You did a basic web search, right? The Wikipedia pages for the Citroën Berlingo électrique (1998-2005) and Citroën Berlingo Electric (2010-) describe the vehicles; there's not a lot of battery information, but at the very least they explain that these two generations have completely different batteries... so which one is this? It looks like the E500 is the early one, with a NiCd battery from Saft that will be unreasonable to directly replace; that's why some online discussions are about upgrading to a more modern battery.