Andy's toys do so much talking and moving around you'd think their batteries would have run dry during the course of the film. Unlikely they'd have been fitted with new ones either since Andy's neglected them for so long.
shareTheir talking and moving about doesn't require batteries, unless they're actually using the features built with the toy.
For example, Buzz could run around and chit chatter for years on end without running out of batteries, as toys in this universe are "alive" much like you or I. But if you kept on pressing his buttons, which uses his speakers and lights, then of course he'd run out of batteries... Or better yet, his "suit" would run out of batteries so to speak. He would still be able to move around and talk, just his buttons wouldn't work.
Lastly, toys' batteries last a surprising amount of years lol
I agree with what Channel_E-D said. The toys only use their batteries for their special features. Most of Andy's toys aren't even battery operated like Woody, Bullseye, Jesse, Mr and Mrs Potato Head, Rex, Bo Peep, Hamm, Wheezy, Slinky etc. etc.
Also I think whenever the toys that did run on battery ran out of them, Andy did change the batteries. It's just that we are never shown this. Just like in most movies we are never shown the main characters eating or going to the bathroom etc. but we just assume that they do all that.
Also Buzz's quote, "We're going in the attic now, folks. Keep your accessories with you at all times. Spare parts, batteries, anything you need for an orderly transition." shows that even if Andy forgot to change the batteries, the toys did that themselves.
Mr McGee, don't make me angry. You wouldn't like me when I'm angry!
These are toys that walk, talk, and escape from tragic events in the absence of humans's presence.
I'm sure they would've discovers how to get batteries.
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The only toy that required batteries was Buzz. Don't forget that the toys aren't completely helpless. I'm sure they scavenged Andy's house for batteries whenever Buzz needed them.
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Solving Plot Holes 101: Learn to use your Critical Thinking skills.
This movie about animated talking dolls is not very realistic.
When a human is around a battery operated toy, like Buzz, or a toy with a pull string, the toy goes lifeless. But, when the human plugs in batteries, or pulls the string, the toy reacts, like when a powerful enough electrical current is sent through a cadaver. In this way, Andy is much like Dr. Frankenstein.
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A dope trailer is no place for a kitty.