Ola Nilsen, Yang Hu, Jonas Sottmann, Knut B. Gandrud, Pushpaka Samarasingha, Annina Moser, Helmer Fjellvåg. Electrons in motion

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1 Ola Nilsen, Yang Hu, Jonas Sottmann, Knut B. Gandrud, Pushpaka Samarasingha, Annina Moser, Helmer Fjellvåg Electrons in motion

2 NAFUMA Nanostructured Functional Materials Cathode Electrolyte Anode

3 NAFUMA Nanostructured Functional Materials Powder In situ Thin film

4 The motion Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 or Li 2 Mn 3 NiO 8? MoO 3 Preussian blue Na x Mn[Fe(CN) 6 ] y Thin and solid

5 The motion Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 or Li 2 Mn 3 NiO 8? LiNi 0.5 Mn 1.5 O 4 = 5 V The material exist with varying degrees of cation disorder in the spinel structure, where the disordered Fd-3m structure show a higher capacity over the ordered P structure.

6 Disordered spinel; Fd-3m Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 Cu ka X-ray data Li 2 Mn 3 NiO 8 Ordered spinel, P Mn, Ni ordering

7 Disordered spinel; Fd-3m Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 Neutron data Li 2 Mn 3 NiO 8 Ordered spinel, P Mn, Ni ordering

8 Disordered spinel; Fd-3m Neutron data Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 Synthesis at low-t give a disordered spinel with respect to Mn/Ni. Intermediate temperatures and up (700 o C) give complete Mn-Ni ordering Li 2 Mn 3 NiO 8 Ordered spinel, P Mn, Ni ordering

9 Disordered spinel; Fd-3m Neutron data Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 Synthesis at low-t give a disordered spinel with respect to Mn/Ni. Intermediate temperatures and up (700 o C) give complete Mn-Ni ordering Li 2 Mn 3 NiO 8 Ordered spinel, P Mn, Ni ordering or disordered at high temp over long time

10 In-operando battery cell for synchrotron studies at SNBL

11 Li 2 Mn 3 NiO 8 In-operando synchrotron experiments

12 Li 2 Mn 3 NiO 8 In-operando synchrotron experiments

13 Li 2 Mn 3 NiO 8 In-situ PXRD and XANES measurements Reduced d 8 octahedral d 7 Jahn Teller deformed Ni 2+ Ni 3+ Ni 4+ XANES: shift in edge position EXAFS: change 1. coordination sphere Oxidized d 6

14 Cycling Discharge capacity versus cycle number for "type B" cathodes prepared from LiMn1.5Ni0.5O4 powders. Discharge rates 15 ma/g (approximately 0.1 C); potential window V. And Galvanostatic charge and discharge curves We report the highest recorded specific capacity for the ordered phase, currently with submicron size particles as achieved by heat treatment at 900 C for 10 h followed by 700 C for another 10 h.

15 The motion Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 or Li 2 Mn 3 NiO 8? MoO 3

16 TEM and SAED on MoO 3 nanobelt Nice belts with well defined reflections in one direction

17 TEM and SAED on MoO 3 nanobelt Nice belts with well defined reflections in one direction Structural differences at nanoscale MoO 3 nanobelts vs bulk

18 Structural differences at nanoscale Stacking faults

19 High capacity cathode materials: Bulk and nanobelt MoO 3 Commercial state-of-the art cathode material LiFePO 4 /LiCoO 2 spinel, Must solve stability issue: degradation mechanism

20 Li insertion process for MoO 3 Computational modeling: Li Li MoO 3 Li 0.25 MoO 3 Li 1.75 MoO 3 In-situ diffraction: Rapid «amorphization» (loss of diffraction peaks)

21 α-moo 3 as cathode material N-doped α-moo 3 nanobelts gives the highest capacity to date α-moo 3 nanobelts are difficult to study because of preferred orientation Using bulk α-moo 3 as a model material for in situ diffraction studies Wang et. al. Vol. 3, is. 5, pg , Adv. Energy Mater. 2012

22 Prist. MoO 3 Phase transformation Galvanostatic cycling Li 1.4 MoO 3 Li x MoO 3 Pristine MoO 3 Li 1.4 MoO 3 Li x MoO 3 Li 1.4 MoO 3 Li 1.4 MoO 3

23 Li 0.2 MoO 3 Li 1.4MoO 3 α-moo 3 Layer expansion and contraction during lithiation

24 The motion Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 or Li 2 Mn 3 NiO 8? MoO 3 Preussian blue Na x Mn[Fe(CN) 6 ] y

25 Combined XRD and XAS analysis Follow Oxidation State Identify Phases

26 Na (de)insertion mechanism in Na x Mn[Fe(CN) 6 ] y charge discharge

27 The motion Li 2 (Mn 0.75 Ni 0.25 ) 4 O 8 or Li 2 Mn 3 NiO 8? MoO 3 Preussian blue Na x Mn[Fe(CN) 6 ] y Thin and solid

28 3D all-solid-state Li-ion batteries Solid state Li-ion batteries Safter, more environment friendly Low Li + conductivity Thin film electrolytes Compensate the low conductivity Facilitate architecture design 3-dimentional (3D) structure Desired power density Require suitibable thin film deposition technology Advanced Energy Materials 2011, 1, Adv. Funct. Mater. 2008, 18, 1057.

