Calcium, a much more abundant and cheaper element than lithium, can act as negative electrode in rechargeable batteries. This is shown in a study elaborated by researchers of Spanish Research Council (Consejo Superior de Investigaciones Científicas –CSIC) at the Institut de Ciència de Materials de Barcelona (ICMAB) in collaboration with Toyota Motor Europe (TME), and with the support of the results obtained at ALBA Synchrotron.
This study proves that calcium can be used as negative electrode in rechargeable batteries of high energy density and that they are compatible with electrolytes commonly used in lithium ion technology. These results are the basis of two filed patents and from now on researchers will direct their efforts to the development of materials for the positive electrode able to operate at a high potential to achieve high energy density batteries.
Fig.: Scheme of the calcium battery (left), electron microscopy image (right) and powder diffraction pattern of the developed electrodes (below).
This work has been possible by combining different techniques, including electron microscopy and synchrotron powder diffraction, among others. The latter was done at the BL04-MSPD beamline at ALBA Synchrotron and allowed to unambiguously prove that the electrodeposits achieved in conventional electrolytes consist partially of calcium metal.
This research, which has been published in Nature Materials (Ponrouch et al., 2015), opens the door to future technological applications of calcium in the development of batteries.
