Lithium ion: The next generation of long life batteries - Characteristics, life predictions, and integration into telecommunication systems

The basis and main features of the chosen Li Ion electrochemical system and technology are recapitulated, specifically focusing on the properties of interest in telecom applications. Aging reaction mechanism and expected calendar life are specially discussed. Accelerated aging experiments at high temperature under constant voltage floating conditions are described, with very promising results. From this preliminary evaluation, 15 years operating life without any maintenance can be anticipated in the application. Because of their voltage characteristics, and with their built-in electronic controls, Li ion batteries lend themselves to modular arrangements that are well suited to telecommunication applications. The paper will present such a design, for battery capacities ranging from 35 to hundreds of Ah at 48V, with drastically reduced weight and volume compared to existing systems. The need for cell charging control for lithium ion batteries, and the sa stem management of these batteries with regard to safety are defined and discussed. Finally, a sketch is offered for the integration of lithium ion batteries into today's telecommunications sg stems, alongside other battery types.