There are a few exceptions to the 50% borrow limit. NFTs representing an EGLD-unstaking position on JewelSwap (JWLEGLD) or on Hatom (sEGLD) have higher borrow limits. Their respective borrow limits are 90%. This means you can borrow 9 EGLD against an EGLD-unstaking NFT worth 10 EGLD. More exceptions to the 50% borrow limit may be added in the future.