Amperex Technology Limited

A secondary battery includes a non-aqueous electrolyte. The non-aqueous electrolyte includes: fluoroethyl propionate, where the fluoroethyl propionate is selected from the group consisting of 2,2-difluoroethyl propanoate, 2,2,2-trifluoroethyl propionate, and a combination thereof, and based on a total mass of the non-aqueous electrolyte, a mass percentage of the fluoroethyl propionate is 5% to 65%; and ethylene carbonate (EC) and propylene carbonate (PC), where based on the total mass of the non-aqueous electrolyte, the sum of the mass percentages of the ethylene carbonate (EC) and the propylene carbonate (PC) is less than or equal to 15%.

An electrochemical device and an electronic device. A packaging bag of the electrochemical device includes a main portion and a top seal portion connected together. A sealed region of the top seal portion includes an edge point Q2 close to an edge of the cell assembly and located on a first wall. The top seal portion includes the first wall extending along a first direction. A second wall of the main portion is connected to the first wall and a third wall. A connection point Q3 is formed at a junction between the second wall and the third wall. An angle R between the first wall and a straight line K1 satisfies: 80° ≤ R ≤ 110°; and/or along the first direction, a distance h between the edge point Q2 and the connection point Q3 satisfies: 0 mm ≤ h ≤ 1 mm.

The present application discloses a secondary battery and an electronic apparatus. The secondary battery includes a first shell, a second shell, and an electrode assembly. The first shell includes a first portion and a second portion, where the second portion surrounds an edge of the first portion. The second shell includes a third portion and a fourth portion, where the fourth portion surrounds an edge of the third portion; the second shell and the first shell are assembled together, and the second shell is insulatedly connected to the first shell. The electrode assembly includes a plurality of first electrode plates and a plurality of second electrode plates, where an outermost first electrode plate of the electrode assembly is a first sub-electrode plate; an outermost second electrode plate of the electrode assembly is a second sub-electrode plate. The first sub-electrode plate includes a first current collector, where the first current collector has a first surface and a second surface opposite to each other, and the first surface is electrically connected to the first portion; the second sub-electrode plate includes a second current collector, where the second current collector has a third surface and a fourth surface opposite to each other, and the third surface is electrically connected to the third portion. This solution is advantageous for reducing the dimension of the secondary battery and increasing the volumetric energy density of the secondary battery.

A secondary battery, in which an outermost electrode plate of an electrode assembly is a first single-sided positive electrode plate. The first single-sided positive electrode plate includes a first positive electrode coating facing the first negative electrode plate, and a capacity of the first positive electrode coating is C<11>. The first negative electrode plate includes a first negative electrode coating facing the first positive electrode coating, and a capacity of the first negative electrode coating is C<21>. The first inner positive electrode plate includes a first inner positive electrode coating facing the first inner negative electrode plate, and a capacity of the first inner positive electrode coating is C<31>. The first inner negative electrode plate includes a first inner negative electrode coating facing the first inner positive electrode coating, and a capacity of the first inner negative electrode coating is C<41>, satisfying: 1 < (C<21>/C<11>)/(C<41>/C<31>) < 1.12.

An electrode plate composite (10) includes a negative electrode plate (11), a first separator (12), a second separator (13), and a plurality of positive electrode plates (14). The negative electrode plate (11) includes a first current collector (111), a first active material layer (112), and a second active material layer (113). The first current collector (111) includes a first surface (1111) and a second surface (1112) arranged opposite to each other along a first direction (X). The first active material layer (112) is disposed on the first surface (1111), and the second active material layer (113) is disposed on the second surface (1112). The plurality of positive electrode plates (14) are alternately laminated on the first separator (12) and the second separator (13), and projections of the plurality of positive electrode plates (14) along the first direction (X) do not overlap.

A secondary battery (100) includes an electrode assembly (20) with a wound structure, and the electrode assembly (20) includes a first electrode plate (21). The first electrode plate (21) includes a first current collector (211) and a first active material layer (212), and the first current collector (211) includes a first surface (211A) and a second surface (211B). The first current collector (211) includes a first section (2111) and a second section (2112), where the first surface (211A) and the second surface (211B) of the first section (2111) are both provided with the first active material layer (212), the second surface (211B) of the second section (2112) is provided with the first active material layer (212), and the first surface (211A) of the second section (2112) is not provided with an active material layer. A position where the first section (2111) and the second section (2112) meet is defined as a boundary line (101), and the first electrode plate (21) corresponding to the first section (2111) includes a first region (213), where the first region (213) is a region extending by a distance L₁ from the boundary line (101) along a direction from the second section (2112) toward the first section (2111), and 0.5 mm ≤ L₁ ≤ 5 mm. The first current collector (211) in the first region (213) is a first sub-section (2111A), the first active material layer (212) on the first surface (211A) of the first sub-section (2111A) is a first portion (212A), and at least one recess (102) is provided on the first portion (212A).

A secondary battery includes an electrode assembly having a winding structure and an electrolyte. The electrode assembly includes a positive electrode, a separator, and a negative electrode, where the positive electrode and the negative electrode each include a current collector and a material layer disposed on at least one surface of the current collector. The negative electrode material layer extends beyond the positive electrode material layer in a winding direction, the extended region is a first region, a length of the first region is L mm, a length of the negative electrode material layer is L₀ mm, and 0.8% ≤ L/L₀ ≤ 18%. The electrolyte includes 1,3-propanesultone, and based on total mass of the electrolyte, a mass content of the 1,3-propanesultone is A%, where 0.01 ≤ A ≤ 8.

This application provides a cylindrical battery and an electric device. The cylindrical battery includes an electrode assembly and an adhesive tape. The electrode assembly is a wound structure and has a winding central axis. The electrode assembly includes a first electrode sheet and a first tab. An outermost turn of the first electrode sheet is connected to the first tab. The first electrode sheet is provided with a winding tail end. The adhesive tape includes a first portion and a second portion. The first portion is attached to the first electrode sheet. The second portion is attached to the first tab. Along a winding direction of the electrode assembly, the second portion includes a first side and a second side that are oppositely disposed. The second side is closer to the winding tail end than the first side. The first portion is located on the first side. When viewed from an extension direction of the winding central axis, a line connecting a winding center and one end of the first portion close to the second portion is defined as a first virtual line, a line connecting the winding center and one end of the first portion away from the second portion is defined as a second virtual line, and an angle between the first virtual line and the second virtual line is not less than 10°, reducing a possibility of fracture at a welding edge.

A battery cell, including an electrode assembly and a packaging bag, where the electrode assembly includes a tab, the packaging bag is configured to accommodate the electrode assembly, a sealing zone is formed on a periphery of the packaging bag, one end of the tab is electrically connected to a body of the electrode assembly, and the other end of the tab protrudes out of the sealing zone; the sealing zone is provided with a weak zone, and in a predetermined temperature range, a packaging tension of the weak zone in the packaging bag reduces to release gas inside the battery cell to the outside of the battery cell. This application further discloses an electronic apparatus, including a battery, where the battery includes a battery cell and a housing accommodating the battery cell, and the battery cell includes the foregoing battery cell.

A secondary battery includes a housing and an electrode assembly. The housing includes a packaging film. The packaging film is wrapped around to enclose the electrode assembly. The housing further includes an adhesive layer. The packaging film is coated with the adhesive layer on a surface facing away from the electrode assembly. The adhesive layer includes a resin compound. A tensile elongation at break of the packaging film is φ₁, and a tensile elongation at break of a part of the housing coated with the adhesive layer is φ₂, wherein φ₂ < φ₁.