Fig. 1

Schematic diagram of the CSTR in preparing the ternary cathode materials with concentration-gradient hydroxide precusor[23]. Reprinted with permission, Copyright 2011 The Royal Society of Chemistry.

Fig. 2

(A) Schematic diagram of the core-shell concentration gradient material[25]. Reprinted with permission, Copyright 2009 Nature Publishing Group. (B) Schematic diagram of full concentration gradient material[26]. Reprinted with permission, Copyright 2012 Nature Publishing Group.

Fig. 3

EPMA line scan data of (A) precursor hydroxide Ni0.64Co0.18Mn0.18(OH)2 and (B) the final lithiated oxide Li(Ni0.64Co0.18Mn0.18)O2[25]. Reprinted with permission, Copyright 2009 Nature Publishing Group.

Tab. 1

Core-shell concentration gradient materials with different gradient designs

Fig. 4

(A) EPMA line scan data for the single-sloped full concentration gradient materials[26]. Reprinted with permission, Copyright 2012 Nature Publishing Group. (B) EPMA line scan data for the two-sloped full concentration gradient materials[52]. Reprinted with permission, Copyright 2015 Wiley-VCH.

Tab. 2

Comparison of properties of full concentration gradient materials with different nickel contents

Fig. 5

(A) EPMA composition profile of a single FCG61 cathode particle, (B) quantitative (at%) TEM EDS elemental mapping images of Ni, Co, and Mn for an Al-FCG61 particle, (C) TEM compositional line scan along a primary particle in Al-FCG61, and (D) bright field TEM image of an Al-FCG61 primary particle with its corresponding electron diffraction pattern[53]. Reprinted with permission, Copyright 2016 Wiley-VCH.

Fig. 6

Specific capacity vs. cycling stability plot of various layered cathodes, including gradient type NCMs and conventional NCAs and NCMs. The figure on the right graphically displays thermal stability measured using DSC of the different layered cathodes[55]. Reprinted with permission, Copyright 2017 American Chemical Society.

Fig. 7

Cross-sectional SEM images of (A, B) NCA82 and (C, D) TSFCG85 electrodes aged for 0 and 2 days at 55 °C after being charged to 4.3 V. High-magnification cross-sectional SEM images of the aged (E-G) NCA82 and (H-J) TSFCG85 cathodes aged for (H) 0, (I) 1, and (J) 3 days at 55 °C after being charged to 4.3 V[55]. Reprinted with permission , Copyright 2016 WILEY-VCH.

Fig. 8

(A) TEM image of the cycled TSFCG cathode in a pouch-type full cell for 1500 cycles, (B) electron diffraction pattern from a primary particle from the cycled TSFCG cathode in -120 zone of the layered structure. (C) TEM image of the cycled conventional cathode in a pouch-type full cell for 1500 cycles, (D) Broken-off primary particles from the cycled conventional cathode, and (E) electron diffraction pattern from the circled area in (B), indexed to 110 zone of the spinel phase[52]. Reprinted with permission, Copyright 2015 WILEY-VCH.