Hi,
You may have to replace the complete battery box .
Here’s a link to the [https://elektrotanya.com/canon_powershot_s2_is_parts.pdf/download.html|parts manual] for the camera.
To download the file, click on the reCAPTCHA checkbox below the Document preview box and then on the Go to Download link
When the sentence below the Document preview box changes from ''This file is downloadable free of charge (5/day): ...processing...'' to ''This file is downloadable free of charge (5/day): Download (canon powershot s2 is parts),'' click on ''Download'' as this is the link.
Be patient as it takes a little while to find the file.
Out of interest I searched online for some of the parts pertaining to the battery area, by searching for “''Canon (insert appropriate part number)”'' with no success. You may have better luck.
If you also cannot find the replacement part required then this may be an [https://www.ebay.com/itm/Canon-PowerShot-S2-IS-parts-disassembly-/163084870534|option] to consider, if the price suits you.