Depends on the battery.
Amps and cold cranking amps (CCA) should be listed clearly on the label of the battery.
Weak or dead cell(s) are slightly conductive and will have a high resistance. Small currents will still flow through these cells. In this state each cell contributes little or nothing to the amp capacity of the battery.
6 cells @ 2.1 volts = 12.6 volts.
While a volt meter can read 12-13 volts on a battery with no load and a dead cell. As soon as a substantial load is applied the voltage will drop very low or to zero.
This is a surface charge
All 6 cells are needed to provide enough amps and shall have a low resistance.
Voltage is the measure of electrical pressure.
While Amps is a measure of the volume of electrical current.