Advanced Nano-Composite Lithium-Metal-Oxide Electrodes for High Energy Lithium-Ion ...€¦ · · 2014-11-11Advanced Nano-Composite Lithium-Metal-Oxide Electrodes for High Energy
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Advanced Nano-Composite Lithium-Metal-Oxide Electrodes for High Energy Lithium-Ion Batteries
Sun–Ho Kang
Chemical Sciences and Engineering Division
Argonne National Laboratory, Argonne, IL 60439
The 7th US-Korea Forum on Nanotechnology: Nanomaterials and Systems for Nano EnergySeoul, Korea, April 5-6, 2010
Diverse Applications of Li-ion Batteries
e g SoCalEdison A123e.g.,SoCalEdison-A12332 MWh LIB
Li i B tt iConsumer Electronics
Hearing devices
Neuro-stimulator
Pacemaker
Military Applications
Li-ion Batteries as power sources
Insulin pump
Bone growth stimulatorSmart Grid
(Utility-scale energy storage)
Medical Devices
Beagle 2
Spaceships and SatellitesTransportation
Miscellaneous(power tools, backup power, etc.)
e.g.,HEV, PHEV, EV, E-Bike
Why Li-ion Batteries?/l
)
400
350aller
/l)
400
350aller Secondary batteries sales (US)
Den
sity
(W
h/
300
250
sma Lithium Batteries
(LIB, LPB…)
Den
sity
(W
h/
300
250
sma Lithium Batteries
(LIB, LPB…)
ric
Ener
gy D
200
150
Ni-MH
Ni Znric
Ener
gy D
200
150
Ni-MH
Ni Zn
Vol
umet
100
50 lighter
Ni-ZnNi-Cd
Lead-AcidVol
umet
100
50 lighter
Ni-ZnNi-Cd
Lead-Acid
0 40 80 120 160 200Gravimetric Energy Density (Wh/kg)
00 40 80 120 160 200
Gravimetric Energy Density (Wh/kg)
0
Li‐ion battery is the battery chemistry of choice for future generations of energy storage systems for portable electronics, power tools, and electric vehicles. LIBstorage systems for portable electronics, power tools, and electric vehicles. LIB is also one of the candidates for utility‐scale electric energy storage systems.
LIB as Energy/Power Source for Transportation
Plug‐in Hybrid Electric Vehicles (PHEV)
A h b id hi l i h b i h b h d b i– A hybrid vehicle with batteries that can be recharged by connecting a plug to an electric power source (or by ICE, if necessary): all electric range of 10+ miles (current target: 40+ miles) g ( g )
– Impact on Energy, Economy, and Environmental Issues
• About half the gasoline consumed in the U.S. is consumed in the first 20 miles of daily travel of an automobile.
• Therefore, PHEV can significantly reduce foreign oil dependence as well as toxic and greenhouse gas emission
• President Obama’s speech to congress (24 Feb 2009): “We know the country that harnesses the power of clean, renewable energy will lead the 21st century. … New plug‐in hybrids roll off our assembly lines, but they will run on batteries made in Korea.”
• Significant, nation‐wide investment is being made by US (federal and state) government and commercial sectors for R&D activity as well as for establishing manufacturing industry (job creation)
DOE Targets for Energy Storage Systems for HEVs, PHEVs, and EVsand EVs
DOE Energy Storage Goals HEV(2010) PHEV(2015) EV(2020)
hCharacteristics Unit
Equivalent Electric Range miles N/A 10‐40 200‐300
Discharge Pulse Power kW 25‐40 for 10 sec 38‐50 80
l ( d ) kRegen Pulse Power (10 seconds) kW 20‐25 25‐30 40
Recharge Rate kW N/A 1.4‐2.8 5‐10
Cold Cranking Power @ ‐30 ºC (2 seconds) kW 5‐7 7 N/A
Available Energy kWh 0.3‐0.5 3.5‐11.6 30‐40Available Energy kWh 0.3 0.5 3.5 11.6 30 40
Calendar Life Year 15 10+ 10
Cycle Life Cycles 300k, shallow 3,000‐5,000, deep discharge
750, deep discharge
Maximum System Weight kg 40‐60 60‐120 300
Maximum System Volume l 32‐45 40‐80 133
Operating Temperature Range ºC ‐30 to 52 ‐30 to 52 ‐40 to 85
Selling Price @ 100k units/year $ 500‐800 1 700‐3 400 4 000Selling Price @ 100k units/year $ 500 800 1,700 3,400 4,000
No commercially available chemistries (cathode, anode, electrolyte, etc.) meet the DOE targets for PHEVs and EVs with 40+ electric rangetargets for PHEVs and EVs with 40+ electric range.
