te of California Air Resources Board
Sacramento, California
By
The Year 2000 Battery Technology Advisory Panel
Menahem Anderman
Fritz R. Kalhammer
Donald MacArthur BTAP 2000 FINAL REPORT
TABLE OF CONTENTS (DRAFT!)
I.

Section I: Introduction
Background
I.1.

Purpose and Scope
I.2.

Study Approach
II

Section II: Electric Vehicle Batteries
Background
II.1.

Battery Targets and Requirements
II.1.1.

Performance
II.1.2.

Durability / Life
II.1.3.

Safety
II.1.4.

Convenience
II.1.5.

Cost
II.2.

Candidate Batteries
II.3.

Battery Cost Factors
III

Section III: Findings
III.1.

Nickel Metal Hydride
III.2.

Lithium Ion
III.3.

Lithium Polymer
III.4.

Car companies
IV Section IV: Conclusions
Appendices
Glossary of terms
References EXECUTIVE SUMMARY
Five years after the modification of the 1990 Zero Emission Vehicle regulation,
and after a period of intensive effort to develop, demonstrate and evaluate advanced
electric vehicles, one key question in the electric vehicle debate [still] is whether batteries
can be available in 2003 that would make electric vehicles acceptable to a large number
of owners and operators of automobiles? The answer to this question is a key
input to the California Air Resources Board's ZEV regulation review required this year.
The authors of this report were asked to assist ARB in developing an answer, working
together as a new Battery Technical Advisory Panel (BTAP 2000).
The Panel focused its investigation on candidate EV battery technologies that
promise major performance gains over lead acid batteries, appear to have some prospects
for meeting EV battery cost targets, and are now available from low volume production
lines or, at least, laboratory pilot facilities. In the view of the Panel, other types of
advanced batteries not meeting these criteria are highly unlikely to be commercially
introduced within the next 5-6 years.
The Panes approach was similar to that of the 1995 BTAP: visits to the leading
developers of advanced batteries and to major automobile manufacturers engaged in
electric vehicle development, EV deployment, and in the evaluation of EV batteries;
follow-on discussions of the Panels observations with these organizations; Panel-internal
critical review of information and development of conclusions; and preparation of this
report. To assist the Panel members with the development of judgment and perspective,
they were given business-confidential technical and strategic information by nearly all of
the Panels information sources. This report, however, contains unrestricted material
only. The most important findings and conclusions of the Panel follow.
Nickel-metal hydride (NiMH) batteries capable of meeting the power
requirements for EV propulsion have been demonstrated in more than 1000 vehicles in
California. Bench tests and recent technology improvements in charging efficiency and
cycle life at elevated temperature indicate that NiMH batteries have realistic potential to
last the life of an EV, or at least ten years and 100,000 vehicle miles. Several battery
companies now have limited production capabilities for NiMH EV batteries, and plant commitments in 2000 could result in establishment of manufacturing capacities sufficient
to produce the battery quantities required under the current ZEV regulation for 2003.
Current NiMH EV battery modules have specific energies of 65 to 70Wh/kg, comparable
to the technologies of several years ago, and major increases are unlikely. If NiMH
battery weight is limited to an acceptable fraction of EV total weight, the range of a
typical family EV in real world driving is limited to approximately 70 to 100 miles on a
single charge.
Despite extensive cost reduction efforts of the leading NiMH EV battery
developers, NiMH battery cost remains the largest obstacle to EV commercialization in
the near term. Battery manufacturers and some carmakers projected future NiMH EV
battery costs for increasing levels of production. From these projections, battery module
specific costs of at least $350/kWh, $300/kWh and $225-250/kWh can be estimated for
production volumes of about 10k, 20k and 100,000 battery packs per year, respectively.
To the module costs, at least $1,200 per battery pack (perhaps half of that amount in true
mass production) has to be added for the other major components of a complete EV
battery, including the required electrical and thermal management systems. On that basis,
and consistent with the Panels estimates, NiMH batteries for the EV types now deployed
in California EV would cost EV manufacturers between $9,500 and $13,000 in the
approximate quantities (10k-20k packs per year) required to implement the year 2003
ZEV regulation, and approximately $7,000 to $9,000 at the 100,000 packs per year level.
These projections exceed the automobile manufacturers cost goals by about $7,000 to
