The Race To Better Batteries

There is a new leader in the race to develop the best battery for smartphones, medical and IoT devices and all things related to information technology—Tesla.

After almost a decade of making a big splash in the auto industry, though hardly a dent in its business, Tesla has succeeded in making electric vehicles attractive enough that automakers are following Tesla into the EV lane. That move is being spurred by national policies in China, Europe and elsewhere that encourage or require automakers to offer more low-emission vehicles.

Globally, automakers say dozens of new or adapted models will be available as electrics. They have pledged to invest a total of $90 billion to design new models, adapt manufacturing plants and develop new technologies.

The influx is certain to create big changes in the market for batteries. But the first significant step may be to add a lot more manufacturing capacity to an industry that already has a glut, which will almost certainly create confusion over what battery technologies are available, what the next generation technologies will be, and when those will be ready.

IT equipment vendors and consumer products vendors have been both the leading consumers of lithium ion batteries, and the most frequent researchers into their weaknesses. But 26 years after they were first introduced to power Sony’s CCD-TR1 camcorder, they remain the industry standard.

A stack of patents and shelves of published papers shows how much work has been done on batteries. Nevertheless, technological development is much slower than pretty much anything else in the tech business.

“Battery performance for example energy density, has been increasing on average between 4% and 6% every year,” said AK Srouji, Principal Battery Scientist at Romeo Power, a battery technology manufacturing company based in in Los Angeles. “Applications with confined space, such as electric vehicles, have clearly benefited from that improvement.”

Alternatives to a lithium-ion battery have been in research for years. “You can build a battery with sodium ions or magnesium ions as charge carriers, but stabilizing the chemistry is not easy,” Srouji said. “It can take more than a decade to transition to a new charge carrier. Even within lithium-ion batteries, there have been many generations of chemistry. For example high-energy cathodes, composite anodes, and other components have been improving, in addition to multiple formats, but all high-performance cells are employing liquid electrolyte. One anticipated shift is toward an all solid-state electrolyte, which could improve energy density by up to 40% within its developmental period. However, there are many remaining electrochemical and manufacturing hurdles, and that shift could require as much as a decade.”

Small electronic scale solid-state cells with low power capability, primarily aimed at consumer applications, could begin showing up in the market within five years.

“The key enabling technologies are actually low-power radio chips and wireless,” said Mike Demler, senior analyst at The Linley Group. “There is always a desire for longer battery life, but the vendors and handset OEMs will just continue to pack in as many features as they can, live with the 4-watt to 5-watt power budget, and depend on the popularity of larger screens to squeeze in larger batteries if they need to.”

Fig. 1: Li-ion battery market. Source: Frost & Sullivan

Why Li-ion?
Lithium ion has dominated the market for electronics because its light, energy-dense, holds its charge well, and shows minimal memory effect. It’s not the kind of thing a whole industry normally works that hard to escape.

Most other analysts expect to see li-ion in approximately its current form, stick around as the default option for energy storage for at least three to five years.

“Solid state is coming for sure, but probably not within the next five years” said Olivier Nowak, analyst at IHS Markit. “That would be a big deal. Everyone wants longer battery life, but existing Li-ion batteries are not such a terrible solution for mobile IT, barring the occasional fire. The geometry and mechanical design of batteries is already quite flexible and, barring an unexpected breakthrough in solid state or something else, I don’t see any big change happening right away—not coming from the mobile IT world, anyway.”

Oddly enough, the physicist who invented Li-ion is more unhappy than most with the rate of density improvement. “You need something that will give you a bit of a step, not an increment,” John Bannister Goodenough told Quartz in an interview about his own “superbattery” alternative to li-ion.

Goodenough finished the basic design using a lithium-cobalt-oxide cathode at Oxford University in 1980, but Oxford declined to patent it. Goodenough won a Medal of Freedom in 2011 to honor his invention, but received no royalties on his work—despite the fact that it has been powering the digital world for two-and-a-half decades. But he’s back, at age 94, with a paper describing a solid-state battery he claims is non-combustible, has a long lifecycle, a fast rate of charge, and a 10-fold improvement in energy density. His device is made with a glass electrolyte and pure metallic lithium or sodium on each side of the electrolyte.

One colleague called its performance “anomalous capacity,” because the setup shouldn’t generate any power at all.

“We haven’t violated any laws of thermodynamics,” he told NPR, “and we have tested it and we have proven we can get 3 volts over 500 cycles,” he says.

