Electrode assembly, battery cell, battery, and electric apparatus
An electrode assembly includes a first electrode plate and a second electrode plate. The first electrode plate includes a first body portion and a tab. The first body portion has a first end portion in a first direction. The tab is coupled to the first end portion. The second electrode plate includes a second body portion and an insulation portion coupled to the second body portion. The first body portion and the second body portion are stacked in a stacking direction perpendicular to the first direction. The second body portion has a second end portion close to the tab in the first direction. The insulation portion covers at least part of the second end portion so as to separate the tab from the second end portion when the tab is bent.
1 . An electrode assembly, comprising:
a first electrode plate comprising a first body portion, a first tab, and a first insulation portion, the first body portion having a first end portion in a first direction, the first tab being coupled to the first end portion, the first body portion comprising a first current collection zone, a first active material layer, and a protective layer, the first active material layer being applied on a surface of the first current collection zone, the protective layer being applied on a surface of the first current collection zone and coupled to the first active material layer, a first surface of the protective layer parallel to the first direction and away from the first current collection zone being coplanar with a second surface of the first active material layer parallel to the first direction and away from the first current collection zone, and the first surface and the second surface not overlapping with each other in a stacking direction perpendicular to the first direction;
a second electrode plate comprising a second body portion, a second tab, and a second insulation portion coupled to the second body portion, the first body portion and the second body portion being stacked in the stacking direction perpendicular to the first direction, the second body portion having a second end portion located at a same side as the first tab in the first direction, and the second insulation portion covering at least part of the second end portion; and
a separator configured to separate the first electrode plate and the second electrode plate;
wherein:
the first insulation portion comprises a first coverage zone and a first connection zone coupled to the first coverage zone, the first coverage zone is disposed on a side of the first body portion in the first direction and covers an end surface of the protective layer, and the first connection zone is fixed to the protective layer;
the second insulation portion comprises a second coverage zone and a second connection zone coupled to the second coverage zone, the second coverage zone is disposed on a side of the second body portion in the first direction and covers at least part of the second end portion;
the second body portion comprises a second current collection zone and a second active material layer, the second active material layer is applied on a surface of the second current collection zone;
the second coverage zone is located between the second tab and the second current collection zone; and
the second connection zone is connected to the second body portion, and a ratio of a size of the second connection zone in the first direction to a size of the second body portion in the first direction ranges from 0.5% to 6%.
2 . The electrode assembly according to claim 1 , wherein:
the second connection zone is at least partially located between the first body portion and the second body portion so as to separate the second body portion from the first tab when the first tab is inserted between the first body portion and the second body portion.
3 . The electrode assembly according to claim 2 , wherein the second connection zone is one of two second connection zones of the second insulation portion, and the two second connection zones are disposed on two sides of the second body portion in the stacking direction, respectively.
4 . The electrode assembly according to claim 2 , wherein:
the first connection zone is at least partially located between the first body portion and the second body portion and is connected to the first body portion.
5 . The electrode assembly according to claim 4 , wherein:
the first body portion further has a third end portion in the first direction farther away from the first end portion, and the second body portion further has a fourth end portion in the first direction farther away from the second end portion; and
the second tab is coupled to the second end portion or the fourth end portion.
6 . The electrode assembly according to claim 5 , wherein:
the first electrode plate further comprises a third insulation portion, the third insulation portion being coupled to the first body portion and covering at least part of the third end portion.
7 . The electrode assembly according to claim 5 , wherein:
the second electrode plate further comprises a third insulation portion, the third insulation portion being coupled to the second body portion and covering at least part of the fourth end portion.
8 . The electrode assembly according to claim 4 , wherein in a direction pointing away from the first tab and parallel to the first direction, an edge of the second connection zone farther away from the second coverage zone does not exceed an edge of the first connection zone farther away from the first coverage zone.
9 . The electrode assembly according to claim 8 , wherein in the direction pointing away from the first tab and parallel to the first direction, a gap between the edge of the second connection zone farther away from the second coverage zone and the edge of the first connection zone farther away from the first coverage zone is greater than 0.05 mm.
10 . The electrode assembly according to claim 1 , wherein the second insulation portion has a porous structure for metal ions to pass through.
11 . The electrode assembly according to claim 1 , wherein a thickness of the second insulation portion is greater than a thickness of the separator.
