This battery is no longer available, the best suitable alternative is https://www.partshopdirect.co.uk/dewalt-de9503-18v... Either that or you need to upgrade to a new drill kit that uses the XR Batteries.

Please Note: This is a DE9182 Battery which is a newer lighter weight version of the DE9180

DeWalt DE9182 18v Nano Battery Pack is the DeWalt exclusive nano-phosphate lithium ion cells offering long battery life & durability, 2000 recharges, the lightweight design provides the user with 18v power for the equivalent of 12v NiCd/NiMH pack weight, this battery has no memory effect and no self-discharge for maximum productivity & less downtime and is compatible with most older DeWalt 18v power tools