List of Figures
xxiii
The MgO peaks were truncated at 500 cps and
∗ indicates their
positions. For ease of viewing, a polynomial background was fit
and subtracted from each scan. The vertical lines indicate peak
positions and relative intensities from the JCPDS database........
42
Fig. 3.7
a Peak areas as a function of temperature. Open symbols are for
the Li 2 CO 3 (002) peak. The closed triangles represent the large
stearate peak (divided by 30) obtained with ammonium
bicarbonate and heated in air. b Li x Ni 2−x O 2 crystallite size.
c Strain as a function of temperature. Error bars smaller than the
symbols were omitted ..................................................
44
Fig. 3.8
Lithium content measured by X-ray diffraction (XRD) versus the
amount dispensed .......................................................
44
Fig. 3.9
Calculated lithium content as a function of temperature. Closed
symbols indicate samples made by dispensing 20 μL of solution
as compared to 10 μL for the open symbols .........................
45
Fig. 4.1
The entire Gibbs triangles for samples heated to 800
◦ C in air and
quenched (a), or regular cooled (b). Sample A 4 is at the
composition Li 0.5 Mn 0.25 Co 0.25 and is referred to throughout the
text. Green dashed lines are tie-lines, solid red lines are
boundaries to single-phase regions while red dotted lines are
tie-lines bounding three-phase regions ...............................
50
Fig. 4.2
Stack of X-ray diffraction (XRD) patterns with fits and difference
plots obtained by heating to 800
◦ C and regular cooling. The
vertical lines indicate peaks from the JCPDS database, reference
#84-1634 for Li 2 MnO 3 and #74-1656 for Co 3 O 4 . The unlabeled
scans between A 4 and Li 2 MnO 3 are evenly spaced in composition
between the two end members. For clarity, only every third data
point is plotted...........................................................
51
Fig. 4.3
a Stack of X-ray diffraction (XRD) patterns for samples lying
between LiCoO 2 and point A 4 obtained by heating to 800
◦ C and
regular cooling. The red lines indicate the layered peaks while the
blue lines represent the positions of the Co 3 O 4 peaks. The
vertical lines for LiCoO 2 are from JCPDS #50-0653. b A
schematic representation of using the lever rule with a peak of
phase A (Co 3 O 4 here). The sample X lies in the coexistence
region such that extrapolating to where the area of the phase A
peak is zero gives a point B on the boundary of the layered
region. c The results of using the lever rule for samples along the
line from A 4 to LiCoO 2 , represented by the open circles (these
represent point X in b). The red circles (point B in b) are the
resulting points on the boundary of the layered region for samples
made at 800
◦ C and cooled at the regular rate, while the blue
triangles were obtained from quenched samples....................
52
xxiii
The MgO peaks were truncated at 500 cps and
∗ indicates their
positions. For ease of viewing, a polynomial background was fit
and subtracted from each scan. The vertical lines indicate peak
positions and relative intensities from the JCPDS database........
42
Fig. 3.7
a Peak areas as a function of temperature. Open symbols are for
the Li 2 CO 3 (002) peak. The closed triangles represent the large
stearate peak (divided by 30) obtained with ammonium
bicarbonate and heated in air. b Li x Ni 2−x O 2 crystallite size.
c Strain as a function of temperature. Error bars smaller than the
symbols were omitted ..................................................
44
Fig. 3.8
Lithium content measured by X-ray diffraction (XRD) versus the
amount dispensed .......................................................
44
Fig. 3.9
Calculated lithium content as a function of temperature. Closed
symbols indicate samples made by dispensing 20 μL of solution
as compared to 10 μL for the open symbols .........................
45
Fig. 4.1
The entire Gibbs triangles for samples heated to 800
◦ C in air and
quenched (a), or regular cooled (b). Sample A 4 is at the
composition Li 0.5 Mn 0.25 Co 0.25 and is referred to throughout the
text. Green dashed lines are tie-lines, solid red lines are
boundaries to single-phase regions while red dotted lines are
tie-lines bounding three-phase regions ...............................
50
Fig. 4.2
Stack of X-ray diffraction (XRD) patterns with fits and difference
plots obtained by heating to 800
◦ C and regular cooling. The
vertical lines indicate peaks from the JCPDS database, reference
#84-1634 for Li 2 MnO 3 and #74-1656 for Co 3 O 4 . The unlabeled
scans between A 4 and Li 2 MnO 3 are evenly spaced in composition
between the two end members. For clarity, only every third data
point is plotted...........................................................
51
Fig. 4.3
a Stack of X-ray diffraction (XRD) patterns for samples lying
between LiCoO 2 and point A 4 obtained by heating to 800
◦ C and
regular cooling. The red lines indicate the layered peaks while the
blue lines represent the positions of the Co 3 O 4 peaks. The
vertical lines for LiCoO 2 are from JCPDS #50-0653. b A
schematic representation of using the lever rule with a peak of
phase A (Co 3 O 4 here). The sample X lies in the coexistence
region such that extrapolating to where the area of the phase A
peak is zero gives a point B on the boundary of the layered
region. c The results of using the lever rule for samples along the
line from A 4 to LiCoO 2 , represented by the open circles (these
represent point X in b). The red circles (point B in b) are the
resulting points on the boundary of the layered region for samples
made at 800
◦ C and cooled at the regular rate, while the blue
triangles were obtained from quenched samples....................
52