Please Help! Daymak ebike brake or hub issue

[Slavegoddess]

I desperately need experienced advice. I am the 3rd owner of what I believe is a 2008 Daymak Vienna however I believe it is a China made unit as all the writing on the controller and the batteries is Asian. I took out a small loan to buy an ebike as I do not drive and needed something a little more versatile then transit. A coworker had this ebike and he rode it everyday to work and even rode it to meet me to purchase it. However, I purchased new batteries and hooked them up and proceeded to attempt to ride it up the large hill that I must travel to get to work. About half way up the hill it got very hard to pedal and I started to go backwards. So I applied the brakes to stop rolling and tried to turn it around to go back down. The back wheel was not turning freely and the throttle would start to move the bike and then stop. The wheel when you turn it or use the pedal, vibrates and makes a rubbing sound almost like the brake is engaged. I have had someone help me check all the parts and we did locate a frayed wire to the rear hub motor which we fixed but now am at a loss as to what is the problem. It is still not working and I am now out a lot of money with no more to take it to a repair place. Does anyone know what this could be? ?

 

[x.l.r.8]

Loss of torque is usually the inability to deliver amps. You sure you wired up the new batteries correct and more importantly did you know their voltage before you started.
After that i would look at the rear sprocket and check that's not coming undone also the front one to ensure it's not rubbing. Also make sure the rear brake is not binding. Is it the same when you don't pedal. What about on the side stand. Did anything get hot like the brake caliper or the motor