High Voltage Lead-acid Battery Modules

Abstract:
The use of lead-acid batteries as a back-up power source in telecommunication systems is well established. Valve-Regulated Lead-Acid (VRLA) batteries have been the technology of choice and these 12V products are connected in series to meet the higher voltage system requirements. Additional strings are used to increase capacity or allow redundancy. Atraverda has developed a component, based on a composite-laminate form of the Ebonex(R) material, that allows the production of higher-voltage lead-acid battery modules. Ebonex(R) is the registered trade name of a range of titanium suboxide ceramic materials, typically Ti4O7 and Ti5O9, which combine electrical conductivity with high corrosion and oxidation resistance. Details of the structure of the composite and battery construction techniques are discussed. In addition, performance data obtained by Atraverda from laboratory bipolar lead-acid batteries and cells is presented and compared with conventional designs. The characteristics of both conventional monopolar and bipolar batteries are reviewed. The findings indicate that the reliability is better due to fewer parts; better utilisation of active material leading to higher energy densities and cycle life is improved. Further advantages centre on the ease of directly constructing 24V, 36V or 48V units that may be connected in parallel to provide high capacity modules. The results indicate that the use of Ebonex(R) composite material as a bipolar substrate will provide lightweight and durable high-voltage lead-acid batteries suitable for a wide range of applications including stationary power and portable equipment.