A look inside the world of batteries

24Jun 2019

You are an entrepreneur. You understand that batteries are powering the future. You think present battery technology falls short of market demands. You invented a new battery technology. You may even have some early prototypes that show some exceptional promise. So you start a new company to commercialize your new technology. Welcome to the Battery Gold Rush, ca. 21st century.

In the first Gold Rush, ca. 1849, many made fortunes, and many others lost riches. The new Battery Gold Rush will not be much different. So what factors should you be thinking about in your pursuit of the battery holy grail?

I will assume here that your battery technology is exceptional.You have tested it. It works in the laboratory. What I will address here is whether you and your investors will make money in this endeavor.

Five factors require consideration.

  • Are the economics of the battery market in your favor?

As a young graduate student several years back, I was constantly advised to move my thesis work away from silicon to gallium arsenide (GaAs). Known as III-V compounds for their position in the periodic table of elements, these new materials offered immensely better performance than silicon integrated circuits. Yet today, silicon dominates the semiconductor landscape simply because its economics far outweighed the economics of any other competing material system. There is a lesson here for emerging battery technologies to be economically viable from the get go.

As batteries increasingly become the energy source powering everything from smartphones to electric cars, one key economic metric to pay attention to is $/kWh: the cost per unit of energy stored within the battery. For the big manufacturers in Japan, Korea and China, the cost metric stands today somewhere between $100 and $150 per kWh.  It is forecasted to drop below $100 by 2025 at which point the cost of an electric car is equal to that of a traditional combustion engine vehicle. 

If your technology increases this cost, or your business model is based on a significant premium, then you are at risk of serious commercial headwinds. It does not mean that you will fail, but it means that the adoption of your products may be limited to niche markets, or that the rate of adoption may be too slow for your company to reach profitability.

  • Are you sure you have a working business model?

Most battery startup companies are exploring a wide variety of business models. Some favor building the entire battery. Others feel that manufacturing the materials are sufficient. A few others are content developing the technology and selling its underlying intellectual property. Which one is better? You will need to quickly validate the business model for yourself. 

If you choose to build the entire battery, will you be able to scale your manufacturing and distribution fast enough? Will you have the investment capital required to compete with the incumbents? Ramping up a battery manufacturing operation could cost in the billions of dollars. History has not been kind to battery startups. The rise and fall of A123 Systems is a business case worthy of serious study.

If, instead, you decide to build your business model on selling materials, your customers are now the battery manufacturers, the  vast majority of whom are based in Asia. Your technology may be differentiated but your customers are also your competitors. How will you protect your intellectual property? Will they pay you what you think is the value of your innovation? History also has not been kind here too. You will need to think out of the box to experiment and identify a working solution to the business model dilemma.

  • Will your product scale?

I have seen many amazing demonstrations in the laboratory of innovative battery materials. It is truly exciting to see this degree of innovation. But I am not aware that any of these recent battery material ideas have made it to volume production, at least not yet. As companies begin to ramp up manufacturing, many problems rear their ugly head. Uniformity of manufacturing across lots; meeting specifications on larger batteries; cost overruns; scarcity of available capital; investor fatigue are only a few examples of headwinds.

  • Do you understand your “exit” opportunities?

Your capital comes from investors who have an expectation of returns. A return of 5X or more is considered good; 10X or more is considered great.  So if you company requires $200 million to $500 million of capital to reach some degree of scaled operation (and hopefully profitability), then the expected “exit” valuation of your company is in the range of $1 billion to $5 billion. Congratulations if you achieved these valuations in your recent fundraising round. Very few companies can achieve this milestone. But will a potential buyer pay these valuations to acquire your company? Most incumbent battery companies in Asia have shown serious hesitation paying such valuations. You might, instead, choose to take the path of an initial public offering (IPO). A123 is such an example. But be careful, public markets have not been kind to company valuations with poor margins and tepid growth trajectories. In any case, the “exit” path — i.e., how you and your investor will turn your shares in the company into cash — is not well charted for battery companies. There are no easy precedents to follow and the path is fraught with incumbents who might choose to wait for you to reach desperation.

  • What about the Dragon?

China is rapidly becoming the battery manufacturing powerhouse. It means that Chinese battery manufacturers will likely be customers or partners of your company, or even potentially acquirers. Given the geopolitical tensions between the USA and China, it is difficult that the US Government will authorize the transfer of your technology or products to China under the export reform rules of the Defense Authorization Act of 2018. Will you choose to build your company anywhere else, may be in Europe or other geographies that will allow you to work with China? If so, you will need to figure that out early on in your endeavor.

My intent here is not to scare you off. The battery industry is in need of innovators. But innovation alone is not sufficient. Reaching financial success is essential to you, your employees and your investors. 

