design of stoichiometric layered potassium transition metal ......h. kim et al. adv. energy mater....
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Design of Stoichiometric Layered Potassium
Transition Metal Oxide for K-Ion Batteries
Haegyeom Kim,
Post-doc Fellow in Ceder group
Materials Sciences Division
Lawrence Berkeley National Laboratory
Abstract #: A05-383 October 03 2018 08:00-08:20
Download these slides at http://ceder.berkeley.edu 1
H. Kim et al. Chem. Mater. ASAP (DOI: 10.1021/acs.chemmater.8b03228)
2
- Stoichiometric Layered Potassium Transition Metal Oxide for Re-chargeable
Potassium Batteries.
Chemistry of Materials. 30, 6532 (2018)
- A new strategy for high voltage cathodes for K-ion batteries: Stoichiometric KVPO4F.
Advanced Energy Materials. 1801591 (2018)
- Recent progress and perspective in electrode materials for K-ion batteries.
Advanced Energy Materials. Vol. 8, 1702384. (2018)
- Investigation of potassium storage in layered P3-type K0.5MnO2 cathode.
Advanced Materials. Vol. 29, 1702480. (2017)
- K-ion batteries based on a P2-type K0.6CoO2 cathode.
Advanced Energy Materials, Vol. 7, 1700098 (2017)
3 H. Kim et al. Adv. Energy Mater. 2018, 8, 1702384
0
20,000
40,000
60,000
Potassium
carbonate
790
USD / Ton
USGS Report (2018)
58,643
USD / Ton
13,900
USD / Ton
Cobalt
oxide
Lithium
carbonate
Pri
ce
(U
SD
/ T
on
)
Sodium
carbonate
152
USD / Ton 0
10,000
20,000
30,000
40,000
50,000
60,000
70,000
Fe Co Ni
10,144
58,643
< 100
7,40011,464
Pri
ce
(U
SD
/ T
on
)
Ti V Cr Mn
8,600
Potassium is earth abundant and has lower price than lithium.
K-ion battery system does not require expensive Co element.
Ceder Group
Standard
potentials
(vs. SHE)
Li/Li+
Na/Na+
K/K+
Aqueous -3.04 -2.714 -2.936
PC solvent -2.79 -2.56 -2.88
EC/DEC solvent
(relative value)
0.0 0.3 -0.15
Komaba et al. Electrochem. Commun. 2015, 60, 172,
Lower standard redox potential of alkali ions
Potentially higher working voltage of battery system
Working voltage
Standard redox potential of A/A+
Redox potential of electrode
4
Ceder Group
Komaba et al. Electrochem. Commun. 2015, 60, 172,
Graphite can store and release K ions, but not Na.
It indicates we already have a good anode material!!!
5
Ceder Group
Recently, K-ion batteries attract much attention.
6
2004 2010 2012 2014 2016 20180
10
20
30
40
50
Nu
mb
er
of
pap
ers
Year
Web of science
Accessed, August 15 , 2018
Ceder Group
Transition metal component
High redox activity
2-dimensional ion migration pathways
Good rate capability
Rigid oxide framework
Good cycle stability
Xiang et al. J. Electrochem. Soc. 2015, 162, A1662
Layered transition metal oxides (AxMO2, A= Alkali ion and M=
Transition Metal) have been studied as cathode materials for Li-, Na-,
and K-ion batteries.
7
Ceder Group
8
Many stoichiometric LiMO2 and NaMO2 compounds have been used as
cathodes for Li- and Na-ion batteries.
LiCoO2
Y. –I. Jang et al. J. Electrochem. Soc. 2002, 149, A1442 X. Ma et al. J. Electrochem. Soc. 2011, 158, A1307
NaMnO2
Ceder Group
9
K-layered compounds reported to date are K-deficient compositions.
