The world???s most untradable stock has just gotten cheap again.

Sure, plenty of analysts have commented on the future of Tesla. But how many have taken apart one of their cars?

I have.

Concerns over the production ramp up for the new $40,000 Tesla 3 on which the company has bet its future is taking place slower than founder Elon Musk had hoped.

Only 1,500 Tesla 3's will be produced by the end of 2017. The goal is to churn out 500,000 a year by 2020.

That has given the shares an embarrassing 19% hickey, and another great entry point for traders.

The dozen manufacturers out there have long struggled to achieve ranges that could match the 300 miles that is standard for competing gasoline engines.

All electric cars on the market today max out at 100-mile ranges or less. Except, that is, my Tesla S-1 (TSLA), which can drive 305 miles....but for $80,000.

That is, unless I am driving back from Lake Tahoe.

By descending 6,200 feet the regenerative braking system enables me to add 100 miles to my range, increasing it to 350 miles. All four wheels essentially act as electric turbines.

In a research paper published in the prestigious journal Science, a Cambridge University research team announced a major breakthrough in electrochemistry that would lead to a 500% increase in electric car ranges.

Expressed in terms of the S-1, it would drop the cost of the 1,000-pound lithium ion battery from $30,000 to $6,000, shrinking the overall cost of the vehicle to $56,000.

That would enable it to undercut equivalent luxury models from Daimler Benz, BMW, and Lexus.

Alternatively, it could maintain the same battery weight and cost and boost the S-1 range to 1,450 miles.

Yikes!

The research was partially funded by the US Department of Energy.

Cambridge University retains the patent, and is already working with several firms to move the technology forward.

The great leap forward is made possible through the use of a lithium-air formula in battery construction. The basic chemistry of lithium-air batteries is simple.

The cell generates electricity by combining lithium with oxygen to form lithium peroxide and is then recharged by applying a current to reverse the reaction.

Making these reactions take place reliably, over many cycles, is the challenge.

The attraction here is that lithium air battery energy densities are ten times higher than the lithium ion batteries now in use.

The Cambridge team was able to tweak battery performance through adding lithium iodide to the process.

Elon Musk has told me that he is shown dozens of new battery technologies every year. The problem is always the same.

The newfangled batteries can only be recharged once or twice. They develop "tendrils" on the anodes and cathodes, which make future recharges impossible.

The Cambridge professor, Dr. Clare Grey, says her team has been able to recharge their lithium air battery 2,000 times.

That's enough to get to the eight-year battery lifetime guarantee mandated by the state of California.

Tesla is no slouch.

They have been tinkering with the electrochemistry of their batteries on their own.

The recent series of cars has achieved a 5% boost in range to 290 miles through the addition of silicon to the battery cathodes.

Of course, it will take a few years before lithium-air reaches full commercial viability. New technology doesn't exactly leap out of labs on to store shelves.

After all, current electric battery design is not too different from that first introduced in electric street trollies of the 1880's.

But my guess is that further research will bring greater battery ranges, not lesser ones.

The news could be better for Tesla. It has always been a "faith" type stock, reliant on the development of futures technologies to achieve future profitability.

All of the profits announced so far have really been accounting tricks, reliant on generous government subsidies and the sale of carbon credits.

Shareholders have to believe that Tesla will become the world's largest carmaker in a decade, or they shouldn't be in the shares. I believe Tesla can do it, but expect the road to be rocky.

Now, at last, we have the technology in hand.

For more background about this car from the future, read "16 Facts and 6 Big Problems I discovered by Tearing Apart my Tesla S-1" by clicking here.