Fig 1

(a) Structure diagram of continuous stirred tank reactor. (b) Morphology of primary and secondary particles of hydroxide precursor."

Fig 2

Schematic diagram of (a) homogeneous and (b) heterogeneous nucleation. (c) The variation curve of total free energy (Gho) for homogeneous nucleation system with the radius (r) of embryo (nucleus) 34. (d) The variation curve of solute concentration (c) with time (t) during nucleation 36. (e) Solution state diagram during nucleation 37. (c) Adapted from Ref. 34. (d) Adapted from Ref. 36. Copyright © 1950, American Chemical Society. (e) Adapted from Ref. 37. Copyright © 2002 Elsevier Science B.V."

Fig 3

(a) Schematic illustration of the NH4+ passivated (001) crystal plane forming hexagonal nanosheet primary particles 39. (b) X-ray diffraction patterns of hydroxide precursors with different reaction times 39. (c) TEM morphology image of Ni1/3Co1/3Mn1/3(OH)2 collected at 1 h 39. (d) HRTEM image of the lateral view and the corresponding fast Fourier transform (FFT) pattern (inset) of nanosheets in (c) 39. (e) HRTEM image of the frontal view and the corresponding FFT pattern (inset) of nanosheets in (c) 39. (f) The calculated surface energies of different surface orientations by DFT 40. (g) Schematic diagram of the growth process for rod or needle primary particles 40. (a–e) Adapted from Ref. 39. Copyright © 2017 Elsevier Ltd. (f–g) Adapted from Ref. 40. Copyright © 2014 Elsevier B.V."

Fig 4

(a) Primary particles agglomeration process 40. (b) Primary particles sharp edge smoothing process 40. (c) Primary particles agglomeration and sharp edge smoothing process, accompanied by the re-crystallization of the particles in the cross gap 40. SEM images of Ni1/3Co1/3Mn1/3(OH)2 as a function of reaction time for (d–i) 1, 3, 8 h, 14, 24 and 29 h 39. (a–c) Adapted from Ref. 40. Copyright © 2014 Elsevier B.V. (d–i) Adapted from Ref. 39. Copyright © 2017 Elsevier Ltd."

Fig 5

The variation curves of molar concentration for species containing (a) Ni, (b) Co and (c) Mn with pH in Ni-Co-Mn-NH3-H2O system 42. (d) The variation curves between Gibbs free energy of metal hydroxides in solution and pH 39. (e) The variation curves between the molar concentration of metal complexing compounds in solution and pH 43. SEM images of Ni0.6Co0.2Mn0.2(OH)2 precursors prepared at the ammonia concentration of 0.5 mol·L−1 and pH value of (f) 11.0, (g) 11.4 and (h) 11.6, respectively 19. (i) The relationship between the pH value and ammonia concentration of Ni1−x−yCoxMny(OH)2 with different compositions 45. SEM images of Ni0.8Co0.1Mn0.1(OH)2 precursors prepared at the pH value of 11.5 and ammonia concentration of (j) 1.0 mol·L−1, (k) 1.3 mol·L−1 and (l) 1.4 mol·L−1, respectively, the inserts were corresponding low magnification image 42. (a–c) Adapted from Ref. 42. (d) Adapted from Ref. 39. Copyright © 2017 Elsevier Ltd. (e) Adapted from Ref. 43. Copyright © 2009, American Chemical Society. (f–h) Adapted from Ref. 19. Copyright © 2021, American Chemical Society. (i) Adapted from Ref. 45. (j–l) Adapted from Ref. 42."

Fig 6

SEM images of Ni0.8Co0.1Mn0.1(OH)2 precursors prepared with salt solution concentration of 2 mol·L−1, salt solution feed rate of (a) 0.2 mL·min−1, (b) 0.5 mL·min−1 and (c) 2.5 mL·min−1, and (d) salt solution concentration of 3 mol·L−1, salt solution feed rate of 0.5 mL·min−1 42. (e) The relationship of precursor particle size and tap density with time during the process of removing the supernatant and adjusting the pH value 49. SEM images of Ni0.65Co0.15Mn0.20(OH)2 precursors prepared at (f) 10 h, (g) 23 h and (h) 66 h in the process shown in (e), with (i) cross-section image at 66 h 49. (a–d) Adapted from Ref. 42. (e–i) Adapted from Ref. 49."

Fig 7

SEM images of Ni0.50Co0.20Mn0.30(OH)2 precursors prepared at (a, d) 12 h, (b, e) 30 h and (c, f) 60 h 50. SEM images of Ni0.8Co0.1Mn0.1(OH)2 precursors prepared at (g) 43 ℃, (h) 48 ℃, (i) 53 ℃ and (j) 58 ℃, respectively 51. SEM images of Ni0.8Co0.1Mn0.1(OH)2 precursors were obtained after 100 min when the ratio of base solution volume to tank reactor volume was (k) 0.7 and (l) 0.35 52. SEM images of Ni0.8Co0.1Mn0.1(OH)2 precursors were obtained after 720 min when the ratio of base solution volume to tank reactor volume was (m) 0.7 and (n) 0.35 52. (a–f) Adapted from Ref. 50. (g–j) Adapted from Ref. 51. (k–n) Adapted from Ref. 52."

Fig 8

SEM images of Ni0.6Co0.2Mn0.2(OH)2 precursor obtained at stirring rate of (a) 400 r∙min−1, (b) 600 r∙min−1 and (c) 800 r∙min−1, respectively 53. The circulating flow path of liquid in the tank reactor (d) before and (e) after installing the guide cylinder and baffle. Flow patterns generated by (f) paddle agitator, (g) propeller agitator, (h) turbine agitator and (i) anchor and gate type agitator when baffle is installed. (j) X-ray diffraction patterns of Ni0.8Co0.1Mn0.1(OH)2 precursor obtained at different aging and placing times 42. (k) SEM images of Ni0.8Co0.1Mn0.1(OH)2 precursor obtained at aging time of 12 h and 24 h 42. (l) X-ray diffraction patterns of precursor obtained by different drying processes 55. (a–c) Adapted from Ref. 53. Copyright © 2014 Elsevier Ltd. (j–k) Adapted from Ref. 42. (l) Adapted from Ref. 55."