ebay has them
https://www.ebay.com/itm/2-Pcs-Reention-battery-output-connector-for-Juiced-and-other-e-bikes/202928709529?hash=item2f3f7e5f99:g:V~0AAOSwYY1eZnmM
The contact points on this type of battery are notorious for failure. It's a design flaw. You can replace them. There are threads about "Juiced" batteries that identify the problem and replacement parts.