How to check the voltage at which a battery, such as 1.5 V, 3 V or 3.7 V is not more energy an appliance?

power device that you should maintain in mind: question Woodley : How to check the voltage at which a battery, such as 1.five V, three V or three.7 V is not far more power an appliance I'm pleased simply because I guess that is how they decide experimentally (I know, the production offers this info for most batteries), which I feel is that in some energy, a% of original , which is normally not in the void, it will no longer supply sufficient electricity to power a device. As this threshold

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