The battery pack you are holding is advertised as a 14.8v battery. How does the battery pack work if you are not supposed to use over a 12v power supply?
What he said was not 100% correct. No one of my friends use that battery because it's too expensive and actually it is same as jump starter, battery bank. Even electrodrill battery can be used perfectly.
@krishna dass I do that here in California and usually use my avet pro 4/02 or international sw 2speed and I do fine but my Japanese Daiwa tanacom 500 does the job a lot easier but get hated on if I win jackpot with it