Cell and electrochemical device

Abstract

The present disclosure provides a cell and an electrochemical device. The cell comprises: a first electrode plate comprising a first current collector and a first active material layer, a second electrode plate comprising a second current collector and a second active material layer; a first electrode tab, a second electrode tab, a separator. The first current collector has a first surface uncoated region; the second current collector has a second surface uncoated region; the first electrode tab is provided on the first surface uncoated region, the second electrode tab is provided on the second surface uncoated region. The first electrode tab and/or the second electrode tab are enlarged in length and width. When the cell is subjected to a mechanical shock, the first electrode tab and the second electrode tab are deformed to puncture the separator therebetween, so the first current collector and the second current collector are electrically connected.

What is claimed is: 
     
       1. A cell, comprising:
 a first electrode plate ( 1 ) comprising a first current collector ( 11 ) and a first active material layer ( 12 ) which is selectively provided on a surface (S 11 ) of the first current collector ( 11 ) and contains a first active material;   a second electrode plate ( 2 ) opposite to the first electrode plate ( 1 ) in electric polarity, comprising a second current collector ( 21 ) and a second active material layer ( 22 ) which is selectively provided on a surface (S 21 ) of the second current collector ( 21 ) and contains a second active material;   a first electrode tab ( 3 ) provided and electrically connected to the first current collector ( 11 ) of the first electrode plate ( 1 );   a second electrode tab ( 4 ) provided and electrically connected to the second current collector ( 21 ) of the second electrode plate ( 2 ); and   a separator ( 5 ) provided between the first electrode plate) and the second electrode plate ( 2 );   the surface (S 11 ) of the first current collector ( 11 ) having a part which is not provided with the first active material layer ( 12 ) thereon and this part being defined as a first surface uncoated region (B 11 );   the surface (S 21 ) of the second current collector ( 21 ) having a part which is not provided with the second active material layer ( 22 ) thereon and this part being defined as a second surface uncoated region (B 21 );   the first electrode tab ( 3 ) being provided on the first surface uncoated region (B 11 ) and the second electrode tab ( 4 ) being provided on the second surface uncoated region (B 21 );   the first electrode tab ( 3 ) extending toward two opposite transverse edges (TE 11 ) of the first surface uncoated region (B 11 ) along a width direction (W) and one side edge ( 31 ) positioned outside in the width direction (W) being close to one corresponding transverse edge (TE 11 ) of the first surface uncoated region (B 11 ), and the first electrode tab ( 3 ) extending toward two opposite longitudinal edges (LE 11 ) of the first surface uncoated region (B 11 ) along a length direction (L) and two outer side edges ( 32 ) in the length direction (L) being close to the two longitudinal edges (LE 11 ) of the first surface uncoated region (B 11 ), respectively; and/or the second electrode tab ( 4 ) extending toward two opposite transverse edges (TE 21 ) of the second surface uncoated region (B 21 ) along the width direction (W) and one side edge ( 41 ) positioned outside in the width direction (W) being close to one corresponding transverse edge (TE 21 ) of the second surface uncoated region (B 21 ), and the second electrode tab ( 4 ) extending toward two opposite longitudinal edges (LE 21 ) of the second surface uncoated region (B 21 ) along the length direction (L) and two outer side edges ( 42 ) in the length direction (L) being close to the two longitudinal edges (LE 21 ) of the second surface uncoated region (B 21 ), respectively;   the first electrode tab ( 3 ) and the second electrode tab ( 4 ) being spaced apart from each other in the width direction (W), and the separator ( 5 ) being presented between the first electrode tab ( 3 ) and the second electrode tab ( 4 );   when the cell is subjected to a mechanical shock, the first electrode tab ( 3 ) and the second electrode tab ( 4 ) being deformed to puncture the separator ( 5 ) between the first electrode tab ( 3 ) and the second electrode tab ( 4 ) such that the first current collector ( 11 ) and the second current collector ( 21 ) being electrically connected.   
     
