Citation :

Min-Woo kim, Hyeon-Gyo Jeong, Hyoung-Woo Lee, Dae-Goo Song, "Numerical Investigation of Thermo-Mechanical Reliability in Laser- Welded EV Battery Terminal Plate Assemblies," International Journal of Mechanical Engineering, vol. 13, no. 6, pp. 28-34, 2026. Crossref, https://doi.org/10.14445/23488360/IJME-V13I6P103

Abstract

The terminal components of high-power battery modules for electric vehicles are components that remain mechanically robust while carrying large currents and withstanding welding‑induced thermal loads. In this study, a terminal plate assembly made of a 1 mm‑thick brass plate with laser‑welded studs was selected as the analysis target, and its structural and thermal safety were examined using finite element simulations. Three configurations were considered: a flat base plate, a bent plate without studs, and a bent plate with studs assembled, to clarify the influence of bending geometry and stud attachment on mechanical response and thermal behavior. Under a bending load of approximately four tons, the maximum equivalent stress decreased from 56.17 MPa in the flat plate to 20.11 MPa in the bent plate and further to 18.86 MPa in the stud‑assembled model, indicating a clear reinforcement effect of the three‑dimensional load path. Transient thermal analysis of laser welding showed peak temperatures of about 1148.1–1153.2°C for simultaneous upper and lower welding, and the difference between the flat and bent geometries was minor because the heat source conditions and boundary constraints were identical. When the temperature field was coupled to the structural analysis, the resulting thermal deformation was limited to roughly 0.25 mm. The average thermal stress ranged between about 28.3 and 39.906 MPa, although localized stress concentration produced much higher maximum values. Considering these numerical results, the terminal plate assembly can be regarded as structurally and thermally stable under the assumed loading and process conditions. The analysis framework proposed in this study can serve as a basis for subsequent optimization of terminal geometry and laser welding parameters.

Keywords

Electric Vehicle Battery, Terminal plate assembly, Laser welding, Structural analysis, Thermal deformation analysis.

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