You  have a 12 volt 1 amp power supply. The output power is listed as 12 volts DC  at 1000 ma  (or 1.0 amps).
You should get a power supply capable of supplying at  least 7 amps  but 10 amps or more would be better.  New power supplies with high amp outputs are not inexpensive. Some folks get computer (either PC or mainframe) power supplies and convert them to be used  for battery chargers.

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