Battery is an act by which a person intentionally or recklessly applies force to the complainant. This does not however, mean that the victim was 'beaten up' or even kicked or hit, it could be that they were pushed, grabbed or spat at.
The physical contact between attacker and victim is battery, whereas assault refers to the threat of violence.
If you feel you have been a victim of this you need to report it to your local policing team via the non-emergency 101 number. For more information please see the websites in related information.