TEL AVIV (Reuters) - The head of an Israeli-backed electric car project estimated on Sunday that its partner, the Renault-Nissan alliance, would likely invest $500 million to $1 billion in the swappable-battery electric cars. "This is the cost for a three-year car program," Shai Agassi, the founder and chief executive of California-based Project Better Place, said on the sidelines of a news conference to introduce the electric car prototype.