     
       2. The cell according to  claim 1 , wherein
 the first electrode tab ( 3 ) is welded to the first current collector ( 11 ) of the first electrode plate ( 1 ) or is formed by cutting the first current collector ( 11 ) of the first electrode plate ( 1 ); and/or   the second electrode tab ( 4 ) is welded to the second current collector ( 21 ) of the second electrode plate ( 2 ) or is formed by cutting the second current collector ( 21 ) of the second electrode plate ( 2 ).   
     
     
       3. The cell according to  claim 1 , wherein
 the first electrode tab ( 3 ) and the second electrode tab ( 4 ) each have a thickness of TT, and 5 μm≤TT≤100 μm;   the first electrode tab ( 3 ) and the second electrode tab ( 4 ) each have a length of LT, and 10 mm≤LT≤500 mm;   the first electrode tab ( 3 ) and the second electrode tab ( 4 ) each have a width of WT, and 2 mm≤WT≤250 mm.   
     
     
       4. The cell according to  claim 1 , wherein
 a minimum distance between the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned outside in the width direction (W) and the one corresponding transverse edge (TE 11 ) of the first surface uncoated region (B 11 ) is 3 mm;   a minimum distance between the each outer side edge ( 32 ) of the first electrode tab ( 3 ) in the length direction (L) and the one corresponding longitudinal edge (LE 11 ) of the first surface uncoated region (B 11 ) is 3 mm;   a minimum distance between the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned outside in the width direction (W) and the one corresponding transverse edge (TE 21 ) of the second surface uncoated region (B 21 ) is 3 mm;   a minimum distance between the each outer side edge ( 42 ) of the second electrode tab ( 4 ) in the length direction (L) and the one corresponding longitudinal edge (LE 21 ) of the second surface uncoated region (B 21 ) is 3 mm.   
     
     
       5. The cell according to  claim 1 , wherein a distance between the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) is 1 mm˜5 mm in the width direction (W). 
     
     
       6. The cell according to  claim 1 , wherein
 the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first protruding portions (P 1 ) and a plurality of second recessing portions (R 2 ) which farm a jagged shape and are matched in form of concave-convex, or   the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first recessing portions (R 1 ) and a plurality of second protruding portions (P 2 ) which form a jagged shape and are matched in form of concave-convex, or   the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first protruding portions (P 1 ) and a plurality of second protruding portions (P 2 ) which form a jagged shape and are matched in clearance fit, or   the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first recessing portions (R 1 ) and a plurality of second recessing portions (R 2 ) which form a jagged shape and are matched in clearance fit.   
     
     
       7. The cell according to  claim 6 , wherein
 the first electrode tab ( 3 ) and the first protruding portion (P 1 ) or the first recessing portion (R 1 ) provided on the first electrode tab ( 3 ) are integrally formed;   the second electrode tab ( 4 ) and the second protruding portion (P 2 ) or the second recessing portion (R 2 ) provided on the second electrode tab ( 4 ) are integrally formed.   
     
     
       8. The cell according to  claim 6 , wherein a shape of the first protruding portion (P 1 ), a shape of the first recessing portion (R 1 ), a shape of the second protruding portion (P 2 ), a shape of the second recessing portion (R 2 ) each are one of a rectangle, a square, a triangle, a semicircle, a trapezoid, a polygon with more than four sides. 
     
     
       9. The cell according to  claim 1 , wherein at least one of the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) is flat. 
     