KxMO2 (0.3 ≤ x ≤ 0.7, M = transition metal)
Composition Reference
K0.3MnO2 JES 163 A1295 (2016)
K0.7Mn0.5Fe0.5O2 Nano Lett. 17, 1, 544 (2016)
K0.6CoO2 Adv. Energy Mater. 1700098 (2017)
K0.5MnO2 Adv. Mater. 29, 1702480 (2017)
K0.67Ni0.17Co0.17Mn0.66O2 Electrochem. Commun. 82, 150 (2017)
K0.41CoO2 Chem. Commun., 53, 3693 (2017)
K0.45MnO2 Chem. Eng. J. 356, 53 (2019)
Ceder Group
10
K-transition metal oxides have been investigated as cathodes
for K-ion batteries.
P2-K0.6CoO2 P3-K0.5MnO2
H. Kim et al. Adv. Energy Mater. 1700098 (2017) H. Kim et al. Adv. Mater. 170248 (2017)
1st cycle
Ceder Group
11
P2-K0.6CoO2 P3-K0.5MnO2
H. Kim et al. Adv. Energy Mater. 1700098 (2017) H. Kim et al. Adv. Mater. 170248 (2017)
In the practical cells, K ions should be brought from cathodes.
K-deficient cathode requires pre-potassiation process.
This capacity needs to come from anode or pre-potassiation process.
1st cycle
Ceder Group
12
Most transition metals cannot form stoichiometric
layered structure (KMO2) because of large K ion size.
But, KScO2 and KCrO2 can be stabilized in layered
structure.
KScO2: due to large ionic size of Sc3+.
KCrO2: why?
Most stable structure:
Non-layered
H. Kim et al. Chem. Mater. 18, 6532
Not stable O3
Ceder Group
13
0.0
0.5
1.0
En
erg
y (
eV
/f.u
.)
FeMn
Cr NiCo
O= Octahedral, T= Tetrahedral, Py= Pyramidal sites
O T PyO T PyO T PyO T Py
O T Py
In KMO2 composition, Cr3+ strongly prefers
occupying octahedral site.
In contrast, Mn3+, Co3+, and Ni3+ prefers pyramidal
sites and Fe3+ prefers tetrahedral sites.
2D K arrangements
3D K arrangements
3D K arrangements
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
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Cr3+ has d3 electron configuration and is thus more
stabilized in octahedral sites than in other sites.
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
15
Mn3+ has d4 electron configuration and thus can be
stabilized in pyramidal sites.
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
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Fe3+ has d5 electron configuration and thus can be
stabilized in tetrahedral sites.
Competition between K+-K+ interaction
vs. site preference of transition metal
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
17
Stoichiometric O3-type KCrO2 is synthesized.
ICP: K/Cr = 1.02
The particle size: ~1 µm
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
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K metal anode
0.7 M KPF6 in EC/DEC electrolyte
At 5 mA/g, KCrO2 delivers a reversible capacity ~92 mAh/g.
Multiple plateaus indicate successive phase transition as a function of K
content.
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
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KCrO2 retains ~60 mAh/g after 100 cycles.
KCrO2 provides a moderate rate capability: 30 mAh/g at 500 mA/g
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
0 20 40 60 80 100 120 1400
1
2
3
4 2nd
Vo
lta
ge
(V
)
Capacity (mAh g-1)
1st
0 2 4 6 8 10
0
50
100
Re
ten
tio
n (
%)
Cycles
20
Practical feasibility of O3-type KCrO2 cathode was demonstrated in a full
cell with a graphite anode.
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
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4 3 2 1
0
20
40
60
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0
20
40
0.5
0.6
0.7
0.8
0.9
5 10 15 20 25 13 16 18 20
Two theta (Deg., Mo.)
Cha
rge
D
isch
arg
e
O3 (104)
O’3 (20-2) O’3 (111)
P3(015)
P’3 (201)
P’3 (11-2)
O3 (104)
P’3 (201)
P’3 (11-2)
P3(015)
O’3 (20-2)
O’3 (111)
P3(015)
P3(015)
P’3 (201)
P’3 (11-2)
P’3 (201)
P’3 (11-2)
Tim
e (
Ho
urs
.)
