The Million Mile Battery

Lithium-ion batteries have been a regular part of our daily lives for the past 50 years. These batteries power almost everything—from phones and laptops all the way to vacuum cleaners and lawnmowers. Monitor technology, though, has taken them to another level. Now we can see these same batteries in bigger and better technology, most notably cars. These batteries are providing the world with a long-term solution when it comes to traveling, potentially removing the need for fossil fuel engines.

But lithium-ion batteries have one big problem: they really don't last that long. Typical lithium-ion battery packs only last 300 to 500 charge cycles, which already doesn't sound like a lot. After that, they lose the ability to hold a full charge. By then, only 80 percent or less of the original capacity remains. Over time, this capacity degradation will render the battery useless, and it will have to be replaced.

Why do lithium-ion batteries die out quickly? To understand this, let's look at how they lose their charge capacity. When the battery is charging, small structures called dendrites form on the battery. Imagine a broken mirror; it shatters completely. The cracks that form are essentially dendrites, and they look similar in a battery that's beginning to deteriorate. As the battery goes through charge cycles, these dendrites grow. As time goes on, they slowly begin to cover the entire battery, damaging its internal structure permanently. As a consequence, it loses the ability to hold a charge as well as it did before.

To keep it brief, the batteries die in devices where batteries can be easily replaced, like cameras, for example; it's not that big of a problem. But for those with non-removable batteries, like many phones, if the battery dies, the phone itself is essentially bricked—it's useless. Now, of course, the battery can still be replaced, but not without opening up the phone. It's a cumbersome and potentially dangerous process if you don't know what you're doing. One wrong move could destroy the phone entirely. Let's be honest; sending it in to get replaced is probably a much easier option.

Phones get replaced quite often, so if the battery dies, usually it happens when the phone is already dying itself. You would end up buying a new one anyway. But for bigger machines, like cars, you can't just buy a new one every year; this would get really expensive really fast. Sure, you can swap out the lithium-ion batteries in electric cars, but the thing is, these battery packs are truly massive, and each one costs a fortune to replace.

Let's assume you commute to work daily using an electric car. Well, obviously not right now, but you get the point. Assuming that you charge an electric car once per day, 500 charge cycles would be roughly one year and four months. Imagine having to have your car's battery replaced basically once a year. No one would opt in for electric cars, and gasoline engines would be preferred by everyone until someone figures that out.

Here's the thing about lithium-ion batteries: they really haven't been worked on much. Sure, the batteries have become cheaper while also holding longer and longer charges, but that's about it. The technology itself hasn't really changed whatsoever. Manufacturers are constantly improving lithium-ion; new and enhanced chemical combinations are introduced every six months or so. With such rapid progress, it's difficult to assess how well the revised battery will age, and so we're stuck with batteries that have lifespans of just over a year for now.

But will there be a way to change that? Scientists say yes. There's this field of science and engineering called nanotechnology. You might have heard of it; it deals with the science of really, really tiny things—the size of atoms. Nanotechnology has plenty of different applications, from medicine to advanced materials.

Speaking of which, advanced materials made a lot of good things for battery design. Tesla, the car manufacturer owned by Elon Musk, has announced that a battery with extraordinary longevity for electric vehicles is feasible and could be available in the near future. Tesla and many others call this the "million-mile battery." The name pretty much describes itself: a one million-mile-long battery.

Based on a study published in the Journal of Electrochemical Society, these long-lasting lithium-ion batteries are made possible by two things: special electrolytes and nano material coating on the battery's cathode or positive end. The electrolyte ensures that a charge flows smoothly across the battery, while the nano material on the cathode decreases resistance. In turn, the battery produces less heat and performs better overall.

But why is it a bad thing for a battery to produce heat? To illustrate this, let's take a trip back to 2016 when the Samsung Galaxy Note 7 was released. If you don't remember, during that time, several Note 7 users reported that their devices just spontaneously caught on fire. This was literally happening all over the world, which prompted Samsung to investigate. This is where they found the problem: the batteries were prone to overheating, which is what led many Note 7s to just blow up. So, in short, a hot battery is a fire and explosion hazard. But if that were to happen to a huge electric car battery, you can only imagine the damage it could do.

Now, back to that nano material coating on the cathode. At this point, a good question to ask would be: what is this nano material coating made of? Well, it's called nano-crystalline nickel manganese cobalt oxide, or NMC for short. You can say the whole thing if you want to sound smart. Anyway, synthesizing NMC takes a lot of time and energy, making it an expensive process. However, the Canadian startup company called Nano One was able to develop a technique that makes it less expensive to create this kind of material. Plus, Nano One claims that its patented manufacturing technique produced a single crystal and obscene, which packs more energy than traditional NMC. This allows a higher energy density than the traditional version, and this higher energy density makes them particularly suited to electric cars, which have much greater demands for power than small electronic devices.

The best part about this is that it prevents extensive wear and tear on the battery, which is the biggest concern we have. In turn, this means this kind of battery will last for hundreds or thousands of more charge cycles than a traditional battery would. If you were able to use this kind of long-lasting battery in an electric car, it would be the best option you could ask for. No longer do you have to replace the battery on an annual basis; once you buy the car, it could last you an entire lifetime.

