Hi Allyson
the Freelander 2 key fob battery is charged only when its placed in the ingition socket.
Its a sealed unit , if its not working I'd suggested contacting the dealer.
If you need to gain entry to the car it does have a manual key you can use (your owners handbook will tell you how to use it).
LR do recommned using the spare fob every 6 months (if memory serves me) so as to kept it charged up.