According to Society of Automotive Engineers (SAE) standards, the range of inner diameter design for a common car cup holder is 70-75 millimeters, while that of standard 500ml can sizes is 66 millimeters (for regular cans) or 58 millimeters (for thinner cans), and the theoretical fit rate must be 100%. However, the actual tests reveal that due to the incompatibility of tank height (122mm for normal tanks and 140mm for thin tanks) with the cup holder depth (median value 90mm), there is an increased likelihood of tank shaking due to car use from 8% (correct depth) to 34% (ultra-deep tanks). For example, the depth of the cup holder of Tesla Model 3 is 95mm. Red Bull 500ml regular can (122mm height) is exposed to 27mm, increasing the risk of tipping by 22% when turning (NHTSA simulation data).
Industry case verification differences: In 2022, due to Anheuser-Busch InBev’s failure to reform the 500ml can size (diameter 66mm), its 78% fit rate for its energy drink in the cup holder (inner diameter 73mm) of the Ford F-150 (considered unstable when the gap between the can and the cup holder is ≥3.5mm). The following year, by reducing the tank diameter to 63 millimeters, the fit rate improved to 94%, and sales volume in the automobile channel rose by 19%. Japan’s Yamato Can developed short 500ml cans (58mm diameter) with a height of 110 millimeters for the Prius by Toyota. The outer exposed part of the can body was reduced to 15 millimeters, and rollover probability was reduced to 6% (JIS D 4601 vibration test).
Consumer research findings point out pain points: Nielsen’s 2023 report states that 43% of consumers dropped purchasing the 500ml can size because it was not compatible with the cup holder, among which the 18-35 age group was most sensitive (51%). To solve this problem, the Magic Claw Energy Drink utilizes a stretchable silicone sleeve with a thickness of 2mm to wrap the bottom of the can, widening the effective diameter from 66mm to 70mm. In filling up the gap in the cup holder, the anti-slip coefficient (μ) is raised from 0.3 to 0.6. The cost increment was $0.08 per can, but the rate of return dropped by 67%.
Manufacturer’s technical response: To be compatible with 500ml can dimensions, some automakers have adjusted the cup holder design. The 2024 Honda CR-V has expanded the inner diameter of the cup holder to 77 mm and increased the depth to 100 mm, raising the fit rate from 82% to 98%. However, it has sacrificed the stability of small cups (such as the 68mm diameter of Starbucks medium cups), and the probability of shaking has risen from 5% to 18%. In terms of material innovation, the BMW iX adopts shape memory alloy cup holders, which dynamically adjust the inner diameter (±4mm) through temperature sensing (20-40℃), keeping the 500ml can compatibility rate stable at 96% and increasing the cost of a single system by 230 US dollars.
The impact on sustainability cannot be discounted: The slender can (with a 58mm diameter) is better designed for use in cup holders, less likely to cause beverage splashing by shocks (with a 41% reduction in likelihood), and has the ability to decrease in-car cleaning expenditure every year by $12 per car (projected with a typical daily duration of driving as 2 hours). But the decrease in the thickness of the aluminium material (0.110mm→0.097mm) reduced the compressive strength of the tank from 240 Newtons to 210 Newtons, and the transportation stacking layers had to be reduced from 12 to 10 layers, resulting in a 17% loss in logistics efficiency (Amazon warehouse data). The industry has to balance flexibility and supply chain costs.