Would it work? Short answer is yes. Would I do it? No
The reason I say this is I have personally had a battery short on me, being the idiot I was also didn't run a fuse. Thus ruining a $90 battery, $80 hi-po motor, and $45 wiring harness. All because I could not tear the battery out fast enough. If you hardwire a battery in there, you are possibly looking at losing an entire gun that you have probably spent over $500 on.
Also, don't tell me you will just grab hold of this battery and rip it out, because you wouldn't be the first. You will permanently scar your hand from 2nd to 3rd degree burns. (especially if you do this with a Li-Po)
How do do I know this you might ask? Back in the day, I thought I was cool and hardwired 2 offroad lights on my rig, one day the switch had enough and started a smoke show(small fire) inside my truck. in my brilliant wisdom opened the hood and ripped the power wire off thus burning my hand. While the amperages are different here, the end result will be the same.
When it comes to power, play it smart, wire in a fail safe, such as a fusible link(no not a buss fuse). Find a link(wire) that will burn in half around 5-10amps.
just my