A different innovation on lithium-ion batteries cooks nanomaterials on the anode or negative end. Researchers from Rice University, led by chemist James Tour, use materials called carbon nanotubes to coat the anode of a prototype lithium-ion battery. After subjecting the prototype to 580 separate charge cycles, they found that the batteries still retained roughly 99.20% of their electron flow efficiency. It had hardly worn down at all, whereas a normal lithium-ion battery would have been near the end of its life cycle. In simple terms, this kind of battery technology could produce a battery that lasts decades.

Alright, it looks like nanotechnology can solve the problem of battery longevity, but what about the issue of long charging times? Most lithium-ion batteries in electronic devices don't charge as fast as we want them to. I personally hate having to be confined to a two-foot radius around my electrical outlet when I'm just trying to use my phone. We normally have to wait 1 to 2 hours for our phones to fully charge, and if your phone is older, you might have to do this multiple times a day. Laptop batteries take more or less the same amount of time to recharge as phones, but for car batteries, like we've discussed, most of them take about eight hours or more to charge.

For most practical purposes, this means you'll have to leave it plugged in overnight to get the most mileage possible. For several years, lithium-ion batteries have been charging in pretty much the same way. While using higher voltages is possible to speed up charging, it isn't always the best solution. For one, charging at a higher voltage will degrade a battery a lot faster than charging at the standard voltage. This does more harm than good. On top of that, fast charging may generate excess heat, which, as we discussed earlier, is bad news for a battery.

So when will we see the day when batteries charge in minutes instead of hours, possibly even seconds? Well, I have some good news for you; the answer is probably yes, and guess what will make it possible? Again, it's nanotechnology. In 2014, researchers from Purdue University tinkered with the anodes of lithium-ion batteries. Usually, these anodes are made from graphite, which doesn't have a lot of energy storage capacity. So the Purdue researchers tweaked it and instead used tin oxide nanoparticles for the anode. They found out that tin oxide can both store more energy than graphite and charge much more quickly, taking only thirty minutes to complete a full zero to 100% charge cycle.

Another good thing is that these tin oxide nanoparticles aren't really difficult to synthesize; you could probably do half of it yourself. It only involves essentially cooking the raw materials called tin alkoxide in boiling water, followed by heat treatment. Afterwards, Professor Vilas Pol, one of the researchers on this project, said that the process can be easily adapted for commercial-scale manufacturing. So basically, anyone with enough money could produce these on a wide scale, and soon enough you may even see these batteries in the devices we use every day.

More recently, scientists from the University of Eastern Finland developed a hybrid anode composed of a mix of silicon microparticles and carbon nanotubes. Silicon has ten times the energy storage capacity of graphite, making these batteries even more powerful than the previous version we mentioned. On another note, IBM is onto something themselves, although it's probably not what you think. One of their projects is creating a battery with materials from seawater.

These materials have never been tried in a battery before. It doesn't even use the typical battery metals like nickel, cobalt, or lithium, but IBM says that this seawater battery can charge much faster, packs more energy, and is much less costly to manufacture than lithium-ion batteries. These qualities make IBM's seawater battery a perfect candidate for electric cars, and for that exact reason, IBM teamed up with Mercedes Benz and other car manufacturers to help develop a commercially viable electric car battery. But more of that in a future video.

All of these developments tell us one thing for sure: there is a bright future for battery technology. But even then, the big question remains: how soon will the million-mile battery arrive, along with these other innovations to make our lives so much simpler? As usual, I don't know. Neither Tesla, Mercedes Benz, IBM, nor the thousands of researchers from around the world mention any specific date. But personally, I feel that we can expect this technology to hit the market very soon.

Companies are always after one thing: money. Advancing battery technology is one thing that almost every company on Earth could benefit from. The first to do anything is always the one that is remembered, not the second. And I imagine that any massive company would be itching to get their name attached to this technology.

When that day comes, we can say goodbye to dead batteries in the middle of the day and hello to a future of automation, improved science, medicine, technology, and more inventions that will improve each and every one of our lives. I just hope that day is soon. Batteries are a big deal; they've revolutionized the way we work, play, and learn, but they're not perfect. They're far from it. Constantly improving our technology is the only way to build a future world that's better than the one we're currently living in. We need smart and capable people to help mold the future of society, and Brilliant is here to make that goal a reality.

Brilliant has over 60 online courses on everything math, science, and computer science related. If you want to learn more about batteries and the science behind them, I highly suggest that you check out Brilliant's course on electricity and magnetism. It's actually a field that I'm personally very interested in, and if you think you might be interested too, you would definitely benefit from checking it out.

What if science isn't exactly your thing? No problem; there's a massive catalog of interesting and challenging courses that are guaranteed to help you become a more educated individual. If you're interested and want to learn more, visit brilliant.org/aperture for a free trial. The first 200 of you to check it out will get 20% off a premium subscription, and it will allow you to take every single course that Brilliant has to offer.