Thin film graphite electrodes with low stress generation during Li-intercalation

We report here the development of thin film 'graphite' electrodes for Li-ion batteries, with near theoretical Li-intercalation/de-intercalation capacity (similar to 372 mAh/g). These films, synthesized by chemical vapor deposition at a relatively low temperature of 1000 degrees C, exhibit strong graphitic order with the basal planes oriented parallel to the Ni current collector. During galvanostatic cycling, in-situ stress measurements show that full lithiation corresponds to the development of only modest in-plane compressive stresses of similar to -250 MPa. These stresses are more than an order of magnitude lower than expected, which should promote long cycle life. (C) 2011 Elsevier Ltd. All rights reserved.