Exponent Associate Battery Engineer interview questions

I had total 9 hours of interview time. Here is the total break down. 1st interview : Directly from hiring manager. It was about 1 hour long from technical to generic interview questions. 2nd interview : With an associate. It was about 1 hour long from technical to generic interview questions 3rd interview : With a principle engineer. From technical to hypothetical questions, 4th and Final interview: With 7 people (30 mins each). Total 6 hours which includes 45 minutes presentation and 30 minutes lunch break. Pros : The team was very friendly, knowledgeable and diverse background. Cons: There was no feedback from the company. It felt awful specially when you spend hours /days over two months to prepare yourself for all the interviews.