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Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
SPring-8 5
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 20112
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 20113
6535 6540 6545 6550 6555 6560 65650.0
0.2
0.4
0.6
0.8
1.0
Abso
rban
ce
Energy / eV
LiMn2O4 Mn
Jahn-Teller (Mn3+)
LiMn2O4Mn
2Mn3+���2++Mn4+
Mg2+ Mn3+
Mn K-edge
LiMn2O4
LiMg0.02Mn1.98O4LiMg0.2Mn1.8O4
Mg2+ Mn K-edgeMn3+
Mn K-edge XANES Profiles of LiMgxMn2-xO4
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 20114
SiOC
XANES TEM
SiO XRD
SiO Si SiO2SiO2 Si
1830 1840 1850 1860 1870
SiO2
SiO
Si
Abso
rban
ce
Photon Energy / eV
Si K-edge XANES Profiles of Si Materials
SiO2 matrices(amorphous)
Si (111) 2nm
Si Particle (3nm)
High Resolution TEM Image of SiO
Si ultra fine particles(<20nm)
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 20115
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
350
400
450
500
550
600
'12'11'08'06'04 '10'09'07'05
Ener
gy D
ensi
ty /
WhL
-1
Calendar Year'03
→
Calculate from prismatic cell
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
300 400 500 600 700 800 9003.3
3.4
3.5
3.6
3.7
3.8
3.9
4.0
4.1
Specific Discharge Capacity / mAhcc-1Disc
harg
e Po
tent
ial /
V v
s Li
/Li+
0 500 1000 1500 2000 25001.6
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
LiCoO2
L4Ti5O12
LiMn2O4
LiNi1/3Co1/3Mn1/3O2
LiFePO4
Graphite
LiNi0.8Co0.15Al0.05O2
Li2.6Co0.4N
LiNiO2
LiVO2
CoSn Sn
SiOSi
Li
Cathode Materials Anode Materials
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 20118
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
Ni 4.2 V Li 4.2 V
Voltage profiles calculated using electrochemical density of state( ) ( )
i
iii x
xFRTx
FExE
-1ln2-2-1z-0
φ=
0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.02.8
3.2
3.6
4.0
4.4
4.8
5.2
x in LixMeO2
Pote
ntia
l /
V v
s. L
i/Li+
4.2
150 mAh g-1
High capacity
LiNiO2
LiCo3/4Ni1/4O2
LiCo1/4Ni3/4O2
LiCoO2
200 mAh g-1
T.Ohzuku and A.Ueda, J.Electrochem.Soc.,144, 2780(1997)
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
Ni 90% 4.2 V
LiCoxNi1-xO2 with x = ca.0.1 show the highest capacity
Ni/Co
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.00
100
120
140
160
180
200
220Re
char
geab
le c
apac
ity /
mAh
g-1
x in LiCoxNi1-xO2
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNiO2 Ni 90%
0 50 100 150 200 250
3
4
3
4
3
4
Capacity / mAh g-1
Pote
ntia
l /
V v
s. L
i/Li+
More than 200 mAh g-1 of rechargeable capacity
LiNi0.9Co0.1O2
LiNi0.8Co0.2O2
LiNiO2
Examined in lithium cell
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
0 100 200 300 400 50050
60
70
80
90
100
110Ca
paci
ty re
tent
ion
/
%
Cycle number / -
Prismatic Cell (463443)
Nominal capacity : ca. 850 mAhCurrent : 0.7 C rate (charging), 1 C rate(discharging)Voltage ranges : 2.5 to 4.2 V (n=3)
LiNi0.9Co0.1O2 / Graphite
LiNi0.9Co0.1O2
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
500
5002.5 V
DME