$9,000 in the nearer term and by approximately $5,000 at automotive mass production
levels.
The reliability of the Li Ion EV batteries in the ALTRA EV has been excellent up
to now, but the battery durability test data obtained in all major lithium ion EV battery
development programs indicate that battery operating life is typically only 2-3 years at
present. Current Li Ion EV battery technology also does not pass some of the tests used to
gage battery safety under simulated abuse conditions. Resolution of these issues, the
production of pilot batteries and their in-vehicle evaluation, and fleet testing of prototype
Li Ion batteries meeting all critical requirements for EV application are likely to require
at least three to four years. Another two years will be required to establish a production plant, verify the product, and scale up to commercial production. Based on cost estimates
provided by developers and the Panels own estimates, these batteries will cost
substantially more than NiMH batteries at a production volume of around 10,000 packs
per year. Even in much larger production volumes, Li Ion EV batteries will cost less than
NiMH only if substantially less expensive materials become available, and after
manufacturing technology combining high levels of automation, precision and speed is
developed.
Lithium metal polymer EV batteries are being developed in two programs aimed
at technologies that would cost $200/kWh or less in volume production. However, these
technologies have not yet reached key technical targets including cycle life and are in the
pre-prototype cell stage of development. It is unlikely that the steps required to achieve
commercial availability of Li Polymer batteries meeting the performance and life
requirements as well as the cost goals for EV propulsion can be completed in less than 7
to 8 years.
The six major automobile manufacturers serving the California market have
invested extensive financial and talent resources in developing and deploying a diversity
of electric vehicles and in the evaluation of advanced EV batteries. The performance and
reliability of the more than 1400 EVs deployed with advanced batteries (most of them of
the NiMH-type) has been excellent for some and generally adequate for nearly all of
them. Automobile manufacturers stress, however, that NiMH and other advanced
batteries will be too expensive for acceptable EVs costs. Also, the practical range
provided by the batteries of current EVs is considered less than desirable by most drivers.
Larger batteries that could increase range would aggravate the battery cost problem as
well as raise increasingly serious volume and weight issues. In general agreement with
the Panels assessment, the automobile manufacturers projections indicate that both,
major technology advances and true mass production would be required to reduce
advanced battery costs substantially below current projections. This is considered
unlikely for the next 6-8 years.
All major carmakers are now actively pursuing alternatives to the currently
deployed EV types advanced-technology vehicles such as hybrid and mini EVs to
achieve emissions reductions. Like conventional EVs, HEVs and mini-EVs depend on improved batteries for their technical and cost feasibility. However, they require only a
fraction of an EVs battery capacity depending on vehicle technology and application,
between approximately 5% and 50%. Battery cost thus is substantially reduced, and with
it one of the largest barriers to the commercial viability of these new automotive
products.
The Panel was made aware of the impressive battery technology progress
achieved in this area by several of the EV battery developers. There is little doubt that the
development of NiMH and Li Ion battery technologies for HEV and mini-EV
applications has benefited directly and substantially from EV battery development.
Conversely, the successful commercialization of HEVs now and, possibly, mini-EVs in
the future can be expected to result in continued improvements of advanced battery
technologies. Over the longer term, these advances together with likely advances in
electric drive technologies and reductions in vehicle weight might well increase
performance and range, and reduce the costs, of electric vehicles to the point where they
appeal to broad markets. SECTION IV
CONCLUSIONS
From the Panels discussions with battery developers and major automobile
manufacturers engaged in the development and evaluation of electric vehicle batteries,
and based on the Panels own analysis of the information collected in these discussions,
the BTAP members have agreed on the following conclusions:
1.

Nickel-metal hydride (NiMH) batteries promising to meet the power and
endurance requirements for electric vehicle (EV) propulsion have been
demonstrated in vehicles and could be available by 200