     
       10. An electrochemical device, comprising:
 a cell, comprising:
 a first electrode plate ( 1 ) comprising a first current collector ( 11 ) and a first active material layer ( 12 ) which is selectively provided on a surface (S 11 ) of the first current collector ( 11 ) and contains a first active material; 
 a second electrode plate ( 2 ) opposite to the first electrode plate ( 1 ) in electric polarity, comprising a second current collector ( 21 ) and a second active material layer ( 22 ) which is selectively provided on a surface (S 21 ) of the second current collector ( 21 ) and contains a second active material; 
 a first electrode tab ( 3 ) provided and electrically connected to the first current collector ( 11 ) of the first electrode plate ( 1 ); 
 a second electrode tab ( 4 ) provided and electrically connected to the second current collector ( 21 ) of the second electrode plate ( 2 ); and 
 a separator ( 5 ) provided between the first electrode plate ( 1 ) and the second electrode plate ( 2 ); 
 the surface (S 11 ) of the first current collector ( 11 ) having a part which is not provided with the first active material layer ( 12 ) thereon and this part being defined as a first surface uncoated region (B 11 ); 
 the surface (S 21 ) of the second current collector ( 21 ) having a part which is not provided with the second active material layer ( 22 ) thereon and this part being defined as a second surface uncoated region (B 21 ); 
 the first electrode tab ( 3 ) being provided on the first surface uncoated region (B 11 ) and the second electrode tab ( 4 ) being provided on the second surface uncoated region (B 21 ); 
 the first electrode tab ( 3 ) extending toward two opposite transverse edges (TE 11 ) of the first surface uncoated region (B 11 ) along a width direction (W) and one side edge ( 31 ) positioned outside in the width direction (W) being close to one corresponding transverse edge (TE 11 ) of the first surface uncoated region (B 11 ), and the first electrode tab ( 3 ) extending toward two opposite longitudinal edges (LE i 1 ) of the first surface uncoated region (B 11 ) along a length direction (L) and two outer side edges ( 32 ) in the length direction (L) being close to the two longitudinal edges (LE 11 ) of the first surface uncoated region (B 11 ), respectively; and/or the second electrode tab ( 4 ) extending toward two opposite transverse edges (TE 21 ) of the second surface uncoated region (B 21 ) along the width direction (W) and one side edge ( 41 ) positioned outside in the width direction (W) being close to one corresponding transverse edge (TE 21 ) of the second surface uncoated region (B 21 ), and the second electrode tab ( 4 ) extending toward two opposite longitudinal edges (LE 21 ) of the second surface uncoated region (B 21 ) along the length direction (L) and two outer side edges ( 42 ) in the length direction (L) being close to the two longitudinal edges (LE 21 ) of the second surface uncoated region (B 21 ), respectively; 
 the first electrode tab ( 3 ) and the second electrode tab ( 4 ) being spaced apart from each other in the width direction (W), and the separator ( 5 ) being presented between the first electrode tab ( 3 ) and the second electrode tab ( 4 ); 
 when the cell is subjected to a mechanical shock, the first electrode tab ( 3 ) and the second electrode tab ( 4 ) being deformed to puncture the separator ( 5 ) between the first electrode tab ( 3 ) and the second electrode tab ( 4 ) such that the first current collector ( 11 ) and the second current collector ( 21 ) being electrically connected. 
   
     
     
       11. The electrochemical device according to  claim 10 , wherein
 the first electrode tab ( 3 ) is welded to the first current collector ( 11 ) of the first electrode plate ( 1 ) or is formed by cutting the first current collector ( 11 ) of the first electrode plate ( 1 ); and/or   the second electrode tab ( 4 ) is welded to the second current collector ( 21 ) of the second electrode plate ( 2 ) or is formed by cutting the second current collector ( 21 ) of the second electrode plate ( 2 ).   
     
     
       12. The electrochemical device according to  claim 10 , wherein
 the first electrode tab ( 3 ) and the second electrode tab ( 4 ) each have a thickness of TT, and 5 μm≤TT≤100 μm;   the first electrode tab ( 3 ) and the second electrode tab ( 4 ) each have a length of LT, and 10 mm≤LT≤500 mm;   the first electrode tab ( 3 ) and the second electrode tab ( 4 ) each have a width of WT, and 2 mm≤WT≤250 mm.   
     
