Elon Musk discusses future of battery technology

Tesla CEO Elon Musk has been discussing the central importance of batteries to the company’s future. Speaking at Vox Media’s Code Conference, Musk explained that the energy density – the measure of the energy held by a battery – of Tesla’s batteries is increasing by almost 5% each year. The higher the energy density, the longer a battery can run. However, Musk’s main aim is to reduce the cost per unit of energy used in batteries. This, in turn, will lower the cost of Tesla’s cars. The ultimate goal is to produce a car with a long range that can be sold at an affordable price. Musk drew a comparison with mobile phones. Large economies of scale in that market meant that everyone could "have a supercomputer in their pocket."  

Patrick Fallon / Reuters

Batteries aren't exactly the most interesting thing to talk about, but Tesla CEO Elon Musk put into perspective the important role they will play in Tesla's future.

Speaking at Vox Media's Code Conference on Wednesday night, Musk said that the energy density of its batteries is increasing on the order of nearly 5% per year, which ends up being a "significant number" when added up over a number of years.

Energy density is a measure of how much energy a battery can hold, so having a higher energy density means having a longer battery run time.

"A lot of people think we cobbled together some laptop batteries and made a car, but it's a lot harder than that," Musk said. "If it was that easy, I think we would have quite a few competitors who did the same thing."

But Musk said that energy density really isn't an issue for Tesla. He's so confident in that that he said Tesla could make a car with a 400-mile range today.

Yet what Musk really wants to do through his massive battery plant, the Gigafactory, is decrease the cost per unit of energy of battery packs. Put more simply, decreasing the cost of Tesla's batteries will make its cars more affordable.

This isn't the first time Musk said that his real goal is on making more affordable electric cars. The Model 3 is Tesla's first stab at affordability with a price tag of $35,000 before federal tax exemptions. And in a recent conversation with Norway's minister of transport and communications, Musk said that "there will be future cars that are even more affordable down the road."

Tesla is putting its energy — yes, pun intended — in batteries so it can make the electric vehicle of the future: a car with a long range at an affordable cost.

He likened it to cellphones, which have gone through so many design iterations and have such a large economy of scale that everyone can "have a supercomputer in their pocket."

Battery breakthroughs could be what makes Tesla the iPhone of electric cars.