I also agree with the other poster as it may be his house too, so you need to consult your lawyer about it, be careful because he could turn around and say you have locked him out of his own house, get an alarm.
Also this collabrative divorce, was this his idea? because the "let's work all details out in divorce in a nice manner" is a sweet thought , however, if he physically abused you, um nope, why even agree to this? "couple" therapy needs to just be you, do not give him any more opportunities to see you let alone try to intimidate you. His lawyer can talk to your lawyer, so there is no contact needed between you. Not sure if you have kids, but if you are concerned about safety, then you need to have a visitation exchange in a very public place.
As women, we are supposed to "help" and caregivers, but that is a great big line of BS, as more often times then not we will sacrifice ourselves to care for someone who doesnt deserve it. You have done the first step by filing for divorce, however, a lot of times, since we are nurturers- the abusive spouse may promise to get help, etc and the cycle starts all over again. So you do need to toughen up and take care of you-kids if you have them.