Goodenough described the battery in two papers (here and here). Now, along with physicist and co-author Maria Hela Braga, he is “waiting for some battery company to come along,” to license and test the battery, he told BNEF.

Spray-on solid-state battery
Solid-state batteries have been the talk of the battery industry for years. They are stable, high power, and very, very hard to achieve because they have to be able to get lithium ions to cross a solid wall, rather than a welcoming liquid-electrolyte interface, according to Farid El Gabaly, a physicist at Sandia National Laboratories.

El Gabaly recently published the result of three years of study where an electrode touches an electrolyte, to try to make sense of the result.

El Gabaly and a colleague used X-ray photoelectron spectroscopy, along with electrochemical techniques, to study how easily and quickly ions could slip through from one cathode through a solid interface to the other cathode.

“No one had observed these materials at the interface before at the relevant state, and there were many processes that would make the ion move more quickly or slowly,” El Gabaly said. “We were looking at the interface of the batteries at angstrom resolution to see what we needed to change to make an improvement.”

Knowing exactly what slowed an ion in its trip to the opposite node should make it possible to make that passage easier or harder to get better control over processes without having to watch them in a microscope.

“If you understand the kinetics, it makes it so that, if you want to discharge the battery all in five seconds, you can do that. Or if you want to charge it in one minute, you know how to get the ions to do what you want.”

The project focused on small solid-state batteries the researchers had to create themselves by painting the material on in layers just a few molecules thick, one after another, until the battery is complete. The technique will eventually be used to add sensors, logic, a wireless capability and other elements, all powered by a permanent solid-state component installed on the on the chip as a kind of SOC, but integrated with the power integrated into the piece from the beginning.

Given how hard it is to get a solid-state battery up to a high level of performance, El Gabaly expects his approach won’t get out to the public for at least three to five years.

“The current batteries are fairly stable,” he said. “Waiting for something better shouldn’t be a problem.

Conservative pace
The emphasis is on the words “fairly stable,” because there have been enough high-profile battery fires caused by lithium-ion batteries to raise serious questions about what comes next.

Among the problems:

• The Samsung Galaxy Note 7 achieved such notoriety that U.S. airlines banned the phone, forcing a recall of the phone. Credit Suisse estimated last year that the problem could cost Samsung $17 billion. Industry sources say the fires were the result of a faulty spec at one of two battery factories used by the vendor. As batteries charge and discharge, there is swelling in the electrodes, but a missing radius of curvature allowed the foil on the positive and negative electrodes to touch, which caused overheating.
• Boeing’s new 787 Dreamliner was sidelined in 2013 after several airlines reported smoke and fires stemming from lithium ion batteries. The problem in that case was that battery contracts were signed in 2005 for lithium cobalt oxide batteries. Those have since been replaced by lithium manganate batteries, which are safer.
• In November, the U.S. Consumer Product Safety Commission said it was aware of more than 250 hoverboard incidents related to fires or overheating since 2015. The warning affected roughly 14,000 of the devices.

What’s key here isn’t that the technology is slow to progress. It’s that minor errors can cause big problem with batteries, transforming even everyday devices we take for granted as toys or electronic tools into safety hazards that can cause injury or death.

“Building high-performance fully functional and integrated battery systems, using a multitude of single batteries at mass scale to achieve performance, quality—and most importantly, safety—is essential,” said Romeo Power’s Srouji. “There is vertical optimization work done, from knowledge of battery particle behavior to the required performance at the vehicle wheel, or the grid terminal.”

Conclusion
Progress in batteries will continue, but there is more to this picture than just the chemical composition of the battery components. It’s also about the cell, module, and system design, design to make sure that if one battery goes into thermal runaway, the heat does not propagate to neighboring cells, in addition to achieving the application required cycle life, and calendaric life. And it’s about the designs of the electronics themselves and how they utilize the energy from batteries, whether that is in burst mode with rapid recharge, or whether it is a steady flow of energy and a long recharge cycle.

Batteries increasingly are part of an energy ecosystem for any device, and that is prompting a new wave of investment and research in battery technology from startups, universities, and established giants such as Tesla. As more processing power moves to edge nodes, more devices will be required to do more using energy stored in batteries than ever before. That will require changes on multiple levels, both inside and outside the battery.

—Ed Sperling contributed to this report.

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