Testing a battery requires two known values. The AMP capacity and static voltage.
A required tool is a hydometer.
The valves on the hydrometer represents the weight of the electrolite of each cell.
What you want to do is make sure that battery has not been charged for approximatly 8 hours. The reason for this is that during charging, gas is emitted in the form of bubbles. The bubbles will cause a false reading of the float in the hydrometer.
8 hours should be enough time for the bubble to disapate.
When using a hydrometer, you also need to make sure the batteries are not near dead or completely dead. The reason for this is that when the batteries are completely dead, the gravity of the electrolyte will all be the same, dead or discharged.
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