"white vinegar" search

checked the top Google results but did not find any mention to either dilute with water or use full strength.
https://hallmark.custhelp.com/app/an...line-batteries.
https://www.bobvila.com/articles/how...ery-corrosion/
http://www.radioworld.com/columns-an...inegar-is-your friend/323304

John and Reinhard do you have any references for your recommendations?