Hi everybody, I cannot find any information what is the biggest AGM battery that can fit in my car.

 

At the moment i have an Exide EK700 70ah. I would like to upgrade it to a bigger one, due to quad dashcam setup. Is there any bigger battery that can fit in the car? Is there any secondary battery placement in the Superb III or not at all?

 

If the upgrade is not possible, i will use a secondary battery pack, placed under the passanger seat or in the boot.  There comes the next question: What is the biggest load the alternator can handle? And how fast these AGM batteries cahrging usually?

 

If somebody else have experience with Dashcams and external battery packs let me know:)

 

thank you

Be 8interested in an answer as well, but for it's for a nice loud (and hopefully better sounding) stereo system.

 

Thanks

Gel battery in the Middle of the spare wheel in the boot is possible, especially if you don’t have a spare or canton.

 

The trick would be to charge it only once the main battery was sufficiently charged and to not upset the the battery charge controller.

 

Otherwise I am sure I remember seeing an 096 with a larger capacity than 70Ah, however there is more to it than just that.

Edited 18 January, 20206 yr by cheezemonkhai

The problem you have if you start adding extra batteries is the charging arrangements.
 

The technology in the Superb III keeps the battery at around 80% to leave room to dump large amounts of current from the alternator during braking, this means the charging voltage drops which would stop charging any other batteries on board as well so you will need a battery to battery charger to manage it. (Expect to pay hundreds)
 

I suspect the alternator would be more than capable. 
 

are you planning on running all of these dash cams all the time?

Edited 18 January, 20206 yr by SuperbTWM

Slightly confused there.

 

Am I right in understanding that basically the alt is doing very little most of the time, but when braking its effectively acting like regenerative braking using the alt to slow the car down to charge the battery?

1 hour ago, Pessimal said:

Slightly confused there.

 

Am I right in understanding that basically the alt is doing very little most of the time, but when braking its effectively acting like regenerative braking using the alt to slow the car down to charge the battery?

That is correct. Some relevant info, up to micro hybrid 2 bit..

https://www.yuasa.co.uk/info/technical/micro-hybrid-hybrid-vehicles-explained/

3 hours ago, SuperbTWM said:

The problem you have if you start adding extra batteries is the charging arrangements.
 

The technology in the Superb III keeps the battery at around 80% to leave room to dump large amounts of current from the alternator during braking, this means the charging voltage drops which would stop charging any other batteries on board as well so you will need a battery to battery charger to manage it. (Expect to pay hundreds)
 

I suspect the alternator would be more than capable. 
 

are you planning on running all of these dash cams all the time?

The dashcams have to work minimum 10-12 hours in parking mode. (Constant when I am driving) there are some dashcam batteries like Cellink, but the prices are way to high. So either a second battery with an isolator, or a self build battery pack on the fuse box. I have Canton, but no spare tires in the car( foam, pump)

2 hours ago, Pessimal said:

Am I right in understanding that basically the alt is doing very little most of the time, but when braking its effectively acting like regenerative braking using the alt to slow the car down to charge the battery?

 

Yes, if you buy one of those cheapo battery voltage displays that plug into the 12v outlet you can see when the car charging the battery and when its just powering the ancillaries

 

10 minutes ago, QubiDK said:

The dashcams have to work minimum 10-12 hours in parking mode. (Constant when I am driving) there are some dashcam batteries like Cellink, but the prices are way to high. So either a second battery with an isolator, or a self build battery pack on the fuse box. I have Canton, but no spare tires in the car( foam, pump)

 

I would measure what current the cameras are drawing to get an idea of what you need but if you are adding extra batteries and want to charge them at a decent rate you will need something like this https://www.12voltplanet.co.uk/votronic-12v12v-30a-battery-to-battery-charger-vcc-1212-30.html

 

Only other option is maybe a low current battery charger that is just powered from the 12v supply but it depends how long your driving your car for each day  and how much power your dash cams are using.

On 18/01/2020 at 20:58, SuperbTWM said:

 

Yes, if you buy one of those cheapo battery voltage displays that plug into the 12v outlet you can see when the car charging the battery and when its just powering the ancillaries

 

 

I would measure what current the cameras are drawing to get an idea of what you need but if you are adding extra batteries and want to charge them at a decent rate you will need something like this https://www.12voltplanet.co.uk/votronic-12v12v-30a-battery-to-battery-charger-vcc-1212-30.html

 

Only other option is maybe a low current battery charger that is just powered from the 12v supply but it depends how long your driving your car for each day  and how much power your dash cams are using.

You are not the first one who mention a DC to DC charger...ppl recommending this one. https://www.renogy.com › 12v-...
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12V DC-DC On-Board Battery Charger | Renogy Solar

But the battery pack I wanted to build, should be charged max 15A. The Cellink neo 9 doing the same as rapid charge. The car fuse box would be enough? Or the cars alternator couldn't handle it?  Would be enough just to get a component like this?
https://a.aliexpress.com/_TzQuC. Or an additional buck booster...

And use the hardwire kit as a buck converter, with low voltage cut off?