What happened

Shares of electric-car company Tesla (NASDAQ:TSLA) jumped on Monday, rising about 9% by the time the market closed.

The stock's gain follows a pullback in the stock price toward the end of last week. Some investors may have thought drawdown on Friday created a good buying opportunity, helping drive a rebound in the stock on Monday. But there are other potential reasons for the stock's gain on Monday, including bullishness in the overall market and speculation that the automaker is going to build new and improved batteries at its factory in Berlin, Germany based on new technology.

Vehicle production at Tesla's factory in Fremont, California.

Tesla factory. Image source: The Motley Fool.

So what

It wasn't surprising to see Tesla stock moving higher on Monday. Highlighting positive sentiment in the overall stock market, the Nasdaq rose 1.7% by market close. Many growth stocks like Tesla were up even more.

But the automaker's stock may have also received a lift from a report that Tesla may be getting ready to make batteries based on new technology. Jorg Steinbach, Minister of Economics in Germany and "one of the main backers" of Tesla's new factory in the country (according to Electrek), says that the company will build a new battery with higher energy density, enabling longer driving range.

Now what

Steinbach told RBB24, a news website based in Germany, that Tesla will share more details on this battery at an event in late September.

The company does have a Battery Day event scheduled on Sep. 22. If this new battery really does come to market, investors may get more information on the technology and Tesla's plans for it during this event.