     
       13. The electrochemical device according to  claim 10 , wherein
 a minimum distance between the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned outside in the width direction (W) and the one corresponding transverse edge (TE 11 ) of the first surface uncoated region (B 11 ) is 3 mm;   a minimum distance between the each outer side edge ( 32 ) of the first electrode tab ( 3 ) in the length direction (L) and the one corresponding longitudinal edge (LE 11 ) of the first surface uncoated region (B 11 ) is 3 mm;   a minimum distance between the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned outside in the width direction (W) and the one corresponding transverse edge (TE 21 ) of the second surface uncoated region (B 21 ) is 3 mm;   a minimum distance between the each outer side edge ( 42 ) of the second electrode tab ( 4 ) in the length direction (L) and the one corresponding longitudinal edge (LE 21 ) of the second surface uncoated region (B 21 ) is 3 mm.   
     
     
       14. The electrochemical device according to  claim 10 , wherein a distance between the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) is 1 mm˜5 mm in the width direction (W). 
     
     
       15. The electrochemical device according to  claim 10 , wherein
 the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first protruding portions (P 1 ) and a plurality of second recessing portions (R 2 ) which form a jagged shape and are matched in form of concave-convex, or   the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first recessing portions (R 1 ) and a plurality of second protruding portions (P 2 ) which form a jagged shape and are matched in form of concave-convex, or   the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first protruding portions (P 1 ) and a plurality of second protruding portions (P 2 ) which form a jagged shape and are matched in clearance fit, or   the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) are respectively provided with a plurality of first recessing portions (R 1 ) and a plurality of second recessing portions (R 2 ) which form a jagged shape and are matched in clearance fit.   
     
     
       16. The electrochemical device according to  claim 15 , wherein
 the first electrode tab ( 3 ) and the first protruding portion (P 1 ) or the first recessing portion (R 1 ) provided on the first electrode tab ( 3 ) are integrally formed;   the second electrode tab ( 4 ) and the second protruding portion (P 2 ) or the second recessing portion (R 2 ) provided on the second electrode tab ( 4 ) are integrally formed.   
     
     
       17. The electrochemical device according to  claim 15 , wherein a shape of the protruding portion (P 1 ), a shape of the first recessing portion (R 1 ), a shape of the second protruding portion (P 2 ), a shape of the second recessing portion (R 2 ) each are one of a rectangle, a square, a triangle, a semicircle, a trapezoid, a polygon with more than four sides. 
     
     
       18. The electrochemical device according to  claim 10 , wherein at least one of the one side edge ( 31 ) of the first electrode tab ( 3 ) positioned inside in the width direction (W) and the one side edge ( 41 ) of the second electrode tab ( 4 ) positioned inside in the width direction (W) is flat. 
     
     
       19. A cell, comprising:
 a first electrode plate, comprising a first current collector and a first active material layer, the first active material layer is provided on a surface of the first current collector;   a second electrode plate, opposite to the first electrode plate in electric polarity, the second electrode plate comprises a second current collector and a second active material layer, the second active material layer is provided on a surface of the second current collector;   a first electrode tab, provided and electrically connected to the first current collector;   a second electrode tab, provided and electrically connected to the second current collector;   a separator, provided between the first electrode plate and the second electrode plate;   wherein   the first current collector has a first surface uncoated region;   the second current collector has a second surface uncoated region;   the first electrode tab is provided on the first surface uncoated region, and the second electrode tab is provided on the second surface uncoated region;   the first electrode tab extends toward two opposite transverse edges of the first surface uncoated region along a width direction, and further extends toward two opposite longitudinal edges of the first surface uncoated region along a length direction;   the second electrode tab extends toward two opposite transverse edges of the second surface uncoated region along the width direction, and further extends toward two opposite longitudinal edges of the second surface uncoated region along the length direction;   the first electrode tab and the second electrode tab are spaced apart from each other in the width direction, and the separator is presented between the first electrode tab and the second electrode tab; and   a distance between the first electrode tab and the second electrode tab in the width direction is 1 mm to 5 mm.    
     
