Lithium-ion batteries, the wonders of light power that made possible today’s era of handheld electronics and electric vehicles, have declined in cost since their introduction at a rate similar to the decline in solar panel prices three decades ago, as have that is documented by a study. Published last March. But what is the reason for such an astonishing cost drop of about 97 percent?
Some of the researchers behind that earlier study have now analyzed what is responsible for the extraordinary savings. They found that by far the biggest factor was work on research and development, particularly in chemistry and materials science. This outweighed the gains achieved through economies of scale, although it became the second largest category of deduction.
The new findings are being published today in the journal Energy and Environmental ScienceIn a paper by MIT postdoc Micah Ziegler, recent graduate student Juhyun Song PhD ’19, and professor Jessica Transic at MIT’s Institute for Data, Systems and Society.
According to Transic, the findings could be useful for policy makers and planners to help guide spending priorities for this and other important energy storage technologies to continue the path toward always-low costs. Their work shows that there is still a lot of room for further improvement in electrochemical battery technologies, she says.
The analysis requires digging through a variety of sources, as most of the relevant information consists of closely owned business data. “The data collection effort was extensive,” Ziegler says. “We looked at academic articles, industry and government reports, press releases and specification papers. We also saw some legal filings that came to the fore. We had to piece together data from many different sources to get an idea of what was happening. He says they collected “about 15,000 qualitative and quantitative data points across 1,000 individual records from approximately 280 contexts.”
Data from the earliest times are the most difficult to access and may contain the greatest uncertainties, says Transic, but he attempted to account for these uncertainties by comparing different data sources from the same period.
Overall, she says, “we estimate that most of the cost decline, more than 50 percent, has come from activities related to research and development.” This involved both private sector and government-funded research and development, and within that R&D category the “vast majority” of that cost decline came from chemistry and materials research.
It was an interesting discovery, she says, because “there were so many variables that people were working through a lot of different endeavors,” including the design of battery cells, their manufacturing systems, supply chains, and more. “Cost improvements emerged from the efforts and diverse set of many people, not just the work of a few individuals.”
The findings about the importance of investing in R&D were particularly important, Ziegler says, because much of this investment occurred after the commercialization of lithium-ion battery technology, a stage at which some analysts thought that Research contributions will become less important. Over a nearly 20-year period starting five years after the battery’s introduction in the early 1990s, he says, “most of the cost reduction still came from R&D. R&D contributions ended when commercialization began.” It didn’t happen. In fact, it was still the biggest contributor to cost reduction.”
The study took advantage of an analytical approach that Trancic and his team had initially developed to analyze the similarly sharp decline in the cost of silicon solar panels over the past few decades. He also applied the approach of understanding the rising cost of nuclear power. “It’s really happening at a fundamental mechanism of technological change,” she says. “And we can even develop these models over time, which allows us to uncover levers that people can use to improve the technology in the future.”
She says that one advantage of the methodology that Trancic and her colleagues developed is that it helps reconcile the relative importance of different factors when multiple variables are changing simultaneously, which is usually the case in a technique. as an improvement. “It’s not just adding up the cost effects of these variables,” she says, “because many of these variables affect many different cost components. There’s a complex web of such dependencies.” But the team’s methodology is This makes it possible to see “how the overall cost change can be attributed to those variables, by essentially mapping out that network of dependencies,” she says.
It can help provide guidance on public spending, private investment and other incentives. “What are all the things that different decision makers can do?” she asks. “What decisions do they have so that they can improve the technology, which is important in the case of low-carbon technologies, where we are looking for solutions to climate change and we have limited time and limited resources? It allows us to be a little more intentional about where we invest the time and money.”
“This paper aggregates available data in a systematic way to determine changes in cost components of lithium-ion batteries between 1990–1995 and 2010–2015,” says Laura Diaz Anadon, a professor of climate change policy at the University of Cambridge. , which was not associated with this research. “This period was a pivotal one in the history of the technology, and understanding the evolution of cost components lays the groundwork for future work on the mechanism and may help inform research efforts in other types of batteries.”
The research was supported by the Alfred P. Sloan Foundation, the Environmental Defense Fund and the MIT Technology and Policy Program.