Illustration: Martin Woodtli This sad routine rarely varies: You spend a small fortune on a laptop that touts its extended battery life, and six months later you're running out of juice after an hour. Why is it that computermakers can squeeze 250 gigs of data storage into a 13-inch notebook, but they can't provide batteries that outlast your PowerPoint presentation?
Actually, battery manufacturers have made great strides over the past decade: A contemporary lithium-ion battery delivers double the juice of its early-'90s predecessors. But the power demands of laptops — and cell phones and digital audio players, for that matter — have soared as well. So instead of longer battery life, you've got a 2-GHz screamer that can burn DVDs, download songs, and search your hard disk all at the same time.
Things would improve if electronics designers and batterymakers worked harder to match power supplies with the demands of specific processors. But Moore's law doesn't leave much time for collaboration: Consumers expect their next laptop to run twice as fast as their old one, so manufacturers focus on just getting the latest CPUs into their machines. Batteries are an afterthought, purchased from the lowest bidder and rushed through the quality-assurance process, which means short run-times and the occasional laptop bonfire.
Eventually, the hydrogen fuel cell may evolve into a power source for portable electronics, but lithium-ion's reign is due to last another decade. What to do in the interim? Buy a second battery pack.
