Electrochemical apparatus, preparation method thereof, and electronic apparatus
An electrochemical apparatus includes an electrode assembly, where the electrode assembly includes a positive electrode plate, a negative electrode plate, and a separator. The separator is disposed between the positive electrode plate and the negative electrode plate. The positive electrode plate, the negative electrode plate, and the separator are made into the electrode assembly through winding. The electrochemical apparatus further includes a first bonding member. The positive electrode plate includes a first starting section. A first end of the first bonding member is bonded to the first starting section, and a second end of the first bonding member is bonded to the separator.
1 . An electrochemical apparatus, comprising an electrode assembly, wherein the electrode assembly comprises a positive electrode plate, a negative electrode plate and a separator; the separator is disposed between the positive electrode plate and the negative electrode plate; and the positive electrode plate, the negative electrode plate, and the separator are wound to form the electrode assembly;
the electrochemical apparatus further comprises a first bonding member, a winding starting layer of the positive electrode plate comprises a first starting section, a first end of the first bonding member is bonded to the first starting section; and
a winding starting layer of the separator comprises a first straight portion and a first bent portion, wherein the first straight portion and the first bent portion are connected to each other, a winding starting layer of the negative electrode plate comprises a second starting section, an end of the second starting section is located at a side of the first bent portion, and a second end of the first bonding member is bonded to a side of the first bent portion facing away from the second starting section.
2 . The electrochemical apparatus according to claim 1 , wherein in a first direction, the first bent portion exceeds an end of the first starting section; in the first direction, a width of the electrode assembly is W 1 , a length of a portion of the first bonding member that covers the first starting section is L 1 , and a length of a portion of the first bonding member that does not cover the first starting section is L 2 ; in a second direction, a thickness of the electrode assembly is T 1 ; and the second direction is perpendicular to the first direction; wherein (W 1 −T 1 )/10<(L 1 +L 2 )/2< (W 1 −T 1 )/2.
3 . The electrochemical apparatus according to claim 2 , wherein in the first direction, a distance between the end of the first starting section and an end of the first bent portion is L 3 , wherein 0 mm<L 3 ≤10 mm.
4 . The electrochemical apparatus according to claim 2 , wherein in the first direction, a length of the first starting section is L 4 , and a length of the second starting section is L 5 , wherein L 4 −L 1 ≤L 5 .
5 . The electrochemical apparatus according to claim 1 , wherein the first bonding member comprises a substrate layer and a first bonding layer, the substrate layer comprises a first surface and a second surface opposite to the first surface, the first bonding layer is disposed on the first surface, and the first bonding layer is bonded to the first starting section and the separator.
6 . The electrochemical apparatus according to claim 5 , wherein the first bonding member is bent, and the first bonding layer of the first end and the first bonding layer of the second end are disposed toward a same side of the substrate layer.
7 . The electrochemical apparatus according to claim 5 , wherein the first bonding member is bent, and the first bonding layer of the first end and the first bonding layer of the second end are disposed facing opposite directions separately.
8 . The electrochemical apparatus according to claim 5 , wherein the first bonding member further comprises a second bonding layer, the second bonding layer is disposed on the second surface of the substrate layer, the first bonding member covers the end of the first starting section, the first bonding layer is bonded to the separator, and the second bonding layer is bonded to two opposite side surfaces of the first starting section.
9 . The electrochemical apparatus according to claim 1 , wherein the electrochemical apparatus further comprises a tab, the tab is connected to the electrode assembly; and in a second direction, a projection of the first bonding member and a projection of the tab on a surface of the electrode assembly do not overlap.
10 . The electrochemical apparatus according to claim 1 , wherein in a third direction, a side edge of the first bonding member exceeds a side edge of the positive electrode plate; and on a same side edge, a distance between the side edge of the first bonding member and the side edge of the positive electrode plate is 0 mm-10 mm.
11 . The electrochemical apparatus according to claim 9 , wherein the electrochemical apparatus further comprises a second bonding member, the separator is on an outermost ring of the electrode assembly, and the second bonding member is disposed at a terminating end of the separator.
12 . The electrochemical apparatus according to claim 11 , wherein in the second direction, a projection of the second bonding member and the projection of the tab on the surface of the electrode assembly do not overlap.
13 . The electrochemical apparatus according to claim 5 , wherein a thickness of the first bonding member is 3 μm-100 μm; a material of the substrate layer comprises one or more of polyolefin, polyacrylonitrile, polyol ester, polyamide, polyurethane, or a compound thereof; and a material of the first bonding layer comprises one or more of polyolefin, polyurethane, polyacrylate, organosilicone, rubber, or a compound thereof.
14 . The electrochemical apparatus according to claim 13 , wherein the first bonding layer is configured to bond the first starting section and the separator during use.
15 . The electrochemical apparatus according to claim 1 , wherein an edge of the first bonding member is neat.
16 . A preparation method of an electrochemical apparatus, the preparation method comprises:
preparing a first bonding layer to bond a first bonding member to a winding starting end of a positive electrode plate;
stacking the positive electrode plate, a negative electrode plate, and a separator, wherein a first end of the first bonding member is bonded to the positive electrode plate, and a second end of the first bonding member is bonded to the separator; and
winding the positive electrode plate, the negative electrode plate, and the separator that are stacked, wherein the separator is disposed between the positive electrode plate and the negative electrode plate;
wherein a winding starting layer of the separator comprises a first straight portion and a first bent portion, wherein the first straight portion and the first bent portion are connected to each other, a winding starting layer of the negative electrode plate comprises a second starting section, an end of the second starting section is located at a side of the first bent portion, and a second end of the first bonding member is bonded to a side of the first bent portion facing away from the second starting section.
17 . An electronic apparatus, comprising an electrochemical apparatus, the electrochemical apparatus comprising an electrode assembly, wherein the electrode assembly comprises a positive electrode plate, a negative electrode plate and a separator; the separator is disposed between the positive electrode plate and the negative electrode plate; and the positive electrode plate, the negative electrode plate and the separator are wound to form the electrode assembly;
the electrochemical apparatus further comprises a first bonding member, a winding starting layer of the positive electrode plate comprises a first starting section, a first end of the first bonding member is bonded to the first starting section; and
a winding starting layer of the separator comprises a first straight portion and a first bent portion, wherein the first straight portion and the first bent portion are connected to each other, a winding starting layer of the negative electrode plate comprises a second starting section, an end of the second starting section is located at a side of the first bent portion, and a second end of the first bonding member is bonded to a side of the first bent portion facing away from the second starting section.
18 . The electronic apparatus according to claim 17 , wherein a winding starting layer of the separator comprises a first straight portion and a first bent portion connected to the first straight portion, the negative electrode plate comprises a second starting section, an end of the second starting section is located at a side of the first bent portion, and the second end of the first bonding member is bonded to a side of the first bent portion facing away from the second starting section.
19 . The electronic apparatus according to claim 18 , wherein in a first direction, the first bent portion exceeds an end of the first starting section; in the first direction, a width of the electrode assembly is W 1 , a length of a portion of the first bonding member that covers the first starting section is L 1 , and a length of a portion of the first bonding member that does not cover the first starting section is L 2 ; in a second direction, a thickness of the electrode assembly is T; and the second direction is perpendicular to the first direction; wherein (W 1 −T 1 )/10<(L 1 +L 2 )/2<(W 1 −T 1 )/2.