Solar Energy News
ENERGY TECH
Researchers discover a surprising way to jump-start battery performance
Giving lithium-ion batteries their first charge at high currents before they leave the factory is 30 times faster and increases their lifespans by 50%.
Researchers discover a surprising way to jump-start battery performance
by Glennda Chui for SLAC News
Stanford CA (SPX) Sep 01, 2024

A lithium-ion battery's very first charge is more momentous than it sounds. It determines how well and how long the battery will work from then on - in particular, how many cycles of charging and discharging it can handle before deteriorating.

In a study published in Joule, researchers at the SLAC-Stanford Battery Center report that giving batteries this first charge at unusually high currents increased their average lifespan by 50% while decreasing the initial charging time from 10 hours to just 20 minutes.

Just as important, the researchers were able to use scientific machine learning to pinpoint specific changes in the battery electrodes that account for this increase in lifespan and performance - invaluable insights for battery manufacturers looking to streamline their processes and improve their products.

The study was carried out by a SLAC/Stanford team led by Professor Will Chueh in collaboration with researchers from the Toyota Research Institute (TRI), the Massachusetts Institute of Technology and the University of Washington. It is part of SLAC's sustainability research and a broader effort to reimagine our energy future leveraging the lab's unique tools and expertise and partnerships with industry.

"This is an excellent example of how SLAC is doing manufacturing science to make critical technologies for the energy transition more affordable," Chueh said. "We're solving a real challenge that industry is facing; critically, we partner with industry from the get-go."

This was the latest in a series of studies funded by TRI under a cooperative research agreement with the Department of Energy's SLAC National Accelerator Laboratory.

The results have practical implications for manufacturing not just lithium-ion batteries for electric vehicles and the electric grid, but for other technologies, too, said Steven Torrisi, a senior research scientist at TRI who collaborated on the research.

"This study is very exciting for us," he said. "Battery manufacturing is extremely capital, energy and time intensive. It takes a long time to spin up manufacturing of a new battery, and it's really difficult to optimize the manufacturing process because there are so many factors involved."

Torrisi said the results of this research "demonstrate a generalizable approach for understanding and optimizing this crucial step in battery manufacturing. Further, we may be able to transfer what we have learned to new processes, facilities, equipment and battery chemistries in the future."

A "squishy layer" that's key to battery performance
To understand what happens during the battery's initial cycling, Chueh's team builds pouch cells in which the positive and negative electrodes are surrounded by an electrolyte solution where lithium ions move freely.

When a battery charges, lithium ions flow into the negative electrode for storage. When a battery discharges, they flow back out and travel to the positive electrode; this triggers a flow of electrons for powering devices, from electric cars to the electricity grid.

The positive electrode of a newly minted battery is 100% full of lithium, said Xiao Cui, the lead researcher for the battery informatics team in Chueh's lab. Every time the battery goes through a charge-discharge cycle, some of the lithium is deactivated. Minimizing those losses prolongs the battery's working lifetime.

Oddly enough, one way to minimize the overall lithium loss is to deliberately lose a large percentage of the initial supply of lithium during the battery's first charge, Cui said. It's like making a small investment that yields good returns down the road.

This first-cycle lithium loss is not in vain. The lost lithium becomes part of a squishy layer called the solid electrolyte interphase, or SEI, that forms on the surface of the negative electrode during the first charge. In return, the SEI protects the negative electrode from side reactions that would accelerate the lithium loss and degrade the battery faster over time. Getting the SEI just right is so important that the first charge is known as the formation charge.

"Formation is the final step in the manufacturing process," Cui said, "so if it fails, all the value and effort invested in the battery up to that point are wasted."

High charging current boosts battery performance
Manufacturers generally give new batteries their first charge with low currents, on the theory that this will create the most robust SEI layer. But there's a downside: Charging at low currents is time-consuming and costly and doesn't necessarily yield optimal results. So, when recent studies suggested that faster charging with higher currents does not degrade battery performance, it was exciting news.

But researchers wanted to dig deeper. The charging current is just one of dozens of factors that go into the formation of SEI during the first charge. Testing all possible combinations of them in the lab to see which one worked best is an overwhelming task.

