk is eliminated. Moreover, the prelithiation rate and prelithiation degree can be controlled precisely in a mild way by adjusting the electrochemical prelithiation parameter.…”

Morphology-Dependent Investigation of Li-ion Insertion into Single Crystal Hematite α-Fe2O3 Nanostructures

“…Increasing the gravimetric and volumetric energy densities of Li-ion batteries with more economic and abundant materials is crucial for the widespread usage of sustainable energy. Abundant, environmentally friendly, and low-priced metal oxides such as Fe 2 O 3 , Fe 3 O 4 , MnO, CuO, and TiO 2 possess Li-ion storage abilities with higher theoretical specific capacities and power densities than graphite. − Their utilization is hindered by their low Coulombic efficiencies and large potential hysteresis due to the complex mechanisms of the Li-ion storage. , Among the various metal oxides, hematite iron oxide (α-Fe 2 O 3 ) is abundant, cheap, easy to prepare, and has a very high theoretical specific capacity for Li-ion storage (≈1006 mAhg –1 ) . It has great potential to be applied as an anode material for not only Li-ion storage but also Na-ion and K-ion storage applications. , …”