- Key issues: Energy, Life, Safety, and Cost
ApproachMulti‐institution team assembled to design synthesize characterize and modelMulti institution team assembled to design, synthesize, characterize, and model oxide structures for next‐generation electrode materials
Vehicle TechnologyVehicle Technology
DOE
Materials design and synthesisand synthesis
(CSE, Argonne)Electrochemistry(CSE, Argonne)
Structure Models(CSE, Argonne)
X-ray Absorption Spectroscopy
(APS, Argonne)
Electron Microscopy
(UIUC)Solid-State NMR
(Stony Brook)( , g )(Brookhaven)
( )(MIT)
What happens in a Li-ion cell?charge e-
charger
C
dischargee-
LiCoO2 Graphite
olle
ctor
Cu curr
Ch i Discharging
rent
corent col
electrolyte
Charging
Li Li+ + e-
Requires Energy
Discharging
Li+ + e- Li
Supplies Energy
Al c
urr llector
(+) (-)separator
Process reversibilityshould be ~100% for good cycle life
Active material in cathode is the source of lithium ions
LiMPO4(M=Fe, Ni, Co)
LiMn2O4LiMO2(M=Ni, Co, Mn, Li)
1D 2D 3D1D 2D 3D
Pros:Pros:Pros:• Fast Li motion through 3D
Li channel
• Low cost (Mn-based)
Cons:
• High theoretical capacity (~280 mAh/g)
Cons:St t l d t bili ti t
• Excellent safety
• Cost advantage (Fe)
Cons:Cons:
• Low theoretical capacity ( ~150 mAh/g)
• Capacity fading (Mn
• Structural destabilization at high SOC
• Highly oxidizing/unstable Ni4+ and Co4+ poor thermal safety
• Poor conductivity
• Low theoretical capacity (~170 mAh/g)
y g (dissolution, Jahn-Teller distortion)
thermal safety
Limitations of layered lithium metal oxides
LiMO2 (M=Ni,Co,Mn) Li(Li1/3Mn2/3)O2 (≡Li2MnO3)
TM plane TM plane
Similar structure to LiMO2
• One-third of M is replaced with Li
St d i b t Li+ d M 4+
For last two decades, layered LiMO2 (mostly LiCoO2) has been the positive electrode chemistry of choice for the LIBs for portable • Strong ordering between Li+ and Mn4+
Electrochemistry
• at <4.4 V vs. Li+/Li, Li2MnO3 is l t h i ll i ti
y pelectronics.
Limitations
Hi h t f C d Ni electrochemically inactive
• At >4.4 V vs. Li+/Li, lithium can be extracted together with oxygen:
Li2Mn4+O3 → Li2O + Mn4+O2 (460 mAh/g)
• High cost of Co and Ni
• Low practical conductivity (~150 mAh/g vs. ~280 theoretical capacity of LiCoO2) due to the structural instability at low Li content (Li/M<0.5)
Li2Mn O3 → Li2O + Mn O2 (460 mAh/g)
• However, the activated electrode tends to convert to spinel with cycling (same issue as LiMnO2)
• Conversion to spinel during cycling (LiMnO2)
• Highly unstable and oxidizing Ni4+ and Co4+ at charged state: thermal safety issues
Not a good electrode material for high energy Li-ion batteries with longevity!
Not a good electrode material for high energy Li-ion batteries with intrinsic thermal safety!
Nano-composite among Li2MnO3, LiMO2, and LiM’2O4
A unique approach of integrating lithium metal oxides with structural compatibility in nano‐composite structures:
(1) ‘layered‐layered’ electrodes with layered Li2MnO3 and LiMO2 components(1) layered layered electrodes with layered Li2MnO3 and LiMO2 components
(2) ‘layered‐layered‐spinel’ electrodes comprised of layered Li2MnO3, layered LiMO2 and spinel LiM’2O4
components.
