Red light on charger blinks,on camera green light...

i hope you can help i have a casio ex-s2 exilim.my sister gave it to me and she said she thinks it needs a new battery because it wasnt charging,so i bought a new battery. when you put the camera on the charger the red light blinks.when you press the power button on the camera the green light flashes once and then nothing happens-the camera wont turn on. i really hope you can help me,i cant afford to buy a camera right now.