WP 4 - Tailored precursors and active electrode materials - BATCircle
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WP 4 - Tailored precursors and active electrode materials Research highlights of the University of Oulu Research group: U. Lassi, M. Hietaniemi, P. Tynjälä, P. Laine, T. Hu, Y. Wang, I. Kervinen, T. Kauppinen, T. Vielma, Y. Lin, T. Tuovinen Organization: University Of Oulu BATCircle final seminar 11.3.2021
Overview of research activities
Co-precipitation of high-nickel precursors or lithium- Improved characterization tools for precursors
rich cathodes and electrodes
Improved lithiation processes for high-nickel NMCs, Use of secondary material flows in co-
precursor effect on lithiation, role of washing, wet/dry precipitation, role of impurities, reuse of
lithiation sodium sulphate
Sustainable pouch cell assembling
-new approaches to material-efficient coating
-use of greener solvents, additives and binders
Improved characterization tools for precursors and electrodes
• Energy filtered transmission electron microscopy (EFTEM) with scanning transmission
electron microscopy (STEM)
Samples preparation by FEI Helios DualBeam FIB+FESEM+STEM+EDS
720000
OKa
0. 5 µm IMG1 0. 5 µmIMG1(frame1) 0. 5 µm C K 640000
NiLa
560000
NiKa
480000
Counts
400000
PtMr
320000
NiKb PtLl
PtMa PtMb
240000
NiLl
NiKesc
CKa
PtMz
PtM1
PtLa
160000
80000
0. 5 µm O K 0. 5 µm Ni K 0. 5 µm Pt M 0
0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00
keV
Improved characterization tools for precursors and electrodes
• Energy filtered transmission electron microscopy (EFTEM) with scanning
transmission electron microscopy (STEM)
TEM JEOL JEM-2200FS
2
1 2
3
4
1
3 4
Improved characterization tools for precursors and electrodes
• XPS (X-ray Photoelectron Spectroscopy), also known as ESCA (Electron Spectroscopy
for Chemical Analysis)
Thermo Fisher Scientific ESCALAB 250Xi XPS System
MHLSC 17 and MHHSC 17 WD
Column1 Li/Me O/Me Ni mol% Co mol% Mn mol% Co(III)/Co(II) Mn(IV)/Mn(II) Ni(II)/Ni(I)
MHLSC-17 2,3 5,4 35,9 18,6 45,5 0,8 0,4 0,3
MHLSC-17 WD 0,7 1,8 40,0 17,8 42,2 0,9 0,3 0,3
Washing process dramatically decreased the Li concentration at the surface.
Task 4.1 Co-precipitation of lithium-rich layered oxide materials • M.Sc. thesis of Yufan Wang • Objective: This work was expected to synthesis layered Li-rich Mn-based cathode material by two-step co- precipitation and to understand the structure, morphology, and electrochemical performance of LLOs. • Approach • Li1.2Mn0.54Ni0.13Co0.13O2 (= 0.5Li2MnO3 • 0.5 LiNi1/3Co1/3Mn1/3O2) as target material. • To synthesis precursors by hydroxide co-precipitation • The sample was prepared using lithium sources Li2CO3 and LiOH, reaction temperature and time in lithiation process had been studied. • The effect of lithium content on structure and electrochemical performance of LLOs was investigated. WP 4 Presenter: Prof. Ulla Lassi, University of Oulu
Task 4.1
Co-precipitation of lithium-rich layered oxide materials
Highlights
• Layered lithium-rich oxides are one of the most 350
potential cathode materials for future LIBs, if L10-W Charge
synthesis can be done in the industrial-scale. 300 L10-W Discharge
Specific capacity (mAh g-1)
• Layered Li1.2Mn0.54Ni0.13Co0.13O2 was successfully
250
synthesized.
• High specific capacity reached 279.65 mAh g-1, 200
and Coulombic efficiency was 82.8% at 2.0-4.8V.
