Spent automotive batteries contain a wealth of precious materials that need to be recycled efficiently and sustainably. However, battery recycling currently requires elaborate and environmentally challenging chemical processes to extract some of the most sough-after raw materials such as copper, cobalt, nickel, manganese, lithium, and graphite. Direct recycling, an alternative approach, seeks instead to keep the active cathode and anode materials intact, rather than to deconstruct them to their raw elements during the recycling process. The so recovered active materials can then be reused in batteries directly after some relithiation - reducing unnecessary processing steps. Direct recycling offers significantly improved sustainability, lower greenhouse emissions and could lead to cost savings of up to 43%. However, direct recycling is still in its infancy and significant technological leaps are required to establish a UK-based direct recycling industry. A major challenge to enable a direct recycling industry lies in the efficient and accurate classification of the lithiation content in the spent active materials. Knowledge of this quantity will determine the amount of re-lithiation required and sets the value of the spent material. ReLIGHT will overcome this technological hurdle to accelerate the UKs transition to a direct recycling industry. Rooted in illumion's charge photometry technique, a revolutionary methodology to characterise the amount of charge stored (i.e. the degree of lithiation) in battery materials using light, ReLIGHT will demonstrate the feasibility for a low-cost and high-throughput classification methodology of the lithium content in spent automotive batteries. The project will partner with the University of Birmingham, a world-leader in recycling of lithium-ion batteries. By combining this set of expertise, ReLIGHT aims to bring direct recycling to the centre stage of battery recycling and pushing ahead with installing a circular and sustainable energy economy.