Large Format Lithium Power Cells for Demanding Hybrid Applications Adam J. Hunt Manager of Government Programs 2011 Joint Service Power Expo Power to Sustain Warfighter Dominance Myrtle Beach, SC May 4, 2011 1 NOVEMBER /// 2010
CONTENTS Ener1 Overview Negative Active Materials Comparison Lithium titanate vs. other common materials Lithium titanate characteristics EnerDel LTO Cell Performance Small cells Large cells Multiple cells in series Conclusions & Final Remarks 2
GLOBAL SUPPLY STRATEGY Total Employees: 750 (Excl. China/Think) Symbol/NASDAQ: HEV ENER1 / CORPORATE HQ / NYC, U.S. ENER1 EUROPE / SALES & MARKETING / Paris, France ENERDEL / Indianapolis, IN, U.S. ENERDEL / Noblesville, IN, U.S. ENERDEL / Mount Comfort, IN, U.S. ENERDEL / R&D CENTER / Japan ENER1 KOREA / Korea WANXIANG / SHANGHAI, CHINA THINK GLOBAL / Norway 3
U.S. FACILITIES Easily replicated production processes allow us to expand capacity and locate facilities in-country near clients facilities Ener1 Lithium Group Established in 1990 Delphi Lithium Group 1998 EnerDel 2004 Total Area: ~ 98,000 ft 2 Production & R&D of Lithium-Ion Cells for multiple applications Lease signed January 2010 Total Area: 400,000 ft 2 Production Lithium-Ion Cells for multiple applications Final Pack Assembly Operations Production Launch in May Made possible by $118.5 million in federal grant funding under the ARRA stimulus package Established in 2009 Floor Space -38,500 ft 2 BMS Engineering & Test 4
TOTAL SOLUTION PROVIDER FOR LI-ION BATTERY SYSTEM EnerDel battery system concept provides maximum flexibility to meet customer s requirement CELL Advanced Prismatic Design High Performance Li-Ion Cells EV System HEV System MODULE Easy Maintenance Module Concept Integrated Thermal Management Voltage & Temperature Monitoring High Speed Vehicle Communication SYSTEM Robust Battery System Integrated reuse design concept 5
NEGATIVE ACTIVE MATERIAL COMPARISON Graphite Most common active material for existing lithium ion cells Most energy density per volume Non-graphite carbon Less reaction with electrolyte than graphite Higher power than graphite Longer life than graphite Lithium Titanate (Li4Ti5O12) No reaction with electrolyte Less impedance Longer life Less Energy density 6
NEGATIVE ACTIVE MATERIAL COMPARISON Characteristic Graphite Carbon Lithium Titanate Long Life 3 2 1 Power 3 2 1 Energy 1 2 3 Low temperature 3 2 1 Safety 3 2 1 1 BEST 2 BETTER 3 - GOOD Lithium Titanate cell performance will be presented in this presentation 7
The Titanate Anode A very stable oxide best known for its safety and long cycle life Theoretical capacity of 165 mah/g is about half that of graphite (372 mah/g) It operates at 1.5V vs. Li which is above the voltage at which Li dendrites can occur Less than 0.2% volumetric change from fully discharged Li 4 Ti 5 O 12 to fully charged Li 7 Ti 5 O 12 titanate (for comparison, graphite is 9% and silicon is 300%) <J. Electrochem. Soc. 146(1999) 857> 8
LTO CHARACTERISTICS Advantages Zero strain material LTO Graphite ~ 0.02 % volume change ~ 9% volume change No lithium dendrites Less impedance than graphite High power Good low temperature performance Long life Safety Disadvantages Lower Energy Density Lower Voltage Intensity / Arb. unit (111) DOD 0% DOD 40% DOD 90% DOD 100% 10 20 30 40 50 60 70 80 2 Theta / degree (CuKa) Fig. XRD patterns of LTO material at different DOD Li 4 Ti 5 O 12 - spinel (LTO) Li 4 Ti 5 O 12 + xli + + xe - Li 4+x Ti 5 O 12 (311) (222) Cu, (400) (311) Cu (511) (333) (440) (531) Cu, (533) (622) (444) 9
