There are a lot of threads on the subject already. Most starting off contributing more than is seen here. You might even find some information on those threads.
There are currently multiple discussions ongoing about the crash issues affecting both PC-EU and PC-NA when in Cyrodiil or in Battlegrounds. We are aware of this issue and an incremental hotfix is coming soon to resolve the problem. This thread is now being closed, but you can continue discussion in the thread here.