Connecting the negative jumper cable first to the mower and then to the good battery can create a spark at the battery that could ignite flammable battery gas and cause an explosion. Riding mowers use a 12-volt starting system. Make sure the good battery you use for jump-starting also is 12 volts. read more
You plug it into a wall socket once in a while to keep it charged, and when you need to jump-start a car or a mower, you tote it out and clamp the built-in cables to the dead battery. TOM: Another great option is a trickle charger. read more