TABLE OF CONTENTS To overcome some of the problems with conventional lead-acid batteries new construction and processing techniques have been developed that have resulted in the advanced lead-acid battery. These techniques have improved the retention of electrode material during high current charge and discharge, decreased the weight of the inactive materials used, optimised the active materials and improved electrolyte mixing.
The result of these actions has been a significant improvement to many of the operating parameters. These include an increase in maximum energy density from 35 Wh/kg to 45 Wh/kg, and a substantial improvement in maximum power density from 150 W/kg to 250 W/kg, made possible by the improved retention of positive plate material during high-discharge operation.
The number of 80 per cent deep discharge cycles before replacement is necessary has been increased from 1000 to more than 1500. Battery cost, however, is likely to be about two to three times that of conventional lead-acid when available commercially.
These improvements have been obtained by a number of techniques, including computer analysis and modelling of current distribution. This has led to improved grid structures and designs which have reduced the battery weight and internal resistance, and achieved better retention of the active plate material. There has also been considerable progress in reducing the weight of the inactive materials used for the battery casing, connectors, terminals and separators, by the use of carbon fibre, plastic and plastic lead-alloy materials as well as lead-coated aluminium positive grids and aluminium terminals and connectors.
Developments...
