Industrial batteries in the electric power system of ‘Electricité de France’

More than 5000 industrial batteries are operating in the different power plants, substations and distribution centres of ‘Electricité de France’ (EDF). 2 V lead/ acid and 1.2V alkaline systems are used for different stationary stand-by applications: power station control, communication, etc. In nuclear plants, these batteries are part of the ultimate safety system ensuring the safe control of the reactor. The operating conditions of the industrial batteries at EDF, the different related battery technologies and the testing methods used to assess their operating ability are described. For selection, batteries undergo electric, seismic and ageing tests. Ageing sequences involve successive floating phases at a high temperature. Results on absorptive glass mat valve-regulated lead/acid battery testing are given. On-line monitoring methods are studied in order to evaluate the remaining available autonomy of the battery according to its state of ageing. In addition to these stand-by applications, EDF is also investigating the potential of future energy and quality applications of stationary batteries such as load levelling or storage of energy produced from renewable sources.