Molecular dynamics studies of poly(ethylene oxide) based electrolytes - Revision history

Alvo at 04:45, 25 August 2007

2007-08-25T04:45:28Z

← Older revision		Revision as of 07:45, 25 August 2007
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	The work is done in close collaboration with [http://www.mkem.uu.se/Forskning/Struktur/Angstom_Adv_Battery/polymer_simulations/index.shtm Department of Materials Chemistry in Uppsala University]		The work is done in close collaboration with [http://www.mkem.uu.se/Forskning/Struktur/Angstom_Adv_Battery/polymer_simulations/index.shtm Department of Materials Chemistry in Uppsala University]

	==[[Our_publications#Polymer_electrolytes\|Publications]]		==[[Our_publications#Polymer_electrolytes\|Publications]]==

Alvo at 04:45, 25 August 2007

2007-08-25T04:45:08Z

← Older revision		Revision as of 07:45, 25 August 2007
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	The work is done in close collaboration with [http://www.mkem.uu.se/Forskning/Struktur/Angstom_Adv_Battery/polymer_simulations/index.shtm Department of Materials Chemistry in Uppsala University]		The work is done in close collaboration with [http://www.mkem.uu.se/Forskning/Struktur/Angstom_Adv_Battery/polymer_simulations/index.shtm Department of Materials Chemistry in Uppsala University]

			==[[Our_publications#Polymer_electrolytes\|Publications]]

Alvo at 04:43, 25 August 2007

2007-08-25T04:43:38Z

← Older revision		Revision as of 07:43, 25 August 2007
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	==People==		==People==
	[[User:Alvo\|Alvo Aabloo]]		[[User:Alvo\|Alvo Aabloo]]

	[[User:Heiki\|Heiki Kasemagi]]		[[User:Heiki\|Heiki Kasemagi]]

	[[User:Anti\|Anti Liivat]]		[[User:Anti\|Anti Liivat]]

	[[User:Daniel\|Daniel Brandell]]		[[User:Daniel\|Daniel Brandell]]
	[[User:~~Jaanus~~\|Jaanus Karo]]
			[[User:Jaanuska\|Jaanus Karo]]

			The work is done in close collaboration with [http://www.mkem.uu.se/Forskning/Struktur/Angstom_Adv_Battery/polymer_simulations/index.shtm Department of Materials Chemistry in Uppsala University]

Alvo at 04:39, 25 August 2007

2007-08-25T04:39:39Z

← Older revision		Revision as of 07:39, 25 August 2007
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	Inorganic nano-particles can both prevent PEO from crystallisation ("nano-plasticising"), but also modify the local structure and dynamics of the surrounding polymer and the solvated ions. Our group has investigated a number of PEO systems with Al<sub>2</sub>O<sub>3</sub> nano-particles additives with MD techniques.		Inorganic nano-particles can both prevent PEO from crystallisation ("nano-plasticising"), but also modify the local structure and dynamics of the surrounding polymer and the solvated ions. Our group has investigated a number of PEO systems with Al<sub>2</sub>O<sub>3</sub> nano-particles additives with MD techniques.

	==~~Contact~~==		==People==
	[[User:Alvo\|Alvo Aabloo]]		[[User:Alvo\|Alvo Aabloo]]
			[[User:Heiki\|Heiki Kasemagi]]
			[[User:Anti\|Anti Liivat]]
			[[User:Daniel\|Daniel Brandell]]
			[[User:Jaanus\|Jaanus Karo]]

Alvo: /* Crystalline polymer electrolytes */

2007-02-09T15:04:35Z

Crystalline polymer electrolytes

← Older revision		Revision as of 18:04, 9 February 2007
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	===Crystalline polymer electrolytes===		===Crystalline polymer electrolytes===

			[[Image:LiPF6PEO6 small.png]]

