Since the period of popularization of aluminium cans since the 1960s, aluminium can weight has been reduced over the years through material and process development – a typical 355ml aluminium can in 1965 weighed approximately 21 grams, whereas the same in 2023 is 12.5 grams (a reduction of 40.5%). According to the International Aluminum Association data, the tank thickness was compressed from 0.34mm in the 1970s to 0.10mm in the 2020s, and the compressive strength was increased to 620kPa (originally 350kPa) by the grain refining technology of 3104 aluminum alloy (grain size ≤15μm), and the transportation damage rate was reduced by 72%.
Production process innovation is a key driver, with Drawing and Ironing accelerating tank wall thinning from 0.005mm/year (1980-2000) to 0.015mm/year (2000-2020). Ball Corporation’s NexTec technology launched in 2018 replaces laser welding with traditional joints (weld width 0.2mm→0.08mm) and reduces aluminium can weight by an additional 8% while maintaining an internal pressure bearing capacity of ≥90psi. Aluminium cost per can was reduced by 0.6 cents. The 2022 European Aluminum Can Manufacturers Association report shows that plants using this technology increase their annual production capacity by 19% and reduce energy consumption by 14kW·h/ 1000 cans.
Environmental laws have accelerated the lightening process, with the EU EN 13432 standard requiring a package recovery rate of ≥75%, reducing the diameter of the lid from 63mm (2000) to 52mm (2023) and the weight of the lid from 2.3g to 1.8g. Coca-Cola’s 2021 example showed that the weight of the 500ml tank was reduced from 16.5 grams to 13.8 grams (a 16.4% weight reduction), which increased aluminum can manufacturing per ton from 56,800 to 67,200 and reduced carbon emissions by 18%. Daiwa’s nanocoating technology (thickness of 50nm) reduces the tank inner wall protective layer by 97%, and the shelf life of the beverage is extended to 18 months (earlier 12 months).
The economic benefits of lightness are enormous, and in 2023 the global aluminum can industry will conserve 1.37 million tons of aluminum material (9.2% of annual production) due to weight reduction, which is worth $2.86 billion. American Aluminium Association approximates the saving on can weight decrease of aluminium as $0.03 per 1,000 cans of logistics cost per gram. Pepsi, in its 2020 financial report, indicated that its “Lightweight 2025” project will improve the profitability margin of can products by 2.7 percentage points, but it requires $120 million to modify the stamping mould (tolerance control ±0.01mm).
Technical difficulties persist, with the deformation rate of the high-speed filling line (2000 cans/min) increasing from 0.5% to 3.2% when the tank wall thickness is <0.09mm. In 2024, Ardagh Group implemented an AI visual inspection system (sampling rate of 500 frames per second), which enhanced the accuracy of identification of defective thin-walled tanks to 99.97%, but the equipment renovation cost was as high as $4.2 million per production line. Norway Hydro’s aluminum recycling technology (impurity concentration <0.1%) reduced weight volatility of the recycled cans from ±2.3% to ±0.7% and advanced the worldwide market share of recycled cans in aluminum from 48% in 2010 to 73% in 2023.
Future direction is toward the most extreme weight reduction, and Japan Toyo Tank’s ultra-thin tank of 0.07mm in thickness (weight 9.8g) that has passed through the 1.5m drop test (breakage percentage <0.01%) should be followed by a new PET coating (adhesion ≥4.5N/cm²). The International Packaging Research Institute predicts that by 2030, the weight of traditional aluminum cans will be over 10 g, but the problem of rising carbon dioxide permeability caused by thin walls needs to be solved (current 0.05g/ can · year → expected 0.12g/ can · year).