Derived from the Italian verb "sbatti" it shows your lack of desire of doing something. It is used as slang amongst english-speaking/italian teenagers who are cool.
Bob: Let's meet Parky at the shop Jimmy: Nah, sbates
OR
Tommy: You wanna go to the pool Harry: Sbates, it's too far
Short form of the Italian word "sbattimento", meaning something stressful you wouldn't want to deal with, something effort-requiring you don't feel like doing
Used as an exclamation, especially in Northern Italy
Much in the same way Riker's Beard signified Star Trek: The Next Generation finding itself, and much in the same way Jump the Shark led to Happy Days' demise, Negan's Bat is a TV trope signifying an unprecedentedly awful cliffhanger, which makes no sense and leads to a butchering of iconic and beloved scenes.
Origins of this phrase come from Season Six of the Walking Dead, which ended on a cliffhanger showing a first person POV of Negan's Bat.