by Binayak Roy, Pavel Cherepanov, Cuong Nguyen, Craig Forsyth, Urbi Pal, Tiago Correia Mendes, Patrick Howlett, Maria Forsyth, Douglas MacFarlane and Mega Kar.
School of chemistry, Monash University,Wellington Road, Clayton, VIC 3800, Australia
Insitutute for Frontier Materials, Deakin University, 221 Burwood Highway, Burwood, VIC
The atmospheric instability and the corrosive tendency of hexafluorophosphate [PF6]− and fluorosulfonylimide [FSI]− based lithium salts, respectively, are among the major impediments towards their application as electrolytes in high voltage lithium batteries. Herein a new class of Li salts is introduced and their electrochemical behavior is explored. The successful synthesis and characterization are reported, including the crystal structure, of lithium 1,1,1,3,3,3-(tetrakis)hexafluoroisopropoxy borate (LiBHfip). The oxidative stability of electrolytes of this salt in an ethylene carbonate:dimethyl carbonate mixture (v/v, 50:50) is found to be 5.0 V versus Li+/Li on various working electrodes, showing substantial improvement over a LiPF6 based electrolyte. Moreover, a high stability of an aluminum substrate is observed at potentials up to 5.8 V versus Li+/Li; in comparison, a LiFSI based electrolyte shows prominent signs of Al corrosion above 4.3 V versus Li+/Li. Cells tested with high voltage layered LiNi0.8Mn0.1Co0.1O2 (NMC811) and spinel LiMn2O4 (LMO) cathodes show stable cycling over 200 cycles with capacity retention of 76% and 90%, respectively. The LMO|Li cell maintains this same low capacity fade rate for 1000 cycles even after the salt has been exposed for 24 h to atmospheric conditions (water content ≈0.57 mass%).
Specialty chemical and polymer manufacturer Boron Molecular is drawing on its chemical synthesis and large-scale production expertise to develop improved electrolytes for new batteries.
Established in 2001, Boron Molecular is a leading specialist chemical manufacturer. The team consists of chemists and chemical engineers with a wide range of expertise across a number of chemical and related industries. Boron Molecular’s core business is the synthesis and production of multi-kilo quantities of specialty chemicals for export to global pharmaceutical industries.
Working alongside Calix and Deakin University, Boron Molecular is actively developing a blueprint for the advanced manufacturing hub of nano-active materials, ionic liquid electrolytes and packing technology.
What’s the involvement of Boron Molecular in the collaboration?
The opportunity for collaboration via the CRC-P (Co-operative Research Centre Project) for Advanced Battery Materials is to develop a technology package that enables us to manufacture batteries here in Australia. Calix will be providing the electrodes, Boron Molecular will be providing the electrolytes and Deakin University will be assembling those components and then testing different configurations for efficiencies.
Institute for Frontier Materials and BAT-TRI Hub, Deakin University
Prof. Patrick Howlett, and Dr Prof. Maria Forsyth, both Research Fellows at Deakin University, lead the Battery Technology Research and Innovation Hub (BatTRI-Hub) within Deakin’s Institute for Frontier Materials (IFM).
BatTRI-Hub is a unique, world class research and innovation centre focused on advanced battery prototyping and the commercialisation of energy storage technologies.
Calix’s battery development programs draw on Deakin’s world-leading expertise in ionic liquid electrolytes, which have an outstanding ability to withstand high temperatures of operation, as well as being non-volatile and less toxic than traditional electrolytes.
“BatTRI-Hub’s cutting-edge prototyping facility will be used in the project to produce pouch cell batteries, optimise their performance and provide batteries for trials with global customers. We are thrilled to be working with Calix and Boron Molecular to utilise the materials manufactured in regional Victoria as the next step towards developing next generation batteries in Australia.”
How does battery research serve our race for a more sustainable world?
“A sustainable energy future requires electricity to be generated and transmitted efficiently from widely distributed and located renewable sources. The transmission of renewable electricity could in part be done via a distribution network, but we also need electricity when the sun is not shining or the wind not blowing. The problem of renewable energy intermittency is solved by energy storage solutions such as batteries.”
We have continued to optimise our lithium manganese oxide (LMO) technology for lithium-ion battery cathodes.
