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There’s been an avalanche of news items lately about GM and Toyota and their planned use of lithium-ion batteries in PHEV (plug-in electric hybrid) cars. The bottom line is that GM seems to have stolen the tempo from Toyota (to borrow a piece of chess terminology), at least in the PR battle. (See links to some of the articles at the end of this post.)

You think a Tesla Roadster is news? Try flying in the Electra, a single-seater airplane with a 25 horsepower motor and 47 (105 lbs) kilograms of lithium-polymer batteries. Anne Lavrand, the president of the APAME group, said. "This will be a real aeroplane that will have an airworthiness certificate. It's a machine built for anyone with a pilot's license."

The Vectrix scooter weighs about 200 kilograms, while the lithium-ion-powered Enertia ($12,000), made by Brammo Motorsports of Ashland, OR, weighs just 125 kilograms. Brammo hopes that the lighter electric motorcycles will be appealing to those who would be intimidated by a heavier bike.

A zero emissions street legal Electric Motorcycle for light commuters and motorcycle enthusiast alike. The 14.2 kilowatt electric drive system and Hi-Power Lithium batteries allow this light weight electric motorcycle to briskly accelerate to freeway speeds.

Project Better Place, owned by Israeli-American entrepreneur Shai Agassi, will provide lithium-ion batteries to power the cars and the infrastructure to refresh or replace them. One battery will enable the cars to travel 124 miles per charge. Project Better Place will install parking meter-like plugs on city streets and construct service stations along highways to replace the batteries. [2] Renault-Nissan will build the new cars and will offer a small number of their existing electric models, such as the “Megane” sedan, at prices roughly comparable to gasoline models. To promote this form of environmentally efficient transportation, the Israeli government cut the tax rate on cars powered by electricity to 10 percent (from 79 percent on ordinary cars) to encourage consumers to buy the vehicles once they become available. [3] This initiative will offer consumers an inexpensive car for which they will pay a monthly fee based on expected mileage.

HySeries Drive plug-in hybrid. Electricity only for 25 miles (with a 336-volt lithium-ion battery pack). Serial hybrid, with the fuel cell (or think biofuel system) recharging the battery pack, not directly driving the wheels.

Without an electric drive with advanced lithium batteries, this is no different than what was originally developed. It could compete on the basis of price with the Aptera, which also is very sleek and thus requires fewer mega Joules to go the same distance. Perhaps, VW dealers can hope that shoppers won’t look for a plug. Now the question is, can it get a Five Star safety rating, like its competition?

EnerDel’s Li ion solution for the Electric Vehicle drive train is designed to have higher energy density than HEV cells and to enable vehicles to last up to a goal of 100 miles (160 kilometers) without recharging.

After safety, the longevity of the batteries in a plug-in hybrid is the greatest unknown. Can a plug-in hybrid’s battery pack retain the bulk of its energy capacity over 10 years of daily use and more than 4000 full-discharge cycles? (For a deeper look at the challenges facing plug-in hybrid batteries, see “Lithium Batteries Take to the Road”.)[ LINK: http://www.spectrum.ieee.org/sep07/5490 ] As Don Hillebrand of Argonne National Laboratory, in Illinois, said tartly, “Batteries are the showstopper.” Periodic demands from the grid, even for only a small fraction of the battery’s stored energy, would clearly affect the cells’ life span—but no one has data on how much. Another open issue is the development of creative financing models for replacement battery packs costing several thousand U.S. dollars even after mass production is achieved. Third-party battery leasing could be one answer, if combined with a secondary market for batteries whose performance has fallen below automotive levels. Carmakers, electric utilities, and large consumer-financing groups are quietly batting around these notions to see if they can build a financial model that makes sense for all three parties.

The new device also exhibits some unique electrical properties. While it can act like a traditional lithium-ion battery in that it stores energy and releases it as needed, it also has properties of a super-capacitor. These allow for quick discharges when necessary.

We examine the potential economic implications of using vehicle batteries to store grid electricity generated at off-peak hours for off-vehicle use during peak hours. Hourly electricity prices in three U.S. cities were used to arrive at daily profit values, while the economic losses associated with battery degradation were calculated based on data collected from A123 Systems LiFePO4/Graphite cells tested under combined driving and off-vehicle electricity utilization. For a 16 kWh vehicle battery pack, the maximum annual profit with perfect market information and no battery degradation cost ranged from ~$140 to $250 in the three cities. If the measured battery degradation is applied, however, the maximum annual profit (if battery pack replacement costs fall to $5,000 for a 16 kWh battery) decreases to ~$10-$120. It appears unlikely that these profits alone will provide sufficient incentive to the vehicle owner to use the battery pack for electricity storage and later off-vehicle use. We also estimate grid net social welfare benefits from avoiding the construction and use of peaking generators that may accrue to the owner, finding that these are similar in magnitude to the energy arbitrage profit.

The effects of combined driving and vehicle-to-grid (V2G) usage on the lifetime performance of relevant commercial Li-ion cells were studied. We derived a nominal realistic driving schedule based on aggregating driving survey data and the Urban Dynamometer Driving Schedule, and used a vehicle physics model to create a daily battery duty cycle. Different degrees of continuous discharge were imposed on the cells to mimic afternoon V2G use to displace grid electricity. The loss of battery capacity was quantified as a function of driving days as well as a function of integrated capacity and energy processed by the cells. The cells tested showed promising capacity fade performance: more than 95% of the original cell capacity remains after thousands of driving days worth of use. Statistical analyses indicate that rapid vehicle motive cycling degraded the cells more than slower, V2G galvanostatic cycling. These data are intended to inform an economic model.