A good ID badge will always have:
Logo and branding of your business
Your ID badges should be instantly recognizable as part of your brand, even from a distance.
ID Photo
photo ID badges are much more secure than ones that do not have a photo. Make sure that the image is high resolution so it can be checked against the identity of the wearer easily.
Encoded data
as previously mentioned ID badges are more secure when they have either a barcode or encoded chip that contains specific information about the cardholder.  QR codes are a simple way to verify information using any device.
Additional security
To preserve the integrity of the card and prevent unauthorized copies, they can have additional security features such as holographic overlays