So, if someone in an EU country builds an EV with a Chinese battery and sells it in another EU country: no harm, no foul.
If that EU EV is sold in a 3rd country that has an agreed FTA (you know who), the 3rd country has to slap a 10% tariff on it.
And vice versa.
And, if the EU EV has an EU battery, then the aforementioned 3rd country can't slap a 10% tariff on it.
And if the 3rd country with an FTA can't muster its own batteries then they still get lumbered with the 10% tariff when they try to flog the 3rd country EV in the EU.
So the people of the 3rd country will end up paying more for their EV than Johnny Foreigner and selling less of their home made EVs because of the EU FTA.
I ask myself, could this possibly be something to do with Brexit?