In the top right corner of the battery compartment there is a cutout where you can use your fingernail or small screwdriver to pry it out. You shouldn't need to though. Pressing alt+shift+del will restart the phone.
i put a piece of tape on it so i just grab the tape and pull on it.
there's a post somewhere on this,and shows pictures of it with the tape on it
I've been using this trick since it was first posted and it works great. Saves you from the potential of scratching the bezel if you have to use a pry tool. My battery is super hard to get out without the tape trick, but with it it's a breeze
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