Cell protective element with multilayer structure

Disclosed is a battery saver with a multiplayer structure, comprising a metal conducting strip and a current sensing unit which are connected to the anode and the cathode of the battery. Wherein the current sensing unit includes at least two parallel over-current protective devices which are separated by a hard insulating layer; the current sensing unit is clamped and arranged between the two conducting strips; the over-current protective device comprises in sequence an upper electrode layer, a conducting material layer with a positive temperature coefficient and a lower electrode layer. The over-current protective devices are connected in parallel by conducting through-holes or by conductors positioned at the sides; the section of the conductor can be shaped like a half round. A plurality of over-current protective devices are added in the utility model, therefore even if the over-current protective devices are burned due to improper use, the metal conducting strips connected to the anode and the cathode of the battery can still be prevented from short.