Here's another one from the Department of Unintended Consequences:

Cars and trucks have become more like computers and other electronic gizmos. That's good for better fuel efficiency, emissions control, and overall vehicle performance and enjoyment.

But electronic devices become obsolete quickly. Today's popular hand-held communications gadget is tomorrow's technological junk. Have you ever tried donating a five-year-old desktop computer to a charitable organization? Many groups out there won't take it.

Similarly, today's electronics-laden cars are in danger of becoming tomorrow's forgettable items because of rapid advances in technology. That means cars could lose value in the manner of yesterday's iPod, laptop or video game. Consider, for example, the matter of batteries, which are becoming increasingly important in the continued development of hybrid gas-electric cars and trucks.

An estimated 88,000 hybrid vehicles, most of them from Toyota Motor Corp. and Honda Motor Co., were sold in the United States last year. Those models accounted for barely half of 1 percent of the 17.2 million new cars and trucks sold in the United States in 2004, according to J.D. Power and Associates, an international marketing-research firm in Westlake Village, Calif.

But hybrids are gaining popularity in the automotive world, thanks to higher petroleum prices and superior marketing hype. German and U.S. automotive manufacturers, companies that once eschewed hybrids in pursuit of hydrogen fuel-cell vehicles, which they still regard as the ultimate solution to car-caused environmental problems, are planning to put more hybrid models in their vehicle lineups.

J.D. Power analysts think that by 2012, gas-electric hybrids will account for 3.5 percent of all new cars and trucks sold in the United States. Other analysts, more bullish in their assessment of potential public acceptance of hybrids, think those models could account for 15 percent of all new U.S. vehicle sales by 2015.

Better batteries will accelerate hybrid sales, analysts predict. That's the good news for hybrid supporters. The bad news is that better batteries can and probably will undermine the resale value of vehicles with older batteries, such as the nickel-metal-hydride packs used in most of today's hybrid vehicles.

Nickel-metal-hydride batteries do relatively well in their current vehicle application, which primarily is an assistive mode. The batteries and electric motors take over the driving chores of hybrids in stop-idle-and-go urban traffic. Power responsibilities shift to the hybrid's gasoline engine on the highway.

But automakers nowadays are looking at the possibility of making the batteries and electric motors carry more of the power responsibilities on the highway. Doing so would conserve more fossil fuels and slash more tailpipe emissions.

In addition to extra power, the car companies also want smaller, lighter batteries. To get those things, they are looking at lithium-ion batteries as potential successors to today's nickel-metal-hydride packs.

In response to what it sees as a developing demand for "advanced power-storage systems," Johnson Controls Inc., one of the world's biggest automotive suppliers, last September established a lithium-ion battery research center near its headquarters in Milwaukee. In doing so, Johnson Controls served notice that it was taking on Japanese companies, such as Panasonic EV Energy Co. and Sanyo Electric Co., in pursuit of the car battery of the future.

All of the companies involved in lithium-ion research "are still a way off" from developing a durable, affordable lithium-ion car battery, one that actually can be designed as an integral part of a hybrid-vehicle drive system, rather than be installed as a bolted-on device, said Greg Sherrill, group vice president for the Automotive Group of Johnson Controls.

"We still have certain issues, such as improving the durability of lithium-ion batteries," which tend to be more vulnerable to damage than the nickel-metal-hydride type in the heat and vibration generated in the operating environments of cars and trucks, Sherrill said.

But, "We believe that lithium-ion batteries will be the wave of the future; and we're excited to be a leading organization in helping to drive this battery technology forward," he said.

Auto-industry analysts think companies involved in lithium-ion battery research are likely to come up with a marketable, breakthrough battery in the near future -- a development that would move the concept of gas-electric cars forward while effectively consigning the current generation of those models to the status of a played-out laptop.

The "glove box" -- part of the new Johnson Controls advanced lithium-ion battery development laboratory in Milwaukee -- is an explosion-proof chamber for applying electrolytes to battery cells.