So it is all about the software:

"The partnership will give VW immediate access to Rivian's software allowing the German car maker to use it in its cars."

German car maker VW to invest up to $5bn in Tesla rival Rivian (bbc.com)

Which may or may not help them depending how much architecture specific code there is and how aligned their architectures are.

Embedded isn't an IT solution, there is always a little specific code around in the name of performance and efficiency. Generally, abstraction layers are used to aid portability, but some functions will depend on the underlying hardware. The worst case is if they are using different network management concepts, OSEK vs AutoSAR or even based around different networking technologies.

Hello Roger:

You may have hit the reason why my experience with battery life is shorter than other members. The batteries we have in the US are all "maintenance free" versions (where one does not need to add distilled water). We haven't had the other type for maybe 40+ years.

Sudden Battery death is just that the power is not enough to start the car (just clicks) . I use a battery charger for a few hours to get it started, so I can get to the store and get a new one put in (after saving the codes first).

Peter Brooks

Palm Bay  

I have never seen a Rivian EV on our US local roads - maybe that is why they have never made a quarterly profit. 

Peter Brooks

Palm Bay

No, ours are all maintenance free as well. I've not topped up a battery in a very long time.

I still have an unopened tube of Bat-Aid tablets, but I have not been able to open a battery to use them for many years.

https://granvilleoil.com/prodInfo?pID=3

Topping up with water and adding a Bat-Aid tablet, then slowly charging the battery used to work wonders.

for the cheapskates among us , a tea spoonful of Glaubers Salts -  sodium sulphate, would work as a pick up to lower the internal resistance a bit, though I see from your link that the tabs also have Epson salts - magnesium sulphate, as well.

Probably joining the spare needles for the Gramophone on the shelf of "have not sold any for years" .

Mike.

Are you old enough to remember the con game of making petoil (gasoline) out of tap water by adding just a small pill?

The UK con involved a car with two tanks - one empty where the water/pill mixture was put in and another with real gasoline to show that the car then worked.

Peter Brooks

Palm Bay 

It's my understanding that old used 78 rpm records can still be obtained in antique stores over here! 

Peter Brooks

Palm Bay