In this context, Silicon is a promising candidate for next-generation LIB anodic material in accordance with its high theoretical gravimetric capacity of ~4200 mAh/g and relatively low cost as the second most abundant element on earth . However, poor intrinsic electrical conductivity (~10 -3 S/cm) along with extreme volume expansion (~420%) during lithiation significantly hinders its rate capability and cycling stability, thereby commercially limiting the use of silicon-based anodes . The high electrical conductivity and mechanical stability exhibited by various carbon polymorphs has prompted extensive exploration of silicon-carbon composite anodes as a strategy for addressing the challenges associated with elemental silicon anodes, demonstrating notable enhancements in cyclic stability, capacity retention, and rate performance . Unfortunately, these composites frequently require costly and impractical syntheses, expensive binder materials, conductive additives and unsustainable carbon precursors . Additional, low overall silicon contents and not yet industrial-level stability in such anodes are notable issues. Due to these shortcomings, silicon-carbon composite anodes have yet to be widely implemented in commercial battery production. This being the case, this work proposes the first use of raw jellyfish biomass as a low-cost, sustainable, and eco-friendly carbon precursor for silicon-carbon composite anodes. Jellyfish biomass should be overwhelmingly abundant for the foreseeable future, with a study conducted across multiple marine ecosystems concluding that in a majority of the world jellyfish populations are rapidly increasing due to anthropogenic causes . Rising ocean temperatures caused by global climate change along with a plethora of human activities including overfishing and cultural eutrophication have induced large-scale ecosystem changes that were directly linked to increasing jellyfish reproduction rates and life cycles . This global jellyfish "invasion" is also having severe direct ecological impacts, with surging populations of jellyfish species causing massive disruptions in natural food webs and fluctuations in aquatic species populations globally , with several studies estimating that millions of tons of jellyfish are overtaking native fish populations in Namibia and the Barents Sea alone .