To change the battery in a 2011 ford taurus key fob, watch: https://www.youtube.com/watchv=8hw8mfvnove this piece of the car will eventually become ineffective. the battery will need to be swapped out every 50,000 to 60,000 miles. it will costsome money, but you will have to cough up the cash to keep your car running. you will come into nasty problems with the battery during the life cycle of the car. the battery can drain quickly and will need to repaired. the battery can just be completely drained. you will need to recharge or replace it at this point. there can be a leak, causing the fluid to spill all over the place. a cracked case could come about and will need to be fixed completely.
To change the battery in your 2011 ford taurus pry open the key with a screwdriver, and replace it with a cr2032 battery.