Batteries, as you may have figured out by now, have a problem. A few problems, actually.

They don’t hold nearly enough power. That’s a real problem for phones, smartwatches, and electric cars.

They’re very expensive. That’s a real problem for the national electric grid, which desperately needs some kind of energy storage if sun and wind power are ever to become a thing.

And above all, they’re explosive. That’s a real problem for Samsung—and, actually, anyone who would rather not carry an envelope full of fire next to their thighs.

Isn’t anyone going to try to invent a better battery?

As it turns out, lots of people are. It’s a veritable space race to come up with the next great battery. How do I know? Because I’ve just spent a year interviewing them, as the host of a new NOVA special called “Search for the Superbattery.” It premieres this Wednesday night at 9 p.m. on PBS.

The good ol’ lithium-ion rechargeable battery is now 26 years old. It’s had its day.

Fortunately, I got to meet one man who’s breathtakingly close to cracking the powerful-cheap-safe battery problem. He’s a Tufts University professor named Mike Zimmerman, who runs a company on the side called Ionic Materials—and until our TV cameras entered his lab, he had never shown his invention to the press.

No more flammable liquid

Inside every lithium-ion battery on earth, there’s a positive electrode (the anode) and a negatively charged one (the cathode). They’re separated by a thin, microscopically porous sheet—a separator. And the rest is filled up with a liquid called the electrolyte.

View photos BASF explainer video More

When you charge the battery, positively charged ions flow through that liquid from the negative side to the positive side. Then, as you use the battery to power your gadget, they flow back again. (Here’s a good YouTube video explaining the whole thing.)

The key here is that electrolyte juice. It’s nasty stuff. It’s super flammable. Heat it up, poke it, introduce an impurity, or experience a short circuit, and you get what battery engineers call thermal runaway, which is what turns those Samsung Galaxies into fireballs.

What Zimmerman has done is pretty amazing: He’s created a battery that eliminates the liquid. In its place: A special plastic film, solid and not flammable. Yet it allows the free flow of the ions, just as the electrolyte does.

View photos The Ionic Materials battery is a sandwich—entirely solid. More

Zimmerman’s plastic doesn’t catch fire even if you try to light it with a grill lighter.

Zimmerman even encouraged me to cut the live battery. Into shreds. Down to nothing. No fire, no heat, no trip to the emergency room. And the LED light panel it was driving stayed turned on.

This is, in other words, a completely safe battery.

But wait, it gets better.

We call them lithium ion batteries because they do not, in fact, use actual lithium metal. That’s too bad, because lithium metal batteries can store at least twice as much power! The only reason we don’t use lithium-metal batteries is that they’re even more dangerous than lithium ion.

But if there’s no flammable liquid, there’s no risk of fire. So Zimmerman’s batteries do use actual lithium metal, and therefore hold twice as much charge. Imagine: Three days of life on every phone charge instead of one and a half. Four hundred miles in an electric car instead of 200. And so on. It’s a big, big deal.

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