A business analyst is a person who bridges the gap between IT and the Business. He is the person responsible for gathering the requirements from clients and documenting them in a neat way.
The business analyst is responsible for identifying what the business really needs without limiting the options of the team responsible for finding and developing a suitable solution to those needs.
As a business analyst will have to collaborate with the technical team, discuss possibilities and provide options to your customer. Managing your projects by creating timeline, tracking deliverability and continuous communication with your stake holder. Business analyst may also need to do budgeting for your project.
Business Analyst will also be required to understand the business process well enough and at the very least able to learn quickly as often you need to understand what your customer is trying to communicate. In addition, a good technical (not expert) background will also help you to come up with a better solution since just relying on technical team is just simply not enough.