Why does an AA rechargeable battery have 1.2V whereas a once-use have 1.5V?

Question

all answers appreciated =D

Answer 1

The 1.2 volt rechargeable batteries are ni-cad or nickel cadmium . The 1.5 variety are zinc carbon or alkaline manganese .

Cheers Pete

Answer 2

its nothing to do with usage!

its that CHEMISTRY of the batteries are different! use once are either basic Zinc carbon or Alkaline Managnese based. and the electropotential of the ingredients are built to produce around 1.5 V.

this is beacuse the 1.5 V standard was created from old lead acid batteries and Zinc Carbon was used because it was the nearest voltage. but alkaline single use batteries also have a voltage lower than 1.5V.

with rechargeable batteries the device is often designed to have a power suply and so can charge them also it can be made to use a lower voltage input which results in better power uage of the.

if you want more information go to http://www.varta-microbatteries.com  

Answer 3

Well the only reason i know is that a rechargeable battery if used multiple times will lose some of its capacity to store electrical energy through using it and recharging over and over. Whereas a normal non rechargeable battery (also depending on brand etc) will have a more optimum power and since its used once the makers made it to give the best output as possible, but with the rechargeable they had to make it give the best output and make it last long though there is a  loss of capacity through use and re-use.