A more reliable way to test a battery is when it is under load (drawing a large current). You can drive to an auto parts store and they can load test the battery.

1.Load Test with a fully charged Battery.
2.Fully charge the Battery and then check the specific gravity of each cell.

Both of the above assume Battery is "Topped Off" to correct fluid level with
DISTILLED WATER ONLY! Prior to Charging.

'For the purposes of this tutorial a fully charged Battery is one that has been
on a 2 Amp trickle charge for AT LEAST 36 Hrs.(SLOWER is always better).

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