LIB
0 40 80 120 160 200 2402.0
2.5
3.0
3.5
4.0
4.5
Pote
ntia
l /
V v
s. L
i/Li+
Capacity / mAh g-1
LIB
Li
Li
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2 (TG, XRD)
10 20 30 40 50 60 70
LiNi0.9Co0.1O2
LiNi0.9Co0.1O2
a=2.8798 Åc=14.1435 Åc/a=4.911
a=2.8709 Åc=14.1530 Åc/a=4.930
I(003)/I(104)=1.22
I(003)/I(104)=0.97
(113
)(110
)(1
08)
(107
)
(105
)(1
04)
(102
)(006
)(101
)
(003
)
(CuKα)2θ / degree0 200 400 600 800 1000
5
4
3
2
1
0
Wei
ght l
oss
/
%
Temperature / oC
TG curves of LiNi0.9Co0.1O2 XRD patterns of LiNi0.9Co0.1O2
TG 800XRD 800 (900 ) I(003)/I(104) Li Ni
800Li Ni
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2 (XAFS)
8355 8360 8365 8370 8375
0.0
0.2
0.4
0.6
0.8
1.0
NiONi K-edge
Norm
aliz
ed a
bsor
banc
e /
-
Energy / eV
LiNi0.9Co0.1O2 LiNi0.9Co0.1O2 heated at 900oC for 6h in air
0 1 2 3 4 50
4
8
12
16
20
Ni - Ni
Ni - O
FT in
tens
ity
/ -
R / Å
LiNi0.9Co0.1O2 LiNi0.9Co0.1O2 heated at 900oC for 6h in air
rmal
i
@Spring-8(BL16B2)
Ni-O[ ] Ni-O[ ] Ni-O[ ]-Ni-O[ ] Ni-NiLiNi0.9Co0.1O2 1.922 Å 2.070 Å 0.148 Å 2.861 Å
LiNi0.9Co0.1O2 (heated at 900oC) 1.915 Å 2.049 Å 0.134 Å 2.873 Å
Ni-O[ ]
Ni-O[ ]
: O: Ni
Ni-O[ ]
Ni-O[ ]
: O: Ni
Ni K-edge XANES Profiles of Li 0.9Co0.1O2 FT of Ni K-edge spectra of Li 0.9Co0.1O2
Li Ni Ni2+
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
Ni2+
Ni2+
Ni2+
Ni2+ 0 50 100 150 200 2502.5
3.0
3.5
4.0
2.5
3.0
3.5
4.0
4.5
LiNi0.9Co0.1O2
Pote
ntia
l /
V v
s. L
i/Li +
Capacity / mAh g-1
LiNi0.9Co0.1O2
XRD Li NiXAFS Ni2+
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
Mg2+
Mn4+
LiNi0.9Co0.05Mn0.025Mg0.025O2
Mn2O3
Li2MnO3
Mn K edge
6530 6540 6550 6560 6570
0.0
0.2
0.4
0.6
0.8
1.0
Norm
aliz
ed a
bsor
banc
e /
-
Energy / eV
�Ni : 90%�Co3+ Mn4++Mg2+ LiNi0.9Co0.05Mn0.025Mg0.025O2
Ni LiMn4+ Mg2+
(3+)
(4+)Ni2+
XANES Profiles of LiNi0.9Co0.05Mn0.025Mg0.025O2
LiNi0.9Co0.05Mn0.025Mg0.025O2 Mn 4
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
0 100 200 300 400 50050
60
70
80
90
100
110
Capa
city
rete
ntio
n /
%
Cycle number / -
After charging at 4.2V in the cell with graphite
Heating rate; 2ºC/min
LiNi0.9Co0.1O2
LiNi0.9Co0.05Mn0.05O2
LiNi0.9Co0.05Mn0.025Mg0.025O2
LiNi0.9Co0.1O2
LiNi0.9Co0.05Mn0.05O2
LiNi0.9Co0.05Mn0.025Mg0.025O2
Prismatic Cell (463443)
Nominal capacity : ca. 850 mAhCurrent : 0.7 C rate (charging), 1 C rate(discharging)Voltage ranges : 2.5 to 4.2 V (n=3)
5
6
7
8
9
10
11
Capa
city
rete
ntio
n /
%After charging at 4.2V in the cell with graphite
Heating rate; 2ºC/min
LiNi0.9Co0.1O2
LiNi0.9Co0.05Mn0.05O2
LiNi0.9Co0.05Mn0.025Mg0.025O2
DSC Profiles Cycle ability
Mn, Mg60% 76%@500cycle
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
10 20 30 40 50 60 70
(113
)(1
10)
(108
)
(107
)
(105
)(1
04)
(102
)(0
06)
(101
)
(003
)
(CuKα)2θ / degree8350 8360 8370 8380
0.0
0.2
0.4
0.6
0.8
1.0
Norm
alize
d ab
sorb
ance
/
-
Energy / eV
500XRD
@spring-8
: Li1.0Ni0.9Co0.1O2500 : Li0.6Ni0.9Co0.1O2-x
XAFS(TEY)
50040 nm
Ni
NiO-like ICP
Ni K edge
Ni ?
