Eliminate the battery and just use a 10 amp charger.
Nope, very bad idea. Most chargers will either put out too much voltage (they often have a high voltage start on charging and taper down as the battery charges), have excessive ripple current which can affect the motor's life, and often have very poor current/voltage regulation abilities.
Finally, a 10 amp or greater charger will often cost more than the 10 amp power supplies available from eBay, Mouser, DigiKey, etc.