EU-Fördermittelantrag zur Finanzierung der Überführung eines Verfahrens zur Herstellung verbesserter Lithium-Ionen-Elektroden in die Produktionsreife
Subtask: Description of the Problem
Secondary Lithium Ion Batteries (LIBs) are dominating today’s world market for mobile energy storage devices – and will so in the near and foreseeable future.(1) Power tools, IT devices and – most notably – electric vehicles strongly depend on the small, lightweight high-performance secondary batteries.
However, LIBs do not only hold strengths but also weaknesses that lead to significant performance and safety issues for their users. One of these weaknesses is cell degradation. Over time, the chemical, thermic, and mechanic load of the lithium ions’ movement between anode and cathode, between discharging and charging states – the battery cycle – alters the battery cells. A close examination of LIBs’ aging process found it to be linear in the early stage of cycling, but highly nonlinear later – with a rapid capacity drop and resistance rise. Lithium plating at the anode was identified to be responsible for this significant performance drop(2) and assessed to be the main contributor to the lowering of LIB performance over time.(3)
To minimize the plating of lithium on the anode, the XXXX company XXXX has developed a new technology. It allows battery manufacturers the stable production of improved LIB anodes. These enhanced anodes provide LIBs not only with a longer lifespan and an improved performance. They also can be produced at lower costs – financially as well as ecologically.
Footnotes
(1) W. Zaho: A forum on batteries: from lithium-ion to the next generation. In: National Science Review, Volume 7, Issue 7, July 2020, p. 1263–1268.
(2) S. Zhang: Unveiling Capacity Degradation Mechanism of Li‐ion Battery in Fast‐charging Process. In: ChemElectroChem, Volume 7, Issue 2, January 2020, p. 555-560.
(3) S. Gantenbein, M. Schönleber, M. Weiss, E. Ivers-Tiffée: Capacity Fade in Lithium-Ion Batteries and Cyclic Aging over Various State-of-Charge Ranges. In: Sustainability, Issue 11, 2019, p. 1-15.
Subtask: Describtion of the the state of the art and its limitations
Over the past three decades, there has been much research on possible improvements of LIB anodes.(4) Some researchers tried to find a solution by approaching the problem on the atomic level. They focused on finding compatible new materials, like titanite, to improve the performance of the anode’s slurry foil.(5) Yet, this approach usually implicates unwanted quality changes of the LIBs’ performance(6) and a significant raise in production costs.(7) Therefore, graphite – ‘the’ globally preferred LIB anode material – could keep its dominant position and will continue to do so in the near and foreseeable future.(8)
Other researchers tried to improve the graphite’s quality. Extensively processed natural graphite and the invention of synthetic graphite led to a noticeable performance increase of LIB anodes – but also, again, only for the price of a significant rise of production costs.
A third line of research decided for another approach. It chose to solve the problem on a particle level. Typically, an anode’s graphite particles lay horizontally and muddled on the slurry foil. By aligning the graphite particles vertically, from the anode to the cathode, the path length that lithium ions must cross is reduced. This solution increases the performance of the LIB(9) and – most importantly – slows down the lithium plating and therefore the main factor of the degradation process.(10)
There are two methods for aligning particles: either via microwaves or via magnetic fields.(11) Soon, the latter method became the most developed one. The first patent to use a magnetic field to align graphite particles was registered in 1996 (JP 3443227 B2). Yet, its implementation was not compatible with a cost-effective, continuous manufacturing process – due to the need of high magnetic fields and the disadvantage of low packing density. The same applied to another patent that was registered in 2002 (US 7326497 B2). It tried to solve the low packing density issue by using superconductive magnets. The first patent for a workable solution was registered in 2004 (US 7976984 B2). Yet, to work, the graphite particles had to be rounded mechanically before being aligned under the magnetic field. This rounding process meant an average loss of up to 70 percent of the graphite material. Furthermore, both solutions (US 7326497 B2 and US 7976984 B2) used a homogenous magnetic field, leading to an alignment of the particles parallel to the field. This led to a random arrangement of all non-spheric graphite particles, and that – again – to a return to the low packing density of the particles. In 2013 a new patent was registered (EP 2793300 A1). This technology added magnetic nano particles to the slurry and used a rotating magnetic field. By doing so, the particles not only aligned vertically but also in parallel formation to one another. As a result, they were perfectly ordered. This reduced the diffusion distances lithium ions had to cover to a minimum. Yet, this solution could also lead to unwanted electrochemical processes – with negative consequences for the performance of the produced anodes. Furthermore, all these technologies had two major weak spots. They were not able to apply magnetic fields of the same quality continuously – an absolute necessity in mass production. Moreover, the drying process of the slurry was not effective and could lead to significant performance declines. There was a high risk that the aligned particles lost their orientation during the drying phase – especially when dried with air in the oven via an air blower.
