Negative plates for lead–acid batteries containing lignin expander UP-414 with various phenolic group contents have been investigated. The members of the family of lignins UP-414 are produced by Borregaard LignoTech, Norway and differ mainly by the amount of phenolic groups and less so by the carboxylic groups in their structure, the content of all other functional groups (methoxyl, ketonic, etc.) being the same for all UP-414 products. | ELSEVIER Journal of Power Sources 113 2003 345-354 Influence of phenolic group content in lignin expanders on the performance of negative lead-acid battery plates M. Matrakovaa T. Rogacheva D. Pavlova . Myrvoldb aCentral Laboratory of Electrochemical Power Sources Bulgarian Academy of Sciences Sofia 1113 Bulgaria Borregaard LignoTech N-1701 Sarpsborg Norway Abstract Negative plates for lead-acid batteries containing lignin expander UP-414 with various phenolic group contents have been investigated. The members of the family of lignins UP-414 are produced by Borregaard LignoTech Norway and differ mainly by the amount of phenolic groups and less so by the carboxylic groups in their structure the content of all other functional groups methoxyl ketonic etc. being the same for all UP-414 products. The influence of phenolic group content in the expander on the performance of SLI batteries has been studied. It has been established that the batteries with PbSb grids exhibit a decline in C20 capacity CCA performance and cycle life when the content of phenolic groups in the expander increases. The capacity cycle life and self-discharge of batteries with PbSnCa grids do not depend on the content of phenolic groups in the lignin. It has been proved experimentally that lignin reacts with the ions of the grid alloying additives forming metal-lignin compounds which exert an influence on the performance of the negative plates. 2002 Elsevier Science . All rights reserved. Keywords Lead-acid battery Expanders Lignins Phenolic groups in lignin Metal-lignin compounds 1. Introduction Organic expanders based on lignins exert an influence on the processes of charge and discharge of negative lead-acid battery plates. Being surface active substances they also affect the hydrogen overvoltage on the negative electrode. This influence of the expander is mainly due to the functional groups in its structure methoxy phenolic carboxyl ketonic carbinol structural groups etc. which affect the
