Yes they do make 9 volt batteries that are rechargeable. There is the Energizer Recharge, NiMH and the HiTech brand carries 4 types of rechargeable 9 volt batteries.
Run it all the way down until it's completely empty, and then charge it fully. Repeat a few times. You can also buy reconditioning units for most major brands. Success will generally be limited. You probably want to just buy a new battery.
Yes it runs on batteries. It uses 9 volt batteries. You can use either disposable or rechargeable.
9 volts (that's what the 9 means) Further Explanation: This sounds like a silly question, but a battery is not always at its' nominal voltage. In general, non rechargeable batterys of the same type will have a higher terminal voltage than rechargeable. Over time, as the battery becomes used, its' voltage will sag until it is no longer useable. Rechargeable battery cells are usually rated at 1.2 volts. When fully charged, they will be slightly more than this; as they age, they may become less. For cheap rechargeable 9 volt batteries, the manufacturer might use 7 cells - 8.6 volts; others might use 8 for 9.6 volts. Non rechargeable usually have 6 cells rated at 1.5 volts each (6 x 1.5 = 9).
First off, a battery is what you get when you stick several cells together, so for the most common 1.5 volts the strictly correct answer is that they are cells, not batteries. The 9 volt rectangular thingies though, they are batteries. Primary vs secondary is about rechargeable or not. A primary is not rechargeable, so a Duracell would most likely be a Primary cell.
No, a lead acid battery is a wet cell battery and a 9 volt alkaline battery is a dry cell battery.
No, the battery will be overcharged and battery damage will occur if it is done.
No
It heats up very hot and may explode.
All battery operated RC planes come with the highest capacity rechargeable batteries possible within the price range they target.For example a tiny RC plane might come with a rechargeable 9 volt battery.It'd only last ten minutes,but a normal 9 volt battery would be completely useless in the same plane.The only limitation is in the cost and weight.
no
A 9 volt battery is stronger than a 1.5 volt battery because it has a higher voltage. The higher voltage allows the 9 volt battery to power more demanding devices and last longer than a 1.5 volt battery.