Today's Lithium (LI)-based battery has ushered in an era of cost-effective, gigawatt-hour-scale storage resources. However, the future of Li as the dominant or even preferred technology is uncertain. History is replete with examples of pioneering technologies being displaced by subsequent innovations, including lighting, computation, and power generation. Given the fundamental properties of candidate technologies and target markets, this article identifies a diverse technology portfolio as the most likely future for the storage industry.