LTO Anode The Li insertion in titanate occurs at ~1.5V, well above the voltage at which Li deposition occurs Stan Whittingham SUNY 10
THERMAL STABILITY OF LTO Scan range; 50 350 o C Scan rate: 10 o C/min LTO negative shows less heat generation than graphite negative 11
LTO HALF CELL RESULTS very flat charge or discharge curve very small irreversible capacity 12
LTO HALF CELL RESULTS discharge rate capability is exceptional excellent for power applications (this is equivalent to discharge rate capability in a full cell) 13
ENERDEL SMALL CELL DESIGN FOR LIGHT-DUTY VEHICLE APPLICATIONS DESCRIPTION SPECIFICATION Application Light-duty vehicle Nominal Capacity 1.8Ah 5Ah Max Voltage 2.8V Min voltage 1.5V Cell size 145 x 130 x 5 mm 200 x 111 x 5 mm Chemistry LTO/LMO 14
TEMPERATURE INCREASE AT HIGH POWER CYCLE 70 LTO/LMO 1.8Ah Cell 4.5 70 Graphite/LMO 1.8Ah Cell 6.0 65 60 Cell Temperature Voltage 4.0 65 60 5.5 5.0 Temperature / o C 55 50 45 40 3.5 3.0 2.5 2.0 Voltage / V Temperature / o C 55 50 45 40 4.5 4.0 3.5 3.0 2.5 Voltage / V 35 30 1.5 35 30 Cell Temperature Voltage 2.0 1.5 25 1.0 0 10 20 30 40 50 60 Time / Min 25 0 10 20 30 40 50 60 Time / Min 1.0 15
5 AH FULL CELL: HIGH TEMPERATURE CYCLING 2C cycling at 55 C excellent high temperature capacity retention 16
CYCLE LIFE 2.0 1.8 Discharge capacity / Ah 1.6 1.4 1.2 1.0 0.8 0.6 0.4 55 o C 5C charge 5C discharge 100% DOD 0.2 0.0 0 500 1000 1500 2000 2500 3000 Cycle Number No capacity loss under severe cycling conditions. 17
EXTREME ABUSE TEST, LTO CELLS Overcharge and nail penetration 6.0 210 5.0 Nail penetrates 180 4.0 150 Voltage (V) 3.0 2.0 1.0 Cell Voltage Cell Temperature 120 90 60 Temperature (C) 0.0 30 Room Temperature -1.0 0 0 2 4 6 8 10 12 14 16 18 Time (min) 18
HEV BATTERY PACK WITH ENERDEL LTO CELLS We can reduce the battery size by one-half compared to existing Ni-MH pack 19
LARGER SIZE LTO CELL DESCRIPTION SPECIFICATION Application Heavy-duty vehicle Nominal Capacity 9.5Ah Max Voltage 2.75V Min voltage 1.6V Cell size 172x 253 x 5.8 mm Chemistry LTO/Mixed Oxide Mixed oxide was used for the positive active materials instead of LMO 20
Voltage(V) Voltage_V DISCHARGE PROFILE 9.5AH CELL 3 2.4 2.5 2.2 2 1.5 1 Cycle 3_30C Cycle 803_26C 2 1.8 1.6 1.4 1C 3C 5C 10C 20C 25C 0.5 1.2 0 0 2 4 6 8 10 Discharge_Capacity(Ah) 1 0 2 4 6 8 10 12 Discharge capacity_ah Discharge profile comparison at 3 rd cycle and 803 rd cycle Rate Capability 21
CYCLE LIFE 9.5AH CELL Capacity loss is not observed through first 1000 cycles. 22
THERMAL TEST WITH 3 CELLS IN SERIES (30 C) 8 points of the cell temperature were measured Max 10 o C increase with 25C continuous discharge 23
NAIL PENETRATION (9.5AH CELL) 3mm diameter nail, penetrating with a rate of 80 mm/s No thermal event was observed. No explosion, no fire, no flame, no smoke. Irreversible cell damage. EUCAR /SAE J2464 hazard level = 2 Cell was not shorted right away. It took 1 hr for the cell voltage to reach 0V Positive terminal temperature reached 32 C 24
CONCLUSIONS SAFE LARGE FORMAT HIGH POWER LONG LIFE MECHANICALLY STABLE MADE IN THE UNITED STATES COMPATIBLE WITH EXISTING ENER1 MODULE STRUCTURE 25
ACKNOWLEDGEMENT Ener1 would like to thank the Department of Energy National Energy Technology Laboratory for funding under cooperative research agreement DE-FC26-08NT01929 and the U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) for Financial Support in the continued refinement and demonstration of the Titanate High-Power cells used for W56HZ-09-C-0681. 26
THANKS FOR YOUR ATTENTION! PLEASE VISIT US IN BOOTH #110 ADAM J. HUNT MANAGER OF GOVERNMENT PROGRAMS (317)585-3464 AHUNT@ENER1.COM WWW.ENER1.COM 27