Toyota, a company renowned for its introduction of long-lasting cars like the Prius hybrid and hydrogen-powered Mirai, is now making strides in solid-state EV batteries. Despite its initial hesitation to fully embrace electric vehicles, Toyota's partnership with Idemitsu, a petroleum company, is propelling its solid-state battery research forward. By utilizing Idemitsu's raw materials, particularly sulfides from petroleum refining, Toyota is developing electrolytes for its innovative batteries. The decision to keep battery production in-house showcases Toyota's commitment to maintaining quality and reliability in its products. Furthermore, Toyota's collaboration with Idemitsu and sharing of patents with Panasonic underscore its dedication to advancing battery technology. The article also prompts a discussion on the potential impact of solid-state batteries in the EV industry, suggesting they could be a transformative breakthrough or just an incremental improvement. Despite Toyota's modest portrayal of its technological advancements, its history of pioneering technologies, from hybrids to solid-state batteries, highlights its ongoing role in shaping the automotive landscape.