This Tablet Charging Cart with RFID from Luxor is the best option for securing and charging up to 30 tablets at once. The RFID locking system is easy to use; just swipe the card in front of the sensor to unlock. The system requires four AA batteries (not included) to function and the lock will notify you with a flashing low-battery light when you have less than 25 open cycles left so you don't have to worry about inconveniently being locked out. It comes with two pre-programed RFID cards with the ability to program extra cards if you would need.
The cart includes rubber coated 1" dividers that keep your tablets organized and protected. It also comes with two 16-outlet vertical electrical outlets that utilize space and are powered through two small holes that are in the bottom of the cart. The design of this cart also allows for plenty of ventilation which will keep you devices cool and safe from overheating. The padded top of this cart is 19.875W x 19.25"D and makes a wonderful work and presentation surface. The inner top shelf is 20.5"W x 11"D and can adjust in 1" increments from 3.25" to 7.25" from the top clearance of the cart to suit any need. The bottom and middle shelves each hold up to 15 tablets and are 18.5"W x 11.75"D. The top clearance of the middle shelf ranges from 8" to 12" and the bottom shelf top clearance is 11.25". There are also four 4" casters included with this cart, two with locking brakes that will keep your cart precisely where you need it.