From an AP article:

"Battery technology has matured significantly during the past two decades as not only the world but also energy has become increasingly mobile. LIBs have grown to become the dominant battery technology across a wide range of applications. It is a disruptive technology that will significantly alter a variety of industry sectors, including consumer electronics, energy, oil & gas, transportation, and maritime. LIBs have the potential to be one of the best sources of power for Unmanned Underwater Vehicles (UUVs), torpedoes, and submarines, because their compact designs bring higher efficiency and strengthen reliability for underwater applications."

https://oklahoman.com/article/feed/10087576/lithium-ion-batteries-for-underwater-applications-2020-thematic-research-report-researchandmarketscom