A stacking device, comprising: a negative delivery mechanism configured to deliver a negative electrode sheet (a); a separator delivery mechanism configured to deliver separators (b) to two sides of the negative electrode sheet (a) such that the separators (b) are attached to the negative electrode sheet (a); a first heating mechanism arranged downstream of the separator delivery mechanism and configured to heat the negative electrode sheet (a) and the separators (b); and a positive delivery mechanism arranged downstream of the first heating mechanism and configured to deliver positive electrode sheets (c) to the two sides of the negative electrode sheet (a) such that the positive electrode sheets (c) are attached to the separators (b); wherein the stacking device comprises a stacking mechanism, a stacking platform and a pressing mechanism, wherein the stacking mechanism is arranged downstream of the positive delivery mechanism and configured to arrange the negative electrode sheet (a), the separators (b), and the positive electrode sheets (c) on the stacking platform in a laminated manner to form a stacked type structure, the stacked type structure comprises a plurality of bent segments and a plurality of laminated segments arranged in a laminated manner, and each of the bent segments is used to connect two adjacent laminated segments; the stacking platform is configured to carry the stacked type structure; and the pressing mechanism is arranged at the stacking platform and configured to flatten the bent segments; wherein the separator delivery mechanism comprises a second heating mechanism configured to heat the two separators (b) before the two separators (b) are attached to the negative electrode sheet (a); characterized in that the second heating mechanism is configured to heat the side of the separator (b) that is used to attach to the negative electrode sheet (a). a negative delivery mechanism configured to deliver a negative electrode sheet (a); a separator delivery mechanism configured to deliver separators (b) to two sides of the negative electrode sheet (a) such that the separators (b) are attached to the negative electrode sheet (a); a first heating mechanism arranged downstream of the separator delivery mechanism and configured to heat the negative electrode sheet (a) and the separators (b); and a positive delivery mechanism arranged downstream of the first heating mechanism and configured to deliver positive electrode sheets (c) to the two sides of the negative electrode sheet (a) such that the positive electrode sheets (c) are attached to the separators (b); wherein the stacking device comprises a stacking mechanism, a stacking platform and a pressing mechanism, wherein the stacking mechanism is arranged downstream of the positive delivery mechanism and configured to arrange the negative electrode sheet (a), the separators (b), and the positive electrode sheets (c) on the stacking platform in a laminated manner to form a stacked type structure, the stacked type structure comprises a plurality of bent segments and a plurality of laminated segments arranged in a laminated manner, and each of the bent segments is used to connect two adjacent laminated segments; the stacking platform is configured to carry the stacked type structure; and the pressing mechanism is arranged at the stacking platform and configured to flatten the bent segments; wherein the separator delivery mechanism comprises a second heating mechanism configured to heat the two separators (b) before the two separators (b) are attached to the negative electrode sheet (a); characterized in that the second heating mechanism is configured to heat the side of the separator (b) that is used to attach to the negative electrode sheet (a).