This is a far lower energy route (approximately 6 times less*) than conventional LMO production and is producing “onion-ring” like structures in the tiny crystals.Through our BATMn Technology, we have now optimised a technique for producing manganese oxide and “lithiating” (adding lithium) through a lithium hydroxide solution (a “salt soak”) followed by a significantly shortened heating step.
The materials produced are similar in structure to the best lab-scale, exotic nano-derived materials reported in scientific literature. These structures are well-known for their superior performance. Calix’s materials, produced at a much lower cost, are starting to emulate this performance, being well above the best performing commercial materials.
*(assuming energy requirements are propositional to lithiation time)
Another application for Calix’s core kiln technology – where we are seeing accelerating interest across multiple industries as they try to decarbonise traditional heating processes.
Calix is pleased to announce that it has entered an agreement with Swedish based SaltX Technology Holding AB (“SaltX”) to design and construct a pilot scale 200kW electric powered direct separation reactor (“eDS”) in Sweden to be used as part of a process for storing and dispatching renewable energy.
SaltX has developed a technology that enables efficient peak shifting, to take advantage of the excess renewable energy available during the days and shift its availability to the high demand evening periods. SaltX’s patented “nanocoated” salt is the basis for a chemical looping system that will use Calix’s eDS to “heat” and dehydrate the salt when there is excess renewable energy. The dehydrated salt is then re-combined with water to produce heat and power when needed.
Calix and SaltX have executed a purchase agreement for the design and supply of a 200kW eDS pilot reactor, as part of a demonstration project for the SaltX system. This reactor will be similar to the BATMn reactor that Calix successfully built and commissioned in 2019 at its Bacchus Marsh facility in Victoria.
In addition, Calix will provide a non-exclusive, non-transferable limited license to SaltX to use the eDS reactor for the pilot plant. Calix joins Sumitomo as a partner with SaltX in the development of this system, which has significant potential in helping decarbonise the electricity grid as an energy storage system.
Calix will have the right to undertake its own research in the eDS unit and will work with SaltX on further collaboration on a larger 1MW capacity unit subject to the results achieved at the pilot plant.
Working with SaltX will provide Calix with the opportunity to further develop its eDS designs, apply our technology to a potential chemical energy storage technology and partner with a company with expertise in recovering embodied energy from dehydrated salts.
The rapid growth in electric vehicles and renewable energy storage solutions is creating a global need for more efficient, cheaper, better-performing, and more sustainable energy storage options. While a large part of this growth has been enabled through the performance of lithium-ion (Li-ion) batteries, issues around the cost, capacity, safety, and sustainability of current lithium-ion batteries will increasingly threaten this growth. There is thus a need for advanced materials for lithium-ion batteries that deliver superior performance and safety at lower cost while at the same time reducing environmental impact.
Market opportunity– why are Li-ion batteries of interest?
The Li-ion battery market has grown very quickly, and is predicted to accelerate further…
While there are varying predictions as to the growth for Li-ion battery demand, there is consensus in two things:
How do lithium ion batteries work?
And why is the cathode so important?
During charging, lithium (Li) ions flow from the cathode to the anode via an electrolyte, through a separator. During the discharge, they flow back to the cathode, generating a flow of electrons from the anode into the external circuit (eg. your phone, or car!) and back to the cathode.
The cathode, as the source of Li + ions, is the main determiner of the capacity and voltage of the battery.
The cathode is also the most expensive component of a lithium ion battery.
What are the key operating properties of Li-ion batteries?
Safety, cost and sustainability is what motivated Tesla to move away from cobalt and toward manganese and nickel chemistry.
At the recent “battery day” in September 2020, Tesla announced a move away from cobalt, in favour of manganese and nickel, in the interests of cost, safety and sustainability.
Reference: Tesla Battery Day Validates Manganese For Use In EV Batteries – MarketWatch
The Calix battery R&D team along with its CRC-P for Advanced Hybrid Batteries project partners – Deakin University and Boron Molecular – have been working hard to develop high performance, low-cost and sustainable electrode materials for lithium ion batteries using Calix Flash Calcination compatible processing.
The project is now reaching the 12-month mark and making significant headway having already identified several strong candidate lithium manganese oxide cathode materials. These materials are now being put through their paces at Deakin University’s prototyping facility – BatTRI-hub – in both full coin and pouch cell formats to provide a deeper understanding as to how these materials perform over long-term charge-discharge cycle testing as well as high rate and elevated temperature testing. The Calix team are now focused on further optimisation of its electrode formulations and scale up of the electrode manufacturing process. The CRC-P partners have entered discussions with
global cell manufacturers with the capability to scale up cell production and manufacture battery packs featuring Calix electrode materials for field and customer trials to be run later next year.