08Apr 2019

Let’s say you love to ride your bicycle and that you want to measure speed without using fancy computers and GPS. What would you do?

High-school physics to the rescue! All we need is the circumference of the wheel then count the number of rotations the wheel makes in a certain amount of time that we can measure with our stopwatch. The speed, v, is calculated as the number of rotations, N, multiplied by the circumference, L — that’s the total distance traveled by the wheel — divided by the measured time, T. Put in one simple equation:

We replace the circumference with the radius, R, because it is easier to measure the radius of the wheel:

The speed equation becomes:

Therefore, measure the wheel radius, then count the number of rotations, and clock them with a watch…et voila, you can measure speed.

You quickly realize that you have an approximation of speed because it fails to take into account other factors that can introduce errors, for example temperature. On a hot day, the wheel expands a little making the radius longer.  Then you realize that the thickness of the rubber tire is not exact — it varies across manufacturers. With aging, the rubber gets worn out. It becomes thinner and consequently the radius is a little smaller. You may think these are small effects but if you are racing, they can make the difference between winning and losing.

So what is the relevance of a bicycle wheel to a battery?

Scientists understand the electrochemistry inside a battery.  They represent this science with many complex equations — like Fick’s law, Tafel’s equation, and several other mathematical forms. Yet, these equations remain insufficient to describe batteries in real life. 

Much like the wheel, there are significant variations in manufacturing across batteries from the same manufacturer or from different manufacturers. Temperature dependence, aging, presence of defects…etc. are significant additional considerations that impact the performance and safety of the battery.

Capturing these “real-life” considerations is what makes a model of the battery useful.  By “model” I mean a sufficiently accurate representation of the battery that one can use to make meaningful conclusions. For example, a good model can be used to predict the end of life of the battery. It can be used to identify counterfeit batteries or find defective batteries before they become a fire hazard.

Developing the model entails collecting data — millions of measurements — to capture manufacturing variations, temperature dependence, defects…etc. It takes a long time to collect statistically meaningful data across different types of batteries, from different manufacturers and across a board range of operating conditions.

The battery model is not static — it must improve over time or it becomes obsolete. One must keep updating it so it learns and adapts to newer battery materials, newer battery designs and manufacturing processes. This learning process can be in the test lab, or it can be in the field — in other words, intelligent algorithms can learn from batteries deployed in smartphones or other devices already in the hands of users.

Possessing intelligent algorithms and useful battery models is a powerful combination to make key predictions about the battery’s health and safety…that can make the difference between a safe battery and a fire.

19Feb 2019

Some time in August of 2013, hackers breached Yahoo! servers and stole private account information for up to 3 billion users. Verizon Communications received a $350 million discount in the price of its acquisition of Yahoo! in 2017, exemplifying the staggering costs of one single encounter with cyber risk.

The concept of risk and risk management is not new. In 1688, Edward Lloyd set up what would become today Lloyd’s of London to contain the emerging risks of the new and growing maritime trans-Atlantic trade. Since then, the business world has worked diligently to contain such risk in everything from food to the Internet.

Actually, almost everything. One such modern risk that remains inadequately addressed is battery safety, specifically the safety of lithium-ion batteries that are so ubiquitous. To be fair, industry has recognized long time ago the safety hazards surrounding the lithium-ion battery. Battery fires in the early 2000s caused expensive recalls. But they were largely treated as one-off events. These were times when the annual volume of batteries was a few hundred millions. These fires were not treated as an on-going risk. They were seen as failures in manufacturing that could be eliminated by improvements in factories or designs.

Today’s battery shipments have skyrocketed to billions of units and counting. Even a minuscule chance of battery fire becomes a real problem when multiplied by the sheer volume of batteries. Battery failures are an ongoing risk that needs to be contained.

Estimates place the risk of battery fire in the range of a few to tens of parts-per-million (or ppm). One ppm means that for every one million units shipped, there is a risk that one of them will catch fire. It does not mean that one *will* catch fire. It just means that statistically speaking, the probability of a fire is one in a million. Now that seems like a small number. You might tell a precious love that they are “one in a million.” In an industry that ships two billion smartphones annually, that translates to several thousand battery fires annually! Not acceptable! We need to bring this figure down by a factor of 100 or 1,000.

Edward Lloyd’s business was possible because it had its underpinnings in the mathematical advances of probability pioneered by Blaise Pascal and Pierre de Fermat early in the 17th century. In that same vein it is possible to make great improvements in battery safety because it leverages the advances in computation of the past 50 years.

Every smartphone is a miracle device. It contains a processor that is infinitely more powerful than the computer that landed Apollo 11 on the moon. It also contains sophisticated electronics that can measure minute voltages and currents, and in turn it is very telling of the chemical reactions inside the battery. Merge it all with intelligent software, and we can now predict what the battery’s health will be in the future.

