Extract from Vehicle Electrical Principles course notes…
This is due to reduced electrical demands (for example, from not needing a 12 volt battery to start the internal combustion engine – ICE).
So many ICE powered vehicles are now fitted as standard with stop-start and alternator management systems.
On these vehicles the 12 volt battery has to still be able to operate effectively at lower states of charge (i.e. deeper cycling), and also be compatible with on-board power management systems.
From the early 2000s, vehicle manufacturers have been looking to more advanced 12 volt battery technologies. Since then, Absorbent Glass Mat (AGM) and Enhanced Flooded Battery (EFB) batteries have come into general use.
These 12 volt battery types are now to be found as standard on many vehicles. A select few vehicle manufacturers are also even offering a 12 volt Lithium-ion battery as a starter battery. The following 12 volt battery types are to be found on modern vehicles:
Lithium-ion (some vehicles)
Garage personnel need to be familiar with these different battery types to ensure correct service and maintenance routines are followed.
Most importantly, today’s 12 volt vehicle batteries require different procedures to be carried out when testing, charging and replacing the battery.