Electric Propulsion Experiences with a Honda Insight

1. Electric Propulsion Experiences with a Honda Insight Gary Graunke Oregon Electric Vehicle Association (Oregon chapter of the Electric Auto Association) June 25, 2010

2. Agenda Why the interest in electric cars now? Battery progress, fuel costs/efficiency, renewables for fuel My Conversion Experience Selecting a vehicle to convert Planning Components Mechanical Batteries, charging, and battery management Operational, maintenance experience Summary Questions and Answers

3. Why I Converted a Car Interest in fuel cells GM visited my high school in 1966: “fuel cell cars are just around the corner” Energy crisis of the 1970’s Oil induced inflation: I wrote a program to report status of investigations into violations Nixon’s wage-price freeze Oil price went from $2/bbl to $20 US oil production peaked in 1970—we lost control of price of oil Fuel rationing: we stood in line for 4 hours to get 10 gals on odd/even days The citicar was the only afforable EV—the rest cost more than my house Failed CARB EV mandate of the 1990’s But I rented a Honda EV Plus 3 times, EV1 once Automakers could not see profitable business plan—crushed cars Late wife’s cancer diagnosis reminded me that I’m getting old

4. Progress in Li Batteries In the last 20 years, batteries are 18X more KWH/kg, KWH/$ Doubles about every 5 years We expect 2 more generations before slowing improvement US ABC goal is $200/KWH Current cost is $500/KWH Nissan cost will be $375 in 2012 production $32700 car goes 100 mi on charge Lifetime cost more important than initial cost My LiFePO A123 cells were $1500/KWH, but expect 3500 cycles Must factor in number of charge cycles Li affected by stored temperature of batteries

5. Global Energy Potential Source: Steve Heckeroth, American Solar Energy Society Area needed to power U.S. electrical needs: 104 Square miles in SW Nevada Slides: Impacts of Plug-in-Hybrid Vehicles on Regional U.S. Power, Michael Kintner-Meyer, Pacific Northwest National Laboratory, www.plugincenter.com/files/documents/Michael_Kintner_Meyer.pdf Current generation capacity and distribution can provide 75% of current transportation. Steven Saylor, Chief Electrical Engineer, Vestas America, speaking to IEEE IAS meeting in Portland, OR: “Any two great plains states can meet the current U.S. electrical needs with wind power. Any time the prices of natural gas doubles, the number of wind sites that become competitive increases by a factor of 10.” Utility Wind Integration Group: http://www.uwig.org/Source: Steve Heckeroth, American Solar Energy Society Area needed to power U.S. electrical needs: 104 Square miles in SW Nevada Slides: Impacts of Plug-in-Hybrid Vehicles on Regional U.S. Power, Michael Kintner-Meyer, Pacific Northwest National Laboratory, www.plugincenter.com/files/documents/Michael_Kintner_Meyer.pdf Current generation capacity and distribution can provide 75% of current transportation. Steven Saylor, Chief Electrical Engineer, Vestas America, speaking to IEEE IAS meeting in Portland, OR: “Any two great plains states can meet the current U.S. electrical needs with wind power. Any time the prices of natural gas doubles, the number of wind sites that become competitive increases by a factor of 10.” Utility Wind Integration Group: http://www.uwig.org/

6. DOE Well-to-Wheels Comparison* Compares gasoline to electricity efficiency Tg: US average fossil-fuel generation efficiency = 0.328 Tt: US average transmission efficiency = 0.924 Tp: Petroluem refining and distribution efficiency = 0.83 C: KWH energy/gallon = 33.705 Eg = (Tg * Tt * C) / Tp = 12.307 KWH/gal Fuel Content Factor 1/0.15 = 6.67 This approach explains strange “MPG” ratings 230 “mpg” for Chevy Volt 373 “mpg” for Nissan Leaf I get about 6 mi/KWH (measure at wall) at 45 mph Insight was 70/50 mpg highway/urban About 200 mpg energy equivalent (72 mpg from fossil fuels)

