Batteries taste sour because the hydroxide ions (formed as a result of electrolysis) activate the sour receptors. When you touch the lead of a battery, your saliva causes the electrons from one end of the lead to start moving to the other, creating an electric current. Also the electrons, on the way, interact with water molecules in a process called electrolysis, and gives out hydrogen and oxygen gases, along with hydroxide ions.
THIS IS COOL. I WANT TO LEARN SOMETHING ELSE, TOO!
Video via – SciShow
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ScienceSwitch 
I used to do this as a kid whenever I got hold of a nine volt battery. There just weren’t too many ways to get a thrill back then.
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Hehe but nice blog. The topic is great. Ya, you said right only curiosity can drive you to do that.
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LOL Am I the only one who doesn’t wish to taste a battery? 😉
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Unless curiosity drives you to 😛
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nope! LOL
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“Sour” is not the word I would think of, but I suppose it is the best one to describe the sensation
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Yup, that’s right! 🙂
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