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Impact Factor (2025): 6.9
DOI Prefix: 10.47001/IRJIET
Impact Factor (2025): 6.9
DOI Prefix: 10.47001/IRJIET
Vol 10 No 5 (2026): Volume 10, Issue 5, May 2026 | Pages: 297-303
International Research Journal of Innovations in Engineering and Technology
OPEN ACCESS | Research Article | Published Date: 15-05-2026
Absorbent glass mat (AGM) separators in valve-regulated lead-acid (VRLA) batteries operate under sustained compression within assembled plate groups. Their electrolyte supply, gas transport, and mechanical resilience are strongly influenced by separator structure and compression state. However, conventional acid absorption tests are typically performed under unconfined or poorly controlled conditions and thus fail to reproduce the pressure environment experienced in service. This study presents the design and experimental validation of a novel pressurized acid absorption testing apparatus for quantifying AGM electrolyte uptake under simulated assembly conditions. The system integrates pneumatic pressure control (0–138 kPa) with real-time liquid-level monitoring via a calibrated observation window, enabling direct and accurate measurement of acid uptake under defined compression. Validation experiments using commercial AGM separators demonstrated good repeatability across the investigated pressure range and revealed a clear decrease in acid uptake with increasing pressure, consistent with the pressure-dependent changes in AGM pore structure. Compared with conventional static immersion testing, the proposed method provides a more realistic laboratory assessment of AGM absorption behavior under compressed conditions. The apparatus offers a practical platform for separator characterization, quality control, and future investigations into the relationship between uptake behavior and VRLA battery performance.
Absorbent Glass Mat (AGM) separator, pressurized acid absorption, acid uptake test, VRLA battery, electrolyte immobilization, testing device, liquid level measurement, pneumatic pressurization, battery separator characterization.
Lin Liang. (2026). Pressurized Acid Absorption Testing of AGM Separators in VRLA Batteries: Development and Validation. International Research Journal of Innovations in Engineering and Technology - IRJIET, 10(5), 297-303. Article DOI https://doi.org/10.47001/IRJIET/2026.105040
This work is licensed under Creative common Attribution Non Commercial 4.0 Internation Licence
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