# OEM Battery CCA?



## Uber-A3 (Feb 23, 2002)

Anybody know what it is for a 2.0t?


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## tiptronic (Apr 18, 1999)

Uber-A3 said:


> Anybody know what it is for a 2.0t?


Search!
OEM only had 480ca/280cca

Im using Duralast from Autozone with 600CCA

http://oooo-a3.blogspot.com/2008/11/group-48-battery.html


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## Uber-A3 (Feb 23, 2002)

tiptronic said:


> Search!
> OEM only had 480ca/280cca
> 
> Im using Duralast from Autozone with 600CCA
> ...


Thanks, I did search the forums but didn't goggle it. Duralast as well as all the other variations made by Johnson Control should have 690 CCA


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## tiptronic (Apr 18, 1999)

Uber-A3 said:


> Thanks, I did search the forums but didn't goggle it. Duralast as well as all the other variations made by Johnson Control should have 690 CCA


Sorry Uber- i was just trying to be funny, it didnt come out right 

U know more than i do re the A3 

e


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## VWAddict (Jun 12, 1999)

While there's a tendency to conclude that 'more is better', there's an argument against basing any selection purely on CCA.

Cranking amps (maximum current limitation) is -as I understand it- generally limited by the surface area of the plates in contact with the acid/electrolyte solution. More current capacity is achieved by more surface area.

So far so good... however...

Making more plate surface area is commonly achieved in conjunction with moving opposing plates closer together.

Again, so far so good...

But over time, dendrites grow in the liquid... -'whiskers' and 'branches' grow outwards from the surface of the plates.

http://leadacidbatterydesulfation.yuku.com/topic/1075/Battery-Additives-Misinformation-and-Spam

Over time these dendrites span the liquid gap between one plate and another, causing a cell to collapse, killing the battery. Super-thin or weak dendrites cause cell 'drain' -not a total collapse, but the sort of 'weak battery' crap which plagues the 'MOLL' battery used as OEM supply, for example.

SO... If you're only keeping the car for a year or two, by all means go for a ludicrously high CA/CCA rating. -If you're planning on keeping the car for a ling time, too high a CCA might mean a short battery life.

As in many things, there's a trade-off, and -albeit dramatically oversimplified- in this case, there's a cranking-amperes-versus-battery-life issue to consider.

Keith


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## Uber-A3 (Feb 23, 2002)

tiptronic said:


> Sorry Uber- i was just trying to be funny, it didnt come out right
> 
> U know more than i do re the A3
> 
> e


No worries, I didn't take it wrong.:beer:


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## A3_yuppie (Jun 5, 2006)

VWAddict said:


> While there's a tendency to conclude that 'more is better', there's an argument against basing any selection purely on CCA.
> 
> Cranking amps (maximum current limitation) is -as I understand it- generally limited by the surface area of the plates in contact with the acid/electrolyte solution. More current capacity is achieved by more surface area.
> 
> ...


Keith, you sound so knowledgeable about this. Do you have a recommended battery then? Preferably one that has the horizontal lip at the bottom so can be installed exactly the same.

I am on my second OEM battery at 75K miles, the one that came with my A3 died at 18K, and IIRC, the replacement one > the original one in both CA and CCA.


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## MisterJJ (Jul 28, 2005)

Walmart - Group 48. :thumbup:


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## VWAddict (Jun 12, 1999)

A3_yuppie said:


> Do you have a recommended battery then? Preferably one that has the horizontal lip at the bottom so can be installed exactly the same.


When mine failed (about 18k also) I went with the slightly-larger version -(forget which group it was; I'd have to lift the hood to find out!) but one with a comparable CCA number I think even though it was larger.

While so many batteries out there come from the same plant and use many of the same internals, I hoped that it might last a bit longer... So far I'm at right about 55k miles, and it's still fine, which means it's already lasted twice as long as the original...

I was thinking about building a box to desulfate the battery every so often... haven't had time to really get into it yet.

Keith


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## A3_yuppie (Jun 5, 2006)

VWAddict said:


> When mine failed (about 18k also) I went with the slightly-larger version -(forget which group it was; I'd have to lift the hood to find out!) but one with a comparable CCA number I think even though it was larger.


Please look when you get a chance and see if it's Group 48.

I am not sure that non-VW/Audi batteries have that lip I described for proper mounting.


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## crew219 (Oct 18, 2000)

OEM is a DIN H6.


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## Spitzbergen (Sep 10, 2010)

Auto Zone(and just about everybody else) sells their batteries with a warranty. Pick a battery you like with a warranty you can live with.


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