In France, the validity of identity cards has recently been extended by 5 years (in 2014).
But beware, there are conditions to be respected for your card to be concerned by this extension.
First of all, here is the reference text on the administration website.
The extension of five years for identity cards concerns: The new secure identity cards (plastic cards) issued from January 1, 2014 to adults.
Secure identity cards issued (laminated cards) between January 2, 2004 and December 31, 2013 to adults
In other words, if you have a card obtained before 2014 and you were under the age of majority when you obtained it, then your card is not affected by the extended validity period.