The increasing requirement for sustainable and dependable energy storage has brought attention to the need for more thorough understanding of battery performance over the course of its useful life. In order to comprehend how aging impacts important performance metrics including voltage stability, charge-discharge efficiency, internal resistance, and capacity retention, this research provides a thorough investigation of lead- acid batteries at three different usage stages: fresh, moderately used, and aged. The study collects data in real time during controlled charge-discharge cycles using specially designed battery testing equipment that is connected to Internet-of-Things-enabled monitoring. The findings show distinct patterns in the behavior of degradation and emphasize the possibility of repurposing old batteries in secondary uses such as energy backup systems and electric cars. The results facilitate better decision-making regarding reuse, replacement, and recycling strategies by supporting more efficient battery lifecycle management. In battery-dependent systems, this effort advances the more general objectives of cost reduction, environmental sustainability, and energy efficiency.