ผลของพอลิแอสพาร์เทตในเจลอิเล็กโทรไลต์ต่อสมรรถนะของแบตเตอรี่ชนิดตะกั่ว-กรดแบบวาล์วควบคุม

• Main Author: ผกามาส ทันดอน
• Other Authors: นิสิต ตัณฑวิเชฐ
• Format: Theses and Dissertations
• Language: Thai
• Published: จุฬาลงกรณ์มหาวิทยาลัย 2011
• Subjects: แบตเตอรี่; ตะกั่ว; Electric batteries; Lead
• Online Access: https://digiverse.chula.ac.th/Info/item/dc:34613
• Institution: Chulalongkorn University

This thesis studied the effects of polyaspartate in gelled electrolyte on performance of valve-regulated lead-acid (VRLA) batteries. First, the conditions for preparing the gel electrolyte such as the amount of fumed silica, stirring rate and amount of polyaspartate were investigated. Then, several electrolyte formulations were selected to fill in VRLA batteries and the VRLA batteries were tested under different application conditions. The results showed that by increasing the fumed silica content or stirring rate, the gelling time were shorten and the gel strength were increase, while an addition of polyaspartate into gel electrolytes was found to increase the gelling time and reduce the gel strength. The cyclic voltammetry results indicated that the addition of fumed silica into electrolyte and the increasing of the stirring rate should have no effect on the main reactions in lead-acid battery operation but could reduce the hydrogen oxygen evolution reaction rate, and by adding more polyaspartate would also reduce the rate. The batteries performances were tested under 100% depth of discharge condition and the results showed that the gel batteries had higher discharge capacity than the non-gel batteries. The gel batteries prepared from 4% w/v fumed silica and 0.005% w/v polyaspartate at 2,000 stirring rate provided the highest discharge capacity which is the best condition in this study. Thus, the investigations of battery performances on different applications were compared among the non-gel battery and the gel batteries both with and without polyaspartate. The results indicated that the gel battery with polyaspartate yielded the best performance on every application studied. It had lower self-discharge rate, longer cycle life, higher discharge performance under partial-state-of-charge condition at both normal rate and high rate and higher discharge performance at different temperature operation. The properties of negative plates were investigated by XRD and SEM and found that the addition of polyaspartate had no sign of the presence the other additional compounds on the negative plates but reduced the size of lead sulfate crystals. The reduced lead sulfate crystal sizes leaded to the higher reaction area of electrodes which improved the battery overall performance.