A Safe Battery Casing for a Hybrid Battery System Consisting of Lithium‐Ion High‐Power and High‐Energy Cells in Marine Applications

This paper presents abattery module design for a marine hybrid traction system that must satisfy both high‑power (HP) and high‑energy (HE) demands. The module accommodates either HP or HE lithium‑ion cells on a common platform, using only a limited number of parts despite differing cell dimensions. Thermal‑runaway (TR) containment is critical; therefore cell‑level TR tests were conducted for each type to provide the basis for designing the module venting system. The HE cell, a 155 Ah NMC prism, is the most severe: it releases about 16 mol of gas and ejects roughly 1.1 kg of particles. To survive the hot particle‑laden jet, the module hood is a bilayer of stainless steel plus an ablation composite. A highly insulating aerogel gap‑filler sheet prevents propagation to neighboring cells. The module with 28 HE cells passes the TR test. A second module equipped with 88 prismatic HP cells (23 Ah LTO chemistry) also passes the TR test. The design thus provides a versatile, safe platform for marine hybrid batteries.