Aluminum Impurity from Current Collectors Reactivates Degraded NCM Cathode Materials toward Superior Electrochemical Performance

Abstract

The huge amount of degraded NCM (LiNi0.5Co0.2Mn0.3O2) cathode materials from spent lithium-ion batteries is arising as a serious environmental issue as well as a severe waste of metal resources, and therefore, direct recycling of them toward usable electrode materials again is environmentally and economically more attractive in contrast to present metallurgical treatments. In this work, we design a robust two-step method for direct recycling of degraded NCM materials, which uses the aluminum impurity from the attached current collector to supplement the transition metal vacancies for simultaneous elemental compensation and structural restoration. This single-element compensation strategy leads to the regeneration of high-quality NCM material with depressed cation disordering and stabilized layered structure. Moreover, the regenerated NCM material with controllable Al doping delivered an outstanding electrochemical performance; specifically, the capacity (158.6 mAh g–1), rate capability (91.6 mAh g–1 at 5 C), and cycling stability (89.6% capacity retention after 200 cycles) of the regenerated NCM material are even comparable with those of fresh materials. The as-established regeneration protocol has its chance in simplifying the industrial recycling process of degraded NCM materials.

Organic Eutectic Salts‐Assisted Direct Lithium Regeneration for Extremely Low State of Health Ni‐Rich Cathodes

“…All three materials exhibit the typical hexagonal structure of the R‐3m symmetric space group. [ 20 ] Analyzing the (003), (108), and (110) crystal planes, it is evident that the (003) peak of Low SOH NCM shifts to a lower angle compared to commercial NCM (C‐NCM) in Figure 2b. This indicates that Low SOH NCM expands along the c ‐axis direction, increasing the layer spacing of the layered structure.…”

Engineering Phase to Reinforce Dielectric Polarization in Nickel Sulfide Heterostructure for Electromagnetic Wave Absorption

“…[30] The EPR signal of NiS 2 /NiS is stronger than that of NiS 2 , proving the presence of intense V S . NiS is more S2 (Supporting Information): [7] NiS/MoS 2 /Ti 3 C 2 T x , [8] graphene-NiS 2 /Ni 3 S 4 , [9] n-Ni x S y @NSC-800, [10] NiS 2 @MoS 2 , [11] NiS 2 /SnS 2 , [12] NiS 2 , [13] NiS/Ni 3 S 4 @PPy@MoS 2 , [14] NiS/Ni 3 S 4 , [15] RGO-NiS 2 /NiS, [16] Fe-NiS 2 /NiS/PVDF, [17] CoS/MnSO 4 , [18] Co-CoS 2 @C, and [19] Cu 9 S 5 /C-3 (Supporting Information). RCS for d) PEC, e) NiS 2 , f) NiS 2 /NiS, and g) NiS.…”

“…Therefore, achieving the precise controllability of phases transition and maintaining the pristine morphology to understand the loss mechanism and guide the development of highly efficient EM absorbers is urgent but remains challenging. [15] In this work, a seed phase decomposition-controlled strategy is developed to achieve phase transition controllable in nickel sulfides (NiS x ) with a hollow sphere structure. Experimental characterizations and theoretical studies confirm that the NiS 2 -NiS 2 /NiS-NiS phase transition derivates the generation of abundant heterogeneous interfaces and defects (lattice defects and sulfur vacancies), around which triggered interface interaction and charge redistribution are of great benefits to the dielectric response.…”

Fundamentals, status and challenges of direct recycling technologies for lithium ion batteries

“…In the direct recycling of NCM and NCA, upcycling can be achieved by combining other conventional modification methods such as doping and coating. [176][177][178] However, for highly commercial materials such as ternary cathodes, market demand will guide their upgrade direction, and researchers must follow this. For NCM, to meet the market's requirements for cathode materials in relation to energy density, service life, and safety performance, improvements in nickel content, single-crystallization, and high voltage behavior are already recognized development directions, 179,180 and these have naturally become the research direction of spent NCM upcycling.…”