Pros
Interesting science (sometimes). Decent instruments. Legacy of company will serve one's resume well. Cost of living in Columbus is not bad, so salary is adequate.
Cons
Battelle has a long legacy of being an honest, diligent science company. Then it got highjacked, and is now a company that will say and do whatever it takes to get a gov't contract. Company has not only put out fraudulent message, and sometimes data, (breaking their own code of ethics) but now goes to deliberate lengths to purge all criticism. This will result in a tragedy eventually. That's top level view. For details this company is terrified of IT, and handicaps itself in the way it handles IT, data, etc. Company hires way too many people based on diversity, and thus gets far too many people who can't do the work properly.