I would not buy any battery over 6 months old.
Most 9-volt batteries have an estimated shelf life of up to ten years. At the minimum, they will have a shelf life of four years. Most packages of 9-volt batteries will claim a shelf life of somewhere between seven and ten years.
if you mean shelf life they last for years if stored properly
The battery life (assuming it is a primary cell) is determined by the Ampere-hour drawn from it. You cannot connect a 3.5V bulb directly to a 9V battery. The bulb will fuse.
no, a 9 volt battery is small (goes in a smoke detector) a 9.6 volt battery is much larger, and it is not a DC battery (direct current) but NiCd (nickel cadmium.) two totally different things.
No
if it is any think over 1 volt it is not a cell battery it is just a 6 volt battery if you had a 1 volt then it would be a cell battery
No, it will overcharge the 6 volt battery.
The battery is a 12 volt.
No
Depends on the brand and model laptop. Can be anything from 10 to 16 volts. You must buy a battery that is specific to your laptop.
You get a 9 volt battery and u shock it
Charge the battery fully. That is all you can do.