Scientists have developed a thin, flexible battery powered by body-friendly fluids – namely, saline (or intravenous) solution and cell-culture medium – that could be perfect for wearables and implantable medical devices.

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Scientists have developed a thin, flexible battery powered by body-friendly fluids – namely, saline (or intravenous) solution and cell-culture medium – that could be perfect for wearables and implantable medical devices.