Nickel-metal hydride/Price&Performance 01

Nickel-metal hydride, For Autos...The Benchmark of Price and Performance
by Shirley Georgi

(May 2003) To compete in the marketplace, Lead-acid must look at the benchmarks Nickel-metal hydride has set to date, being that this   battery system  is the popular commercial choice  for current hybrids on the market.  Because of its interest in plug-in hybrids, the Electric Power Research Institute (EPRI) has conducted several studies on hybrids, both non-plug-in (HEV-0) and plug-in (HEV-20 and HEV-60) and has compared results with conventional IC engine models. (Note that the HEV-0s in EPRI’s studies are “full” hybrids using a parallel design that deliver about 50% fuel economy  improvement, but does not use off-board electricity.)   Since the ELABC (European Lead Acid Battery Consortium)  is looking to  successfully replace a Nickel-metal hydride battery system with a VRLA (valve regulated Lead-acid) system in a Honda  Insight,  the information in this article  will only consider the HEV-O.
Can VRLA Lead-acid compete with Nickel-metal hydride in cost for replacement of Batteries in an HEV-0?

Microsoft Excel Chart
Approximate Battery Replacement Costs to Consumers using Nickel-metal hydride Batteries, given the fact that the batteries have a salvage value.

Compact Car        $1,200 to $1,400
Mid-size SUV     $1,900 to $2,600
Full-size SUV     $2,500 to $3,500

The EPRI study states that HEV-0  Nickel-metal hydride batteries will very likely deliver sufficient cycles for the 100,000 mile vehicle lifetime.  (Data is from EPRI study, “Comparing the Benefits and Impacts of Hybrid Electric Vehicle Options for Compact Sedan and Sport Utility Vehicles,” dated 07/02)

On March 23, 2003, EPRI in their most recent study, “Advanced Batteries for Electric-Drive Vehicles,” gave Nickel-metal hydride batteries  a glowing report.  This study assesses the state of this battery technology and presents one of the first life cycle cost analyses for vehicles with Nickel-metal hydride batteries. Perhaps a portion of their impetus to work with Nickel-hydride batteries is based on the success of the RAV-4 which traveled over 100,000 miles on the original batteries with “no appreciable degradation in  battery performance of vehicle range.” Projections for battery life suggest that  a possible 130,000 to 150,000 miles can be obtained.

In 2000, the battery technical advisory panel of experts reported on a new positive electrode additive to improve high temperature charge acceptance.  Most recently, Saft has also presented documentation on bench testing showing  that Nickel-metal hydride batteries have demonstrated 2,841 to 2,922 cycles between 80% and 20% SOC (state of charge).  This appears to be substantiated by tests at Ford Motor Company   where data shows that  considerably more than 2000 cycles between 100% and 20% SOC resulted in an improved  cycle life.  EPRI has concluded that “greater battery cycle life means it is highly probable that Nickel-metal hydride batteries can meet 130,000 to 150,000 lifetime mileage for an HEV-0.”
The EPRI (Electric Power Research Institute) Study - “Comparing the Benefits and Impact of Hybrid Electric Vehicle Options for Compact Sedan and Sport Utility Vehicles.”

Although EPRI has considerable  interest in Plug-in Hybrids, their study did include HEV-0 vehicles which are described as  non-grid connected, gasoline-only (or fuel-only), power assist, engine dominant and charge sustaining. Their report, finalized in July 2002, describes their summary and conclusions.

The intent of the study was to focus respondents on their preferences with respect to their choice of well-established power train, conventional or several hybrid options, not on any other differences in the vehicles itself.  Vehicles studied  focused on the  compact, mid-sized SUVs and full-size SUVs, both in hybrid form (non-grid connected, the HEV-0  and grid connected,  the HEV-20 and HEV-60) and the conventional IC engine.

Data presented in this article will only compare the HEV-0 models with the convention IC engine models.   

Some conclusions of the study are as follows:

- In surveying customer preference for HEV benefits the top three benefits that emerged were: 1. fuel cost savings 2. reducing maintenance  (cost and personal time) and        3. longer range - 50%  
-HEVs can be designed for compact, mid-size SUV and full-size SUVs
-HEVs can offer major efficiency improvements as well as substantial reduction in consumption of petroleum-based fuels and emissions of air pollution precursors (NOX and HC) and carbon dioxide over gasoline conventional vehicles.  
-Smog forming gases can be reduced by 10% for a compact HEV-0, by 19% for a mid-size SUV HEV-0 and 20% for a full-size SUV HEV-0.
Greenhouse (CO) emissions are reduced for an HEV-0 by 20% in a compact, 31% in a md-size SUV and 30% for a full-size SUV
-HEV-0 vehicles are in the early commercialization stage.   
The EPRI working group speculates that this is the result of decisions by the relevant manufacturers to subsidize this promising new automotive technology.

