Electrochemical Relithiation for Direct Regeneration of LiCoO₂ Materials from Spent Lithium-Ion Battery Electrodes

Abstract

Increased generation of spent lithium-ion batteries (LIBs) has driven the exploration of new methods for reusing and/or recycling LiCoO2 cathode materials. Herein, an electrochemical relithiation method was proposed to directly regenerate LiCoO2 cathode materials using the waste Li x CoO2 electrode as a base. It was shown that Li+ was successfully inserted into the waste Li x CoO2 electrode, and this relithiation process became faster with either a higher Li2SO4 concentration or a higher cathodic current density. The XRD analysis confirmed that the peak positions of the relithiation products were consistently close to those of a standard LiCoO2 material. The crystal structure of the relithiation products was restored with a post-annealing process. The activation energy for electrochemical relithiation (E a) was estimated at 22 kJ mol–1, and the constant of equilibrium constant k 0 was determined as 1.35 × 10–6 cm s–1. The relithiation process was controlled by the charge transfer process when the Li2SO4 concentration was high (e.g., 1, 0.8, and 0.5M), and a lower concentration at 0.01–0.3 M led to a diffusion control pattern. The electrode made of the regenerated LiCoO2 materials had a charge capacity of 136 mAh g–1, close to that of the commercial LiCoO2 electrode (140 mAh g–1). A potential mechanism of electrochemical relithiation was proposed involving lithium defects, relithiation, and crystal regeneration.

Nano and Battery Anode: A Review

“…It has been shown that using silicon nanotubes instead of nanowires is more effective. In nanotubes, the necessary space is provided for volume change on both sides of the inner and outer walls [34,[59][60][61]. In addition, nanotubes are usually thinner than nanowires, so transmitters are better, because silicon is a semiconductor and is also amorphous during the duty cycle due to stresses, it does not conduct well electronically during the duty cycle [47,48,54].…”

“…Another way to solve the problem is hollow nanostructures. In this method, the necessary empty space is provided during the entry and exit of lithium through a hollow volume [26,27,33,58,59]. The finite element method shows that in the same volume, the hollow structure undergoes less stress during the work cycle, so they have better resistance to the crushing phenomenon (Fig.…”

“…This is also an advantage of LTO, as the preparation of TiO 2 nanostructures is very popular. Due to the problem of low volumetric density and agglomeration of nanomaterials, micron secondary particles made from nanoscale primary particles are more useful [ 33 , 38 , 58 , 59 ].…”

“…Due to the problem of low volumetric density and agglomeration of nanomaterials, micron Fig. 17 a Displays the nanostructure discussed including Nano primary nanoparticles, b charge-discharge curve for ordinary micro particles, and c for a-shaped particles [74] secondary particles made from nanoscale primary particles are more useful [33,38,58,59].…”

Reuse of LiCoO2 Electrodes Collected from Spent Li‐Ion Batteries after Electrochemical Re‐Lithiation of the Electrode

“…[4,[9][10][11][12][13][14][15] However, the processes are often complicated with several steps and utilize concen-published. [33][34][35] Zhang et al, [33] for example, have recently shown that the re-lithiation of Li x CoO 2 electrode is possible without removing the active material from the current collector foil. However, in all these studies, LiCoO 2 was at some point removed from the current collector.…”