Sony PS3 Repair Manual page 31

PS3 Controller Disassembly
Now detach the battery by pulling it straight out. Take off the piece of plastic that is between the r1 and
r2 buttons and the one between the l1 and l2 buttons.
Now in order to get the main board off you must unscrew the screw on the board. Once that's out you
should be able to lift it out of there.
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