61 20... (Safety) information on AGM battery: Introduction

WARNING: This page is about a different car, the 2011 BMW 750xi, 2011 BMW 750Lxi, 2010 BMW 750xi, and 2010 BMW 750Lxi. However, it is still accessible from the selected car via links, so may be relevant.

In September 2002, the first so-called VRLA batteries, better known as AGM batteries came into use. (VRLA stands for Valve Regulated Lead Acid, i.e. lead acid battery with a pressure relief valve; AGM stands for Absorbent G lass M at, i.e. absorbent glass-fibre fleece)

The constantly increasing energy demand of modern vehicle electrical systems calls for ever more powerful battery solutions. A modern luxury-class vehicle has some 100 actuator motors that have to be fed with electrical current. Added to these are safety, environmental and comfort elements which are increasingly becoming standard features, such as e.g. Antilock Brake System (ABS), Dynamic Stability Control (DSC), steering servo (EPS), electronic chassis and suspension control, heating and air conditioning system and navigation system. Current consumption is considerable even when the vehicle is not in use.

The somewhat higher price compared with a battery of similar size is fully balanced by the following benefits:

greatly longer service life
improved starting reliability at low temperatures
reliable starting of engines with high starting current requirements, e.g. high-performance diesel engines
100 % freedom from maintenance
low risk in the event of an accident (reduced environmental risk)