But why can’t we just manufacture the perfect battery that will never catch fire? Simply put, it is prohibitively expensive. Consider this: nearly every person with a smartphone is also an amateur photographer. Despite the fact their camera lens is optically deficient, software allows them to take incredible photographs.

The same goes for batteries. Manufacturing batteries in large volumes means that some will have defects. That’s just the balance between quality and cost when it comes to battery manufacturing in large scale. To make matters more challenging, every person will use or abuse their battery in unpredictable ways. It becomes essential to catch and screen these few bad batteries in the field before they become a hazard. Naturally, this is not meant to supersede good manufacturing practices, but rather to complement them in our quest to reduce battery fires to zero.

So how does it work? I talked in the past about electrochemical impedance spectroscopy (EIS). It is a workhorse test instrument in battery laboratories around the world. It is capable of measuring the chemical processes that are taking place inside the battery. Now imagine if you had such a similar tool inside your device. With some expertise, you can now start making smart decisions about your battery. This is not a new concept; a similar concept, for instance, allows glucose measuring devices to save the lives of millions of diabetics.

It’s high time we get serious about battery health and safety. Let’s address this risk before it escalates. The spread between device capabilities and battery threats is only growing — let’s get smart and manage potential incidents before they blow up into something bigger.

15Feb 2019

Everyone’s excited about 5G. And with good reason. All the great things we have been able to do on our smart phones with 4G LTE will multiply into bigger and better things in the 5G Era. We’ll be able to send and receive huge text and image files in the blink of an eye. Entire movies will download in seconds. In short, 5G will make our smart phones vastly more useful as business productivity tools and as entertainment platforms. I don’t know about you, but I can’t wait.

There’s just one thing. The excellent experiences of 5G can’t happen without battery power.

Unfortunately, batteries are a major stumbling block of the smart phone era. Explosions and fires, although rare, are a serious problem. One such mishap is too many.

A little history: Introduced commercially in 1991, lithium-ion batteries are a tremendous advance over previous-generation technology, such as nickel-cadmium and nickel-metal hydride, and they have made the 4G LTE era possible. But in the 5G era, lithium-ion batteries risk being exposed as the weakest link in the chain of 5G-enabling technologies.

This looming catastrophe is no secret. Smart phone manufacturers and network operators I speak with are concerned about 5G and the demands that will be placed on handsets. They know something must be done. But what?

Researchers are working night and day to come up with breakthrough battery technology, such as solid-state batteries or batteries using nano materials. But battery breakthroughs often take a decade or more, and billions of dollars in investments. Much more work needs to be done before these next-generation batteries are ready to be deployed in large volumes. Realistically, we need to accept the fact that 5G will dawn on smart phones equipped with lithium-ion batteries. The only sensible approach is to get those batteries as ready as they can be for the new era.

Briefly, here’s the issue: Every battery has a cathode and an anode, in a substance called the electrolyte. During charging, ions move from the cathode to the anode through the electrolyte. In lithium-ion batteries, tiny tree-like growths called dendrites may form on the anode over repeated charging cycles. These dendrites can grow so large that they eventually reach through, touching the cathode and causing an electrical short, possibly leading to an explosion or fire. Dendrite formation is accelerated by factors that stress the battery, such as rapid charging or overcharging. Damage caused by these stresses accumulates over time.

5G will put stress on batteries as never before, thanks to several factors:

  • The higher-frequency bands of 5G require more power. 5G encompasses new frequency bands of 3 GHz to 6 GHz and above 24 GHz. Power consumption increases linearly with frequency, so going from 900 MHz to 6 GHz, for example, incurs a 5x increase in power demand all else being equal.
  • Data traffic will increase substantially. Even though 5G is highly efficient, throughput rates will be higher and displays will be larger. More bits will be streaming at rates exceeding 1 Gbit per second, requiring additional power.
  • 5G apps will require low latency, about one millisecond. For example, streaming video on a larger screen will sharply reduce idle time for the processor and battery. That means greater power consumption.
  • 5G will require denser placement of antennas across the landscape, and until carriers add more antennas, handsets and their batteries will have to work harder.

In all, network operators estimate 25% to 50% increase in power demand.

Preparedness

There is hope, however, if intelligent battery management software is implemented. The first step is to reduce the stress on the battery; the second is to monitor battery health so that danger is spotted before problems occur. These twin tasks are simple in principle but challenging in practice.

To measure the chemical processes at work, it is possible to utilize the electrical current that charges the battery as a kind of messenger. By applying principles similar to sonar, it is possible to retrieve information from the electrical current’s echo about the chemical reactions within the battery. Based on that information, the reactions can be tuned to make them better performing. These same signals also relay information as to any problems that are developing, such as the dendritic formations that produce electrical shorts.

