I think the BIK is less than for ICE polluters?
Yes. Last week I had a coding notice from HMRC - they'd incorrectly re-classified my car into the max gas guzzling category and the benefit went up from £6k-ish to £53k!
They claimed it was my fault for filing the P11D incorrectly - allegedly the form has recently changed to have Electric as a distinct category when it was previously "other fuel". However, on checking the 2016-17 form it doesn't have that category, so on the face of it I was being penalised for not applying the 2017-18 rules to the 2016-17 form...