ICSF Wave 1: GENESIS: Garnet Electrolytes for New Energy Storage Integrated Solutions

Lead Research Organisation: University of Birmingham
Department Name: School of Chemistry

Abstract

The portable electronics boom has been driven by advances made in Li ion battery technology, following the initial work on the lithium cobalt oxide cathode material by Goodenough and co-workers. Other notable advances in terms of phosphate containing cathodes have extended the applications of lithium ion batteries to higher charge/discharge rate applications such as power tools and transport. Applications in terms of the latter have intensified the already substantial interest in lithium ion batteries, as a result of the environmental benefits of hybrid and all electric cars. Further applications as energy storage for renewable sources have also been proposed to overcome the intermittency of supply problems of renewable energy sources such as solar or wind power. While research on new lithium ion battery electrode materials has been intensive, the development of new electrolyte materials has received comparatively less attention.
In a typical Li ion battery, the electrolyte is usually a Li salt in an organic solvent, as a result of the high Li ion conductivity of such systems. The flammable, toxic and volatile nature of such electrolytes, the instability in conjunction with higher voltage electrode materials, and the desire for miniaturisation are placing distinct limitations on further advances with conventional liquid electrolyte batteries. The use of a solid state electrolyte allows the potential to overcome these problems along with supplying a range of other advances including the simplified production of high voltage battery packs. A further unique advantage of solid state batteries is their low leakage currents, which delivers other potential applications in terms of use in energy harvesting devices. Furthermore the desire for shape-flexible, wearable electronic devices offers another avenue for the exploitation of all solid state battery systems.
This interdisciplinary project involving researchers from chemistry, materials science, chemical engineering and industry aims therefore to develop new Solid State Li ion batteries. Such all solid state cells have been identified as one of the most important future targets in battery research, as illustrated by their inclusion as one of the fast-track projects in the Faraday challenge (industry strategy challenge objective 2). The importance of these batteries lies in their potential to deliver improved safety, reduced size, and higher capacity, as well as to open up new applications such as energy harvesting devices. In particular, the demonstration of a commercially viable scaleable ceramic-based electrolyte with higher safety will offer large benefits in terms of UK wealth generation/investment opportunities (Industry strategy challenge objective 1). In terms of potential commercialisation, the optimisation of garnet Li ion conducting electrolytes, their scale-up synthesis and demonstration in all solid state batteries offers significant potential in terms of Li ion battery technology, with applications ranging from portable consumer devices to transport. In terms of helping to ensure the delivery of impact in this area, a strong link has already been set up with industry, to provide key input into the project from an industrial viewpoint, along with industrial validation of the full cell tests on the most promising systems (industrial strategy challenge objective 3). This will allow UK industry to capitalise on the developments made during this work and offer an early route to exploitation (Industry strategy challenge objective 1).

Planned Impact

Lithium Ion batteries have revolutionised our daily life, with their development leading to the portable electronics boom. More recently they have found use in further applications in terms of hybrid and all electric vehicles. The key benefits of Li ion batteries for such applications are their high power and light weight. However, there are still a number of issues concerning these batteries, with the current electrolyte materials having significant limitations. In particular, these liquid electrolytes tend to be flammable, and unstable in contact with higher voltage electrodes. In addition, the need to contain the liquid electrolyte leads to individual batteries and battery stacks that are larger than ideal. This project is aimed at the development of a suitable solid state electrolyte to overcome such issues, and offer other avenues for further applications, such as energy harvesting devices and shape-flexible, wearable electronic devices. The development and scale up of such solid state electrolytes, and batteries utilising them, will therefore further enhance the applications of Li ion batteries: in particular in terms of transport applications, such advances in battery technology will lead to cleaner transport, thus reducing greenhouse gas emission levels, and so helping the UK to fulfil targets set by the Climate Change Act to cut its emissions by at least 80% from 1990 levels by 2050. The improved safety of such solid state electrolytes will also help ensure that issues regarding flammability, such as the recent Dreamliner battery fires, become a thing of the past. Furthermore, the low leakage rates and potential for miniaturisation of such batteries will open up new avenues for these battery systems as noted above, leading to further significant commercial benefits.