29 Cathode materials V 2 O 5 E. Østreng,, H. Fjellvåg, J. Mater. Chem. A, 2 (2014) FePO 4 K.B. Gandrud,, H. Fjellvåg, J. Mater. Chem A. 1 (2013) 9054

30 Conductivity measurements Cross-plane In-plane σ cross = L R A = d film R A electrode σ in = L R A = D electrode R (d film L) More practical interests Challenges: short-circuiting Difficult to carry out Circumvent the short-circuitings Significant resistance More sensitive to parasitics

31 Conductivity measurements Cross-plane In-plane σ cross = L R A = d film R A electrode σ in = L R A = D electrode R (d film L) More practical interests Challenges: short-circuiting Difficult to carry out Circumvent the short-circuitings Significant resistance More sensitive to parasitics

32 Conductivity of LiAlO 2 films T ( C) In-plane In-plane T ( C) cross-plane (Scm -1 ) nm (Scm -1 ) nm 160 nm E Solid: cooling Open: heating /T (K -1 ) 160 nm Solid: cooling Open: heating /T (K -1 ) E2 Thermally activated ionic characteristics Arrhenius relation: σ = σ 0 T exp( E a kt ) Larger thickness-dependence for in-plane method: surface, interface room temperature: ~ 10-9 Scm -1

33 T ( C) Conductivity of LiAlO 2 films (Scm -1 ) Open: in-plane Solid: cross-plane with decreasing T 160 nm /T (K -1 ) 235 nm 160 nm in 160 nm c E4 Single-crystalline 160 nm c E7 235 nm in γ-lialo2 235 E7 Inc Polycrystalline 237 -Cross Materials σ RT (S cm -1 ) E a (ev) Ref. LiAlO * ALD LiAlO 2 film on quartz substrate Quenched glass 0.6Li 2 O 0.4Al 2 O * 0.7Li 2 O 0.3Al 2 O 3 ALD LiAlO 2 films, sapphire and Ti substrates ~ * 1.14(1) (2) 0.73(1) 0.72(2) 0.76(1) 0.83 (1) 0.81 (extrinsic) 1.3 (intrinsic) * * Room temperature conductivity was rarely reported ~ ~0.8 Disordered amorphous/glassy Li x AlO y higher conductivity Improved conductivity can be expected with increasing Li content 2 4 This work 1. The Journal of Physical Chemistry C 2012, 116, J. Am. Ceram. Soc. 1984, 67, J. Chem. Mater. 2014, 26, J. Appl. Phys. 1980, 51,

34 Li x TaO y with Li content variation T ( C) T ( C) In-plane Cross-plane Increasing Li content x from 0.32 to 0.98 results in improved conductivity. (Scm -1 ) X /T (K -1 ) X /T (K -1 ) Compatible in-plane and cross-plane conductivities with acceptable deviations (< 1 order of magnitude). The film with highest Li content does not show a pronounced conductivity enhancement, probably due to the H/C surface enrichment. Li 0.32 TaO Li 0.51 TaO Li 0.98 TaO Li 1.73 TaO 3.73+

35 TiO 2 on structured surface TiO 2 coated

36 TiO 2 on structured surface Carbon structured surface TiO 2 coated

37 Acknowledgements Helmer Fjellvåg Mari Alnes Matti Putkonen Titta Aaltonen Ville Miikkulainen Knut B Gandrud Erik Østreng Anders Pettersen Amund Ruud Annina Moser Yang Hu Jonas Sottmann Ponniah Vajeeston Pushpaka Samarasingha Martin Sunding Anna Magraso Alexander Azarov Timo Sajavaara Leila Costelle Niels H. Andersen BALDUR COATINGS AS

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39 ALD reaction chambers Powder Nanocubes of Co 3 O 4.

40 ALD reaction chambers powder - mini 2 powder cells: Small = 1.5 ml Large = ca. 30 ml

41 ALD reaction chambers powder - maxi 500 ml

42 Li-battery Discharge Cathode Electrolyte Charge Anode

43 3D Batteries: Power and Energy 50 nm LiCoO 2 on 80 μm long pillars 1.3 μm in diameter, 1.3 μm distance between pillars mah/cm 2 x mah/cm 2 Bonus: Enhanced kinetics! Got both good power and energy density! Pillar lenght

44 Utstyr og brukere Reactors for coatings & thin films Atomic Layer Deposition Home made reactor Hybrid Closed/flow type reactor TSF 500 (BENEQ) Flow type reactor

45 Coating of powder Filter Nanocubes of Co 3 O 4.

46 ALD ALD Non-ALD ALD advantages: -Low processtemperature ( o C) -Confromal coverage, 3D -Easily scalable ALD

47 NAFUMA V Z ( ) V 0.29 V ImZ ( ) -3x10 9-2x10 9-1x10 9 T ( C) V 0 0 1x10 9 2x10 9 3x10 9 ReZ ( ) 0.01 V C V Z ( ) 3 Nov Electrochim. Acta 2015, 153, J. Mater. Chem. A 2014, 2,

48 Automated sample changer battery cycling, diffraction and XAS