Thermal box around battery - thoughts.......

[LeylandVCDS]

As per title, a question about the fabric thermal jacket around the battery.

When I bought my Leon 18 months ago, the jacket was missing completely. I rbought a cheap copy one from ALiExpress for £12, put it on, and thought nothing more of it.

However, after two battery replacements under warranty since, and still having low battery (seen from the stop start not working) on cold mornings, I'm wondering if it could be anything to do with the thin, basically cardboard only, AliExpress thing that's on there. The OEM version is obviously much thicker (when compared to the one on my mate's Skoda Superb) and would therefore be a far better thermal insulator, but do these thermal jackets actually do anything useful, or are they mainly there for cosmetic purposes?

Car has been checked numerous times for drain, and that's proved there is only a minimal discharge. Current battery is also reading excellent when tested, but takes a few miles from a cold start until the start/stop becomes available from high consumption by the vehicle

So my question is this - is it worth me actually investing in an OEM one to replace the thin cardboard effort on there now?

Happy New Year to you all!

Thanks
Mike

 

[cairus]

I bought an AliExpress case for the small Leon 5F. I don't notice any difference to my OEM. The OEM battery lasts on average 4-6 years, the battery that I buy from the accessories, only 3 manufacturers come into question for me, Varta Banner and Exide. All 3 also produce the batteries for VW. These also last 4-6 years.

 

[tracktoy]

Is it only the stop start issue you are seeing, in principle the stop start process (as i understand it) does not work if the engine is cold, if you have heated rear window or even if the heating is on full until the engine is up to speed.

In the past I have run without battery cover at all and had no issues but then I coded our Stop Start, as @cairus said I would expect battery to last between 4 - 6 years and personally I am a great believer in coding in the new battery (to aid longevity). However I would expect it makes a difference according to climate and how much you use your car.

 

[cairus]

The problem is not start-stop, but the braking/energy recovery. Therefore, the energy management keeps the SoC at 80%.

 

[ViperSlider]

What brand is your battery?

My OEM battery cover is thin as hell compared to the older ones so I can't imagine the OEM one would be much thicker than yours.

"Current battery is also reading excellent when tested, but takes a few miles from a cold start until the start/stop becomes available from high consumption by the vehicle" This is totally normal. S/S is never available straight off a cold start due to the numerous factors that it monitors.

Do you have any aftermarket items installed such as a dash cam or tracker?

 

[LeylandVCDS]

Thanks for your replies, much appreciated

The battery is a Bosch 70AH 760CCA Bosch EFB as in this which has been fully coded in correctly, and not showing any errors.

On the infotainment screen which shows stop start status, one of the options is "operating temperature not maintained". After a start on a very cold morning, that particular entry goes off within a couple of minutes. Defrost/blowers/heated screen are NOT on. This leaves only one other message which is "Vehicle power consumption high", and it sometimes takes up to half an hour of running for that to go off and stop start to work. After an overnight boost with a battery charger which is compatible for EFB batteries, the stop start works as soon as the operating temperature message goes off (less than a minute of running), and the high consumption message never appears. So the issue is definately something to do with lowering battery voltage.

No tracker (that was completely removed months ago) and front & rear dash cams are both on an ignition sourced feed, shutting down completely as soon as the ignition if switched off.

Stop start start limit voltage in address 19 Can gateway is set at 7.6 Volts

No VCDS errors anywhere in the car suggest an issue with the charging, voltage whilst running is 14.1 volts, so the alternator is working fine too. The only single recurring fault that comes up is the reverse camera not calibrated, which hasn't been sorted as the camera works perfectly

Just been out to the car today at 4.30pm after covering over 100 miles yesterday, and the high vehicle consumption message was there straight away. Car parked outside last night, temperature no lower than 8 degrees. There's no way battery voltage should be low after that.

@cairus - I'm not sure the car has braking/energy recovery? It's a facelift 2019 2.0TDI, engine code DFGA, with DSG

@ViperSlider - the AliExpress cover that's on is literally like a cardboard box with no padding. The OEM one on my mate's Superb is like a thick insulated squishy material like pipe lagging, so still wondering if a thicker one would be beneficial?

 

[cairus]

Of course your vehicle has the system. Measure the voltage when starting in the morning. Then use VCDs or something similar to measure the voltage when idling. If this is 12.xx volts, switch on the seat heating on both sides at the front and the rear window heating. The alternator is then told via LIN to charge more. Then the voltage must go up to 14.6V.

 

[LeylandVCDS]

Of course your vehicle has the system. Measure the voltage when starting in the morning. Then use VCDs or something similar to measure the voltage when idling. If this is 12.xx volts, switch on the seat heating on both sides at the front and the rear window heating. The alternator is then told via LIN to charge more. Then the voltage must go up to 14.6V.

You learn something every day! Never knew that, and now on my 4th Leon, and had 3 Octavias too!

 

[cairus]

the system was only really released to the masses with mqb

 

[LeylandVCDS]

My last Leon and last 2 Octys were MQB

 

[cairus]

What I meant was that in the PQ series it was not installed as widely in the models as with MQB in every vehicle.

Sorry , Bad Translation

 

[LeylandVCDS]

What I meant was that in the PQ series it was not installed as widely in the models as with MQB in every vehicle.

Sorry , Bad Translation

Hah, what I meant to say is that this is the 4th MQB platform I have had, and only just now learned any of them had this system fitted !

 

[cairus]

But you can circumvent the system up to a certain point permanently.

 

[LeylandVCDS]

But you can circumvent the system up to a certain point permanently.

Tell me more! Thanks

 

[cairus]

Not now...

Time for sleeping...

 

[ViperSlider]

Bosch is a decent brand so no concerns over battery quality.

Check your battery voltage before you start the car in the morning. I can see you've done multiple drop tests so now we should be doing alternator function tests as above to see if the consumers are triggering a charge increase.

 

[SuperV8]

Why did you pick an EFB battery - and not an AGM battery?
My genuine battery for my 2015 184 tdi was AGM.

 

[ViperSlider]

Why did you pick an EFB battery - and not an AGM battery?
My genuine battery for my 2015 184 tdi was AGM.

Largely EFB are fitted to petrol and AGM to diesel.

Can upgrade to an AGM but would need to record it on the vehicle correctly in the battery monitoring system

 

[SuperV8]

Bosch is a decent brand so no concerns over battery quality.

Bosch are just re-labeled Varta batteries - but with a 5 vs 4 year warranty.

 

[SuperV8]

Largely EFB are fitted to petrol and AGM to diesel.

Can upgrade to an AGM but would need to record it on the vehicle correctly in the battery monitoring system

Yes, that is my point - the OP has a 2.0 TDI - but has fitted an EFB.