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2
0 100 200 300 400 50050
60
70
80
90
100
110Ca
paci
ty re
tent
ion
/
%
Cycle number / -
LiNi0.9Co0.1O2
LiNi0.9Co0.05Mn0.025Mg0.025O2
Prismatic Cell (463443)
Nominal capacity : ca. 850 mAhCurrent : 0.7 C rate (charging), 1 C rate(discharging)Voltage ranges : 2.5 to 4.2 V (n=3)
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 201121
SiOC
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
Si-C
Reducing a volumetric expansion of Li-Si anodematerial for Li insertion
Concept for Porous Composite Particle
Discharge Charge
Cycling
Coatings Carbon material
Si
Pore
To use fine Si powder To granulate fine Si and carbon with poreTo coat composites with carbon
Improving cycleability of Si anode
����
SEM Image of Porous Si-C Composite
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
10 20 30 40 50 600
10
20
30
40
50
60
Expa
nsio
n Ra
te o
f Dia
met
er /
%
Porosity / %
Si/G
raph
ite
Si/C
F
Si/C
F/P
BAfter 1st chargeby 1Ah/cc
After 1st discharge
Expansion Rate of Porous Si-C Composite for Cycle
0 10 20 30 40 500.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
Capa
city
/ Ah
g-1
Cycle Number
�������� ���� ����(Porosity: 52vol%)
�������� �Gr(Porosity: 30vol%)
Mixture Si and C
Graphite
Cycle Properties of Porous Si-C Composite
Si-C
50 ���Si
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
Si
0 5 10 15 20 25 30 35 40 45 500.0
0.2
0.4
0.6
0.8
1.0
1.2Ca
paci
ty /
mAh
Cycle Number
1000nm
300nm
100nm25nm
→ →→
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
CoatingsCarbon material
Pore
C bo eC eeAmorphous matrices (X)
Nano Si crystalline< 20nm
Nano-Si can show improved cycleability without crumbling.
Amorphous matrices can reduce the expansion rate for cycle.
Cycling
Nano Li-Si crystalline
Discharge Charge
Active particle(nano-Si/amorphous)
SiO
Si 2
→ → → →
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
1820 1830 1840 1850 1860 1870 1880
Abso
rban
ce
Photon Energy / eV
SiO2
Si
SiO
Si X XANES
SiO = Si + SiO2 X
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
20nm
Si (111)
2nm
Si: 3nm
SiO2 matrices(amorphous)
Si ultra fine particles(<20nm)
Schematic Image of SiO
Reference: Y.Nagao, H. Sakaguchi, T. Esaka, et. al., J. Electrochem. Soc., 151, P.1572 (2004).A.Hohl et al., J. Non-Cryst. Solids, 320, P.255 (2003).
