Huge infusions of money would seem to have helped Tesla Motors: the electric-car startup has escaped a bitter lawsuit from founder Martin Eberhard and finally sited a power-train factory — and that's just this week. But other fights loom.

Eberhard has suddenly dropped his suit, the San Jose Business Journal reports. It seems safe to assume some sort of settlement was reached; the $465 million in federal funds Tesla received from the Department of Energy after Eberhard filed could have freed up other cash for a payout, or convinced Eberhard that Tesla had the resources to mount a protracted fight. Or maybe Tesla was simply scared: it just lost a preliminary motion to throw out the case.

Tesla's money also helped it secure land in the Stanford Research Park, not far from Facebook's new headquarters, replacing a San Jose parcel it had planned to acquire but lost in January thanks to its lack of capital.

Now the company can turn its attention to the real challenge: Fighting off Nissan, which just rolled out its "Leaf" electric car, which it plans to introduce in 2012. Nissan, which will lease the battery pack separately, has said its car will compete with gas-powered vehicles costing $25,000-$30,000. Tesla CEO Elon Musk, meanwhile, has staked his company's future on the Model S, which is a full-sized sedan to the compact Leaf but starting around $50,000. In addition to an apparent price gap, Tesla must also wrestle with the recent departure of its science director, in charge of the critical battery system. And it must site and build a factory to manufacture the S itself.

Like most startups, Tesla has been through its share of booms and busts. Right now it's on a roll; the question is whether it can build up enough momentum for the inevitable crash back to reality.

[lawsuit news via Business Insider]