Chemistry Solid State Cells
Solid State Cell Chemistries and Designs
Sehee Lee Department of Mechanical Engineering University of Colorado at Boulder
Crash‐Safe Energy Storage Systems For Electric Vehicles Workshop Denver, CO November 12 & 13, 2012 1
Outline
History Basic theory (solid state electrolytes) SOA solid state batteries All-solid-state lithium secondary batteries Solid Power, Inc.
2
Why solid state battery?
?
Advantages No flammable liquid electrolyte Ultimate safety No thermal runaway High energy density No safety devices required Excellent cycling stability Excellent shelf life
3
Disadvantages Slower kinetics due to • Low ionic conductivity • High interfacial resistance • Poor interfacial contact
General Solid State Battery Construction
Two electrodes are separated by solid state electrolyte layer – Electrolyte has high ionic conductivity and is electronically insulating Composite electrodes – Incorporate solid electrolyte into composite for fast ion transport – Incorporate conductive additive into composite for fast electron transport
Solid Electrolyte Lithium Metal Anode Cathode Li anode SSE Cathode Conductive Additive Active Material
4
History
1839 (Michael Faraday) The first solid state electrolyte, PbF2 at high temperature
1884 (Warburg) Demonstrated Na+ conduction in glass 1888 (Warburg & Tegetmeier) The first measurement of transference number ~ 1900 (Walther Nernst) Discovery of “ Nernst glower” – a ceramic rod was heated to incandescence → SOFC (solid oxide fuel cell), oxygen gas sensor
1914 1966
(Tubandt & Lorenz) High Ag+ conductivity of AgI at 150oC (Ag/AgI/Ag) (Kummer & Webber @ Ford Motor) Developed Na/S battery by using Na+ conductor “sodium beta alumina (β-Al2O3)”. 1973 (P. V. Wright) 1978 (M. B. Armand, J. M. Chabagno, M. Duclot) First polymer electrolyte
5
Conduction Mechanisms
Vacancy conduction Interstitial conduction
Schottky defect
(a cation & anion vacancy pair)
T ↑ → defect ↑ → conductivity
Sehee Lee Department of Mechanical Engineering University of Colorado at Boulder
Crash‐Safe Energy Storage Systems For Electric Vehicles Workshop Denver, CO November 12 & 13, 2012 1
Outline
History Basic theory (solid state electrolytes) SOA solid state batteries All-solid-state lithium secondary batteries Solid Power, Inc.
2
Why solid state battery?
?
Advantages No flammable liquid electrolyte Ultimate safety No thermal runaway High energy density No safety devices required Excellent cycling stability Excellent shelf life
3
Disadvantages Slower kinetics due to • Low ionic conductivity • High interfacial resistance • Poor interfacial contact
General Solid State Battery Construction
Two electrodes are separated by solid state electrolyte layer – Electrolyte has high ionic conductivity and is electronically insulating Composite electrodes – Incorporate solid electrolyte into composite for fast ion transport – Incorporate conductive additive into composite for fast electron transport
Solid Electrolyte Lithium Metal Anode Cathode Li anode SSE Cathode Conductive Additive Active Material
4
History
1839 (Michael Faraday) The first solid state electrolyte, PbF2 at high temperature
1884 (Warburg) Demonstrated Na+ conduction in glass 1888 (Warburg & Tegetmeier) The first measurement of transference number ~ 1900 (Walther Nernst) Discovery of “ Nernst glower” – a ceramic rod was heated to incandescence → SOFC (solid oxide fuel cell), oxygen gas sensor
1914 1966
(Tubandt & Lorenz) High Ag+ conductivity of AgI at 150oC (Ag/AgI/Ag) (Kummer & Webber @ Ford Motor) Developed Na/S battery by using Na+ conductor “sodium beta alumina (β-Al2O3)”. 1973 (P. V. Wright) 1978 (M. B. Armand, J. M. Chabagno, M. Duclot) First polymer electrolyte
5
Conduction Mechanisms
Vacancy conduction Interstitial conduction
Schottky defect
(a cation & anion vacancy pair)
T ↑ → defect ↑ → conductivity