Rechargeable batteries improved consumer electronics considerably, and as long as you take care of them as intended, you'll ...
How to Charge Your Phone Without Destroying the Battery Over Time ...
NiCd 1.2 Vdc 1.3 Vdc Constant current Temperature, or a timer NiMH 1.2 Vdc 1.3 Vdc Constant current, which can vary the charge time Neg. delta voltage, dT/dt (change in temp), or a timer Li-ion 3.4 to ...