article_snippet: These showed nothing unusual except for the one previously undisclosed fact of the battery's expiry date.
article_snippet: There is some extra margin in the design to account for battery life variabilty and ensure that the unit will meet the minimum requirement,’ the unit said.
article_snippet: However, once beyond the expiry date, the (battery's) effectiveness decreases so it may operate, for a reduced time period until it finally discharges,’
article_snippet: While it is possible the battery will operate past the expiry date,
article_snippet: ‘the battery is not guaranteed that the battery will work or that the battery would meet the 30-day minimum requirement,’ said The report by an independent investigation group.