Question Battery Replacement

I think this battery will work. Look at your existing battery for a part/model number. As it says which part numbers it replaces in its descriptions.
https://www.amazon.com/Battery-PA51...=PA5186U-1BRS&qid=1558707717&s=gateway&sr=8-4


This battery is listed for the S50-B. It says it replaces part numbers PA5184U-1BRS, PA5185U-1BRS, PA5186U-1BRS and PA5195U-1BRS. So, I looked up those part numbers on Amazon. However, Amazon does not list the S50-B. So you should look at your existing battery for a matching part number. I prefer the Amazon battery as it has a good review average. Plus I think the reviews are legitimate. I'm just listing the Newegg battery as my source.
https://www.newegg.com/p/16J-000N-14D24