However, for the success of the  HEV-0, and ultimately plug-in hybrids, many variables must provide a positive direction. The cost of advanced batteries “is highly dependent on the establishment of a growth market situation, a predictable regulatory environment and consistent production volumes that encourage capital investment in production capacity and line automation by battery and automotive manufacturers,” said Bob Graham, EPRI’s area manager for transportation. (BD note: Perhaps the next study will need to focus on if/when and how these variables will be accomplished.)

For complete reports on the HEV-0 and the  HEV-20 and HEV-60 Plug-ins, including the most recent study, “Advanced Batteries for Electric-Drive Vehicles,” request copies from the EPRI Distribution Center, 1355 Willow Way, Suite 2478, Concord, CA 94520, Pleasant Hill, CA 94523 (800) 313-3774.

Other thoughts on  HEVs

In an article entitled “Are Hybrid Vehicles Worth it?” in the  IEEE Spectrum, March 2001, Lester B. Lave of Carnegie Mellon University and Heather L Maclean of the University of Toronto answer the question , “No.”  In the text, the authors compare the Prius to the Corolla and conclude that   “HEVs cost too much at present to make economic sense.”  Research at seems to confirm this statement. In comparing  the Carolla with the Prius, their research estimated that it would cost over $29,000 over a five year ownership period for a Prius, whereas a Corolla would only cost $26,000.  Factors included in this five year period were maintenance, insurance, repairs and financing. Hybrids also have more depreciation.  According to Jeannine Fallon of, with the hybrid technology advancing quickly, what seems really advanced now could be outdated in five years, reducing the vehicle’s resale value.   

Costs of  Energy Storage Systems - (Nickel-metal hydride batteries)
Can VRLA  compete with these retail equivalent  averages?
Microsoft Excel Chart
    Energy storage system for  an HEV-0     

          a compact     $2,399

          mid-sized SUV     $3,679

          full-size SUV     $4,390

The data  for cost is stated in 2001 dollars and is an average of the Base and ANL (Argonne National Laboratory) methods.  In the ANL method, electric components (i.e. battery) are assumed to be supplied by outside vendors.  Their costs include not only the cost of labor and materials, but also a partial mark-up that includes some research and development costs, supplier overhead and profit, and appropriate warranties.  In the Base Method, all costs are treated as the cost of labor and materials.  Manufacturer and dealer mark-ups are applied to all component costs and costs for vehicle development are also added. (Data is from EPRI study, “Comparing the Benefits and Impacts of Hybrid Electric Vehicle Options for Compact Sedan and Sport Utility Vehicles,” 07/02)

Lester Lave and Heather Maclean  see buyers attracted to  HEVs, not for their fuel economy and lower emissions, but rather  by the large electricity supply on board to power more applications in the vehicle. (Ed note: This large electricity supply  has really nothing to do with  hybrid configuration.)  Unfortunately, the good fuel economy incentive has not been a positive factor as  shown by sales of the  Honda Insight (a two seater which has the highest gas mileage, 51 m.p.g., as noted by Consumer Reports).  In  March 2003,  only 22 vehicles were sold nationwide in the U.S. Through the first three months of 2003, Insight sales declined 26 percent  compared to 2002.

Perhaps this is why GM is announcing such future hybrid pickups as the Silverado and Sierra.  These pickups will have an integrated starter/generator to charge a 42-Volt advanced Lead-acid battery pack found under the cabin’s rear seats.  The electronics control the charging and engine restart functions and also provide current up to 20 Amps for the 100-Volt supplemental power outlets.  The plugs can be used for power tools, camping equipment or other recreational gear. With large SUVs like the Hummer being popular today, this just might be what the type of hybrid the average consumer might truly want and purchase.

Retail Price Equivalents for a conventional vehicle (CV) vs.
 a gasoline fueled hybrid (HEV-0)

          CV          HEV-0

Compact          $13,963          $17,008
Mid-size SUV     $30.977          $35,708
Full-size SUV     $37,607          $42,989

An average of the Base and ANL Methods were used in calculating the retail price equipment in 2001 dollars.  In each model, the battery, Nickel metal hydride,  is more than 10% of the cost in hybrid vehicle.  

