Home Depot has Ryobi 18-Volt ONE+ Cordless Lithium-Ion Battery 2pk and Impact Driver. Only $49.00. Shipping is free on orders over $45 or free ship-to-store. $64 at amazon.

• Batteries: Up to 3X more runtime
• Batteries: Integrated LED fuel gauge to monitor remaining runtime
• Batteries: Delivers fade-free power in extreme weather conditions
• Batteries: Robust construction to protect against impact
• Batteries: Lithium-ion chemical composition resists drainage when idle
• Batteries: Easily snaps into place and detaches with quick-release buttons
• Batteries: Recharge on any 18V ONE+ charger
• Charger: Compatible with all RYOBI 18V ONE+ Lithium-Ion Batteries
• Cordless 3-Speed 1/4 in. Hex Impact Driver: Powerful design produces up to 1800 in./lbs. of torque to handle most fastening applications