Home Depot has Milwaukee M18 18-Volt Lithium-Ion High Output 12 Ah Battery w/ 2x 3 Ah Batteries (48-11-1812P3) on sale for $249. Shipping is free.

Key Details:

• Fuel gauge onboard displays remaining run-time
• REDLINK Intelligence: Provides optimized performance and overload protection using total system communication between tool, battery and charger
• Versatility: Powers more than 250+ M18 cordless solutions