MotivationMotivation
– Enhancing structural stability: integration of Li2MnO3 as a structural stabilizing agent in LiMO2 matrix to prevent structure collapse of the layered structure at low Li content
– Increasing capacity: activation of Li2MnO3 at high voltagesIncreasing capacity: activation of Li2MnO3 at high voltages
An example of layered-layered nano-composite structure
LiMO2 region Li2MnO3 region
Li2MnO3 regionLiMO2 region
Structural compatibility of Li2MnO3 and LiMO2: Li1.2Ni0.2Mn0.6O2
3)
XRD pattern Electron diffraction
ary
unit) (0
03
(104
)
m
ty (a
rbitr
a
01)
) 8) 10)
020)
C2/
m10
) C2/
m1)
C2/
m
Inte
nsi
(10
(006
)(0
12)
(015
)
(107
)(0
18 (11
(113
)
(0 (1(1
1-
Li2MnO3
10 20 30 40 50 60 70 80
2θ
Mostly LiMO2-like (rhombohedral, R-3m) feature with Li2MnO3-like (monoclinic, C2/m) characters (cation ordering peaks and diffuse streaks))Li1.2Ni0.2Mn0.6O2 ≡ 0.5Li2MnO3•0.5LiNi0.5Mn0.5O2
Structural compatibility of Li2MnO3, LiMO2, and LiM’2O4: Li Ni Mn O (y~1 88)
X-ray diffraction patterns
Li0.96Ni0.2Mn0.6Oy (y~1.88)un
it)
h
Li0.96Ni0.2Mn06OyLiMO2
(layered)+
arbi
trary
h h
hcalcined at 900 °C
S SS S
co+
Li2MnO3(layered with cation
ensi
ty (a 800 °C
700 °C
(layered with cation ordering)
+
10 20 30 40 50 60 70 80
Inte 700 C
LiM’2O4(spinel)
10 20 30 40 50 60 70 80
2θCuKα
Three‐component integrated structure
h: X-ray sample holder
co, cation ordering; s, spinel
Three component integrated structureLi0.96Ni0.2Mn0.6Oy ≡ 0.3LiNi0.5Mn1.5O4•0.7Li2MnO3•0.7LiMO2 (M=Ni0.5Mn0.5)
Nano-composite feature of Li0.96Ni0.2Mn0.6Oy:0.3LiNi0 5Mn1 5O4•0.7Li2MnO3•0.7LiMO2 (M=Ni0 5Mn0 5)0.5 1.5 4 2 3 2 ( 0.5 0.5)
HR TEM image
This HR TEM image demonstrates the structural integration of spinel (Fd 3m)This HR TEM image demonstrates the structural integration of spinel (Fd‐3m)
and layered (C2/m).
Nano-composite feature of Li1.2Co0.4Mn0.4O2:0 5Li MnO •0 5LiMO (M=Co)0.5Li2MnO3•0.5LiMO2 (M=Co)
Z contrast STEM image
View of transition metal planes along [001]MView of transition metal planes along [001]M
TM columns: bright-spots in imageLi columns: dark.
Honeycomb regions (hollow core = Li column) are Li2MnO3-like. Hexagonal regions (filled core
TM l ) LiC O lik N h= TM column) are LiCoO2-like. No sharp boundaries between honeycomb and hexagonal regions.
Li2MnO3Li2MnO3
X-ray absorption spectroscopy of 0.5Li2MnO3•0.5LiCoO2
Co EXAFS
Co-O
Co-TM0.5Li2MnO3•0.5LiCoO2Co-O bond distance ~ 1.91 ÅCo O bond distance 1.91 Å(same as in LiCoO2)
Co-TM data coordination is 5 4 +/-Co TM data coordination is 5.4 +/0.5 (6 in LiCoO2)
Exact phase matching of peaks in 4-Exact phase matching of peaks in 4-6 Å range (data not shown)
Co environment in 0.5Li2MnO3•0.5LiCoO2 appears very similar to LiCoO2 environment up to 7 Å.
X-ray absorption spectroscopy of 0.5Li2MnO3•0.5LiCoO2
Mn EXAFS
Mn-O 0.5Li2MnO3•0.5LiCoO2Mn-O bond distance ~ 1.89 Å
Mn-TM
Mn O bond distance 1.89 Å(same as in Li2MnO3)
Mn-TM data coordination is 4 2 +/-Mn TM data coordination is 4.2 +/0.5 (3 in Li2MnO3)
Exact phase matching of peaks in 4-Exact phase matching of peaks in 4-6 Å range (data not shown)
Mn environment in 0.5Li2MnO3•0.5LiCoO2 appears similar to Li2MnO3environment up to 7 Å.
