## 1 Introduction  
With the advancement of the global energy transition and the implementation of low-carbon development strategies, electric vehicles have become a crucial component of modern transportation systems [1]. In particular, electric micro commercial vehicles have experienced rapid market growth due to their cost-effectiveness, environmental benefits, flexibility, and maneuverability. With the increasing number of electric vehicles, their safety has become a growing concern for both industry stakeholders and society. Automotive safety performance remains a key determinant of market competitiveness, and new vehicle models must undergo rigorous crash safety testing before market entry. According to statistics, in 2021, side impact accidents caused 21.9% of passenger car occupant deaths and 11.3% of light truck occupant deaths [2]. Side impact tests primarily comprise two categories: side moving deformable barrier (MDB) collisions [3, 4] and side rigid pole collisions. Researchers worldwide have extensively studied these collisions and identified a critical issue: when a vehicle's side lacks sufficient buffer space and energy-absorbing structures, the impact force transfersdirectly to the body components, significantly compromising occupant safety. Recent research has increasingly focused on side pole impacts, as these incidents often result in more severe body damage. This severity stems from the highly concentrated impact area, limited energy-absorbing space, and the likelihood of secondary collisions between vehicle components, presenting substantial risks to occupant safety [5]. Electric vehicles (EVs) introduce unique challenges in side structure design owing to their distinct power system architecture--such as floor-mounted battery packs and centralized electric drivetrains--which fundamentally differ from the engine-front and fuel-tank-rear layouts of conventional vehicles [6]. These differences necessitate innovative approaches to crash energy management and structural integration. Researchers have made significant contributions to addressing these challenges. For instance, [PERSON] et al. conducted a simulation study on side pole impact for a two-seat small electric passenger car based on the earlier E-NCAP evaluation standard [7]. Their research employed multi-objective and multidisciplinary optimization techniques to enhance door stiffness. This optimization significantly improved overall side pole impact performance. By incorporating floor-mounted collision beams and reinforcing door sill beams with aluminum alloy profiles, they achieved notable reductions in B-pillar intrusion. These findings provide valuable insights for improving the crashworthiness of electric vehicle side impact structures. With the rapid advancement of new energy vehicle (NEV) technologies, side pole impact safety has emerged as a critical research frontier in electric vehicle (EV) development [8; 9]. While early-stage studies primarily focused on isolated component analysis, contemporary methodologies continue to face two systemic limitations. First, body structure analyses predominantly rely on body-in-white (BIW)-only simulations, which fail to capture the critical interactions between the battery pack and load-bearing structures [10; 11]. Second, battery safety evaluations often assess enclosure integrity in isolation, neglecting its synergistic role within the vehicle's crash energy management system [12; 13; 14]. Although emerging efforts--such as integrated BIW-battery simulations for passenger EVs [15; 16; 17; 18]--have shown promise, they remain constrained by two significant gaps: (1) existing integrated models are primarily validated for passenger vehicles, despite fundamental design divergences in electric micro commercial vehicles (E-MCVs); and (2) current frameworks inadequately address the conflicting demands of battery protection and cargo-oriented structural rigidity in E-MCVs. The urgency of addressing these gaps is underscored by the unique crash dynamics of E-MCVs.