High performance batteries play a vital role in powering various devices such as smartphones, laptops, electric vehicles and renewable energy storage systems. With the growing demand for these devices there is an increasing need to advance battery technology in order to achieve energy density, longer battery life and faster charging capabilities.
One area of research that shows promise is the development of silicon based anodes. Silicon has the potential to significantly increase the energy density of batteries compared to graphite anodes. Researchers are focusing on exploring silicon based anodes due to their higher theoretical capacity when compared to graphite. In fact silicons have a specific capacity of up to[R1] 3578 mAh/g – nearly ten times greater than graphite. To achieve this improvement scientists are experimenting with a material consisting of micrometric[R2] Si, graphite (MAG) LiI−Li3PS4 solid electrolyte (LPSI) and carbon nanofiber (CNF). This composite material integrated with 5 wt% CNF demonstrates a capacity, above 1200 mAh/g throughout 50 cycles in a bulk type all solid state battery using LPSI as the electrolyte.
Silicon-Based Anodes: A Promising Solution to Current Battery Technology
There are limitations to current battery technologies due to their low theoretical capacity (372 mAh[R3] g−1) while their low energy density (150 Wh kg), which represents how much energy can be stored per unit volume or weight. An increase in energy density is essential for extending the battery life of portable devices and improving the range and performance of electric vehicles. Silicon anodes have a higher energy density and higher theoretical capacity of Si (42,200mAh g, 10 times that of silicon anodes) compared to graphite anodes. As a result, silicon-based anodes can store more energy, making batteries last longer and perform better.
The charging time of batteries can sometimes be a drawback in situations where quick charging is necessary. Improving the speed at which batteries charge is crucial for providing users with an experience and facilitating the development of rapid charging infrastructure. Silicon based anodes have the potential to facilitate charging as well as the excellent conductivity of silicon allows for diffusion of lithium ions resulting in shorter charging times and improved overall battery performance. It has been observed that Silicon based anodes have an energy capacity 11[R4] times higher, than graphite based anodes.
Batteries degrade over time, leading to a decrease in capacity and overall performance. Short lifespan is a significant challenge in battery technology, as it affects the usability and reliability of energy storage systems. Battery lifespan is 20[R5] % longer for silicon-based anodes compared to graphite-based anodes. This is because silicon is able to accommodate more lithium ions during charging and discharging cycles, leading to improved battery durability and longevity.
Applications and Market Potential
The silicon-based anodes market is experiencing significant growth due to the increasing demand for high-capacity lithium-ion batteries. Li-ion batteries’ global demand is expected to skyrocket over the next decade, with about 700 GWh demanded in 2022 and around 4[R6] .9 TWh by 2030. According to Research Nester estimates, the Silicon-based anode market size is expected to reach USD 137 billion by 2036, growing at around 48% CAGR during the forecast period. Silicon-based anodes had an industry size of USD 3 billion in 2023. As a result of a regulatory shift toward sustainability, which includes new net-zero targets and guidelines, mobility applications, such as electric vehicles, are growing in popularity. Some of the initiatives include Europe’s “Fit for 55” program, the US Inflation Reduction Act, the ban on internal combustion engine (ICE) vehicles in the EU by 2035[R7] , and India’s Faster Adoption and Manufacturing of Hybrid and Electric Vehicles.
A number of major players dominate the Silicon based Anode market including Tesla, LG Chem, Samsung SDI Co., Ltd., SK Innovation Co., Ltd., Northvolt AB Sila Nanotechnologies Inc., Amprius Technologies, Enevate Corporation, 24M, Enovix Corporation.
Silicon-based anodes have shown great promise in battery technology, offering numerous benefits and a wide range of applications. The market potential for this innovative technology is also significant, with various industries looking to harness its capabilities.
Electric Vehicles
The global electric vehicle market is experiencing rapid growth, with increasing demand for high-performance batteries. Over $245[R8] billion is the market value of the EV industry. There has been a 15x increase in worldwide sales of battery-electric vehicles since 2017. Globally, 7.4 million battery-electric vehicles will be sold in 2022. Silicon-based anodes have the potential to capture a significant market share. Silicon-based anodes can significantly increase the energy density and overall performance of electric vehicle batteries, leading to longer driving ranges and shorter charging times.
Consumer Electronics
The consumer electronics industry is constantly evolving, with a growing demand for longer-lasting batteries. A 32[R9] gigawatt-hour battery requirement is predicted for India’s consumer electronics sector by 2030. Smartphones, laptops, and other portable devices can benefit from silicon-based anodes, which offer higher capacity and longer battery life.