7. PV + EV is Sun-to-Wheels Champ PV/EV sun-to-wheels efficiency ~16% PV cells 20% efficient sun-to-electricity EV >80% efficient electricity-to-wheels Bio-fuels sun-to-wheels efficiency <1% Alcohol sun-to-fuel is 1-2% in practice Heat engine <20% fuel-to-wheels May require other resources (H2O, land) Bio-fuels still useful for PHEV long trips Fossil fuel sun-to-wheels efficiency 0% Sun to fuel 10-10%, fuel to wheels <20% But utility generation + EV is more efficient than mobile heat engine with any fuel Example: >2X better for natural gas PV: Sunpower (SPWR) cells >20% EV efficiency: www.evalbum.com Alcohol efficiency from question at Portland Peak Oil talk by David Blume. Book: “Alcohol Can Be A Gas”, www.permaculture.com “The maximum theoretical sun-to-fuel efficiency is 14%, but in practice it is 1-2%”. Plug-in bio-diesel hybrids and wind generation is solution from book “Plan B v2.0”, Lester Brown, www.worldwatch.org PV: Sunpower (SPWR) cells >20% EV efficiency: www.evalbum.com Alcohol efficiency from question at Portland Peak Oil talk by David Blume. Book: “Alcohol Can Be A Gas”, www.permaculture.com “The maximum theoretical sun-to-fuel efficiency is 14%, but in practice it is 1-2%”. Plug-in bio-diesel hybrids and wind generation is solution from book “Plan B v2.0”, Lester Brown, www.worldwatch.org

8. My Conversion Experience

9. Selecting an Electric Vehicle Lightweight Lightweight Lightweight Aerodynamic Can hold weight of batteries (GVWR) Rule of thumb for lead-acid batteries: 30% of total vehicle weight is batteries Room for batteries

10. Where Does the Energy Go? Acceleration (hills) force = mass*acceleration Heating up tires (rolling resistance) force = mass*velocity Pushing air out of the way (esp. v > 40 mi/hr) force = frontal area * coefficient of drag * velocity2

12. Aerodynamic Efficiency

14. Theoretical Energy Calculations Rolling resistance (Fr) is proportional to weight and velocity Wind resistance (Ftd) is proportional to frontal area, coefficient of drag, and velocity squared Fh is acceleration (also hill climbing: 1 mph/sec is about 5% incline) Insight with LiIon batteries: 2200 lbs, 28 KWH, area 20.5 sq ft, Cd 0.25

15. Electric Motor Torque and Power

16. AC Motor Efficiency

17. Transmission EV’s have adequate torque at low RPM AC motors can go as high as 10,000 RPM Result: some EV’s don’t need gears, clutch Direct drive is common--saves weight Slower motor RPM is slightly more efficient

18. IMA and Batteries Removed

19. Front After Removing Engine and Transmission

20. Gas Tank Compartment

21. Engine View of Transmission

22. Adaptor Plate Design

23. Shaft Coupler Design

24. Adaptor Plate and Coupler

25. Shaft Coupler

26. Measuring for Motor Mount

27. Aligning Plastic Motor Mount Template

28. Template Marked for Engine Rotation

29. It Actually Fits!

30. Adjusting Motor Hanger Thickness

31. Mount, Hanger, Motor, Adaptor Plate

32. Mounted!

33. Mounting Motor Controller

34. Accelerator Pot Box

35. Power Brake Vacuum Pump

36. Cooling Motor and Inverter

37. Top Battery Box

38. Riveted Box Joints

39. Unmodified Main Contactor Box

40. High Voltage Wiring

41. Battery Box Installation

42. Heater Usually replace heat exchanger with electric heater Use DC-rated relay with magnetic blowout Liquid EV heater Pump included Thermostat included HV power control 2 or 4 KW models

43. Air Conditioning

44. “Temporary” Charger Installation

45. Charger Isolation Contactors

46. Use Appropriate Batteries

47. A123 Cells—Lots of Power

48. Past Time for a New Pack

49. Design In Safety Use DC-rated components Fuses: Buss FWH or Littlefuse KLKD Best placed connecting batteries in pack Contactors (relays) will open circuit if motor controller fails—once Best in both wires

