@Mutsy -I can answer that for you because I also had that question. Usually with aggravated assault there is a threat of some kind and there is a use of a weapon.
I think that aggravated battery goes further and it involves a situation when a person causes so much harm to another person that they may be disfigured or develop some type of disability as a result of the battery.
For example, assault could be throwing an object at a person. Aggravated assault would be mugging someone and beating them up for their wallet. Here the person does not want to kill the person just harm them enough so that they can commit the crime.
An aggravated battery is a brawl or a fight that breaks out and depending on the physical damage of the victim, a person might even be charged with attempted murder. Both aggravated assault and aggravated battery are felonies in my state with fines up to $10,000 and jail time of up to 15 years. I hope that clears this up for you. These terms can be confusing.