Researched experimentally verified the “domino-cascade model” where local stresses within the material allow electrical and ionic conduction to spread from one area of the material to another, allowing the battery function. The results of this research could help in the search for improved battery technology and electrode materials and hasten the development of improved electric car and industrial batteries.

Lithium batteries are known to store three to four times more electrical energy per unit mass than traditional batteries have been used almost exclusively in portable consumer and industrial electronic devices. The materials utilized within Lithium batteries are very efficient and cost effective in mobile devices, however have shown to be too expensive for use within large battery application as required for electric cars and other vehicles.

CNRS chemists from the Institut de chimie de la matière condensée de Bordeaux (ICMCB) and their partners from CEA-Liten became the first to explain the “domino-cascade model” paradox. While studying lithium iron phosphate, they demostarted that the Lithium-ion battery's charge-discharge cycles are made by the "domino cascade process." This physics phenomenon occurs when stresses are present at the interface between the discharging material and the material in the discharged state. Ionic and electrical conduction then becomes extremely rapid at the interfacial zone, propagating from one spot to the next like dominos as the interface moves.

This reaction process, is best described as a wave sweeping through the crystal, and explains how the two insulating materials (one in the charged state and the other in the discharged state) can enable lithium-ion batteries function. This research could be an important step in the technical quest for new low cost and high capacity battery.

References:
Institut de chimie de la matière condensée de Bordeaux, ICMCB, (CNRS / Université de Bordeaux / ENSCPB).
CEA-Liten : Laboratoire d'innovation pour les technologies des énergies nouvelles et les nanomatériaux.

Journal reference:
Delmas et al. Lithium deintercalation in LiFePO4 nanoparticles via a domino-cascade model. Nature Materials, 2008; 7 (8): 665 DOI: 10.1038/nmat2230