Quantum batteries have emerged as a promising framework for storing and delivering energy using collective quantum effects. While most studies to date have focused on nanoscale spin models, important questions remain regarding scalability, open-system dynamics, and connec-tions to astrophysical energy processes. In this work, we introduce the concept of a Quantum Stellar Battery (QSB), which generalizes existing models by incorporating collective charging, Lindblad-type decoherence channels, and scaling laws for energy and power. Using exact diago-nalization and open-system simulations, we analyze stored energy, power output, and ergotropy for small to intermediate system sizes. The results reveal distinct performance signatures and scaling behaviors that can serve as measurable predictions in near-term quantum platforms such as superconducting qubits, trapped ions, and Rydberg arrays. These findings not only bridge the gap between idealized nanoscale batteries and realistic implementations, but also open pathways for exploring speculative extensions at astrophysical scales.