I have a 6 volt 4.5 mah SLA battery.
I have been charging it for 10 hrs. at 500 ma.
The battery powers (2) 1000 lumen lights for my bicycle.
When I powered up the lights, they are pretty dim.
Is there a load test I can do to see if the battery is dead ?
Thanks, Andy
I assume they used to be lit brightly by this same battery?
I think you have done it. What are the voltages on the battery when you charge it, when nothing is connected and when the lights are on it?
You need to test the battery voltage; if it is 6V nominal, it should be 6 to 7V fully charged with no load, and 6V or so with a 500 mA load (like, a bicycle headlamp). From your charge regimen, I'm assuming the battery is a 4.5Ah battery (ampere-hours, not mAh, milliamp-hours).
6.72 volts with no load.
I will check it with a load.
Andy
if it was 4.5mAh it's dead now!
Just making up some numbers...
2000lumens at 100 lumens/watt = 20 watts/6V = 3.something amps. This assumes that the lamps really are 2000 lumen. Most reviews suggest that most lights are way less than advertised brightness.Factor in some inefficiencies and call it 4+ amps. You need a bigger battery.
Depending on how long you want the lights to run, you won't be happy with any lead-acid battery.
Just measure the volts with the lights on and off.
measure v drop on the wiring, measure terminal voltage on and off load.
NT
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