The invention relates to an optimized novel lithium battery cover plate assembly. The assembly comprises a light aluminum sheet, wherein an explosion-proof valve is arranged in the center of the lightaluminum sheet, lower injection molding parts are connected with lower sides of two ends of a smooth aluminum sheet, a positive pole is arranged on the right side of the lower injection molding on the left lower side of the light aluminum sheet, a liquid injection hole is formed on a right side of an explosion-proof valve, a negative pole is arranged on a left side of the lower injection mold located on a lower side of the right portion of the smooth aluminum sheet, positive upper injection molding PPS is arranged on the outer side of the upper portion of the positive pole, negative upper injection molding is arranged on the upper side of the exterior of the negative pole, and sealing rings are arranged between the positive pole and the negative pole and the bare aluminum sheet. Under thecondition that the total height of the battery is determined, the battery capacity can be effectively improved, and the cost can be reduced by adopting the pole subjected to knurling treatment. The assembly has advantages of simple structure, safety, reliability, high space utilization rate, low cost and improved battery capacity.