Ever since the debut of Apple's iPod in 2001, the ubiquitous gadget has earned praise for its ease of use and its storage capacity, basically allowing music fans to tuck their CD collection into their pockets.

However, this iPod invasion (more than 2 million are currently in circulation) has also attracted its share of scorn for what some are calling the hit-or-miss life expectancy of its built-in rechargeable battery. Apple claims the iPod's lithium ion battery lasts eight hours per charge, but some users have seen theirs conk out in a fraction of that time -- or stop working entirely -- not long after the device's one-year warranty expires.

Recently, the company launched a battery-replacement program ($99 for a new one, $59 for an extended warranty), but not before some users took their gripes public.

In September, 22-year-old Casey Neistat discovered that the battery in his first-generation 5-gigabyte iPod could no longer hold a charge for more than an hour. At the time, Apple's advice to Neistat was to buy a new iPod. With new models priced between $299 and $499, Neistat instead decided to make a little noise. Neistat's ipodsdirtysecret.com, which launched in November, features a video of the New Yorker spray painting the phrase "iPod's unreplaceable battery lasts only 18 months" all over lower Manhattan.

"My brother and I made the movie in response to Apple not offering any alternative when your iPod battery dies other than buying a new iPod," Neistat said. "Their policy ... seemed to me to be an audacious, exploitative thing."

In the film, Neistat is heard calling Apple support and being told that the company doesn't offer a battery replacement and that his best bet is to purchase a new iPod, or he can send in his iPod and pay a $255 repair fee. Neistat tried to save money by buying a third-party replacement battery for $50, but he broke his iPod while trying to install it. In the end, he shelled out another $400 for a new iPod.

Apple's new program launched just as Neistat's video was hitting the Web, and the young filmmaker calls the revised Apple policy fair.

An Apple spokesperson, who asked not to be named, said the company has never made specific promises about the lifespan of an iPod battery because "it's hard to predict how a customer will use a product." The company directs users to an independent Web page with advice on how to maximize battery life at www.ipodbatteryfaq.com.

The batteries used in iPods are similar to those found in laptops and wireless phones and are made to last for 300 to 500 charge/discharge cycles (by comparison, replacement laptop batteries can cost anywhere from $80 to $170). The Apple spokesperson said the company has received feedback from customers whose original-edition iPods have retained their battery life and others whose battery issues have been resolved through software updates, but the spokesperson declined to comment on how many complaints have been received.

"These problems are fairly typical with these kinds of devices if they are used a lot," said Josh Bernoff, principal analyst for technology consultants Forrester Research. "The nature of the iPod is that it was very carefully designed, and I'm sure the space left for the battery was constrained by everything else they had to put in there."

Bernoff said the power demands of hard-drive-based devices like the iPod are much greater than those of electronics that run on standard AA or AAA nickel or alkaline batteries. Processor speeds continue to go up, and smaller components are constantly developed, but Bernoff said battery power for portable devices will continue to be a problem until "some miraculous battery technology pops up on the horizon," which he doesn't see happening in the near future.

Even music fans without the latest technology can feel the power pinch, easily spending $50-$100 a year on AA batteries to keep their portable CD players spinning.

And until better batteries come along, iPod fanatics like Karen Nicoletti will just have to make do. Nicoletti bought a first-generation 10 GB iPod in November 2002, and it died in December 2003, leaving her collection of thousands of tunes in suspended animation.

"I played around with it and tried everything to get it working again," said Nicoletti, 27, who was so attached to her device that she swaddled it in special protective cases and gave it a nickname, Poddy O'Macintosh. "If I spend $400 on something, I expect it to last more than a year. I went from having thousands of songs at my disposal to none."

Nicoletti, a Bay Area resident who used her iPod during her daily two-hour commute, hasn't decided whether to repair or replace her iPod, but she shared a vision she recently had. "The Macworld Expo was going on this week, and I had this dream of going down there with a sign that had a tombstone and the words 'November 2002 to December 2003' on it," she said.

The San Francisco law firm of Girard Gibbs & De Bartolomeo LLP took more concrete action, filing a class-action lawsuit on December 23. The case alleges that Apple has engaged in unfair and deceptive business practices and false advertising in its claims about the iPod, whose battery the suit claims is touted in product literature as lasting the lifetime of the player.

A judge has yet to rule on the suit's class-action status; the Apple spokesperson said the company does not comment on pending litigation.

For complete digital music coverage, check out the Digital Music Reports.