Barriers Designed for Traditional Vehicles Prove Ineffective Against Electronic Vehicles in Collisions
In the realm of automotive safety, a pressing issue has emerged as the focus shifts towards electric vehicles (EVs). The difficulty in building standardized guardrails for heavy EVs lies in the complex interplay between mechanical impact absorption, thermal and electrical safety, and battery location within vehicle architecture.
Recent events have highlighted this challenge, with a viral video featuring a 7,173-pound Rivian R1T obliterating a highway safety barrier, and the Tesla Model 3, during a test, almost completely undermining the main impact rail due to its floor-mounted battery pack. These incidents underscore the need for protective systems that can absorb extreme impact forces while maintaining thermal stability and electrical isolation.
Heavy EVs, such as the Rivian R1T, GMC Hummer EV, and Tesla Cybertruck, are not much heavier than some well-optioned heavy-duty pickups, like the F-350 Platinum, which weighs around 7,600 pounds. However, unlike gasoline cars, EVs have a lower center of mass, making it harder for barriers to absorb impact energy effectively. This necessitates guardrails and protective structures that not only manage immediate structural damage but also prevent cascading failures such as thermal runaway or electrical hazards, all while not increasing weight excessively or compromising vehicle range.
The issue is further complicated because the weight distribution among vehicles is not uniform, making it difficult to design a single barrier with universal applicability. Guardrails must integrate energy-absorbing materials, reinforced chassis designs, and specialized gas venting to handle mechanical and thermal stresses. Protection systems include millisecond electrical isolation and controlled de-energization to safely manage batteries during and after a crash. Thermal barriers and fire suppression systems need to be incorporated to mitigate fire risk.
Battery packs in heavy electric vehicles are typically stored in specific areas such as under the floor or along the chassis to optimize space and center of gravity. This location affects how impact forces transfer through the vehicle structure during a crash. Placing battery packs low and centrally can improve vehicle stability but exposes them to direct impact forces, requiring robust shielding. Battery packs mounted externally or underbody are vulnerable to direct collision impacts and road debris, affecting crash energy management strategies.
In sum, the complex interplay of these factors makes it hard to build standardized guardrails for heavy electric vehicles without customized solutions tailored to each vehicle’s design and safety requirements. As America's fleet gets older, presenting new challenges for those who ensure vehicle safety, and vehicles, in general, have been getting heavier over time, the need for innovative solutions in this area becomes increasingly urgent.
[1] Source: Midwest Roadside Safety Facility at the University of Nebraska-Lincoln [2] Source: Various industry reports and research papers on electric vehicle safety and guardrail design
Electric vehicles (EVs), such as the Rivian R1T, GMC Hummer EV, and Tesla Cybertruck, require advanced protective systems that can absorb extreme impact forces, maintain thermal stability, and ensure electrical isolation, given their lower center of mass compared to gasoline cars. The challenge lies in designing customized guardrails that can account for the complex interplay between mechanical properties, thermal and electrical safety, and battery location within each vehicle's architecture, due to the non-uniform weight distribution among vehicles and the specific areas where battery packs are stored.
