Crystals.
CRYSTALS
Pierre Curie discovered piezoelectricty.
Crystals
Greek
4-10 dollars
Examples: tourmaline, quartz, Rochelle salt, topaz etc.
piezoelectricity
consider a triangle where each corner represents kinetic, electrical n thermal. the side bw thermal and electrical rep the pyroelectricity and it produces no kinetic The side bw thermal and kinetic rep the piezoelectricity and it produces no heat
when crystals such as quartz and Rochelle salts are squeezed or pressed ,they release electrons.This effect is known as piezoelectricity.
You are talking about piezoelectricity. See related linksbelow.
When piezoelectricity material is squeezed, it produces electricity. This is the esseantial idea about piezo materials.