• After 30 cycles, capacity retention was 82.9% 150
(231.92 mAh g-1 at 0.1C) at 2.0-4.8V
100
• Optimized synthesis conditions:
- Dense, spherical particles, high tap density 50
0 5 10 15 20 25 30
- Chemical composition
Cycle number
- Detailed understand electrochemical
performance of LLOs, e.g., rate capability, Yufan Wang, Co-precipitation of lithium-rich layered oxide
voltage decay, etc. materials, M.Sc. thesis, University of Oulu, 2021
Task 4.1 Effect of precursor particle size and morphology on lithiation of NMC622 Highlights • Key issue affecting the capacity and cyclability of NMC622 is the Li/Me ratio • Effect of precursor quality on the energy density was also studied • Low density precursor does not lower the capacity (if sufficiently lithiated) • Highly porous precursor can be lithiated faster than traditional large wide span materials • It has also low cation mixing and good crystallinity • However, the volumetric energy density of porous material is low after lithiation Hietaniemi, M., Hu, T., Välikangas, J., Niittykoski, J., Lassi, U. (2021) Effect of precursor particle size and morphology on lithiation of Ni0.6Mn0.2Co0.2(OH)2, revised
Task 4.1
Comparing single-crystal and polycrystalline NCM622
Single crystal Polycrystalline
• Several precursors were successfully
lithiated (one-step or two-step) to single
crystal morphology which has been
claimed in the literature to improve the
capacity of NMC.
• PC materials have higher initial capacity
• Electrode density is better for SC except
for large wide span
• Washing process dramatically decreased
the Li concentration at the surface.
• There is a precursor effect in single crystal
lithiation. Two step heating only beneficial
for low density precursor.
Hietaniemi, M., Hu, T., Välikangas, J., Niittykoski, J., Singh, H., Lassi, U. (2021) Effect of NMC622 precursor in single crystal
lithiation, manuscript
Task 4.1
Long term cycling comparison of SC and PC
Pouch cell cycling of single crystal and polycrystalline
Highlights samples
• Successful single crystal lithiation of NMC622 180
160
• Contrary to earlier literature observations, single
Discharge capacity (mAh/g)
140
crystal lithiation seems not to improve the
120
capacity or cyclability of NMC622
100 PC-12 (10h)
• Washing has clear effect on the electrochemical 80 PC-7 (10 h)
properties of NMC622 60
SC-12 (10 h)
SC-13 (3h+7.7h)
40
20
0
0 100 200 300 400 500 600 700 800
Cycle number
Hietaniemi, M., Hu, T., Välikangas, J., Niittykoski, J., Singh, H., Lassi, U. (2021) Effect of NMC622 precursor in single crystal
lithiation, manuscriptTask 4.1
Precipitation of cobalt-free Ni(OH)2 precursor; Effect of temperature
- The most homogeneous particle size distribution was achieved by
using precipitation temperature of 40°C.
- Higher precipitation temperatures resulted in decreased homogeneity
of the particles as well as the breakage of the particles (60°C)
- The highest tap density value of the lithiated product was achieved
by using precursor precipitated at 40 °C.
Precip. D10 D50 D90 Tap density
temp. (µm) (µm) (µm) (g/cm3)
40 °C 7.68 10.9 15.5 2.69
50 °C 6.31 9.45 14.1 2.38
60 °C 7.61 11.3 16.8 2.40
Välikangas, Juho; Laine, Petteri; Hietaniemi, Marianna; Hu, Tao; Tynjälä, Pekka; Lassi, Ulla (2020) Precipitation and Calcination
of High-Capacity LiNiO2 Cathode Material for Lithium-Ion Batteries. Applied sciences 10 (24), 8988.
https://doi.org/10.3390/app10248988Task 4.1
Synthesis of LNO with improved electrochemical performance
Highlights
• The LiNiO2 calcination temperature was optimized to achieve a
high initial discharge capacity of 231.7 mAh/g (0.1 C/2.6 V) with the
first cycle efficiency of 91.3%.
• This was one of the best results reported for LNO
Välikangas, Juho; Laine, Petteri; Hietaniemi, Marianna; Hu, Tao; Tynjälä, Pekka; Lassi, Ulla (2020) Precipitation and Calcination
of High-Capacity LiNiO2 Cathode Material for Lithium-Ion Batteries. Applied sciences 10 (24), 8988.
https://doi.org/10.3390/app10248988Task 4.1
Coating and doping of LNO and NMC811
- Well controlled particle morphology and particle size
distribution during co-precipitation Highlights
- Desired tap density of the precursor • Highly homogeneous spherical precursor material with
- Effect of washing good electrochemical performance was synthetized.
- Several (bimetallic) dopings/coatings were done for • Low-level coating (1 wt%) has the larger influence on
NMC811 and LNO the battery cell performance than the low-level doping (1
wt%).
