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The need for powering portable equipment and electric vehicles has resulted in an intense battery development program. The resulting electrochemical systems deliver over 100 watthours per kg of battery mass. Achieving this high energy-density in the new batteries requires separating the structural and current-carrying components from the electrochemical components, and optimizing their design. Building these lightweight, high-performance cells requires a sophisticated manufacturing process that must be precisely controlled. For example, lithium, an anode in lightweight cells, is also very combustible, and a comprehensive test program is required before any lithium cell is introduced to the market to assure that under no conceivable condition will the cell start a fire. Thus every manufacturing step must be monitored. In this paper we describe a new tool, pressure-indicating film, that is being used in controlling manufacturing steps.

New energy-and-power management technology makes low-pollution hybrid electric vehicles practical and competitive in performance with gasoline powered cars. The fuel-burning engine can now run at its most efficient speed and load, with the propulsion motor supplying acceleration power and the generator capturing deceleration power. Battery depth of discharge can be monitored and controlled to get long battery life. A heavy battery is not needed for long travel distance. For example, the new Toyota Prius hybrid car delivers 66 miles per gallon in city driving and has a range of 600 miles on a tankful of gasoline. When acceleration power is supplied from a battery, then the engine can be a high-efficiency type, such as the 43-percent efficient Meijer version of the Stirling-cycle engine. Hydrogen, a previously impractical engine fuel, can be burned in external-combustion Stirling engines. Hydrogen can now be compactly stored in carbon nano-tubes or lithium aluminum tetrahydride.

Bicycle commuting, widely practiced in cities in Europe and China, offers to the user convenience of (1) route flexibility, (2) transportation at each end of the commute, (3) avoidance of waiting for public vehicles at stations, (4) avoidance of time wasted while public vehicles stop to load and unload other passengers. Electric propulsion, proposed for bicycles as early as 1924, would make possible constant speed for all bicycles in a freeway lane. For example, a freeway lane carrying only bicycles traveling at 18 km per hour could deliver 8000 commuters per hour versus 2000 automobiles per hour. Our analysis and tests show that a 100 km range between charges is feasible with a gross weight of 136 kg (300 lb), which includes the cyclist. A bicycle does not offer air-conditioned comfort for the rider, but its other advantages include (1) ability to operate in downtown zones after fuel-burning vehicles are prohibited, and (2) feasibility of stacking on racks in downtown parking space.

The Earth's rotation is slowing, making us add a leap second to our year, once every two to four years. Power extracted from the Earth's rotation now pushes tides and ocean currents. A simple mechanical analog shows how energy can be extracted and dissipated from a rotating body. A Coriolis force pushes on Earth-surface objects that move northward or southward. German artillery officers who didn't understand Coriolis effects missed Paris with their Big Bertha shells during World War II. An analysis shows that 45 degrees is the best latitude for extracting power by slowing the Earth's rotation. We calculate the contribution of Coriolis force for accelerating a magnetically levitated and guided train that travels in an evacuated tunnel, in a slightly southwest direction.