ASYNCHRONOUS HEATING AND CALENDERING DEVICE, LARGE WIDE ULTRA-THIN LITHIUM METAL FOIL, PREPARATION METHOD THEREFOR, AND APPLICATION THEREOF

Provided are an asynchronous heating and calendering device, a large wide ultra-thin lithium metal foil, and preparation method and use thereof, wherein the asynchronous heating and calendering device comprises: a pulling-substrate unwinding unit (E) for unwinding a pulling-substrate (P); a lithium strip unwinding unit (D) for unwinding a lithium strip (S); an asynchronous heating and calendering unit (H) which comprises: a first calendering roller (B), a second calendering roller (A) and a heating box (C), wherein the heating box (C) is used to heat the first calendering roller (B), the first calendering roller (B) heats the pulling-substrate (P), and the first calendering roller (B) and the second calendering roller (A) have parallel axes and are arranged opposite to each other, so that the pulling-substrate (P) and the lithium strip (S) are combined into a composite strip (Z); and a winding unit (G) for winding the composite strip (Z). A large wide ultra-thin lithium metal foil with a uniform thickness may be prepared by providing a heating box (C) and asynchronous first calendering roller (B) and second calendering roller (A) in said device, and the application of this lithium foil in batteries has a relatively high initial efficiency. The width of the lithium foil is 1-600 mm; the thickness of the lithium foil is 1-20 μm; and the initial efficiency of the battery reaches 98%.