The embodiment of the invention provides a soft
package battery and a preparation method thereof. The soft
package battery provided by the invention comprises a
battery cell and an aluminum-
plastic film coating the
battery cell, wherein the
battery cell is positioned between the two
layers of aluminum-plastic films; the edges of the aluminum-
plastic film are packaged together, so that the PP layerin the middle is melted to define a packaging part; the aluminum layer on the upper layer of the end, far away from the battery
cell, of the packaging part is bent downwards to partially coat the molten PP layer, and the aluminum layer on the lower layer of the end, far away from the battery
cell, of the packaging part is bent upwards to partially coat the molten PP layer. The invention also provides a preparation method of the soft
package battery. The preparation method comprises the following steps of providing the battery
cell and the aluminum-
plastic film, performing packaging, and
cutting edges. In the edge
cutting process, opposite shearing force is used for
cutting the packaging part, so that the two aluminum
layers at the end, away from the battery cell, of the packaging part arebent inwards to at least partially coat the PP layer of the packaging part. According to the soft package battery provided by the invention, the waterproof performance is improved on the premise of not increasing the production cost.