The affected units include those sold between September 2005 and December 2006; Apple is providing an online form where you can enter your nano’s serial number and see if you’re eligible for a replacement unit. If your unit is covered, you can ship it in and you’ll receive a replacement model in six weeks. The company notes that personalized iPods will be replaced with non-personalized units.
Apple published a statement in 2008, attributing the fault to the batteries from a specific supplier; the company said that the issue only occurred “in very rare cases” and that it had received reports of less than 0.01 percent of units actually experiencing the problem. The new page for the replacement program does acknowledge, however, that the likelihood of an incident increases as the battery gets older.