Plug-in 2008 Battery Workshop

Moderator: Haresh Kamath, EPRI 

Fritz Kalhammer

Background: 20 years at EPRI, now consultant and focuses on battery and fuel-cell technology for electric an hybrid vehicles

• Opening quote: "The battery is the key to commercialization and eventual success of the electric plug-in hybrid vehicle."
• PHEV performance: all need 50 to 100 kW power, 500 W/kg power density, Li Ion meet this
  • 10 miles, 4-4.5 kWh
  • 20 709
  • 40 14-18
  • Small EV: 20-25
• Needs calendar life of 10-15 years
• Cycle life of 2,500 to 3,000 deep cycles (95% to 20% to 95% SOC)
• Some battery technologies meet this requirements
• Li Ion calendar life depends on temperature. 40 degC can last 10 years, at 60 degC lasts only 3 years
• A123 Iron phosphate can go to 7000 cycles
• EnerDel Li Titanate cycle life goes to 2,500 with no capacity loss and should go to 10,000 cycles
• Li Ion batteries can now be made sufficiently safe for the requirements of the automobile industry
• Small EV NPV fuel cost savings $7,412, li Io Battery cost $9,000
• Mass-produced Li Ion PHEV batteries should cos less than PHEV lifetime fuel cost savings
• No material limitations, but lithium production will need to be ramped up
• Greenfield factory for batteries can be completed in about 2 years and can create about 500k battery packs per year
• No big manufacturers are developing full performance EV batteries with 100 to 150 mile range, only small manufacturers that have just small production capacity are addressing this market

Tien Duong

Team Lead at US DOE for Vehicle Technology program

• US consumers would like an EV with 300 to 400 mile range but this is very costly to design
• Many performance requirements have been met for Li Ion batteries, but cost is still 2 times too high
• Cost of Li-ion should hit $500/kWh by 2012
• Iron Phosphate LiFePO4 is safe, but has low energy and cycle life is unknown
• DOE moving focus from high-power HEV systems to high-energy PHEV and EV

Ahmad Pesaran

Principle Engineer, National Renewable Energy Laboratory, focuses on thermal analysis and testing

• USABC/FreedomCar PHEV Battery Requirements for 40 miles
  
  • Power: 46/38 kW
  • Energy: 11.6 kWh
  • Internal battery temp: 52 degC (125 degF) 100% power, 0 degC 50% power
• If batteries are at different temperatures, they age differently and then will become out of balance
• Having 3 separate batteries in ambient air versus 1 large cell will give more uniform temperature
• Also better to have terminals on both sides, rather than on the same side of the cell
• Testing real PHEV around Colorado, switching to A123 soon
• Probably most PHEV applications will use liquid cooling of batteries, but might go back to air cooling at some point because it is less complex

Loic Gaillac

SCE 

• SCE is one of the largest electric utilisins serving 5 millions custoemrs, larges EV fleets in the nation 260EVs - 16 million miles)
• Has EV Tech Center (EVTC) in Pomona testing SAFT li-ion pack, 17 cells providing 15.5 kWh
• Test profile replicates urban driving conditions likely to be most demanding - delivery van
• Deplete 100% to 25%, sustain at 25% then charge at C/2 - 2.6 hour drive, 50 miles,
• Cycle lasts 6 hours, 4 cycles per day, liquid cooled to 25 degC
• Every 200 cycles (about every 50 days) does a reference performance test (RPT): a C/1 test, C/3, peak power, 
• As of July 2008, went through 3300 which took 32 months and is about 165k miles. Battery has only 14% capacity and power degradation. 4 years calendar life and 62 MWh throughput
• Past 800 cycles, battery degradation has been going down fairly linearly
• Expect to reach 4,000 cycle or 200,000 miles for these SAFT Li-ion batteries
• Future will look at A123, Altairnano, JCS, other Li-ion chemistries
• Also looking at battery residential storage capability

Andy Burke

UCD, Institute of Transportation Studies

• Studying emerging battery technologies
• If paying for the battery over the life of the battery, put the biggest battery into the car

Haresh Kamath

EPRI

Topic: EVs - Why Is it Different This Time?

• Gas price going up
• Battery cost going down, Li-ion small cells now $500/kWh. However larger cells are still about $1,000/kWh
• Cell problems
  • Cell selection
  • Battery management system
  • Thermal management
  • Understanding performance over life
  • Safety
• Li-ion is presently the battery of choice
• Large format cell development is crucial for bringing down costs
• Battery integration issues a neglected area of development

Michael Andrew

Johnson Controls, SAFT, Manager Hybrid Battery Development

• By 2020 expects 6% of the vehicle market to be electrified in some way
• Consistent long-term government policy will be paramount to ensure the capital investments necessary for a sustainable electrified powertrain industry
• Lead-acid batteries recycle 97% of the lead
• Li-ion battery recycling faces challenges getting the infrastructure up but the fundamental technology is there
• V2G could be one-way to the battery and instruct the battery when to charge. This would be much simplier than 2 way V2G flow. This could cause the cost of ownership of PHEV to actually go down over time rather than up

Veselin Manev

Altairnano

• Their batteries use titanate that replaces graphite
• Can be discharged or charged at 10C rate and retain 90% capacity. Can continually do this without degradation
• At 55 degC can do 4,000 cycles at 1C charge and discharge and retain 85% of initial capacity
• Larger cell, 50Ah cells cycling at 25 degC retains 95% capacity after 4,000 cycles 
• Capacity fade in 11Ah is negligible after 120 days at 40 degC, at 55 degC is about 1%
• Calculations suggest that after 25 years, fade at 25 degC will be below 1% and at 55 degC below 6%
• Self discharge is about 3% per year
• 2MW battery for electricity regulation with continuous 4C rate of charge and discharge. Efficiency was between 91% to 97% (to 50% SOC). 

Andy Chu

A123 Systems

• Nano-phosphate technology
• Leading producer of high-powered Li-ion batteries
• Power tools number one user of high-powered Li-ion batteries, also looking at power regulation and EVs
• A123 safer from thermal runaway
• For 1C 100% DOD cycling can do 10,000 cycles and still be above 75% energy capacity and with very little impedance rise so it has basically the same power but just less energy. This also means heat at the end-of-life is similar to heat generation at the start.

Gitanjali DasGupta

Electrovaya, Manager Electric Vehicle Division

• Public company in Toronto
• Advantages: Focuses on high-energy, large format and integrated BMS
• Getting 170 Wh/kg but aiming for 275 Wh/kg
• Only prismatic, which has intrinsic safety protection
• Standard cell is 1.5kWh
• Cycle life?
• Low speed vehicles: maya-300, launches this fall
• Partner with Phoenix MotorCars

Mohammed Alamgir

Compact Power, subsidiary of LG Chem

• Focuses on large format, automotive batteries
• Safety and manufacturing advantages
• 150 wWh/kg
• Calendar life over 20 years,
• Cycles 3,000 or 150,000 miles
• Prismatic cells are better at heat dissipation is better than cylindrical cells
• Has a very good SOC calculation method