	Crystalline phases of polymer electrolytes were long regarded as insulators. This view has been overturned to some extent during recent years by the demonstration of ionic conductivity in the complexes LiXF<sub>6</sub>PEO<sub>6</sub> for X = P, As or Sb. Although the conductivity is still relatively low in these materials, they nevertheless show ca. ten times higher ionic conductivity than their amorphous counterparts. The LiXF<sub>6</sub>PEO<sub>6</sub> complexes also display very fascinating structures – the materials are composed of coaxial hemi-helices of PEO, which pairwise form cylindrical channels containing the lithium ions coordinated to ether-oxygen chains; the anions lie outside the hemi-helical pairs, with no directstructural interaction with the lithium ions (see Fig. 1).		Crystalline phases of polymer electrolytes were long regarded as insulators. This view has been overturned to some extent during recent years by the demonstration of ionic conductivity in the complexes LiXF<sub>6</sub>PEO<sub>6</sub> for X = P, As or Sb. Although the conductivity is still relatively low in these materials, they nevertheless show ca. ten times higher ionic conductivity than their amorphous counterparts. The LiXF<sub>6</sub>PEO<sub>6</sub> complexes also display very fascinating structures – the materials are composed of coaxial hemi-helices of PEO, which pairwise form cylindrical channels containing the lithium ions coordinated to ether-oxygen chains; the anions lie outside the hemi-helical pairs, with no directstructural interaction with the lithium ions (see Fig. 1).

Alvo: /* Nano-particles in polymer electrolytes */

2007-02-09T15:03:41Z

Nano-particles in polymer electrolytes

← Older revision		Revision as of 18:03, 9 February 2007
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	==Nano-particles in polymer electrolytes==		==Nano-particles in polymer electrolytes==
			[[Image:Nanoparticle small.png]]

	Inorganic nano-particles can both prevent PEO from crystallisation ("nano-plasticising"), but also modify the local structure and dynamics of the surrounding polymer and the solvated ions. Our group has investigated a number of PEO systems with Al<sub>2</sub>O<sub>3</sub> nano-particles additives with MD techniques.		Inorganic nano-particles can both prevent PEO from crystallisation ("nano-plasticising"), but also modify the local structure and dynamics of the surrounding polymer and the solvated ions. Our group has investigated a number of PEO systems with Al<sub>2</sub>O<sub>3</sub> nano-particles additives with MD techniques.

Alvo: /* Crystalline polymer electrolytes */

2007-02-09T15:03:30Z

Crystalline polymer electrolytes

← Older revision		Revision as of 18:03, 9 February 2007
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	===Crystalline polymer electrolytes===		===Crystalline polymer electrolytes===

	~~[[Image:Nanoparticle small.png]]~~

	Crystalline phases of polymer electrolytes were long regarded as insulators. This view has been overturned to some extent during recent years by the demonstration of ionic conductivity in the complexes LiXF<sub>6</sub>PEO<sub>6</sub> for X = P, As or Sb. Although the conductivity is still relatively low in these materials, they nevertheless show ca. ten times higher ionic conductivity than their amorphous counterparts. The LiXF<sub>6</sub>PEO<sub>6</sub> complexes also display very fascinating structures – the materials are composed of coaxial hemi-helices of PEO, which pairwise form cylindrical channels containing the lithium ions coordinated to ether-oxygen chains; the anions lie outside the hemi-helical pairs, with no directstructural interaction with the lithium ions (see Fig. 1).		Crystalline phases of polymer electrolytes were long regarded as insulators. This view has been overturned to some extent during recent years by the demonstration of ionic conductivity in the complexes LiXF<sub>6</sub>PEO<sub>6</sub> for X = P, As or Sb. Although the conductivity is still relatively low in these materials, they nevertheless show ca. ten times higher ionic conductivity than their amorphous counterparts. The LiXF<sub>6</sub>PEO<sub>6</sub> complexes also display very fascinating structures – the materials are composed of coaxial hemi-helices of PEO, which pairwise form cylindrical channels containing the lithium ions coordinated to ether-oxygen chains; the anions lie outside the hemi-helical pairs, with no directstructural interaction with the lithium ions (see Fig. 1).

