The K-Gro PowerPro is a ridable lawnmower built for K-Mart by MTD and Murray. Released in 1997. Model numbers: 13AL452F120 (38", 12 HP) & 13AQ695H120 (46", 18 HP).
Lynn, battery should be on the right side of the engine. If you give us the model and serial number (located under the seat) we might find more information about this mower.