Waste lithium ion battery crushing and screening method and system

The invention provides a waste lithium ion battery crushing and screening method which comprises the following steps that waste lithium ion batteries are placed in a battery feeding device, and the battery feeding device conveys the waste lithium ion batteries into an electrified crushing device; crushing the waste lithium ion battery in an electrified crushing device; the crushed materials are conveyed into a low-temperature drying system, and the electrolyte is dried; the dried crushed materials enter a first-stage screening system, and the dried materials are screened according to the size; after the materials are screened by the primary screening system, the materials with the size larger than 2 mm are fed into the diaphragm sorting system, and diaphragms are screened out through airflow winnowing; 0.15-2mm materials screened by the first-stage screening system are conveyed into the fine crushing system; the materials crushed by the fine crushing system enter the secondary screening system for secondary s