Footnotes
(4) Z. Wang, J. Yu, M. Rao, X. Jin, F. Huld, Z. Xu, Y. Li, F. Lou, D. Ye, Y. Qiu: Challenges, mitigation strategies and perspectives in development of Li metal anode. In: nano select, September 2020, p. 1-17.
(5) J. Billaud, F. Bouville, T. Magrini, C. Villevieille, A. Studart: Magnetically aligned graphite electrodes for high-rate performance Li-ion batteries. In: Nature Energy, Volume 1, Issue 8, August 2016.
(6) J. Duan, X. Tang, H. Dai, Y. Yang, W. Wu, X. Wei, Y. Huang: Building Safe Lithium-Ion Batteries for Electric Vehicles: A Review. In: Electrochemical Energy Reviews, Volume 3, 2020, p. 1–42.
(7) A.-I. Stroe, D.-I. Stroe, V. Knap, S. Maciej, R. Teodorescu: Accelerated Lifetime Testing of High-Power Lithium Titanate Oxide Batteries. In: Proceedings of the 2018 IEEE Energy Conversion Congress and Exposition (ECCE), New York 2018, p. 3857-3863.
(8) J. Asenbauer, T. Eisenmann, M. Kuenzel, A. Kazzazi, Z. Chen, D. Bresser: The success story of graphite as a lithium-ion anode material – fundamentals, remaining challenges, and recent developments including silicon (oxide) composites, In: Sustainable Energy Fuels, Issue 4, 2020, p. 5387–5416.
(9) L. Zhang, M. Zeng, D. Wu, X. Yan: Magnetic Field Regulating the Graphite Electrode for Excellent Lithium-Ion Batteries Performance. In: ACS Sustainable Chemistry & Engineering, Volume 7, Issue 6, February 2019, p. 6152–6160.
(10) J. Billaud, F. Bouville, T. Magrini, C. Villevieille, A. Studart: Magnetically aligned graphite electrodes for high-rate performance Li-ion batteries. In: Nature Energy, Volume 1, Issue 8, August 2016.
(11) L. Wang, J. Han, D. Kong, et al.: Enhanced Roles of Carbon Architectures in High-Performance Lithium-Ion Batteries. In: Nano-Micro Letters, Volume 11, Issue 5, January 2019.
Subtask: Describtion of the innovation
The XXXX XXXX Technology (EP XXXXXXX) is also a production technique for improved LIB anodes. As its predecessors, it also uses electromagnetic fields to align graphite particles vertically on the slurry foil. Yet, unlike them, it allows a qualitatively stable alignment process – from foil to foil to foil – so that a continual, constant production can be ensured. Furthermore, instead of aligning particles along one direction, the technology aligns them along two directions, allowing for a fine-tuning of the alignment’s angle which – as research has shown – enhances the performance of the improved anodes even further. And finally, after the alignment process is completed, particles are immobilized by gelatinizing the slurry foil with a thermo-responsive component.(12) All this ensures that the weak spots of the previous technologies do not come into effect. Therefore, the technology’s most disruptive aspect is that it is the first workable solution to produce improved LIB anodes. It tackles all of the problems of present solutions successfully and does not rise but lower production costs and the ecological footprint of the manufacturing process – as it makes graphite of lower quality suitable for production.(13) The technology’s scenario of use is plain and simple. It can easily be integrated into already existing LIB fabrication processes. The technology has full compatibility with today’s manufacturing materials and processes, is in line with today's electrode production speeds and scalable in accordance with the specific needs of the respective production line.