SiO2 matrices
Si crystalline
SiO Si SiO2
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.40.0
0.5
1.0
1.5
2.0Po
tent
ial /
V v
s Li
/Li+
Capacity / Ahg-1
1st Efficiency= 73%
1st Efficiency= 54%
SiO-C
SiO-C Composite
Mixture SiO and Gr
SiO C � 20%UP
��
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
0 20 40 60 80 10020
40
60
80
100
Capa
city
Ret
entio
n / %
Cycle Number
Positive electrode: LiCoO2+LiNi1/3Co1/3Mn1/3O2Current: 0.5CTemp.: 23
SiO-C Composite
Mixture SiOand Graphite
Si-C Composite
SiO C � %UP
SiO-C
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
(Assumption)SiO + 6.4Li ������4.4 + Li2O (irreversible phase)
(Theoretical Value)Charge Capacity = 3880mAh/g1st Efficiency = 68%
ExperimentalResults
Charge Capacity/ mAhg-1
Discharge Capacity / mAhg-1
1st Efficiency / %
(10mV 1.5V)
SiO-C Composite(per weight of SiO)
ggg
1200(2560)
ggg
872(1869)
73
Mixture SiO + Gr(per weight of SiO)
( )1382
(2570)
( )740
(1388)54
Inconsistency
SiO Li2O
Why does the first efficiency of SiO-Ccomposite increase ?
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
Discharge to 3V (Li/Li+)0.25mA/cm2 CC
(NMR: 2.5V CC)
FIB system in ArSTEM system in vac.using atmosphere blocking cellMeasuring in vac.
FFFFSSSSSSuuM
Si
Charge to 10mV (Li/Li+)0.25mA/cm2 CCCV
(until 0.025mA/cm2)
(NMR: 4.2V CCCV)
Li-Si-Omatrices
Extract the sample in Ar→ Wash with DEC→ Dry and transfer to …
XANES system in Arusing Ar flow bagMeasuring in vac.
NMR system in Arusing atmosphere blocking cellMeasuring in Ar
Charge
Discharge
Structural AnalysisCharge & Discharge
XANES and STEM-EELS→ Li cell
NMR→ Full cell
XXXXuuM
NNNNuuMDDii hh
Li-Si-Omatrices
LixSi
CCChhh
SiO2matrices
Si
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
80 60 40 20 0 -20 -40 -60 -80
Inte
nsity
Chemical Shift / ppm50 0 -50 -100 -150
Inte
nsity
Chemical Shift / ppm
SiO2/ LixSi
Si / Li2SiO3
Li4SiO4
Li-Si-O
LixSi
29Si NMR spectra of SiOC 7Li NMR spectra of SiOC
Initial
Charge
Discharge
SiO NMRLi4SiO4
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
50nm 90 100 110 120 130 140 150
Inte
nsity
Energy / eV
EELS spectra of SiOC
( I )( II )
( I )
( II )Si4+Si0
STEM image of SiOC (discharge state)
SiO STEM-EELS
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
Li4SiO4 Li4Si
Li4SiO4
Li2SiO3
Li4SiO4
Li4SiO4
ChargeInitial
SiO2Si
Li4.4Si
LiSiO Li2SiO3
Si Discharge
Lithium ion conductor
SiO Li
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
2Si + 8.8Li ��������4.4)2SiO2 + 8.4Li ������4.4 + Li4SiO4 (irreversible phase)
Causing an increase in Si sizeCausing a superior battery properties
SiO Li4SiO4
��
Charge Capacity (Qc) and First Efficiency (E1st) of SiO
Experimental Results Mixture SiO and C: Qc= 2560mAh/g(SiO) E1st= 54%SiO-C Composite: Qc= 2570mAh/g(SiO) E1st= 73%
Calculated Value (from Analysis)Reaction 4SiO + 17.2Li ��������4.4) + Li4SiO4
Qc= 2610mAh/g E1st= 76.7%
GoodAgreement
Hitachi Maxell Energy, Ltd. – Confidential and Proprietary August 29, 2011
LiNi0.9Co0.1O2 SiOC
LiNi0.9Co0.1O2 Ni2+ Li
LiNi0.9Co0.1O2
Mn MgLiNi0.9Co0.1O2
SiO Si SiO2 SiO2 Si
SiO Li-Silicate
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