12 . The electrode assembly according to claim 1 , wherein:
in a direction pointing away from the first tab and parallel to the first direction, an edge of the first connection zone farther away from the first tab is coplanar with an edge of the protective layer father away from the first tab.
13 . The electrode assembly according to claim 1 , wherein:
the protective layer comprises a binder and an insulation material, and the insulation material comprises at least one of aluminum oxide or aluminum hydroxide oxide.
14 . The electrode assembly according to claim 1 , wherein:
a thickness of the second insulation portion is in a range of 0.005 mm to 0.2 mm.
15 . The electrode assembly according to claim 1 , wherein:
the protective layer only covers an end of the second active material layer in the first direction, the protective layer is not in contact with the first tab.
16 . A battery cell, comprising:
a housing with an accommodating cavity and an opening;
an electrode assembly accommodated in the accommodating cavity and comprising:
a first electrode plate comprising a first body portion, a first tab, and a first insulation portion, the first body portion having a first end portion in a first direction, the first tab being coupled to the first end portion, the first body portion comprising a first current collection zone, a first active material layer, and a protective layer, the first active material layer being applied on a surface of the first current collection zone, the protective layer being applied on a surface of the first current collection zone and coupled to the first active material layer, a first surface of the protective layer parallel to the first direction and away from the first current collection zone being coplanar with a second surface of the first active material layer parallel to the first direction and away from the first current collection zone, and the first surface and the second surface not overlapping with each other in a stacking direction perpendicular to the first direction;
a second electrode plate comprising a second body portion, a second tab, and a second insulation portion coupled to the second body portion, the first body portion and the second body portion being stacked in the stacking direction perpendicular to the first direction, the second body portion having a second end portion located at a same side as the first tab in the first direction, and the second insulation portion covering at least part of the second end portion; and
a separator configured to separate the first electrode plate and the second electrode plate; and
a cover plate configured to close the opening of the housing;
wherein:
the first insulation portion comprises a first coverage zone and a first connection zone coupled to the first coverage zone, the first coverage zone is disposed on a side of the first body portion in the first direction and covers an end surface of the protective layer, and the first connection zone is fixed to the protective layer;
the second insulation portion comprises a second coverage zone and a second connection zone coupled to the second coverage zone, the second coverage zone is disposed on a side of the second body portion in the first direction and covers at least part of the second end portion;
the second body portion comprises a second current collection zone and a second active material layer, the second active material layer is applied on a surface of the second current collection zone;
the second coverage zone is located between the second tab and the second current collection zone; and
the second connection zone is connected to the second body portion, and a ratio of a size of the second connection zone in the first direction to a size of the second body portion in the first direction ranges from 0.5% to 6%.
17 . The battery cell according to claim 16 , wherein:
the second connection zone is at least partially located between the first body portion and the second body portion so as to separate the second body portion from the first tab when the first tab is inserted between the first body portion and the second body portion.
18 . A battery, comprising:
a box body; and
the battery cell according to claim 16 and accommodated in the box body.
19 . An electric apparatus, comprising the battery according to claim 18 , the battery being configured to provide power to the electric apparatus.
20 . An electrode assembly, comprising:
a first electrode plate comprising a first body portion and a first tab, the first body portion having a first end portion in a first direction, and the first tab being coupled to the first end portion, the first body portion comprising a first current collection zone, a first active material layer, and a protective layer, the first active material layer being applied on a surface of the first current collection zone, the protective layer being applied on a surface of the first current collection zone and coupled to the first active material layer, the protective layer comprising a binder and an insulation material, and the insulation material comprising aluminum hydroxide oxide;
a second electrode plate comprising a second body portion, a second tab, and an insulation portion coupled to the second body portion, the first body portion and the second body portion being stacked in a stacking direction perpendicular to the first direction, the second body portion having a second end portion located at a same side as the first tab in the first direction, and the insulation portion covering at least part of the second end portion; and
a separator configured to separate the first electrode plate and the second electrode plate;
wherein:
the insulation portion comprises a coverage zone and a connection zone coupled to the coverage zone, the coverage zone is disposed on a side of the second body portion in the first direction and covers at least part of the second end portion;
the second body portion comprises a second current collection zone and a second active material layer, the second active material layer is applied on a surface of the second current collection zone;
the coverage zone is located between the second tab and the second current collection zone; and
the connection zone is connected to the second body portion, and a ratio of a size of the connection zone in the first direction to a size of the second body portion in the first direction ranges from 0.5% to 6%.