To whittle the problem down to manageable size, the research team used scientific machine learning to identify which factors are most important in achieving good results. To their surprise, just two of them - the temperature and current at which the battery is charged - stood out from all the rest.

Experiments confirmed that charging at high currents has a huge impact, increasing the lifespan of the average test battery by 50%. It also deactivated a much higher percentage of lithium up front - about 30%, compared to 9% with previous methods - but that turned out to have a positive effect.

Removing more lithium ions up front is a bit like scooping water out of a full bucket before carrying it, Cui said. The extra headspace in the bucket decreases the amount of water splashing out along the way. In similar fashion, deactivating more lithium ions during SEI formation frees up headspace in the positive electrode and allows the electrode to cycle in a more efficient way, improving subsequent performance.

"Brute force optimization by trial-and-error is routine in manufacturing - how should we perform the first charge, and what is the winning combination of factors?" Chueh said. "Here, we didn't just want to identify the best recipe for making a good battery; we wanted to understand how and why it works. This understanding is crucial for finding the best balance between battery performance and manufacturing efficiency."

This research was funded by the Toyota Research Institute through its Accelerated Materials Design and Discovery program.

Research Report:Data-driven analysis of battery formation reveals the role of electrode utilization in extending cycle life

Related Links
SLAC National Accelerator Laboratory
Powering The World in the 21st Century at Energy-Daily.com

Subscribe Free To Our Daily Newsletters
Tweet

RELATED CONTENT
The following news reports may link to other Space Media Network websites.
ENERGY TECH
Study of disordered rock salts leads to battery breakthrough
Boston MA (SPX) Aug 23, 2024
For the past decade, disordered rock salt has been studied as a potential breakthrough cathode material for use in lithium-ion batteries and a key to creating low-cost, high-energy storage for everything from cell phones to electric vehicles to renewable energy storage. A new MIT study is making sure the material fulfills that promise. Led by Ju Li, the Tokyo Electric Power Company Professor in Nuclear Engineering and professor of materials science and engineering, a team of researchers desc ... read more

ENERGY TECH
CABBI team designs efficient bioenergy crops that need less water to grow

Engineered microbes efficiently convert CO2 into key pharmaceutical precursors

UK power firm to pay fine over inaccurate data on wood

Turning bacteria into bioplastic factories

ENERGY TECH
AI chatbots must learn to say 'help!' says Microsoft exec

Axiom Space and AWS advance AI Assistant for space missions

OpenAI, Meta flex muscles as AI race heats up

Macron says Europe needs own AI model to 'catch up'

ENERGY TECH
Researchers develop method for chemically recyclable wind turbine blades

India's green energy wind drive hits desert herders hard

MIT engineers' new theory could improve the design and operation of wind farms

Engineers Develop Cost-Effective Seafloor Testing Device for Offshore Wind Farms

ENERGY TECH
Norway's electric car sales set new world record

BMW eyes hydrogen-powered rollout in 2028, with Toyota help

Ex-VW boss tells trial 'dieselgate' charges are 'implausible'

Toyota shutters Japan factories as typhoon approaches

ENERGY TECH
Argonne to lead National Energy Storage Research Hub

Researchers discover a surprising way to jump-start battery performance

Bubbling, frothing and sloshing: Long-hypothesized plasma instabilities finally observed

Innovative smart windows cool buildings and generate electricity without external power

ENERGY TECH
Assorted, distinctive behavior of molten uranium salt revealed by neutrons

UN nuclear head says discussed Kursk plant safety with Zelensky

New French nuclear reactor enters automatic shutdown

Framatome Gains U.S. Approval to Transport Higher Enriched Nuclear Fuel

ENERGY TECH
UK announces record green energy auction

Treasury Department, IRS, propose expansion of clean energy tax credits

China nears peak emissions as climate envoy meets US counterpart

Court rules S. Korea climate goals 'unconstitutional'

ENERGY TECH
Chinese GF-7 satellite enhances forest height measurement accuracy

ForINT: A new platform for comprehensive forest intelligence

Carbon emissions from forest soils expected to rise with global warming

Experts puzzled as Finland pine trees die off

Subscribe Free To Our Daily Newsletters




The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.