Tailoring electrolyte enables high-voltage Ni-rich NCM cathode against aggressive cathode chemistries for Li-ion batteries

The genesis and control of microcracks in nickel-rich cathode materials for lithium-ion batteries

“…Accordingly, different functional additives of electrolyte are in high demand for the construction of a stable cathode-electrolyte interface. [96][97][98][99] For example, Cheng et al 100 found that the addition of lithium diuoro(oxalato)borate and tris(trimethylsilyl)phosphate into the carbonate electrolyte contributed enormously to the microcrack suppression. During cycling, these two additives would undergo oxidization and decomposition to form stable F, B, and Si-rich cathode-electrolyte interface (CEI) layers, whose existence could act as effective protective layers to diminish the continuous decomposition of the electrolyte and the dissolution of transition metal ions.…”

Borate-Functionalized Disiloxane as Effective Electrolyte Additive for 4.5 V LiNi0.8Co0.1Mn0.1O2/Graphite Batteries

“…Yang et al reported the synergistic effect of 3-(trifluoromethyl)benzoylacetonitrile and lithium difluoro(oxalato)borate (LiD-FOB) as electrolyte additives to improve the cycle life and safety performance of battery at 4.4 V. 16 Park et al found that diphenyl diselenide as a bifunctional electrolyte additive could stabilize the cathode/anode interface by formation CEI/SEI protective layers for NCM811/graphite cells at 4.5 V. 17 Pham et al improved the cycling performance of NCM811/graphite cells at 4.5 V by using fluorinated linear carbonates as electrolyte solvents to stabilize the layer structure of NCM811 cathode and form CEI film. 18 Very recently, tris-(trimethylsilyl)-phosphate with LiDFOB was reported as a dual film-forming additive to build an F, B, and Si-rich CEI film on the surface of the NCM811 cathode, which dramatically inhibited the decomposition of the electrolyte, the dissolution of transition metal, the transition of surface phase and the gasgeneration, thus improved cycling performance even at 4.7 V. 19 It is well-known that the inevitable acidic species generated from the hydrolysis of LiPF 6 in the electrolyte can accelerate the structural damage and transition metal ion dissolution of the NCM811 cathode material and then deteriorate the cycling life of the cells. So far, few such additives combining filmforming and acid-scavenging functions in one identical molecule have been reported for NCM811 batteries at high operating voltage.…”

Tuning Dopant Distribution for Stabilizing the Surface of High‐Nickel Layered Oxide Cathodes for Lithium‐Ion Batteries

“…Numerous strategies have been explored to enhance the stability of high-Ni cathodes, encompassing elemental doping, surface coating, and optimization of electrolyte formulations. [11,[22][23][24][25][26][27][28][29][30][31][32][33][34][35][36] Various doping elements, such as Co, Mn, Mg, Al, Ti, and Zn, have been investigated. [30,[37][38][39][40][41][42][43][44][45] Among them, Al doping stands out as it can effectively enhance the chemical stability, suppress particle pulverization, and mitigate TM dissolution.…”