This article addresses the line-balancing problem that arises when immersion cooling and AI cell monitoring are simultaneously integrated in-line into an ESS module-pack assembly line. Under the estimation scenario, the immersion-cooling station's process time is 135 s, exceeding the target module takt time of 92 s by 46.7%, making a bottleneck unavoidable with a single-station configuration. Parallelizing into 2 lines lowers the effective processing interval to 67.5 s, satisfying the takt-time condition, but this in turn raises the FIFO buffer size at the point where the two lines merge, and the module-serial tagging of AI monitoring data, as new interface risks. This estimation is a scenario based on assumed values…