Hi Tanya!
I really wouldn't advise trying that.
Power supplies and chargers are two different things altogether.
Batteries are designed to discharge at a specific rate and most battery powered equipment is designed to operate at the amperage supplied by the batteries.
Chargers designed for rechargeable batteries generally tend to be fairly high amperage to promote fast charging which is controlled by built in micro circuitry.
Trying to combine the two could possibly damage both beyond repair, and also invalidate any warranties. Plus theres the risk of injury or fire if it decides to go off with a bang.
Check to see if the manufacturer of the kit does a power supply that can be plugged into a wall socket. Sometimes they come as optional extras.
If not, it may be possible to buy a power supply and connect it yourself, but you will need to carefully check the required voltage and current usage of the kit before you do. Also, if the kit is new and you modify it yourself, your warranty goes out the window even if it fails for a totally different reason.
If you are not sure, I would just stick with the batteries. Its much safer!
Bobbie