If you have the "stop start" function, you have to fit either an EFB or an AGM, as they can cope with the heavy/deep discharge cycles & provide more power compared to "basic lead acid type".
EFB is cheaper, AGM is safer as you can turn the case upside down & even crack the case & no liquid will come out as the liquid is held in the Absorbent Glass Mat (AGM).....& they cost more because of this.
The MQB platform battery tray has 3 positions for the battery hold down bracket.....& VAG usually fit the size down from what the car ideally should have...
Ignore the Ah/rating on the Factory batteries as VAG use strange ratings on a standard battery case size designation.
I ripped out my factory mid sized Battery case size H5/027/Group 47, 59Ah/320A (DIN), EFB type battery & replaced it with the bigger case size H6/096/Group 48, 70Ah, 760A CCA (EN/SAE) AGM in January 2015yr....still going strong....I wrote a "how to guide" here...all info in first post:-
How to retro-fit a bigger capacity battery to a Mk7 Golf | GOLFMK7 - VW GTI MKVII Forum / VW Golf R Forum / VW Golf MKVII Forum
Mind you I have a Ctek charger that does normal & AGM types & also works as a 12V supply. There is usually gaps between the rubber seals on the bonnet & the top of the grill & the wires will go though that without being caught so you can close the car completely when charging.
When you swap the battery you need to code the BCM as per my thread above:-
VCDS coding required
From the Main screen:-
Select Control Module [Select]
[19-CAN Gateway]
Advanced Functions screen:-
[Adaptions-10]
New value choice screen:-
Change the following four channels, inputting the relevant data about the new battery.
IDE03256-MAS06105-Battery adaptation-Rated battery capacity
IDE03256-MAS06106-Battery adaptation-Battery technology
IDE03256-MAS06107-Battery adaptation-Battery manufacturer
IDE03256-MAS06108-Battery adaptation-Battery Serial Number
When you click on "Battery technology" (using VCDS 21.3.0) a drop down list appears with the following options (= actual meaning):-
Wet = Standard Lead Acid
Fleece = Standard A.G.M.
Wickel6V
Wickel12V
Ultracap
Gel = Standard Gel Lead Acid
Lithium ions = Standard LiFePO4
EFB = Standard E.F.B.
Binary - AGM = "Bipolar" A.G.M. type
EFB+ = E.F.B. "Plus" type
Not_assigned_10
Not_assigned_11
Not_assigned_12
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Unknown
According to various sources of information, including numerous car scans & threads on Ross-Tech, "Fleece" is for standard AGM batteries, "EFB" is for standard EFB batteries, & "Wet" is for standard lead acid batteries, as these settings are used at the factory. The setting of "Binary - AGM" is apparently for specialist "Bipolar AGM" batteries! Also the drop down list is from VCDS & not generated by your car's BCM, therefore, your car may not support all the options on the list, & the BCM will reject the value when you tell it to accept it!
Battery BEM codes are now redundant with the above separate channels. The most important channels are:- Rated battery capacity, Battery technology, & Battery Serial Number. For the Battery Serial Number, just change one digit of the old one. This channel tells the BCM that a new battery has been installed & to relearn the new battery & forget any “learnt values” for the old battery!