By lessening battery stress and monitoring battery health, doubling battery longevity is a reasonable expectation. Most phone batteries are rated at 500 charging cycles, but that can be increased to 1000. And battery life isn’t the only thing that can be improved. As a battery charges and recharges, it enlarges in size, gaining perhaps 10 percent in volume. Intelligent battery management can cut that swelling in half.

Simply put, intelligent battery management is a must-have for all smart phones. Nothing else does a better job ensuring battery health and safety. As we await the arrival of 5G, there is no need to despair or to become impatient with the slow progress of battery chemistry technology, when intelligent battery management is here today.

17Jan 2019

Ted Miller, senior manager of energy storage at Ford Motor Co., recently stated:  We don’t see another way to get there without solid-state technology.” The statement is in regard to more powerful batteries for electric vehicles. Mr. Miller goes on clarifying: “What I can’t predict right now is who is going to commercialize it.”

So what is a solid state battery and why is it so difficult to commercialize? 

First, let’s clarify some misconceptions. 

A polymer battery, known as a LiPo, is a lithium-ion battery. 

A cylindrical battery, like an 18650 cell (used in the early Tesla models) is also a lithium-ion battery.

A prismatic battery is too a lithium-ion battery with a hard shell.

And so is a solid-state battery. It involves newer manufacturing processes, but it is a lithium-ion battery. 

All of these variances of lithium-ion batteries have one physical principle in common: the lithium ions contribute to storing the electrical energy.

Simplistically, a lithium-ion battery operates with lithium ions shuffling back and forth between two electrical layers: an anode and a cathode. When the ions are at the cathode, the battery is discharged. When they move to the anode, then the battery is charged. The cathode and anode are called electrodes.

The motion of the ions between these two electrodes is facilitated by an intermediate medium called electrolyte. It is a solution that is electrically conductive: it permits ions to travel through it with little impediment. One key property is called conductivity: it is a scientific measure of the ease at which ions can travel through the electrolyte. High conductivity means the ions can travel easily and quickly. Low means the opposite.

In a lithium-ion battery, the two electrodes are immersed in an electrolyte solution. Today’s batteries use a liquid or gel-like electrolyte. Battery manufacturers go to great lengths to formulate unique electrolytes for their batteries. The formulations do have an impact on many of the battery’s specifications, in particular cycle life (the number of times a battery can be charged and discharged). 

In a solid-state battery, the liquid or gel electrolyte disappears. It is instead replaced by a “solid-state” layer sandwiched between the two electrodes. “Solid-state” means this layer is not a liquid, but a physical solid. The material can consist of a ceramic, glass, or even a plastic-like polymer, or some type of mixture of all three.

So why use a solid electrolyte? There are two major reasons. First, a battery with solid electrolyte occupies a lot less space than one with liquid electrolyte. That means one can pack more energy in the same volume. Consequently, energy density — an important metric of batteries — goes up.

The second reason is safety. Liquid or gel electrolytes are more prone to catching fire than a solid electrolyte.

Traditionally, the primary challenge with solid electrolytes is poor conductivity especially at room temperature (25 °C or 77 °F). A liquid or gel electrolyte has a conductivity that is about 1,000 times better than that of solid electrolyte. In other words, solid electrolytes exhibit a far higher resistance to the flow of lithium ions. This results in several performance challenges, starting with poorer cycle life and inability to charge at fast rates. 

Some companies proposed operating their solid-state batteries at elevated temperatures (> 80 °C) to improve conductivity. But this is not practical under most use scenarios.

Therefore the quest for solid electrolyte materials continues to be a much active field of exploration and discovery. There is confidence in the industry better materials will be discovered, yet, we really can’t predict when a breakthrough will be widely adopted. 

Another challenging aspect is the surface stability and manufacturability of solid electrolytes.  Unlike liquid solutions, glass and ceramic electrolytes are not deformable. They must be assembled with the two electrodes using high external pressure, equivalent to about 1,000 atmospheres. It becomes questionable whether existing battery manufacturing factories can be retooled for this purpose. If not, the economics of solid-state batteries will undoubtedly suffer as is the present case.

In a nutshell, there is much promise in breakthrough material innovations to make solid-state batteries a reality. Yet, many challenges remain ahead. I personally do not expect to see solid-state batteries in commercial scale for several years to come. We will continue to see evolutionary progress with traditional lithium-ion batteries especially as prices continue to decline.

But in all cases, solid-state batteries are subject to the same physical principles that govern traditional lithium-ion batteries. Consequently, many of the battery management solutions developed for traditional lithium-ion batteries will evolve and continue to apply. And that is good news.