<p>In this work, online charge management of electric vehicles spreading in a large area that has communication problems with the exchange of information. We use the idea of clustering to divide the electric vehicles population into several smaller groups as in parking lots with a local aggregator and local information exchange. Due to the uncertainty in the number of vehicles in each group and also power consumption and generation, the smoothness of the grid load curve is disrupted. To address this problem, we propose an online optimization based on the receding horizon concept. However, due to the increasing of online calculations, the optimization is performed in an event-triggered scheme according to the situation and information obtained from the grid monitoring. The results can be brought closer to the online method by sensitizing the trigger condition. Our approach has shown significant improvements in addressing this issue. We provide computer simulations to illustrate the effectiveness of the proposed event-triggering method.</p>