What's inside a battery?

It depends upon what type of battery you are talking about. The common ones:
1/ Alkaline battery -- Used in Duracell¨ and Energizer¨ and other alkaline batteries. The electrodes are zinc and manganese-oxide. The electrolyte is an alkaline paste.

2/ Lead-acid battery -- These are used in automobiles. The electrodes are made of lead and lead-oxide with a strong acid as the electrolyte.

3/ Lithium battery -- These batteries are used in cameras for the flash bulb. They are made with lithium, lithium-iodide and lead-iodide. They can supply surges of electricity for the flash.

4/ Lithium-ion battery -- These batteries are found in laptop computers, cell phones and other high-use portable equipment.

5 Nickel-cadmium or NiCad battery -- The electrodes are nickel-hydroxide and cadmium. The electrolyte is potassium-hydroxide.

6/ Zinc-carbon battery or standard carbon battery -- Zinc and carbon are used in all regular or standard AA, C and D dry-cell batteries. The electrodes are made of zinc and carbon, with a paste of acidic materials between them serving as the electrolyte.
You could also argue that the human body is a battery. It stores and discharges electrical energy as well. I think I covered them all.

urine and boogers to make a paste and then the electricity travels through a small piece of plexiglass. This reaction powers the miniscule trolls inside the battery to run on their wheels producing your power.

Acidic acid i think its alkaline acid whatever you do don't attempt to open it. it will burn your skin

A PASTE THAT contains electrons

If you look at any battery, you'll notice that it has two terminals. One terminal is marked (+), or positive, while the other is marked (-), or negative. In an AA, C or D cell (normal flashlight batteries), the ends of the battery are the terminals. In a large car battery, there are two heavy lead posts that act as the terminals.
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