A winding-type lithium ion battery includes an electrode assembly; the electrode assembly includes a first electrode plate, a separator, and a second electrode plate that are successively stacked and wound; the first electrode plate includes a first current collector and multiple first tabs electrically connected to the first current collector; the second electrode plate includes a second current collector and multiple second tabs electrically connected to the second current collector; the electrode assembly is flat, and a notch S is provided at least one corner of the electrode assembly.