Redd

I'm about to play musical chairs and move my stock 2014 Q5 battery to another car for another purpose. Which would give me the opportunity to replace it with the biggest battery that can be installed.

I know there are some factory options, and the car may want to be reprogrammed unless I lie to it (which I can do) but does anyone know...

What is the largest group size AGM battery that can fit in the same battery compartment?

What kind of games (VagCOM? dealer? Just lie?) does the car require during battery replacement?

tomaszp72

Just lie to it .......

Redd

Works for me.(G) AFAIK a charge control system should only give a damn about the battery voltage, and be able to deal with the rest based on that. If I have extra capacity, hell, that's just my private reserve fund, right?

tomaszp72

right...

DanMontgomery

Redd,

Very interesting....Haven't done any research, so not even sure it is even possible.

I was thinking about a dual battery set up. I done them on my trucks in the past. I have 2 small (for imports) YELLOW top Optima batteries in the Garage. I had them for my truck but sold it. The Audi battery is so huge, thinking I could put 2 of the small Import Optima in the same spot.

Long story, short....would like to know more about what you mean by "Just Lie to it"

V/r
Dan

Redd

Bosch and AC Delco both show AGM batteries for the car. Bosch only shows one for all Q5's (on Amazon anyway) while AC Delco shows two, one "wider" and the other "fatter", Group 48 and Group 49 if I read them right.

But dual batteries are actually a stock option in the EU. Spijun forwarded some information to me, apparently the Q5 is used as a medical or emergency response vehicle, and can be factory ordered with dual batteries and other niceties that we are not told about.

I had dual batteries on another car. Just wired up #2 to feed off a Yandina/West battery combiner and cabled it back with #2AWG cables--with the positive fused at both ends, just in case. The only problem is that the alternator on that car wasn't particularly bright, and AGMs can be very hungry, so they can overheat an alternator and shorten its life.

I expect the Audi stock setup does something to accommodate that but you'd probably need to contact Audi in Germany to enquire.

DanMontgomery

Redd,

Thanks will contact Spijun soon....and see if I can get more details.

Wonder if they used a different Alternator for that (medical or emergency) Q5?

Also, what else is installed on it?

Can they be used for "OUR" advantage?

V/r
Dan

Bob Petruska

The OEM size in the Q5 if more than enough...............

I have both a 2014 Q5 and a 2014 Honda CRV. The Honda CRV battery is soooo small in size but more than capable in my 10-20 degrees F, PA winters.

Redd

Heck, Bob, you've made an assumption again.

I've started marine diesels with a a 17Ah AGM battery, that's barely half the size of a big city phone book. I don't need more starting power.

In fact, a "big" jump boxlike the AAA uses commercially, only has a 12Ah or 17Ah battery inside it, and that starts cars and pickup trucks all day, every day.

But all batteries have a set limit of charge cycles in them, and the plain physics of it is that the more capacity the battery has, the less percentage of charge you take in each cycle. For AGMs in general, you might get 5000 cycles at 30% discharge, 2000 at 50% discharge, and only 500 at 80% discharge. (Don't get hung up on the numbers.) The thing is, the more capacity, the less juice you suck each time, proportionate to the capacity, and you can double the life of the battery just upsizing it a bit.

In my case there's something you didn't need to know, I *do* have a requirement to occasionally deep cycle the battery, so going to a larger capacity battery might double the life for my purposes.

The last one gave me eight years before it had to be retired.

This has got nothing to do with starting a car.

Bob Petruska

I agree with the above

Now why are you deep cycling an OEM vehicle battery, they are just not made to do that!!!

My 2002 Audi A4 OEM battery lasted 8 years with normal use.

I guess I'm not cheap, If I needed a battery every year so it be.................