Determination of lithium and transition metals in Li₁Ni_1/3Co_1/3Mn_1/3O₂ (NCM) cathode material for lithium‐ion batteries by capillary electrophoresis

Abstract

In this work, we present a novel electrophoretic method that was developed for the determination of lithium and transition metals in LiNi Co Mn O cathode material after microwave digestion. The cations in the digested LiNi Co Mn O material were separated by CE and the element content was determined by UV/Vis detection. To characterize the precision of the measurements, the RSDs and concentrations were calculated and compared to those obtained with ICP-optical emission spectrometry (ICP-OES). Furthermore, a certified reference material (BCR 176R-fly ash) was investigated for all techniques. For active material components, the LOD and LOQ were determined. The LODs and LOQs for the metals determined by CE were as follows: lithium (LOD/LOQ): 17.41/62.70 μg/L, cobalt (LOD/LOQ): 348.4/1283 μg/L, manganese (LOD/LOQ): 540.2/2095 μg/L, and nickel (LOD/LOQ): 838.0/2982 μg/L. Recovery rates for lithium were in the range of 95-103%. It could be proven that with the new technique, the results for the determination of the lithium content of active material were comparable with those obtained by ICP-OES and ion chromatography. Furthermore, the recovery rates of the transition metals were determined to be between 96 and 110% by CE and ICP-OES.

Chromatographic Techniques in the Research Area of Lithium Ion Batteries: Current State-of-the-Art

“…For analysis of cations in the LIB research context, Vortmann-Westhoven et al showed a capillary electrophoresis (CE) separation method with UV/vis detection for the determination of lithium and transition metals after microwave digestion [135]. They compared this developed method to results obtained with IC and inductively coupled plasma-optical emission spectroscopy (ICP-OES) and could get comparable results in terms of recovery rates and general analytical figures of merit.…”

Exploiting the Degradation Mechanism of NCM523Graphite Lithium‐Ion Full Cells Operated at High Voltage

“…demonstrated that the choice of anode material can significantly influence the capacity retention and cycle life [39] . In case of Li metal [40] or graphite anodes, [41] operating at low potentials vs. Li|Li + , the deposited Mn II showed a strong impact on performance, whereas Li 4 Ti 5 O 12 , having a high operation potential, only showed a negligible effect on performance by Mn II deposition [39] . Additionally, Gilbert et al.…”

“…[31] In regard of Mn II deposition at the anode surface, Zhan et al demonstrated that the choice of anode material can significantly influence the capacity retention and cycle life. [39] In case of Li metal [40] or graphite anodes, [41] operating at low potentials vs. Li j Li + , the deposited Mn II showed a strong impact on performance, whereas Li 4 Ti 5 O 12 , having a high operation potential, only showed a negligible effect on performance by Mn II deposition. [39] Additionally, Gilbert et al showed that the majority of capacity loss in highvoltage LIB cells can be contributed to irreversible lithium loss in the SEI at the anode, induced by TM deposition.…”

Deciphering the lithium ion movement in lithium ion batteries: determination of the isotopic abundances of 6Li and 7Li

“…14,23,[27][28][29] Although there is a sophisticated repertoire of electrochemical methods for monitoring, the need for additional analytical methods is indispensable. [30][31][32][33][34] For direct solid analysis, methods like glow discharge-mass spectrometry (GD-MS), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), time of ight-secondary ion mass spectrometry (TOF-SIMS) and X-ray photoelectron spectroscopy (XPS). [35][36][37][38][39][40][41][42] Due to their capabilities of directly measuring the surface components, they represent promising approaches for analyzing new materials as well as the degradation of aged cells.…”