How come my rechargeable battery self discharges so fast?

[meBigGuy]

When brand new, the cell has been self-discharging on the shelf for as long as it has been since it was charged at the factory. And, they may not have charged it to 100%. 1.27 volts is just what it happened to be at when you measured it. It has no meaning.

You need to fully charge it with a NiMH charger if you want to characterize it.

 

[grasscut]

You are placing too much reliance on that voltage. It's more of a guide for a typical cell. The best way to estimate a cell's state of charge is knowledge of the charge you have put into it, and it seems you are delivering minimal charge from your novel source.

When brand new, the cell has been self-discharging on the shelf for as long as it has been since it was charged at the factory. And, they may not have charged it to 100%. 1.27 volts is just what it happened to be at when you measured it. It has no meaning.

You need to fully charge it with a NiMH charger if you want to characterize it.

Thank you all for sharing. i think i need to find other source to verify. Since the source that i found is unsustainable.