NEEDED FOR TEST
Step 1: Battery to Be Tested
Make sure battery is free of dust , build up , etc
This test is 100% accurate and is good for sizes triple A , double A , C , and sometimes D depending on the individual and you'll see why.
Step 2: Test
Using your eyeteeth or tooth , (that's right your chompers) bite down slightly on the battery being careful not to peirce metal exterior (same pressure you would use to dent a number two pencil). If battery is easily dented it is practically brand new. If somewhat soft it is at the midlife point. If rock hard its dead as a doornail and time to replace.
Step 3: Attention
If battery is rock hard and you have no others to replace and need it to work just a few more times/hours I know a trick (not recommended/ somewhat unsafe). I do it to most if not all of my batteries mainly because I m just a wee bit on the lazy side. ;)
Take that battery outside and bounce it off the side walk a few times...It brings a wee bit of life back, enough for one more night with the television/directv/dish remote anyways.
Also its another way to confirm a dead battery , higher the bounce worse the battery