George's New Dinosaur is an episode of the 4th Season.
One day, Mr. Dinosaur's tail breaks off with George noticing this (and crying) when he goes to bed during the night. The following day the Pigs go off to Mr. Fox's Shop to buy a new one, a battery operated one called "Dino-Roar".
In the end, George finds playing with this new one harder than his old one, he couldn't play with Dino-Roar in the garden, he couldn't play with him in the bathtub (The water would break the electrical components in the toy) and during bedtime, the toy accidentally wakes Peppa up, thus leading to Daddy Pig turning him off.
The next day, George cries after not getting to play with him anywhere, only to let Daddy Pig remind him that he can still play with the toy. That's until the Batteries inside him round down up until 23! Peppa picks them all and then she finds Mr. Dinosaur's Tail!
In the end, Daddy Pig mends Mr. Dinosaur and George is a happy Piggy again.