Model for atomic arrangement in TM plane of 0.5Li2MnO3•0.5LiMO22 3 2
LiMO2-like2
Li2MnO3-like
An intimate mixture of LiMO2-like and Li2MnO3-like areas (~1-3 nm 2 2 3size) are present in 0.5Li2MnO3•0.5LiMO2
Electrochemistry of two-component systemLi Ni C M O Fi t l fil f lithi ll
5
V)
Li1.2Ni0.18Co0.10Mn0.52O2: First cycle profile of a lithium cell
LiMO2-like Li2MnO3-like
4
5ag
e (V
300
2
3
ell v
olta
2 0-4 6 V100
150
200
250
300
city
(mAh
/g)
LiCoO2
0
1Ce 2.0 4.6 V
0.1 mA/cm2
RT0 10 20 30 40 500
50
100
Cap
a
Cycle Number
0 100 200 3000
Capacity (mAh/g)Two step behavior during the first charge:
LiMO2-like region: LiMO2 → Li+ + MO2 + e-
Li2MnO3-like region: Li2MnO3 → 2Li+ + MnO2 + 1/2O2 + 2e- (O2 evolution confirmed by in situ DEMS)DEMS)Very high capacity during the subsequent discharge and excellent capacity retention
Li Ni M O Fi t l fil f lithi ll
Electrochemistry of three-component system
5
V)
Li0.96Ni0.2Mn0.6Oy: First cycle profile of a lithium cell
spinel
4
5ag
e (V
Li2MnO3 activation + spinel
2
3
ell v
olta
2 0-4 95 V150
200
250
300
ty (m
Ah/
g)
0
1Ce 2.0 4.95 V
0.05 A/cm2
RT0 10 20 30 40 500
50
100
Cap
acit
Cycle Number
spinel
0 100 200 3000
Capacity (mAh/g)
Three distinctive regions:LiMO2-like region, Li2MnO3-like region (activation), and spinel signatures
Very high capacity during the subsequent discharge and excellent capacity retention
Superior electrochemical property of the nano-composite electrode material to other materialselectrode material to other materials
Li1+xMn2-xO4
LiCoO5
V)
LiCoO2
Li(Ni1/3Co1/3Mn1/3)O2
layer-layer
4
tage
(V
y y layer-layer-spinel
3
ell V
olt
2
Ce
0 50 100 150 200 250
Capacity (mAh/g)
Capacity Retention and Rate Capability of Li1.2Ni0.25Mn0.75Oy
5
Cycling performance Rate performance
4
V)200
250
Ah/
g)
3
olta
ge (V
100
150
acity
(mA
2
Vo
Li cell2.0-4.95 V10 mA/g
3.5C 1C C/2350
100
Cap
a
900 oC 800 oC700 oC
0 50 100 150 200 2501
Capacity (mAh/g)
10 mA/g
0 10 20 30 40 500
Cycle Number
700 C
Beneficial impact of the spinel component in the structure– Excellent cycling performance (800, 900 °C samples) in spite of the very high cut‐off
voltagevoltage.– Good rate capability (~200 mAh/g at 1C rate).
SUMMARY
A novel concept of integrating lithium metal oxides with different
structures (but compatible) in nano‐scale has been adopted to design and
develop electrode materials for advanced high‐energy lithium‐ion
batteries.
Two component system– Two component system
– Three‐component system
Through advanced analytic techniques the atomic arrangement featuresThrough advanced analytic techniques, the atomic arrangement features
of the nano‐composite materials have been demonstrated.
The nano‐composite material exhibited outstanding electrochemicalThe nano composite material exhibited outstanding electrochemical
performance.
Possibility of using these nano‐composite electrode materials in PHEV y g p
batteries is under investigation.
The Argonne’s nano‐composite cathode materials have recently been
licensed to major chemical companies and battery companies.
Acknowledgement
Argonne National Laboratory
CSE Division: M. M. Thackeary, C. S. Johnson, D. P. Abraham, J. Bareno, G. y, , , ,Henriksen
APS: M. Balasubramanian – XAS
UIUC
C. H. Lei, I. Petrov – TEM
C. Carlton, Y. Shao-Horn – TEM
Department of Energy
Office of Basic Energy Sciences – ‘fundamental research’
Office of FreedomCar and Vehicle Technologies – ‘exploratory (BATT) and li d (ABRT) R&D’applied (ABRT) R&D’
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