A hybrid AC/DC lawn mower has a battery receptacle with a cavity for receiving a battery (100), a DC keyhole (S1) and a DC key, an AC power plug for connecting to an AC power grid, an AC keyhole (S2) and an AC key, and a motor (140). When the battery (100) is received within the cavity, then the battery (100) is operatively-connected to a DC circuit (110). When the DC key fit into the DC keyhole (S1), then it completes the DC circuit (110). The AC power plug is connected to an AC circuit (130), and when the AC key fits into the AC keyhole (S2), it completes the AC circuit (130). The motor (140) is operatively-connected to the AC circuit (130) and also the DC circuit (110).