Shortly after Stempel became chairman, ECD partnered engineered and provided the nickel-metal hydride batteries powered the EV-1. In 1999, ECD partnered with Intel in a joint-venture called "Ovonyx" which developed nonsilicon-based memory for electronic devices for Intel, Samsung Electronics and BAE Systems. Subsequently, ECD formed joint ventures with Texaco Energy Systems Inc., GE Plastics and Belgium-based N.V. Bekaert S.A. The promising technologies were unfortunately met with losses. Before retiring in 2007, Stempel was chairman of Energy Conversion for almost 12 years.