Can my ex-business partner sue me for closing the company bank account that was in my name?

If you used the account as a business account, the assets in the account belong to the business (whether it is a partnership, corporation, or LLC). You say that it is in "your name," but it isn't clear to what extent the ex-partner had access to it. I don't take your ex-partner's claims of suing you to be especially worrying. Assuming you are a partnership, unless there is a written partnership agreement to the contrary, you have the right to withdraw from the partnership for any reason. Once the business relationship ends, there has to be an accounting to pay vendors, finish business for clients, and lastly, distribute any remaining assets to the owners. If you worried about your physical safety, don't wait -- you need to consult with a lawyer about your specific facts and concerns. Contact a good business litigation lawyer in your area as soon as you can.