Wound-type cell and winding mandrel

Abstract

The present disclosure provides a wound-type cell and a winding mandrel. The wound-type cell comprises: a first electrode plate having a blank first current collector which is positioned at a first winding start end and is not coated with the first active material layer; a second electrode plate having a blank second current collector which is positioned at a second winding start end and is not coated with the second active material layer, and the blank second current collector is positioned at an inner side of the blank first current collector; a separator; a first electrode tab; and a second electrode tab. A first end of the blank first current collector is beyond a second end of the blank second current collector in a length direction, and a position of the first electrode tab is beyond the second end of the blank second current collector in the length direction.

1 .- 16 . (canceled) 
     
     
         17 . A wound-type cell, comprising:
 a first electrode plate having a first current collector and a first active material layer coated on a surface of the first current collector, and the first electrode plate further having a blank first current collector which is positioned at a first winding start end and is not coated with the first active material layer;   a second electrode plate having a second current collector and a second active material layer coated on a surface of the second current collector, and the second electrode plate further having a blank second current collector which is positioned at a second winding start end and is not coated with the second active material layer, and the blank second current collector being positioned at an inner side of the blank first current collector in a thickness direction;   a separator provided between the first electrode plate and the second electrode plate to separate the first electrode plate from the second electrode plate;   a first electrode tab electrically connected to the blank first current collector; and   a second electrode tab electrically connected to the blank second current collector;   wherein   a first end of the blank first current collector is beyond a second end of the blank second current collector in a length direction, and a position of the first electrode tab is beyond the second end of the blank second current collector in the length direction;   at least a part of a third winding start end of the separator is folded back to an inner side in the thickness direction and is positioned between the first electrode tab and the second electrode tab in the length direction.   
     
     
         18 . The wound-type cell according to  claim 17 , wherein the third winding start end of the separator is formed by two layers in the thickness direction. 
     
     
         19 . The wound-type cell according to  claim 17 , wherein the first electrode plate is a positive electrode plate and the second electrode plate is a negative electrode plate. 
     
     
         20 . The wound-type cell according to  claim 17 , wherein
 a thickness of the first electrode tab is more than a thickness of the first current collector;   a thickness of second electrode tab is more than a thickness of the second current collector.   
     
     
         21 . The wound-type cell according to  claim 17 , wherein a side of the second current collector which directly faces the blank first current collector is not coated with the second active material layer. 
     
     
         22 . The wound-type cell according to  claim 17 , wherein a side of the first current collector which directly faces the blank second current collector is not coated with the first active material layer. 
     
     
         23 . The wound-type cell according to  claim 17 , wherein an inner side of an arc-shaped portion of the second current collector which directly faces the first end of the blank first current collector is not coated with the second active material layer. 
     
     
         24 . A winding mandrel, used for winding the wound-type cell according to  claim 17 ,
 wherein   the winding mandrel comprises a first winding mandrel and a second winding mandrel which are sequentially provided along the length direction, a first end surface of the first winding mandrel and a second end surface of the second winding mandrel face each other and form a clamping groove;   an end of the first end surface which is close to the blank second current collector is beyond an end of the first end surface which is away from the blank second current collector in the length direction;   an end of the second end surface which is close to the blank second current collector is beyond an end of the second end surface which is away from the blank second current collector in the length direction.   
     
     
         25 . The winding mandrel according to  claim 24 , wherein the first end surface and the second end surface are parallel to each other. 
     
     
         26 . The winding mandrel according to  claim 25 , wherein
 an angle between the first end surface and a first side surface of the first winding mandrel which is close to the blank second current collector is between 20 degrees and 70 degrees;   an angle between the second end surface and a second side surface of the second winding mandrel which is close to the blank second current collector is between 160 degrees and 110 degrees.   
     
     
         27 . The winding mandrel according to  claim 24 , wherein the third winding start end of the separator is formed by two layers in the thickness direction. 
     
     
         28 . The winding mandrel according to  claim 24 , wherein the first electrode plate is a positive electrode plate and the second electrode plate is a negative electrode plate. 
     
     
         29 . The winding mandrel according to  claim 24 , wherein
 a thickness of the first electrode tab is more than a thickness of the first current collector;   a thickness of second electrode tab is more than a thickness of the second current collector.   
     
     
         30 . The winding mandrel according to  claim 24 , wherein a side of the second current collector which directly faces the blank first current collector is not coated with the second active material layer. 
     
     
         31 . The winding mandrel according to  claim 24 , wherein a side of the first current collector which directly faces the blank second current collector is not coated with the first active material layer. 
     
     
         32 . The winding mandrel according to  claim 24 , wherein an inner side of an arc-shaped portion of the second current collector which directly faces the first end of the blank first current collector is not coated with the second active material layer.