Several components are responsible for the performance hit vs. long battery life in the IBM T Series and Electrovaya offerings. "What is causing the performance hit is slower moving drives, which may at times actually spin nearly all the way down between reads, processors working at a fraction of their potential on battery life, dimmer screens, and lower power fans," Enderle says.

Electrovaya largely attributes the Scribbler's long battery life to its patented LiIon, 75 watt-hour battery. The SC2100 also features a 1.3GHz Intel Centrino processor, a 12.1-inch display, 802.11g wireless capabilities, and an 80GB hard drive and weighs in at 3.5 pounds.

IBM's ThinkPad T43, introduced last month and available in April, weighs 4.5 pounds and is also equipped with an Intel Centrino processor that supports up to 2GB of DDR2 system memory. According to IBM, the new T43 can offer up to eight hours of battery life while running office applications, including Internet connectivity with an 802.11 connection.

Battle Of The Form Factors

HP (www.hp.com; 800/752-0900) this month attempted to shake up the battery life sector with the launch of the HP Compaq 6220/6230 notebook series that the company says can offer more than nine hours of battery life when a travel battery, which is sold separately, is added. The notebook's form factor enables the travel battery to be attached directly to the notebook so that it is simultaneously operable with the integrated battery. The notebook series, which offers Centrino CPU clock speeds up to 2.13GHz and a memory capacity of up to 2.048GHz, weighs in at 5.99 pounds when the travel battery is attached.

In addition to the Intel Centrino processor that offers SpeedStep power-saving controls and Intel's Display Power Saving technology for the screenwhich represents the most significant power-draining componentHP also says its patented NIC technology helps to lower power consumption on a BIOS system level.

Nine hours is also a realistic benchmark for the HP Compaq 6220/6230 notebook series when running typical applications, such as accessing the Web and checking email with the Centrino chipset's 802.11 capabilities, using a word processor or other applications, the company says. "Nine hours is a realistic test of what you would experience while sitting in a conference room in a, God forbid, nine-hour meeting," says Herman de Hoop, a worldwide technical marketing manager for HP.

ASUS (www.asus.com; 888/678-3688) also represents an OEM with a consistent notebook offering that at least keeps the vendor in the battery longevity notebook race. The company also relies on Intel's Centrino to regulate its latest M3Np notebook's power-saving features at clock speeds of 1.30GHz to 1.70GHz. With ASUS' Power4 Gear power-consumption technology, the company maintains the M3Np can operate more than five hours. The M3Np weighs about 5 pounds.

A 10-Hour-Plus Battery Life?

So what is in store for next-generation long-battery life notebooks? OEMs will likely continue to rely on power-saving capabilities of CPUs, as well as BIOS and other system tweaks to reduce notebook power consumption in future models, but no breakthroughs in battery technologies are in store for the near term. It will likely be several years before battery lives extend beyond 10 hours, which will probably involve replacing power-hungry LCDs with new display types, Locker says.

"I don't see battery life [extending to] up and beyond 10 hours [in the near future]. Inventing a new technology to replace the panels with OLEDs, for example, would do it, but that is four to five years out," Locker says. "However, [OLEDs] will also probably represent the next breakthrough on a system level.

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