Renewable Energy Storage
As renewable energy sources become more prevalent, the need for efficient and reliable energy storage solutions is increasing. Global renewable energy supply from solar, wind, hydro, geothermal, and ocean sources increased by close to 8% in 2022[R10] . In 2022, solar PV generated 270[R11] TWh, an increase of 26% over 2021. Silicon-based anodes can play a crucial role in meeting this demand. Silicon-based anodes can enhance the storage capacity and efficiency of batteries used in renewable energy systems, such as solar and wind power.
Medical Devices
The medical device industry is constantly seeking advancements in battery technology to improve the performance and lifespan of implantable devices. It is critical that medical batteries can withstand between 450 and 950 cycles under 100[R12] % DoD cycling conditions while maintaining 82% of the initial capacity retained. Silicon-based anodes can address this need. Implantable medical devices, such as pacemakers and insulin pumps, can benefit from the higher energy density and longer lifespan provided by silicon-based anodes.
Grid Energy Storage
With the transition to renewable energy sources, grid energy storage systems are becoming essential for maintaining a stable electricity supply. In the year 2022[R13] , there were approximately 28 GW of grid-scale battery storage installed. As compared with 2021, there was a 75% increase in installations in 2022, with around 11 GW of additional storage capacity added. Silicon-based anodes can contribute to the growth of this market. Large-scale energy storage systems, used to stabilize and balance electricity grids, can be more efficient and cost-effective with the use of silicon-based anodes.
Recent Developments[R14] in Silicon Based Anodes
Recent Research Findings
Nanostructured silicon has been investigated as a potential solution to address volume expansion and poor cycling stability. By reducing the size of silicon particles, nanostructured silicon can accommodate the volume changes during lithiation and delithiation processes more effectively. Si nanoparticles of sizes 5, 10, and 20 nm have been synthesized under high pressure at 380[R15] °C using a variety of surfactants.
Silicon-carbon composites have emerged as a promising approach to improve the performance of silicon-based anodes. The combination of silicon and carbon can mitigate the volume expansion issue and enhance cycling stability. For instance, with a yolk-shell structure, Si@Carbon has excellent capacity (2, 833[R16] mAhg-1 at C/10), cycle life (1,000 cycles with 74% capacity retention), and cubic efficiency (99.84%). Silicon oxide has shown potential in addressing the challenges of silicon anodes. By incorporating silicon oxide into the anode structure, it is possible to improve the cycling stability and capacity retention.
Improved Electrode Designs
Core-shell structures are one of the innovative designs that have been developed to address the volume expansion issue of silicon anodes. These structures consist of a silicon core surrounded by a shell material that can accommodate the expansion and contraction of the silicon during cycling. An 86% capacity retention hollow core shell porous Si–C nanocomposite having 650[R17] mA h g-1 capacity after 100 cycles (current density 1 A g-1).
Another approach to mitigate the volume expansion issue is the use of porous silicon[R18] structures. These structures have a high surface area, which allows for better accommodation of the volume changes during cycling. Additionally, the porosity of the silicon can also improve the lithium ion diffusion kinetics.
Silicon nanowires are another promising design for silicon-based anodes. These nanowires have a high aspect ratio, which allows for better strain accommodation. The one-dimensional structure of the nanowires also facilitates the transport of lithium ions, improving the overall performance of the anode.
Efforts in Commercialization
Companies are investing in research and development to scale up the production of silicon-based anodes. This involves increasing the capacity of manufacturing facilities and optimizing production processes to meet the growing demand for lithium-ion batteries. For instance, In May 2023[R19] , As part of its plans to build Europe’s largest anode factory in Sundsvall, central Sweden, Putailai, one of the world’s largest anode producers in China, will invest $1.5 billion (SEK 15.7 billion) in Zichen Technology (Sweden) AB.
Collaboration between manufacturers, industry, and government organizations is crucial to accelerate the development and commercialization of silicon-based anodes. For instance, in December 2023[R20] , an agreement was signed between Panasonic Energy Co., Ltd., a Panasonic Group company, and Sila Nanotechnologies, a battery materials company, to develop silicon anode batteries for electric vehicles.
Current Limitations of Silicon-Based Anodes and Overcoming Them
Capacity Loss: Silicon-based anodes have a high theoretical capacity, but they suffer from a significant volume expansion during lithiation, which leads to capacity loss. The expansion and contraction of silicon during charge and discharge cycles cause mechanical stress and pulverization of the anode material.
Solution: One approach to address capacity loss is to use nanostructured silicon materials. These materials have a high surface-to-volume ratio, which helps accommodate the volume changes and reduce the formation of cracks. Also, using silicon-containing alloys, such as silicon-tin or silicon-germanium, can also help address capacity loss. These alloys have a higher structural stability compared to pure silicon, reducing the volume changes and improving the cycling stability. They can effectively accommodate the lithiation and delithiation processes, leading to better overall performance.
