TO paraphrase Reebok, the athletic-shoe company, computer-battery life is short. Too short. You know this because:
* Businesswomen crawl under assorted office furniture to plug in their laptop computers.
* Grown men fret that their portable wonders will run out of juice midway through their sales presentations.
* Your best travel tip is which airports have seats placed next to wall sockets.
Batteries, in other words, are crucial to portable computing. Their limits define how mobile we are. Their breakthroughs determine whether future gizmos will really be powerful and useful.
We're at the beginning of one of those battery breakthroughs. I got my first glimpse of this a few weeks ago when AST Research sent me a portable computer, the Ascentia 910N. It's powered by a new lithium-ion battery.
Batteries depend on chemicals to store and release energy. Portable computers started out on alkaline batteries. Then came nickel-cadmium. Then nickel metal-hydride or NiMH, today's standard. The move to lithium-ion chemistry is a big step. Sony, the leading maker of the new batteries, claims they are 30 percent lighter and deliver up to 30 percent more energy per cubic inch than NiMH. Proponents believe lithium-ion represents the next generation for portable computing.
After a month with AST's Ascentia, I'm a believer too. Instead of two hours with nickel-cadmium batteries on my old computer, I got six hours of constant use. On days when my computer needs were moderate, I could even skip a day before recharging. The clincher came one morning after I inadvertently left the machine on all night. To my delight, the Ascentia was still running.