Today I went to clean the terminals on my battery as I was having trouble starting and I knew that dirt was causing it, so I undid positve/neg terminals and cleaned. Trouble is getting the nuts back on proved difficult as I didn't realise you had to take off the larger nut which connects the whole terminal plastic thing to the battery, I provide pic as I don;t know what its called! Its the large O ring shape thing to the right of the photo. Anyway, so this broke as I struggled to get the positive terminal nut back on with this larger nut connected! So its broke, off, the van still starts ok, but I am wondering what is the purpose of the large nut and will it cause harm by it being broke?
Thank you.

[url=flic.kr/p/2jUdAYp][img]live.staticflickr.com/65535/50474031151_e1b4cb9d31...g[/img][/url]

Edited by mikeandvan on 14/10/2020 at 00:10