Alvo: /* Crystalline polymer electrolytes */

2007-02-09T15:02:58Z

Crystalline polymer electrolytes

← Older revision		Revision as of 18:02, 9 February 2007
Line 11:		Line 11:

	===Crystalline polymer electrolytes===		===Crystalline polymer electrolytes===

			[[Image:Nanoparticle small.png]]

	Crystalline phases of polymer electrolytes were long regarded as insulators. This view has been overturned to some extent during recent years by the demonstration of ionic conductivity in the complexes LiXF<sub>6</sub>PEO<sub>6</sub> for X = P, As or Sb. Although the conductivity is still relatively low in these materials, they nevertheless show ca. ten times higher ionic conductivity than their amorphous counterparts. The LiXF<sub>6</sub>PEO<sub>6</sub> complexes also display very fascinating structures – the materials are composed of coaxial hemi-helices of PEO, which pairwise form cylindrical channels containing the lithium ions coordinated to ether-oxygen chains; the anions lie outside the hemi-helical pairs, with no directstructural interaction with the lithium ions (see Fig. 1).		Crystalline phases of polymer electrolytes were long regarded as insulators. This view has been overturned to some extent during recent years by the demonstration of ionic conductivity in the complexes LiXF<sub>6</sub>PEO<sub>6</sub> for X = P, As or Sb. Although the conductivity is still relatively low in these materials, they nevertheless show ca. ten times higher ionic conductivity than their amorphous counterparts. The LiXF<sub>6</sub>PEO<sub>6</sub> complexes also display very fascinating structures – the materials are composed of coaxial hemi-helices of PEO, which pairwise form cylindrical channels containing the lithium ions coordinated to ether-oxygen chains; the anions lie outside the hemi-helical pairs, with no directstructural interaction with the lithium ions (see Fig. 1).

Alvo: /* Introduction */

2007-02-09T15:02:10Z

Introduction

← Older revision		Revision as of 18:02, 9 February 2007
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	Solid electrolytes for the Lithium-Ion Polymer Battery can be produced by mixing a lithium salt, typically LiPF<sub>6</sub> or LiBF<sub>4</sub>, into poly(ethylene oxide) (PEO), -(CH<sub>2</sub>CH<sub>2</sub>O)n-. However, such electrolytes only exhibit adequate ionic conductivity (>10<sup>-4</sup> S/cm) at temperatures above 70°C, where the polymer becomes amorphous. The conventional wisdom has been that the high degree of local order (“crystallinity”) is the reason for the poor ionic conductivity at ambient temperatures. Much attention has therefore been devoted to the task of increasing the amorphous content of the PEO electrolyte at ambient temperatures.		Solid electrolytes for the Lithium-Ion Polymer Battery can be produced by mixing a lithium salt, typically LiPF<sub>6</sub> or LiBF<sub>4</sub>, into poly(ethylene oxide) (PEO), -(CH<sub>2</sub>CH<sub>2</sub>O)n-. However, such electrolytes only exhibit adequate ionic conductivity (>10<sup>-4</sup> S/cm) at temperatures above 70°C, where the polymer becomes amorphous. The conventional wisdom has been that the high degree of local order (“crystallinity”) is the reason for the poor ionic conductivity at ambient temperatures. Much attention has therefore been devoted to the task of increasing the amorphous content of the PEO electrolyte at ambient temperatures.

			[[Image:PEO small.png]]

	===Methodology - Molecular Dynamics simulations===		===Methodology - Molecular Dynamics simulations===

Alvo: /* Contact */

2007-02-09T14:59:36Z

Contact

← Older revision		Revision as of 17:59, 9 February 2007
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	==Contact==		==Contact==
	[[User:Alvo\|\|Alvo Aabloo]]		[[User:Alvo\|Alvo Aabloo]]

← Older revision		Revision as of 07:43, 25 August 2007
Line 29:		Line 29:
	==People==		==People==
	[[User:Alvo\|Alvo Aabloo]]		[[User:Alvo\|Alvo Aabloo]]

	[[User:Heiki\|Heiki Kasemagi]]		[[User:Heiki\|Heiki Kasemagi]]

	[[User:Anti\|Anti Liivat]]		[[User:Anti\|Anti Liivat]]

	[[User:Daniel\|Daniel Brandell]]		[[User:Daniel\|Daniel Brandell]]
	[[User:~~Jaanus~~\|Jaanus Karo]]
			[[User:Jaanuska\|Jaanus Karo]]

			The work is done in close collaboration with [http://www.mkem.uu.se/Forskning/Struktur/Angstom_Adv_Battery/polymer_simulations/index.shtm Department of Materials Chemistry in Uppsala University]