"Yolks" and "shells" improve rechargeable batteries

"Yolks" and "shells" improve rechargeable batteries

Aluminium could give a big boost to capacity and power of lithium-ion batteries
(MIT News)

During every charging cycle, the insides of a lithium-ion battery expand and contract, putting wear and tear on the battery, which erodes its effectiveness over time.  Hence why your mobile phone constantly needs to be recharged.

Researchers from the Massachusetts Institute of Technology (MIT) and China’s Tsinghua University may have solved the problem by creating an electrode made of nanoparticles with a solid shell and a “yolk” inside that can change size again and again without affecting the shell. 
 
The full article can be found at MIT News.
 

Image:  Christine Daniloff/MIT
The gray sphere at center represents an aluminum nanoparticle, forming the "yolk." The outer light-blue layer represents a solid shell of titanium dioxide, and the space in between the yolk and shell allows the yolk to expand and contract without damaging the shell. In the background is an actual scanning electron microscope image of a collection of these yolk-shell nanoparticles.