Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of electric vehicle maker Tesla Motors (Nasdaq: TSLA) zoomed as high as 12% in intraday trading after selling a $30 million stake to Japanese electronics giant Panasonic (NYSE: PC).

So what: Panasonic, which will acquire about a 2% stake in Tesla, said the two companies will combine efforts and sell battery packs for electric cars. Daimler and Toyota (NYSE: TM) have already made sizable bets on Tesla, so investors are taking the Panasonic deal as yet another powerful endorsement of Tesla's technology.

Now what: Tesla may eventually turn out to be a good green idea, but it seems too risky right now to get involved. While the recent big-boy buy-ins lend some credibility to Tesla's potential, the company hasn't been profitable since it was founded in 2003. With no real manufacturing experience and only 1,000 of its high-end cars sold, it's tough to envision how Tesla will ever have the edge over increasingly green-focused auto giants like Ford (NYSE: F) and Nissan.

Interested in more info on Tesla? Add it to your watchlist by clicking here.

Fool contributor Brian Pacampara owns no position in any of the companies mentioned. Ford is a Motley Fool Stock Advisor selection. Try any of our Foolish newsletter services free for 30 days.

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