I have a few 12V, 7.2 Ahr SLA batteries that have been sitting around and only charge up to a volt or so.
I suspect they may have sulphated. Is there any test I can do with a multimeter to confirm this? Or if they are otherwise incapable of being charged to full capacity?
Roy S.
Are you sure your charger is OK? Are you sure you didn't reverse polarity accidently?
When the voltage (no charger present) is that low, just dispose them according to your local rules. When you measure about a volt across the terminals during charging, they have short circuited cells. It isn't worth to invest time in them.
Best Regards,
Wim PA3DJS
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