EPRI states that significant uncertainty exists regarding HEV retail prices.  Each OEM is expected to price products differently.  Many OEM prices consider not only costs and market demand but also proprietary considerations (e.g. shifting of costs of one product onto other product lines) .  The EPRI Hybrid Electric Working Group (representatives from the utility and automotive industries, the DOE, ARB, South Coast Air Quality Management  District and academic researchers) did not know how to quantify proprietary considerations.  (Data is from EPRI study, “Comparing the Benefits and Impacts of Hybrid Electric Vehicle Options for Compact Sedan and Sport Utility Vehicles,” 07/02)

In a most recent EPRI study, “Electric-Drive Vehicle Costs Can Soon be Competitive with Conventional Cars over Life of the Vehicle,”  released 03/26/03, EPRI says that lower costs and a doubling of battery life times -up to 150,000 miles - result in significantly reduced fuel and maintenance costs for electric drive vehicles, and over their lifetime will offset the higher initial price by the end of this decade.

In California where the pressure is still on to produce no/low emission vehicles, the California Air Resources Board continues its drive for environmentally friendly cars, and   will include a large “required” number  for hybrids. Prior to the ARB meeting in late April,   Roland Hwang, senior policy analyst for the Natural Resources Defense Council, estimated that as one of its alternatives, the Board could include 195,000 hybrid vehicles.  But, an even greater allocation, 1.6 million,  could be included for  new models with  “eco-friendly”  IC engines - those   “partial  zero-emission (PZEV)” gasoline cars  rated as super ultra-low emissions vehicles.  And Mr. Hwangs’ forecasts were pointed in the right direction,.  On April 24th, the Board ruled on a new requirement for 3.4 million PZEVs by 2010 and 420,000 hybrid cars, such as the Toyota prius and Honda Insight, by 2011.        (BD note: Although the  studies do not confirm that higher gas prices will entice consumer to buy hybrids, long term prices of gasoline in California at more than $2.10/gal. may convince some to do so. However, in other parts of the country such as the in Midwest, where gasoline is $1.40/gal., there may be little incentive.)

HEV-0 Life Cycle Can Reach Cost Parity with Conventional IC Vehicles

Nickel-metal hydride batteries are projected to  cost about $400/kWh, using  these assumptions:
- gasoline costs, using the ARB (California Air) Resources      Board) model, is $1.75/gal. gasoline
 - ARB 8% discount rates apply
- battery life improvements as discussed in the EPRI study,       “Advanced Batteries for Electric-Drive Vehicles,”are    implemented .  
- Refinements are made in  motor, controller, engine battery,  maintenance  and fuel economy costs  
- There is a minimum production volume of 100,000/yr. for   hybrid system components.

At this price, the net present value (NPV) would be:
- $500 less for a mid-size HEV-0 than its gasoline
   counterpart over a 150,000/10 year life
- $86 less for a full size SUV-HEV-0 than its gasoline
   counterpart over a 150,000/10 year life

With all of the leading automakers announcing introductions of HEVs, the power assist HEV market penetration is anticipated to exceed one million units by 2010.  Morgan Stanley predicted HEV sales in the US next decade at 10 to 15% of the 17 million annual sales.  

(Information is from “Advanced Batteries for Electric-Drive Vehicles: A Technology and Cost-Effectiveness Assessment for Batty Electric Power Assist Hybrid Electric, and Plug-in Hybrid Electric Vehicles, EPRI, Palo Alto, CA:2003. 1001577)   

One thing is for sure; with all the automakers committing to a hybrid design, the consumer will be hearing more and more about hybrids.  Those venturing out to buy will ultimately be the best or poorest salespersons for these vehicles.  Those new hybrid buyers will be comparing their new vehicles to their former models with conventional IC engines.  They will expect them to have a calendar life of 10 years without major repairs; they will expect  to drive them over hills and mountains and in temperatures from 1100F to -400F.  They will expect the vehicle to start and perform well even if left parked in a garage for two of three weeks.  Perhaps in another five years, there will be true consumer data that will make the difference in the success of hybrids. In either case, whether the hybrids are battery-powered by Nickel-metal hydride, advanced Lead-acid or another chemistry, all chemistries will be tried by the jury of consumers who will ultimately make the decision for the winner(s).