Publications

10 25 50
 
Description We have shown that the Lithium in these Garnet phases can be exchanged by hydrogen ions. This leads to a reduction in lithium ion conductivity. Thus the work shows the need to limit the exposure to moisture during the synthesis of these systems.
We have identified the maximum Li content these Garnet phases can accommodate, and how the Lithium is accommodating in the structure.
We have identified new dopants that can be incorporated into the structure in order to enhance conductivity
We have developed new methodologies for the synthesis of these garnet systems
Exploitation Route The work shows the need to consider the effect of possible reaction of these compounds with moisture
The observation that lithium ordering can be influenced by cation size may help in the design of new materials with improved Li ion conduction
Sectors Energy

 
Description 1. The initial findings have been used to obtain further (APC) funding (£13K) with regard to the scale-up synthesis of garnet electrolytes 2. A link has been set up with a book author, who writes thrillers covering environmental issues. His latest book (currently being written) will relate to Li ion batteries, and Prof. Slater has agreed to be scientific advisor on this book. 3. A range of activities have been run, highlighting the fundamental features of Li ion batteries to schools, including workshops aimed at low ability groups.
First Year Of Impact 2018
Sector Energy
Impact Types Societal,Economic

 
Description APC Feasibility Study
Amount £13,073 (GBP)
Funding ID 56065 
Organisation Advanced Propulsion Centre 
Sector Private
Country Unknown
Start 01/2018 
End 03/2018
 
Description Garnet electrolyte manufacture 
Organisation University of Warwick
Department Warwick Manufacturing Group
Country United Kingdom 
Sector Academic/University 
PI Contribution This is a joint project aiming to develop scaleable routes to the production of garnet electrolytes. We are investigating sol gel based routes
Collaborator Contribution Warwick manufacturing group are investigating solid state approaches
Impact progress has been made in scaling up synthesis, but optimisation is ongoing
Start Year 2018
 
Description Industrial Project partner on grant 
Organisation Qinetiq
Country United Kingdom 
Sector Private 
PI Contribution Sample preparation and characterisation with be done by Birmingham and Imperial College. We will also do initial cell testing to identify the most promising systems
Collaborator Contribution Validation testing of the most promising systems. Attendance and input at project meetings
Impact None as yet at this early stage of the project: validation testing will be performed towards the end of the project
Start Year 2017
 
Description PhD student provision from University of Birmingham (student to start 1/10/18) 
Organisation University of Birmingham
Country United Kingdom 
Sector Academic/University 
PI Contribution The University of Birmingham is funding a PhD student to work on the project. The student will work alongside the PDRAs at Birmingham
Collaborator Contribution The University of Birmingham is funding a PhD student to work on the project to start 1/10/18
Impact PhD student due to start 1/10/18
Start Year 2017
 
Description computer modelling studies on garnet ion conductors 
Organisation Loughborough University
Department Department of Chemistry
Country United Kingdom 
Sector Academic/University 
PI Contribution A collaborative link on combining experimental and modelling studies garnet ionic conductors has been instigated. We are providing the experimental data and interpretation.
Collaborator Contribution Our partners at Loughborough University are doing the computer modelling work
Impact A paper on combined modelling and experimental studies on F doped garnets is currently being worked on
Start Year 2017
 
Description 'Chemistry at Work' at the Black Country Museum 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact Chemistry at work event at the black country museum. Talk and demonstrations on energy technologies including fuel cells
Year(s) Of Engagement Activity 2017
 
Description School workshop 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact schools workshop at Harborne academy
Year(s) Of Engagement Activity 2017
 
Description UK Energy Storage 2018 conference: Structural aspects of Li ion conducting garnets (Poster) 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Poster presentation on the structural characteristics of Li ion conducting garnets: highlighting the effect of Li ordering and Li/H exchange
Year(s) Of Engagement Activity 2018
 
Description workshops on batteries and fuel cells aimed at low ability school children 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Schools
Results and Impact We ran workshops for low-ability Yr 10 students from Balaam Wood School.
This included:
• Introducing Li ion batteries and fuel cells
• Discussing batteries use with small groups e.g. use in everyday life
• Helping students doing a practical on batteries/fuel cells
• Demonstrating a simple fuel cell/battery in action
• Showing students real life fuel cell/battery
Year(s) Of Engagement Activity 2018