     
       20. The cell according to claim 19, wherein
 the first electrode tab is welded to the first current collector or formed by cutting the first current collector;   the second electrode tab is welded to the second current collector or formed by cutting the second current collector.    
     
     
       21. The cell according to claim 19, wherein
 each of the first electrode tab and the second electrode tab has a thickness of TT, 5 μm≤TT≤100 μm;   each of the first electrode tab and the second electrode tab has a length of LT, 10 mm≤LT≤500 mm;   each of the first electrode tab and the second electrode tab has a width of WT, 2 mm≤WT≤250 mm.    
     
     
       22. The cell according to claim 19, wherein
 a minimum distance between a first side edge of the first electrode tab in the width direction and the corresponding transverse edge of the first surface uncoated region is 3 mm;   a minimum distance between a second side edge of the first electrode tab in the length direction and the corresponding longitudinal edge of the first surface uncoated region is 3 mm;   a minimum distance between a first side edge of the second electrode tab in the width direction and the corresponding transverse edge of the second surface uncoated region is 3 mm;   a minimum distance between a second side edge of the second electrode tab in the length direction and the corresponding longitudinal edge of the second surface uncoated region is 3 mm.    
     
     
       23. The cell according to claim 19, wherein
 a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with a plurality of first protruding portions and a plurality of second recessing portions, the plurality of first protruding portions and the plurality of second recessing portions form a jagged shape matching in form of concave-convex; or   a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with a plurality of first recessing portions and a plurality of second protruding portions, the plurality of first recessing portions and the plurality of second protruding portions form a jagged shape matching in form of concave-convex; or   a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with the plurality of first protruding portions and the plurality of second protruding portions, the plurality of first protruding portions and the plurality of second protruding portions form a jagged shape matching in clearance fit; or   a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with the plurality of first recessing portions and the plurality of second recessing portions, the plurality of first recessing portions and the plurality of second recessing portions form a jagged shape matching in clearance fit.    
     
     
       24. The cell according to claim 23, wherein
 the first electrode tab and the plurality of first protruding portions or the plurality of first recessing portions provided on the first electrode tab are integrally formed; and   the second electrode tab and the plurality of second protruding portions or the plurality of second recessing portions provided on the second electrode tab are integrally formed.    
     
     
       25. The cell according to claim 24, wherein
 the first protruding portion, the first recessing portion, the second protruding portion and the second recessing portion are respectively in a shape of rectangle, square, triangle, semicircle, trapezoid or polygon with more than four sides.    
     
     
       26. The cell according to claim 19, wherein
 at least one of a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction is flat.    
     
     
       27. An electrochemical device, comprising:
 a cell, comprising:   a first electrode plate, comprising a first current collector and a first active material layer, the first active material layer is provided on a surface of the first current collector;   a second electrode plate, opposite to the first electrode plate in electric polarity, the second electrode plate comprises a second current collector and a second active material layer, the second electrode material layer is provided on a surface of the second current collector;   a first electrode tab, provided and electrically connected to the first current collector;   a second electrode tab, provided and electrically connected to the second current collector;   a separator, provided between the first electrode plate and the second electrode plate;   wherein   the first current collector has a first surface uncoated region;   the second current collector has a second surface uncoated region;   the first electrode tab is provided on the first surface uncoated region and the second electrode tab is provided on the second surface uncoated region;   the first electrode tab extends toward two opposite transverse edges of the first surface uncoated region along a width direction, and further extends toward two opposite longitudinal edges of the first surface uncoated region along a length direction;   the second electrode tab extends toward two opposite transverse edges of the second surface uncoated region along the width direction, and further extends toward two opposite longitudinal edges of the second surface uncoated region along the length direction;   the first electrode tab and the second electrode tab are spaced apart from each other in the width direction, and the separator is presented between the first electrode tab and the second electrode tab; and   a distance between the first electrode tab and the second electrode tab in the width direction is 1 mm to 5 mm.    
     
