I doubt the cells could handle a charge rate higher than 4 or 5 amps, meaning as the best case it's going to take 3.5 to 4 hours to charge that battery from dead to full. And as mentioned, charging at high rates decreases cell life. Unless they are egregiously expensive, I would look into having two packs and just cycling them.
Now if you have a charger that's only putting out like 1 or 2 amps, yeah, you can absolutely charge it faster. The chemistry of the battery is going to determine what charger you need. Most of the DC-powered R/C chargers can handle all cell types, and several sub-$100 chargers will go up to 10A charge rates.
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