50. Battery Balancing Relative cell state of charge varies over time Manufacturing variance Different operating temperature Series charging increases differences in state of charge Individual chargers is one solution Stop driving when lowest cell is empty Stop charging when highest cell is full (5% overcharge ok) But charger and instruments measure total pack voltage Ideally measure individual cell voltages Measuring highest, lowest batteries is good approximation

51. Capacity Variance with Aging As batteries age capacity variances increase More imbalance! Easier to overdrive Weakest cell voltage plunges and may even reverse polarity! Best case: shorter range Low temperatures also reduce effective capacity Eventually it’s time for a new pack! Lowest capacity cell is also overcharged Active automatic battery balancers mitigate extremes

52. Battery Management Add-ons Hart Batt-Bridge is an “idiot light” costing <$10 LED lights when two halves of pack differ by > 2v One cell empties/reverses first Charge now or go “turtle mode”! PowerCheq modules Keep each two adjacent batteries voltage difference < .1V Works 24X7 while driving, charging, parked Limited current—keeps balanced pack balanced Requires N-1 modules for N batteries

53. More Battery Management Aids Manzanita Micro MK3 regulator prevents overcharge Backs off charger when individual battery full Limits battery voltage Data logging Hart balancer relay module (30A capacity) Scans batteries to measure voltage Connects any battery to isolated “flying” battery or DC-DC Can take charge from higher state-of-charge batteries Gives charge to lower state-of-charge batteries

54. Operation and Maintenance The Insight is now 10 years old, 37300 mi Converted at 12000 mi 4 years on lead (2000 mi/yr with 25 mi range) 3 years on LiFePO (6000 mi/yr with 60 mi range) Maintenance Spent $240 checking brakes 2 new LRR tires Currently equalizing batteries manually every 10 months (BMS will do this continuously) Major expense: new custom seat covers Fuel costs 1.6 cents/mi (3% of electric bill) Battery depreciation estimate 6 cents/mi

55. Summary Respect high voltage and current Install service and emergency disconnects Keep connections tight--check temperature Use quality components within ratings Pick a strong, lightweight, efficient vehicle Adequate GVWR for batteries Upgrade clutch, brakes, suspension if needed Plan for adequate HP and proper drive ratio Too much torque may require drivetrain upgrade

56. Summary cont’d Use batteries with sufficient power “Golf cart” (flooded) or UPS (sealed AGM) are simple Advanced batteries may require cooling, BMS Don’t skimp on charging equipment Overcharging kills batteries, creates hydrogen Overheating during charging can cause fire Battery management is essential to long life For NiCd, NiMH, LiIon BMS is essential to safety Enjoy your quiet but powerful, economical EV!

57. References and Resources Electrification Coalition www.electricationcoalition.org DOE rules and regulations 36987, Federal Register, Vol 65, No. 113, June 2000 K. Deffeyes, “Beyond Oil”, ISBN 0-8090-2956-1 M. Simmons, “Twilight in the Desert”, ISBN 0-471-73876-X EV Album http://evalbum.com Electric Auto Association http://www.eaaev.org See “Convert to Electric Vehicles” in download section Oregon EV Associaton http://www.oeva.org Bob Brandt, “Build Your Own Electric Vehicle”, 1994, McGraw Hill Michael Brown, “Convert It”, 1993, Future Books.

58. Backup

59. World Peak Oil Source: Steve Heckeroth, American Solar Energy Society Book: “Beyond Oil”, Defeyes, Professor Emeritus at Princeton University, geologist Book: “Twilight in the Desert”, Matthew Simmons, energy investment banker Source: Steve Heckeroth, American Solar Energy Society Book: “Beyond Oil”, Defeyes, Professor Emeritus at Princeton University, geologist Book: “Twilight in the Desert”, Matthew Simmons, energy investment banker

60. Sun-to-Wheels Measure of Efficiency Source: Steve Heckeroth, American Solar Energy SocietySource: Steve Heckeroth, American Solar Energy Society