Battery is an intentional tort. It consists of making physical contact with another natural person through an intentional act either directly with your own body, or through an extension such as a weapon, including a firearm or a vehicle. It is enough that the tortfeasor intended to do something that was likely to cause contact - it is not necessary that the tortfeasor actually intended to make contact with a particular person.
Although battery is a tort, it is only actionable if the battery causes damages, although the damages may be caused in any manner. It is merely necessary that the battery was the proximate cause of the damages.
If there was no intention to make contact, no action lies in battery although an action may lie in negligence. For example, if someone deliberately hits you with their car, that is battery. If another person merely gets into an automotive accident with you, that is not battery, although it may be negligence. However, if a person is trying to hit someone else with their car and instead hits you, that is battery as their was an intention to perform an act that was likely to cause contact.
The de minimus of battery is very low. Merely putting your hand on someone constitutes battery.