Engineering

Lithium (medication)

Metallurgy

Materials science

Cathode

Planar

Computer graphics (images)

Endocrinology

Computer science

Physical chemistry

Thermodynamics

Physics

Diffusion

Crystallite

Cracking

Manganese

Composite material

Fracture (geology)

Cobalt

Medicine

Chemistry

Nickel

Forensic engineering

Science

Cracking the problem of cracking cathodes Polycrystalline cathode materials that contain a combination of nickel, manganese, and cobalt have been used for advanced lithium batteries. These materials fracture at high voltage, which increases surface area and leads to more side reactions and shorter cycle life. Using single-crystalline samples as model materials, Bi et al. observed changes in nickel-rich cathodes to study the fracture behavior under well-characterized conditions. As the material is charged and lithium is removed, specific planes glide over one another and microcracks are observed. However, this process is reversed on discharge, removing all traces of the microcracking. The authors developed a diffusion-induced stress model to understand the origin of the planar gliding and propose ways to stabilize these nickel-rich cathodes in working batteries. Science , this issue p. 1313

Reversible planar gliding and microcracking in a single-crystalline Ni-rich cathode