How about keep the car and let him find his own way back to work.Once you have ended it it all responsibility for him ends so don't give him a lift to work is my advice,make it clear he is on his own and responsible for his own transport,that is a clean break.
Don't be afraid have people with you ready to dive in and help you leave once you've told him.Better still tell him by text and then block him,or arrange for talk about the kids and visitation to happen via a solicitor.Don't make it hard make it easy.I told my sister by text I wouldn't see or speak to her again,I wrote her a letter telling her she is considered a danger to my health and safety.When you put it in those terms you don't normalise it as a straightforward no fault split.I am not surprised you feel scared and nervous.Do it the easy way by text and let the bastard get his own transport to work.

My news is my sister I am cutting out completely as the last two years and I won't be fooled or manipulated again into talking to her like she fooled me over mum's cancer.With mum it is more complicated cos she has supported me lately and I am not going to cut her off completely just distance myself,be careful what I tell her and lessen her influence on me.I will still visit her but less often and phone again less often.I am confident it will all be ok.

Best of luck with cutting your abuser out of your life I myself would do it by text you don't owe him anything,but it is your decision,I wouldn't risk the possible abuse of doing it face to face.I am rooting for you Zedsdead,best wishes.