- Coatings were done with 0.1-5 wt% for LNO
Laine, Petteri; Välikangas, Juho; Kauppinen, Toni; Hu, Tao Tynjälä, Pekka; Lassi, Ulla (2021) Synergistic effects of low-
level magnesium and chromium doping on the electrochemical performance of LiNiO2 material, manuscript.Task 4.1
Coating and doping of LNO and NMC811
- Titanium oxide and zirconium oxide co-precipitated from isopropoxide/propoxide on the surface of
Ni(OH)2 precursor material
- The aim is to form a protective surface layer during the lithiation
- Near full encapsulation at 2 mol-% (4 and 8)
Laine, Petteri; Välikangas, Juho; Kauppinen, Toni; Hu, Tao Tynjälä, Pekka; Lassi, Ulla (2021) The influence of titanium and
zirconium doping and coating methods on the electrochemical performance of LiNiO2, manuscript.Task 4.1
Coating and doping of LNO and NMC811
Highlights
• LiNiO2 (LNO) was coated with Al2O3 (and other coatings) with 1-5
wt%. Coating improved the stability and cyclability of LNO.
• Results showed that high nickel material cyclability can
be improved by optimization of lithiation process (temperature),
which can be done clearly at lower temperatures.
• Coated, cobalt-free LNO is one of the most potential cathode
materials for future LIBs, and it can be produced in the industrial-
scale.
Välikangas, Juho; Laine, Petteri; Tanskanen, Pekka; Hu, Tao; Tynjälä, Pekka; Lassi, Ulla (2021)
Effect of coating (Al, Sc etc.) on the capacity and cyclability of LNO, manuscriptTask 4.1 Fundamental knowledge related to solubilities of CoSO4 (aq) and NiSO4 (aq) and related solid hydrates Akilan, Vielma et al. (2020) Volumes and Heat Capacities of the Cobalt(II), Nickel(II), and Copper(II) Sulfates in Aqueous Solution, J. Chem Eng Data 65(9), 4575-4581 Vielma, T. (2021) Thermodynamic model for CoSO4(aq) and the related solid hydrates in the temperature range from 270 to 374 K and at atmospheric pressure, Calphad 72, 102230
Task 4.3
Reuse of sodium sulphate residue
Metal concentrations of the pickling solutions
Sample Ni (mg/L) Fe (mg/L) Cr (mg/L) Pb (mg/L)
SE (Undil.) 175 ± 5 - - -
SE (after p.) 44 ± 1 24 ± 1 0.73 ± 0.04 7.5 ± 0.4
PE (after p.) 0.44 ± 0.1 21± 1 0.63 ± 0.03 8.9 ± 0.5
Average current efficiency of the pickling
Sample Average Ieff STDev
1) 2) SE 42.2 3) ± 0.2
• Comparison of sulfate solution from nickel hydroxide PE 36.5 ± 1.1
co-precipitation process (SE) and pure sodium
sulfate (PE) at pH 4. Average decrease in surface O/Cr m-%
• Slightly better pickling results in all measurements Sample Average Average
ΔO (m-%) ΔCr (m-%)
for recycled sulfate solution.
SE -4 -7
• Possible increase due to ammonia residue in the SE
used to control pH. PE -3 -4
Tuovinen T., Tynjälä P., Vielma T. & Lassi, U. (2021) Utilization of sodium sulphate side stream
from battery chemical production in the neutral electrolytic pickling, manuscriptTask 4.3
Use of secondary material flows
• Impurities in feed solutions Impurity concentrations of the precursor precipitates
• 1 (Ca 3.5 mg/l, Fe 1.4 mg/l, ZnTask 4.3
Use of secondary material flows
MPNCM-3 First cycle charge and discharge
MPNCM-2 4,5
MPNCM-1
4
Intensity (a.u.)
3,5
Voltage V
MPNCM-1
MPNCM-2
3
MPNCM-3
2,5
0 20 40 60 80 100 120 140
2
2 Theta (deg) -30 20 70 120 170 220
Specific capacity mAh/g
Kauppinen T., Laine, P., Välikangas, J., Salminen, J., Lassi, U. (2020), Co-
precipitation of NCM 811 from manganese sulfate obtained from anode
sludge: Effect of impurities on the battery cell performance, manuscriptTask 4.3
Use of secondary material flows
190,0
185,0
180,0 MPNCM-1
Specific capacity (mAh/g)
175,0 MPNCM-2
170,0 MPNCM-3
165,0
160,0
155,0
150,0
145,0
0 200 400 600 800 1000
Cycle number
Kauppinen T., Laine, P., Välikangas, J., Salminen, J., Lassi, U. (2020), Co-
precipitation of NCM 811 from manganese sulfate obtained from anode
sludge: Effect of impurities on the battery cell performance, manuscriptConclusions
• Co-precipitation of different NMC precursors was studied
• For high-nickel precursors, coating/doping would be needed
• Lithiation procedure is also different and should be optimized
• Development of high-voltage cathode materials require new type of
electrolytesThanks for Your attention! Thanks to researchers and collaborators!
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