The Calix R&D team also welcomes Drs Dabin Wang and Lakshmi Vazhapully who joined Calix from Monash and Deakin Universities in February and May of this year as Battery and Catalyst Materials Engineers. We have also seen the Site Projects Engineer, Terrance Banks, expand his role to take on the additional responsibility of Chief Plant Operator and Engineer for the BatMn pilot plant.
With CRC-P funding, Calix has also been able to refurbish its labs and establish a dedicated space for battery materials R&D at its Bacchus Marsh production facility in Victoria, Australia with expanded capabilities to include X-ray diffraction, rapid surface area analysis and battery testing instruments for high throughput screening and characterisation of its battery materials.
Calix continues to be an active member and supporter of the ARC funded Industrial Innovations Training Centre storEnergy as well as the EU funded POLYSTORAGE training centre supporting projects at Monash, QUT and Deakin Universities on next generation lithium and post lithium ion battery technologies. Calix has also established a placement opportunity at the Bacchus Marsh production facility which provides storEnergy students with valuable industrial experience. Meisam Hasan who is studying for his PhD at Deakin University through the storEnergy training centre under the supervision of Profs Maria Forsyth and Pat Howlett becomes the first student to take up this opportunity.
Calix is also a key participant in the recently established future batteries industries cooperative research centre (FBICRC) and is engaging with the research providers and industry participants to develop a set of integrated projects needed to accelerate the growth of a world leading battery industry sector in Australia.
Calix’s BATMn reactor, completed on time and under budget, was officially opened in November 2019 by Senator David Van. In attendance were local MP Steve McGhie, local Mayor David Edwards, members of AusIndustry and our R&D consortium partners, and of course a very proud Calix team.
Calix develops its technology via a global network of research and development collaborations, including governments, research institutes and universities, some of the world’s largest companies, and a growing customer base and distributor network for its commercialised products and processes.
How will Deakin University be using materials produced by Calix’s BATMn Reactor?
“The materials that come out of the BATMn reactor are really exciting for us. So these are new electrode materials and typically in a battery when you start to play around with the choice of electrode materials or the choice of electrolyte materials, this drastically alters the properties of the battery’s performance. So here we have a new type of material that Calix is producing in the BATMn reactor. The nano structured properties of this electrode material mean that when it is paired with some of our advanced electrolytes that we produce, we hope to achieve some performance in our devices that are superior to the previous generations.” Said Dr Robert Kerr Research Fellow – Electromaterials Deakin University.
How different are the materials produced by BATMn Reactor and how can they help Deakin University?
“Current battery materials have to be very pure so they have to be “sort of the best”, they have to be intricately categorised and from the best value material. What is unique with this reactor is that we can almost get to that same stage, but very quickly, so this technology is able to help us really produce a lot of materials, which is important in production stage and also important in research as well.” Said Dr Timothy Khoo Center Manager ITTC Deakin University.
How does battery research serve our race for a more sustainable world?
“For sustainable energy, one of the key things is the requirement to generate from renewable sources, which are widely distributed and located, and then the need to transmit that energy efficiently. Part of that could be done by a distribution network, but often we also need electricity when the sun is not shining or the wind not blowing, so this intermittent problem is solved by energy storage using batteries.” Said Dr Patrick Howlett Professor – Research Deakin University.
What’s the involvement of Boron Molecular in the collaboration?
“The opportunity for the CRC-P (Co-operative Research Centre Project) is to develop a technology package that enables us to manufacture batteries here in Australia. So Calix will be providing the electrodes, `and Boron Molecular will be providing the electrolytes and Deakin University will be assembling those components and then testing different configurations for efficiencies.” Said Dr Olivier Hutt Director of Business Development Boron Molecular.
What is the next step for Calix?
“The next stage is to really characterise how good the Calix cathode is and how it can optimise the Calix technology and post-processing techniques to really improve the performance of the cathode and also the anode. It’s a very, very exciting project to be involved in, and I think there’s real potential in applying Calix technology for the production of high performance advanced battery catalyst materials.” Said Matt Boot-Handford R&D Manager Batteries and Catalyst Calix Limited.