Global demand for critical minerals is accelerating as electrification, battery energy storage systems, and electric vehicles reshape energy and mobility systems. Despite this rapid growth, the global battery value chain remains highly geographically concentrated, with China dominating multiple stages of mineral processing, battery materials production, and cell manufacturing. This concentration exposes the global energy transition to supply chain vulnerabilities and geopolitical risks, particularly for emerging critical mineral economies across the Indo Pacific. The Indo Pacific, particularly South-east Asia and Australia, holds a uniquely complementary set of resource, industrial, and policy capabilities within the battery ecosystem. Australia is a leading producer of lithium and other critical minerals, underpinned by robust environmental, social, and governance (ESG) standards. South-east Asian economies, notably Indonesia, possess globally significant nickel resources and have rapidly expanded domestic processing and midstream battery material capacity. However, much of the region remains concentrated in upstream production, with limited capture of value in midstream and downstream segments. This paper presents an analysis of strategic collaboration opportunities to strengthen regional critical mineral and battery supply chains within the Indo Pacific, with Australia and Indonesia examined as a focal partnership. It explores pathways for joint development of processing and refining capabilities, regional research and innovation cooperation, and greater alignment of ESG, traceability, and certification frameworks required to access global markets. The analysis also considers how policy coordination and private sector partnerships can support regional integration across the battery value chain. The findings suggest that deeper regional collaboration could enable Indo Pacific economies to capture greater economic value, enhance supply chain resilience, and position the region as a competitive, sustainable alternative within the global battery ecosystem. These insights are relevant for governments, investors, and industry stakeholders seeking to accelerate secure and responsible critical mineral supply chains in support of the global energy transition.