Do you have any Chemistry experience?
Have you refined metals using eletro/hydro/pyro metallurgy?
Have you read any books on the subject?
Anyone responsible as a precious metal refiner is going to ask you the same questions. The reason is because nobody wants to give detailed instructions to someone who has no experience nor any conception of the dangers involved.
If you are asking for step by step instructions on how to do something you never have done, then you truly and honestly have no concept of what is involved. You need to back up a bit and before learning how to recycle batteries, learn the basics and fundamentals before attempting anything more involved, like batteries.
Although being an electrical engineer may help you understand electrochemistry better than someone who is not, it's not going to give you any advantage when dealing with acids, or smelting for example. Nor is it going to be useful in taking apart the batteries so that you can begin to process them.
I have a background as an aircraft mechanic, making pharmaceutical drugs, WAN administrator and a business owner among other things. Some of those experiences have lent a hand to understanding the methods and processes in recovering and refining precious metals, but none of them could have possibly prepared me enough, to process watch batteries by following implicit instructions. This type of chemistry is far more dynamic than following recopies or directions. It takes being familiar with the different reactions, selectively dissolving and precipitating different metals, using different processes and being able to observe, and then change accordingly. It means becoming familiar with the most simple reactions all the way through to the more complex.
There is a learning curve, and if you are just now starting out, it's going to be awhile before you should even play with the idea of refining watch batteries.
Scott