Lithium Ion Batteries - for vehicles and other applications

Transcription

1 Lithium Ion Batteries - for vehicles and other applications Tekes Kai Vuorilehto / European Batteries

2 What do we need? High energy (Wh/kg) driving a car for 5 hours High power (W/kg) accelerating Toyota Prius for 5 seconds These are hard to achieve simultaneously so we need basic knowledge about batteries

3 Basic division Primary batteries (non-rechargeable) hardly practical for vehicles etc. in Finnish paristo Secondary batteries (rechargeable) in Finnish akku What is the scientific difference?

4 Cell constructions Button cells (small) Cylindrical cells (medium size) Bobbin or Swiss roll Prismatic cells (large) Stacked Elliptical Special geometries (eg. for satellites)

5 Button cell

6 Cylindrical cell - bobbin

7 Cylindrical cell swiss roll

8 Prismatic cells

9 Special design Nickel-hydrogen battery for Iridium satellites

10 Secondary batteries - chemistries Pb-PbO 2 NiOOH-Cd NiOOH-MH Li-ion C-CoO 2 C-Mn 2 O 4 C-FePO 4 Ti 5 O 12 -Mn 2 O 4

11 Secondary batteries - energy Pb-PbO 2 35 Wh/kg NiOOH-Cd 35 Wh/kg NiOOH-MH 75 Wh/kg Li-ion (C-CoO 2 ) Wh/kg Li-ion (C-Mn 2 O 4 ) Wh/kg Li-ion (C-FePO 4 ) Wh/kg

12 Principle of the lithium-ion battery

13 Principle of the lithium-ion battery NOT a lithium battery, as there is no metallic lithium Metallic lithium could form dendrites and cause short circuit Lithium ions are intercalated in host lattices (graphite etc.) Each ion has its "own home"

14 Negative electrodes (anodes) Graphite standard material high voltage, 3.6V with CoO 2 Titanate extremely stable fast charge and discharge low voltage, about 2V with CoO 2» (promising for hybrid use?)

15 Positive electrodes (cathodes) Cobalt oxide standard material, 3.6V expensive, toxic and dangerous Manganese oxide cheap, slightly soluble, 3.7V Iron phosphate extremely stable, fast charge and discharge lower voltage 3.2V

16 Electrolytes Ethylene carbonate & its derivatives as solvent Lithium hexafluorophosphate as salt Hardly any alternatives Lithium polymer batteries can use polymer electrolytes

17 Structure It must be easy to fabricate It must be robust It must keep stack pressure It must let heat to come out» (important for hybrid use!) Small volume is advantageus

18 Cylindrical

19 Elliptical

20 Stacked

21 Players on the field Company Products, chemistries A123 medium iron phosphate, large format in R&D, USA & China Kookam large cobalt oxide cells in R&D, Korea Valence medium iron phosphate cylindrical cells, USA & China Saft large and medium, cobalt oxide, & iron phosphate, France Samsung large iron phosphate (Power), in R&D, Korea LG large and medium manganese oxide in R&D, Korea International Battery large iron phosphate, USA K2 medium iron phosphate, USA & China European Batteries/K2 large iron phosphate, together with K2, Finland Small cell producers: Sanyo, Sony, Panasonic,

22 Connecting cells Parallel internal resistance should be similar not a big problem Series capacity should be very similar overcharge & overdischarge is problematic Parallel & Series first parallel, then series

23 Battery management system controlling voltage in cell level avoid overcharge & overdischarge controlling temperature in cell level stop the system in time calculating state of charge compensating differences in state of charge

24 Safety Chemistry Production technology Battery management system Fuses, pressure valves etc.

25 Citius, altius, fortius Safer Cheaper Smaller

26 A Finnish company, founded 2008, owned by its investors, FEVT and key personnel Company develops, manufactures and sells advanced large-scale (>40 Ah) rechargeable lithium-ion batteries and battery systems Office in Espoo and R&D site in Varkaus The company is starting to produce large-scale lithium-ion batteries in Varkaus Factory design started January 2008 Construction work started September 2008 Manufacturing facility in full production Autumn 2009 Facility: m 2 Capacity: Ah/month 32 MWh/month

27 Company has 4.5 million euro share capital or commitments for shares The ownership structure will develop, when new investors come in The company s American partner K2 has an option to become a shareholder with 10% ownership. The option is valid through year Note: Eboy owns approx 11% of common shares of K2

28 LFP Our technology Choice In our R&D process For anode material Source: Monitor Consulting, 2008

29 400 Energy Density vs Specific Energy * Energy Density, Whr/l Pb Acid NiCd Li-Polymer LiFePO4 NiMH Li Ion: LiCoO Source: Company and K2 Specific Energy, Wh/kg

30 Lead Acid NiCd NiMH Li ion LiCoO2 Li ion LiFePO4 Battery/pack specific energy, Wh/kg Cycles Charge time, hr Self discharge/mo, % Avg operating Voltage Relative battery/pack cost 1X 3-4X 3-4X 4-5X 3-4X Relative safety Relative environmental Source: K2

31 Battery design capabilities; the jointly developed large-format prismatic lithium-ion battery design is costefficient, environmentally friendly and light weight with high energy contents. Material science: the advanced formulation and coating techniques obtained from K2. Efficient production technology: low raw material consumption and fast production Vertical integration from cell chemistry to system design: the close co-operation with FEVT we can address design requirements at the chemistry, battery or battery system levels

32 Other energy solutions