Making method for rechargeable 3V button type lithium battery

The invention discloses a making method for a rechargeable 3V button type lithium battery with lithium iron phosphate as the anode and aluminum as the cathode. The method includes: mixing lithium iron phosphate, graphite, carbon black and polytetrafluoroethylene evenly, conducting drying, and then pressing the mixture into a wafers as cathode of lithium iron phosphate; mixing aluminum powder accounting for 50%-60% of the mass of the lithium iron phosphate with nickel powder according to a mass ratio of 95:5 uniformly and pressing the mixture into a wafer to serve as the cathode; adding 0.1mm polypropylene diaphragm and conducting punching into a wafer; in an environment with relative humidity of less than or equal to 2%, assembling a button battery, adding 1MLiFP6 into an EC/DMC (50:50) electrolyte solution, and performing sealing at a pressure of 3MPa; conducting 0.1C charging on the battery to 3.5V, and then keeping a constant pressure of 3.5V to conduct charging for 12 totally, thus obtaining the 3V rechargeable button type battery. The method provided by the invention has the advantages of simplicity, low cost, high capacity, strong deep discharge capability, and long cycle life, thus being suitable for large-scale industrial production.