(Yonggang Huang ) The small battery can be twisted up to 300 per cent from it's normal structure without breaking.
Future Bendable Batteries to Power Pacemakers and Bouncing Cell Phones
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FEBRUARY 27, 2013

A team of engineers have developed a new flexible battery that will pave the way for a number of medical and technological advancements.
By creating the small batteries so that they can be bent and stretched to an extreme degree, it will allow doctors to sew them directly into cardiac tissue.
Nature Communications also explained that the wireless power transmission system used for this type of battery will allow for these batteries to be charged without physical contact.
Read more: Daily Mail