There is long-term usage data that is very useful as well and hopefully the previous owner or dealer has not reset that data. I would ask them to go through the BMS recalibration procedure (drain down to below 10% and then L2 charge it in ONE session to 100%. Drive it for a couple of miles and check the max capacity of the battery. Hopefully the temperatures will be in the 70s when you do that. You will get a pretty good estimate of the battery SOH in combination with the cell voltage deviation numbers which should be less than 10mv after full charge soaking time.

 

drain down to below 10% and then L2 charge it in ONE session to 100%.

Won't cell balancing influence the result if you charge to 100% ? I thought balancing happened at 99% (?) so if that's the case charging to, say, 95% would be better.

 

A bit late as you've probably bought it now. But just tell the dealer you need the SOH or no deal. Should work!
Or drive it from X% to Y% and note the miles covered, M. 100% range for your style of driving for that route will be 100 x M/(X-Y) . Need to factor in temperature but max range will at about 20C. The greater the distance the better the accuracy of result.

 

Great, thanks!!!

 

Thanks. Challenge here is that these rural VW dealers have very little experience selling pre owned EVs ( or they can smell that I'm also inexperienced with EVs & think they can bluff me

What's the latest SW update I should look for??

Thanks for all the advice

 

What's the latest SW update I should look for??

If it has 3.2 or above everything should be fine. If it has anything below 3.2 it is missing a service campaign or two 😀.

 

One way to test it is just to take it on a test drive and see how much it delivers. If you drive it from 100% close to 0% and used kWh is close to what is expected I doubt there can be anything fundamentally wrong with it. Now I let the experts to correct me 😀.

That works, but it may be a trick to find a seller who will let you take a few hours to charge from 80-100%, then 3 more hours driving it 240 miles. With car scanner you can get the same kwh capacity info in <1 minute, plus the deltaV to tell how balanced the cells are.

 

One way to test it is just to take it on a test drive and see how much it delivers. If you drive it from 100% close to 0% and used kWh is close to what is expected I doubt there can be anything fundamentally wrong with it. Now I let the experts correct me 😀.

 

See this vid for someone who got the shop test done, and shows the results:

https://www.vwidtalk.com/threads/battery-state-of-health-tracking-spreadsheet.8359/post-150091

 

Thanks SunWizard, definitely need to take this into my own hands & out of the cute Kerryman dealer's hands

Just to close this thread out. I did find a report snippet with real data on another forum. So I'm all set.

 

Do I need to do something re there image or can folks see it?

I can see it, but if you cannot don't worry, it shows nothing of any use.

Or any other advice for buying a second hand id.3.

Yes buy a $30 dongle and use car scanner to check it yourself. Its such a useful tool that I always want one with any car I get, and have had the same dongle for 8 years using it with multiple apps. With car scanner you check state of health and the deltaV = difference in volts between the highest and lowest cell in the pack. If you search on deltaV you will see many threads here discussing that.

 

There is nothing of any use in the picture (which I can see.) I don't know why your dealer cannot perform a health check. Its easy with car scanner app and many of us here are checking it ourselves, see:

Battery state of health tracking spreadsheet

Here is how to get your battery health SoH number. You need an OBD dongle and the car scanner app (android or iOS.) read the Maximum energy content of the traction battery (MEC), and the battery min. temp. Degradation is the amount your battery MEC has dropped from new 77kwh for 2021-22 or...

www.vwidtalk.com

 

Thanks folks. Do I need to do something re there image or can folks see it? As this appears to be a VW document and as the next page even indicates that "the total stored energy refers to the accumulated electrical energy that was stored during the service life" having a value of 0 is non sense. What I'd love is a sample print out as I feel I need to educate this dealer This doesn't call out any bad cells, any tips or tools for that? Or any other advice for buying a second hand id.3.

 

The picture link is broken. Now I am curious what there is in the printout. ASCII picture needed !

 

If I log-out I can see the attachment, but when I re-login I cannot. 🤷‍♂️ Site still having some issues.