     
       28. The electrochemical device according to claim 27, wherein
 the first electrode tab is welded to the first current collector or formed by cutting the first current collector;   the second electrode tab is welded to the second current collector or formed by cutting the second current collector.    
     
     
       29. The electrochemical device according to claim 27, wherein
 each of the first electrode tab and the second electrode tab has a thickness of TT, 5 μm≤TT≤100 μm;   each of the first electrode tab and the second electrode tab has a length of LT, 10 mm≤LT≤500 mm;   each of the first electrode tab and the second electrode tab has a width of WT, 2 mm≤WT≤250 mm.    
     
     
       30. The electrochemical device according to claim 27, wherein
 a minimum distance between a first side edge of the first electrode tab in the width direction and the corresponding transverse edge of the first surface uncoated region is 3 mm;   a minimum distance between a second side edge of the first electrode tab in the length direction and the corresponding longitudinal edge of the first surface uncoated region is 3 mm;   a minimum distance between a first side edge of the second electrode tab in the width direction and the corresponding transverse edge of the second surface uncoated region is 3 mm;   a minimum distance between a second side edge of the second electrode tab in the length direction and the corresponding longitudinal edge of the second surface uncoated region is 3 mm.    
     
     
       31. The electrochemical device according to claim 27, wherein
 a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with a plurality of first protruding portions and a plurality of second recessing portions, the plurality of first protruding portions and the plurality of second recessing portions form a jagged shape matching in form of concave-convex; or   a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with a plurality of first recessing portions and a plurality of second protruding portions, the plurality of first recessing portions and the plurality of second protruding portions form a jagged shape matching in form of concave-convex; or   a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with the plurality of first protruding portions and the plurality of second protruding portions, the plurality of first protruding portions and the plurality of second protruding portions form a jagged shape matching in clearance fit; or   a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction are respectively provided with the plurality of first recessing portions and the plurality of second recessing portions, the plurality of first protruding portions and the plurality of second protruding portions form a jagged shape matching in clearance fit.    
     
     
       32. The electrochemical device according to claim 31, wherein
 the first electrode tab and the plurality of first protruding portions or the plurality of first recessing portions provided on the first electrode tab are integrally formed; and   the second electrode tab and the plurality of second protruding portions or the plurality of second recessing portions provided on the second electrode tab are integrally formed.    
     
     
       33. The electrochemical device according to claim 31, wherein
 the first protruding portion, the first recessing portion, the second protruding portion and the second recessing portion are respectively in a shape of rectangle, square, triangle, semicircle, trapezoid, or polygon with more than four sides.    
     
     
       34. The electrochemical device according to claim 27, wherein
 at least one of a first side edge of the first electrode tab in the width direction and a first side edge of the second electrode tab in the width direction is flat.    
     
     
       35. The cell according to claim 19, wherein
 a first side edge of the first electrode tab in the width direction is close to the corresponding transverse edge of the first surface uncoated region, and two second side edges of the first electrode tab in the length direction are close to the two longitudinal edges of the first surface uncoated region;   a first side edge of the second electrode tab in the width direction is close to one corresponding transverse edge of the second surface uncoated region, and two second side edges of the second electrode tab in the length direction are close to the two longitudinal edges of the second surface uncoated region.    
     
     
       36. The electrochemical device according to claim 27, wherein
 a first side edge of the first electrode tab in the width direction is close to the corresponding transverse edge of the first surface uncoated region, and two second side edges of the first electrode tab in the length direction are close to the two longitudinal edges of the first surface uncoated region;   a first side edge of the second electrode tab in the width direction is close to one corresponding transverse edge of the second surface uncoated region, and two second side edges of the second electrode tab in the length direction are close to the two longitudinal edges of the second surface uncoated region.