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Tesla to buy battery firm Maxwell Technologies for $218m

Electric vehicle manufacturer Tesla has agreed to buy energy storage firm Maxwell Technologies for $218m, as part of an all-stock deal to help Tesla build better batteries.

Maxwell has developed tech that can help increase the driving range of electric cars while reducing the battery cost. Existing customers of the firm include General Motors and Lamborghini, while Tesla's exclusive battery cell supplier is Panasonic.

It also makes ultracapacitors, which discharge energy faster than regular electric car batteries. Maxwell claims they can lengthen the life of a battery by up to two times, and function across a broader temperature range.

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Tesla chief executive and tech billionaire Elon Musk had previously tweeted in 2013 that he had considered doing a PhD on ultracapacitors, but that the technology still had to make some scientific breakthroughs.

Tesla's offer values individual Maxwell shares at $4.75, meaning the firm is buying the battery company at a 55 per cent premium to last week's closing price of $3.07. Following the deal's announcement, shares in Maxwell surged almost 52 per cent, while Tesla's share price dropped as much as 3.3 per cent.

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Aside from producing electric cars, Tesla also sells power storage as part of its solar power business. 

Maxwell expects the deal to close in the second quarter of 2019, as it has already been approved by the company's board.