Cycling Stability: Silicon-based anodes experience a decrease in cycling stability due to the formation of a solid-electrolyte interface (SEI) layer on the surface of the anode. The SEI layer hinders the diffusion of lithium ions and increases the resistance of the electrode, resulting in capacity fade over multiple charge and discharge cycles.
Solution: Applying protective coatings to the silicon-based anodes can help prevent degradation and improve cycling stability. Coatings such as carbon, graphene, or polymer films can provide a barrier between the silicon and the electrolyte, reducing the formation of solid-electrolyte interphase (SEI) and minimizing capacity decay.
Volume Expansion: Another challenge in the development of silicon-based anodes is the issue of volume expansion. Silicon has a high theoretical capacity for lithium-ion storage, but it undergoes a significant expansion during lithiation, which can cause mechanical stress and lead to electrode failure.
Solution: Nanostructuring the silicon anode helps accommodate the volume expansion during lithiation and delithiation cycles. The reduced diffusion path length and increased surface area enhance the electrode’s stability and capacity retention. Incorporating silicon into a composite electrode with other materials, such as carbon, can mitigate volume expansion.
Future Directions
Silicon-based anodes offer a sustainable and efficient solution for battery technology. With their high capacity and excellent cycling stability, they have the potential to revolutionize the energy storage industry. The wide range of applications, from consumer electronics to electric vehicles, makes silicon-based anodes a versatile choice for various industries. Furthermore, the growing demand for renewable energy sources and the increasing focus on sustainable development provide a favorable market for silicon-based anodes. As research and development continue to improve their performance and reduce costs, silicon-based anodes are poised to play a significant role in the future of battery technology.
Source: https://www.researchnester.com/reports/silicon-based-anode-market/5324
[R1]https://www.financialexpress.com/business/express-mobility-rise-of-silicon-graphite-the-key-to-longer-range-and-faster-charging-evs-3237954/
[R2]https://chemistry-europe.onlinelibrary.wiley.com/doi/abs/10.1002/cssc.202202235
[R3]https://www.mdpi.com/1420-3049/28/5/2079
[R4]https://www.mdpi.com/2304-6740/11/5/182
[R5]https://nanografi.com/blog/advantages-of-silicon-anode-materials-for-lithiumion-batteries-/#:~:text=Silicon%20makes%20the%20batteries%20last,remarkable%20characteristics%20as%20LIB%20anodes.
[R6]https://www.mckinsey.com/industries/automotive-and-assembly/our-insights/battery-2030-resilient-sustainable-and-circular#:~:text=Global%20demand%20for%20Li%2Dion,by%202030%20(Exhibit%201).
[R7]https://www.mckinsey.com/industries/automotive-and-assembly/our-insights/battery-2030-resilient-sustainable-and-circular
[R8]https://explodingtopics.com/blog/ev-stats
[R9]https://www.statista.com/statistics/1415497/india-consumer-electronics-battery-demand/#:~:text=Consumer%20electronics%20battery%20demand%20in%20India%202022%2D2030&text=In%202030%2C%20it%20was%20estimated,increase%20in%20comparison%20with%202022.
[R10]https://www.iea.org/energy-system/renewables
[R11]https://www.iea.org/energy-system/renewables/solar-pv
[R12]https://www.embedded.com/assessing-lithium-ion-battery-life-for-implantable-medical-devices/
[R13]https://www.iea.org/energy-system/electricity/grid-scale-storage
[R14]https://www.sigmaaldrich.com/IN/en/technical-documents/technical-article/materials-science-and-engineering/batteries-supercapacitors-and-fuel-cells/recent-developments-in-silicon-anode-materials
[R15]https://www.sigmaaldrich.com/IN/en/technical-documents/technical-article/materials-science-and-engineering/batteries-supercapacitors-and-fuel-cells/recent-developments-in-silicon-anode-materials
[R16]https://www.sigmaaldrich.com/IN/en/technical-documents/technical-article/materials-science-and-engineering/batteries-supercapacitors-and-fuel-cells/recent-developments-in-silicon-anode-materials
[R17]https://www.sigmaaldrich.com/IN/en/technical-documents/technical-article/materials-science-and-engineering/batteries-supercapacitors-and-fuel-cells/recent-developments-in-silicon-anode-materials
[R18]https://pubs.acs.org/doi/abs/10.1021/acs.iecr.3c00084
[R19]https://www.fastmarkets.com/insights/chinas-putailai-to-build-anode-factory-in-sweden/
[R20]https://na.panasonic.com/us/news/panasonic-energy-partners-sila-procurement-next-generation-silicon-anode-material-ev-batteries