Footnotes
(12) J. Billaud, F. Bouville, T. Magrini, C. Villevieille, A. Studart: Magnetically aligned graphite electrodes for high-rate performance Li-ion batteries. In: Nature Energy, Volume 1, Issue 8, August 2016.
(13) P. Dolega, M. Buchert, J. Betz: Ökologische und sozio-ökonomische Herausforderungen in Batterielieferketten: Graphit und Lithium. Darmstadt 2020.
Subtask: Describtion of the Impact
The impact on the field of application is that IT devices, power tools, and – most importantly – electric cars will last longer and lose less performance and worth over time. Furthermore, the LIB’s performance and safety – and therefore the usefulness of the mobile devices and vehicles – will be increased. Charging time will be decreased by up to 50 percent, the discharge performance increased by up to 40 percent, and heat generation – due to lower cell resistance – reduced. Finally, LIB market prices – and thereby that of devices and vehicles using LIBs – will drop and attract further consumers. The potential societal value is that the technology will increase society’s interest in buying LIB operated devices and vehicles – thus support the expansion of electric mobility significantly and thereby fuel the global energy transformation.
To the state of the art the technology is an advancement as it allows for a more stable, more cost-effective production of improved LIB anodes.
The broader impact of the technology is that it will significantly reduce the carbon footprint of electric car manufacturing. Over its lifetime, an electric vehicle has a smaller carbon footprint than a gas fuelled car. Yet, for the production phase, the electric car’s footprint is nearly twice as large as that of a gas fuelled car. The reason: the LIB production. It is responsible for more than 40 percent of the car’s carbon footprint. In the next few years, electric car production will increase significantly. Whereas in 2018 only 4 million electric cars were produced, it is estimated that this number will rise to up to 900 million in the next twenty years.(14) This means that a huge part of electrical car manufacturing’s ecological footstep can be saved – simply by using the cheaper improved anode instead of an expensive regular one.
Footnotes
14 I. Tsiropoulos, D. Tarvydas, N. Lebedeva: Li-ion batteries for mobility and stationary storage applications – Scenarios for costs and market growth. Luxembourg 2018.
Subtask: Describtion of the Market Opportunity
XXXX’s technology addresses the global LIB market. Its customers are the global LIB industry and industries building in mobile energy devices, like the IT, the power tool, and the electric car industry. Its users are all final consumers of the beforementioned industries. A strong growth of the LIB market is predicted for the upcoming years. Market research agencies estimate a growth from currently about 40 billion Euro(15) to more than 100 billion Euro by the end of 2030.(16) For 2040, the European Commission even estimates a market size of approximately 200 billion Euro.(17)
The economic benefit provided by the innovation to the key target segment can be quantified as XXXX. The new technology will reduce LIB production costs by XX percent and LIB recycling respectively disposal costs by XX percent which will lead to a price reduction for LIBs of about XX percent.
Footnotes
(15) Markets and Markets (ed.): Lithium-Ion Battery Market by Type (Li-NMC, LFP, LCO, LTO), Power Capacity (0-3,000 mAh, 3,000 mAh-10,000 mAh, 10,000 mAh-60,000 mAh, above 60,000 mAh), Industry (Consumer Electronics, Automotive, Industrial), Voltage, Region – Global Forecast to 2025. April 2020.
(16) Allied Market Research (ed.): Lithium-ion Battery Market by Component (Cathode, Anode, Electrolytic Solution, and Others), End-use Industry [Electrical & Electronics (Smartphones &Tablet/PC, UPS, and Others) and Automotive (Cars, Buses, & Trucks; Scooters & Bikes; and Trains & Aircraft), and Industrial (Cranes & Forklift, Mining Equipment, and Smart Grid & Renewable Energy Storage): Global Opportunity Analysis and Industry Forecast, 2019–2027. April 2020.
(17) I. Tsiropoulos, D. Tarvydas, N. Lebedeva: Li-ion batteries for mobility and stationary storage applications – Scenarios for costs and market growth. Luxembourg 2018.