Effect of Al foil surface modification on properties of lithium iron phosphate batteries.

According to the requirements of Al foil surface modification, the surface of Al foil is baked, corona and coated with carbon, and 6 Ah pouch type lithium iron batteries is made. The effects of surface modification methods on the performance of Al foil, electrode plate and battery are evaluated through the tests of Al foil surface roughness, electrode plate rolling adhesion, electrochemical impedance, storage, cycle, etc. The results show that the surface roughness of Al foil is increased by 41% after corona, and the adhesion of the electrode sheet is thus increased by 3.166 times as much as that of the base foil. After corona and carbon coating treatment, the impedance of the battery is reduced by one capacitance arc between the aluminum foil and the active substance. The alter-nating current resistance(ACR) of the battery is reduced to 5.59 mΩ, and the consistency of the internal resistance of the battery is improved. Corona and carbon coating can improve the high current discharge performance of the battery, reduce polarization, and improve the discharge platform, but carbon coating is more significant than corona. At the same time, the coated carbon significantly improves the high temperature cycle. [ABSTRACT FROM AUTHOR]