Amazon.com: RYOBI - 1 x Lithium + 36 V Battery Compatible with all 36 V Max Power Gardening Tools - 4.0 Ah - Individual Charge/Discharge Cell Management and Regulated Energy - BPL3640D2 : Tools & Home Improvement
Amazon.com : Ryobi 36V Max Power Battery Lawn Mower (1x 4.0Ah) Cutting 40 cm : Patio, Lawn & Garden
Battery For Ryobi 36V 40V 4.0Ah BPL3640D2 RLM36BL BPL3650D BPL3620D BPL3626D2 OZ | eBay
My New Electic Lawnmower (Ryobi 36V 4.0Ah brushless motor) - YouTube