modality - a method of therapy that involves physical or electrical therapeutic treatment. rehabilitation - the treatment of physical disabilities by massage and electrotherapy and exercises.
Alkaline AA batteries are rated 1.5 volts, while NiMH AA batteries are rated at 1.2 volts. NiMH generally refers to a battery being rechargeable and to the materials from which the battery is constructed.
This battery rating can be converted to energy if the average voltage of the battery during discharge is known. For instance, a 3.6-volt Lithium-ion battery rated at 850 mAh will maintain a voltage of 3.6 volts with little variation during discharge.