Firstly, get an updated application catalogue from your supplier. All current application catalogues from Original Equipment suppliers are now listing information on Start Stop Fitments.
These listings can sometimes be confusing with multiple options listed for the same vehicle. Unfortunately this seems to be the way that the automotive aftermarket is changing. Where the battery size becomes dependent on the level of options and extras added to the vehicle at the time of manufacturing. It is always good practice to get as much information off the current battery in order to quote for the correct replacement unit. This of course becomes a little useless if someone has already put the wrong type of battery in, so the catalogues then become indispensible.
You can also ask the customer, if the vehicle has the Start Stop function. If it does, it will definately need a start stop battery. But be wary, many high end luxury vehicles now have start stop AGM batteries fitted even though they do not have the start stop function. The reason for this is the level of electrical equipment and drain that these vehicles are subject to.
Identifying a Start-Stop Battery (AGM or EFB) from sight :
These batteries unfortunately look the same as normal flooded batteries to the average consumer, rectangle box and round terminals. However, provided that the battery is the OE supplied unit or the correct aftermarket unit there should always be ways to help identify it.
As above, Mercedes tends to have the letters VRLA on the battery, this means “Valve Regulated Lead Acid” and it is an AGM battery
As above, BMW just has “Sealed Do Not Open”, but if it is BMW Original Equipment, black cased batteries are AGM, White cased batteries are normal flooded
Aftermarket units tend to clearly state AGM or EFB whilst also showing the Start-Stop Symbol.
Above are Banner & Varta AGM Batteries.
Above are Banner & Varta EFB Batteries
Other Battery Manufacturers who supply these products to the aftermarket also clearly state EFB and AGM on the batteries.
Denka 