Motorola Moto G (XT1033) - charging very slow after juice fell on it

Hi,
My phone got some juice spilled on it yesterday. It had a case on it,and that absorbed a lot of the juice (phone was in a bag) and turned on and off a few times after this occurred. Cleaned it as best as i could.
Phone works fine, but the problem i'm having is very slow charging when plugged in.
Is that something to do with the battery or is the phone itself damaged?
Trying to work out whether i should get another battery or just get a new phone?

Thanks.

 

Hi Androidmachine,

Thanks heaps for the response.
Will give that a go!
Just ordered a precision screwdriver set and will pull it apart and have a look at it.
Had let it dry for at least 4 hours prior to putting the cover back on it. Didn't charge it for about 10 hours after the incident (cleaned all the gunk off it then put it on charge as the battery was running low).
Phone still works ok, and has not re-started in the last 24 hours. Charging still stuck at 75%.
Has anyone else ever experienced something similar?
I'd really like to keep my current phone if it only means a battery change.
Does anyone reckon it could be something wrong with the circuitry (ie. something that requires a shop to fix - in which case it won't be worth that expense for me!).

Thanks again.

EDIT: Phone now saying "Charging: Six hours till fully charged" at 75%. Safe to assume it's the battery?

EDIT 2: Tried charging in safe mode and in airplane mode, still the same. Phone is able to maintain a charge but charges very slow. Phone still works fine (all functions intact) and has not restarted/switched off. Charging port also looks clean. Possible hypothesis : AV voltage insufficient for battery as it is damaged? Contact plates have been damaged??