The alkaline batteries are named such because they have an alkaline electrolyte of potassium hydroxide
. These batteries are the type of disposable batteries or rechargeable batteries that depends on the reaction between zinc and manganese oxide (Zn/MnO2).
These batteries produce a nominal voltage of 1.5 volts per cell as compared to zinc-carbon batteries. Multiple ranges of voltages can be achieved with the series of cells. Depending on the choice of manganese dioxide and the amount of zinc oxide in the electrolyte, the effective zero-load voltage of a non discharged alkaline battery varies from 1.50 to 1.65 Volts. The average voltage under load depends on the discharge which varies from 1.1 to 1.3 Volts. The fully discharged alkaline battery produces the voltage in the range of 0.8 to 1.0 Volts.
They also have higher energy density and better longevity. The alkaline batteries which are competing against in button cells have lower energy density, shorter life span and low cost when compared with silver-oxide batteries.
With respect to current, the alkaline battery can produce the current depending on its physical size. This is due to the decrease in the internal resistance with the increase in the internal surface area of the cell. Normally, the AA alkaline battery can generate 10000mA of current without any heating whereas, the larger cells like C and D cells can produce more amount of current. So, the applications such as high powered flashlights, portable stereos which require high amount of current requires D-sized cells to handle the increased load.