Voltage (V vs. K)
Al peak
x i
n K
xC
rO2
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
22
4 3 2 1
0
20
40
60
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0
20
40
0.5
0.6
0.7
0.8
0.9
5 10 15 20 25 13 16 18 20
Two theta (Deg., Mo.)
Cha
rge
D
isch
arg
e
O3 (104)
O’3 (20-2) O’3 (111)
P3(015)
P’3 (201)
P’3 (11-2)
O3 (104)
P’3 (201)
P’3 (11-2)
P3(015)
O’3 (20-2)
O’3 (111)
P3(015)
P3(015)
P’3 (201)
P’3 (11-2)
P’3 (201)
P’3 (11-2)
Tim
e (
Ho
urs
.)
Voltage (V vs. K)
Al peak
x i
n K
xC
rO2
Upon K extraction, (006) peak moves to lower angle, which indicates
expansion of c-axis.
It recovers after K insertion, indicating reversible reaction.
O3 (006)
Ceder Group
23
4 3 2 1
0
20
40
60
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0
20
40
0.5
0.6
0.7
0.8
0.9
5 10 15 20 25 13 16 18 20
Two theta (Deg., Mo.)
Cha
rge
D
isch
arg
e
O3
O’3
P’3
Tim
e (
Ho
urs
.)
Voltage (V vs. K)
Al peak
x i
n K
xC
rO2
Upon K extraction, successive phase transition of
O3-O’3-P’3-P3-P’3-P3-O3 is observed.
P3
P’3
P3
O3
P’3
P3
P3
P’3
O’3
Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
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4 3 2 1
0
20
40
60
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0
20
40
0.5
0.6
0.7
0.8
0.9
5 10 15 20 25 13 16 18 20
Two theta (Deg., Mo.)
Cha
rge
D
isch
arg
e
O3 (104)
O’3 (20-2) O’3 (111)
P3(015)
P’3 (201)
P’3 (11-2)
O3 (104)
P’3 (201)
P’3 (11-2)
P3(015)
O’3 (20-2)
O’3 (111)
P3(015)
P3(015)
P’3 (201)
P’3 (11-2)
P’3 (201)
P’3 (11-2)
Tim
e (
Ho
urs
.)
Voltage (V vs. K)
Al peak
x i
n K
xC
rO2
Upon K extraction, successive phase transition of
O3-O’3-P’3-P3-P’3-P3-O3 is observed. AxCrO2 ( A = Na and K)
x = 0.0 0.25 0.5 0.75 1.00
O’3 P’3
KxCrO2
NaxCrO2
O3
O3
O’3
P’3
P3
P’3
P3 O3
x ~ 0.43
x ~ 0.5
Strong K+-K+ interaction leads to
strong K+/vacancy ordering in KxCrO2 Ceder Group
H. Kim et al. Chem. Mater. 18, 6532
Less screening of electrostatics between K ions by oxygen results in
strong K+/vacancy ordering at given K concentrations, forming
remarkable amount of phase transitions.
25
Alkali ions
Transition
metals
Oxygen
LixCrO2 NaxCrO2 KxCrO2
Ceder Group
In KMO2 system, strong K+-K+ interaction destabilizes the
layered structure.
Stoichiometric KCrO2 can be stabilized in layered structure
because of strong octahedral site preference of Cr3+.
Stability of stoichiometric KMO2: Competition between K+-K+
interaction vs. site preference of transition metal.
KCrO2 delivers a reversible capacity of ~92 mAh/g.
KxCrO2 cathode goes through reversible multiple phase
transitions: O3-O’3-P’3-P3-P’3-P3-O3
26
Gerbrand Ceder,
Chancellor’s Professor
Department of Materials Science and Engineering
27
Thanks to
Dr. Dong-Hwa Seo
Prof. Alexander Urban
Dr. Jinhyuk Lee
Dr. Deok-Hwang Kwon
Prof. Shou-Hang Bo
Tan Shi
Joseph Papp
Prof. Bryan McCloskey
Thank you
Download these slides at http://ceder.berkeley.edu
28
H. Kim et al. Chem. Mater. 30, 6532 (2018)