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Sustainable batteries enter the digital age

Recycling batteries. Photo: Wilfried Pohnke from Pixabay

One part of the drive towards carbon neutrality will be played by sustainable batteries. Lithium-ion technology, while a massive step forward from regular disposable lithium batteries, still produces a range of environmental and humanitarian problems.

The spike in demand that we’ve seen for lithium in the last few years, most probably caused by China announcing a gigantic push to electric car production in 2015, has led to an eye-watering estimate regarding the size of the lithium-ion industry, which is expected to grow from 100 gigawatt hours (GWh) of annual production in 2017, to almost 800 GWhs by 2027. Global battery output is expected to triple by 2025.

As we attempt to address the crisis caused by our reliance on petroleum, we risk provoking a mineral crisis, powered by our current method of battery manufacture. Each tonne of lithium needs 500,000 gallons of water for its extraction, which has been having a devasting effect in various regions: on local farmers in Chile, Bolivia and other parts of South America, who then can’t get the water they need; on rivers in Tibet polluted by toxic chemical leaks, which has happened on at least three occasions in recent years.

Similarly, cobalt is an important raw material currently in use in battery manufacture. Approximately two-thirds of the world’s cobalt comes from the Democratic Republic of the Congo and about one-fifth is estimated to come from sources that can be linked to unsafe working conditions and child labour. Moreover, battery production carries a huge carbon footprint.

It may seem counterfactual to be discussing lithium-ion in this negative manner, given the improvements it brings over lithium and alkaline batteries, the push towards it this century, and indeed the Nobel Prize for Chemistry given to John B Goodenough, M Stanley Whittingham and Akira Yoshino in 2019. However, what the future holds – hopefully – is post-lithium batteries, including redox flow batteries and future battery chemistries that don’t yet exist.

In that regard, Battery 2030+ has followed its 2019 manifesto with a research roadmap earlier this year, which sets out the recommended scientific approach, actions and areas of research required to achieve a carbon-neutral battery. It was developed by a year-long consultation process, has three research themes covering six research areas, and has ambitious and far-reaching aims, as summarised here by the organisation’s director, Professor Kristina Edström of Uppsala University:

“The long-term research directions are based on a chemistry neutral approach that will allow Europe to exceed the ambitious battery performance targets for the full battery value chain, agreed upon in the Strategic Energy Technology Plan (SET Plan) proposed by the European Commission. Thanks to its chemistry-neutral approach, BATTERY 2030+ will have an impact not only on current lithium-based battery chemistries, but also on post-lithium batteries, and still unknown future battery chemistries.”

The three research areas are:

  1. Accelerated discovery of interfaces and materials, comprising Battery Interface Genome (BIG) and Materials Acceleration Platform (MAP)
  2. Integration of smart functionalities, including Sensing and Self-healing
  3. Cross-cutting areas, such as Manufacturability and Recyclability

In terms of the first of the three, a major focus will be on how AI can transform the development of the batteries of the future, which will be smart and connected.

Regarding the second, new concepts in sensors will be able to detect when a battery cell is starting to fail, and that combined with self-healing technology will greatly aid sustainability.

Manufacturing and recyclability will be aided by developing new models and locking them in from the beginning of the process: starting with development, then manufacture, then recycling.

A key ambition of Battery 2030+ is to achieve the lowest possible CO2 footprint. How will this be done? By using sustainably degraded materials, a higher level of material resource efficiency, the smarter functions referred to above, more environmentally friendly manufacturing processes that will reduce cost, and more efficient recycling and remanufacturing methods.

In terms of recycling, life cycle and disposal are a huge issue currently. Lithium is of course a toxic material, and needs to be disposed of properly. While recycling lithium-ion batteries is to be commended, as it reduces energy consumption, greenhouse gas emissions, and results in 51.3% natural resource savings when compared to landfill, it still does not address the environmental issues brought on by manufacture.

Yes, there are fewer greenhouse gas emissions when recyclable batteries are produced and transported, but a longer-term solution is required, hence initiatives like Battery 2030+, which aims to create a circular, carbon-neutral and pollution-free value chain via the use of sodium-ion, multivalent metal-ion, and other post-lithium solutions.

The hope is that the batteries being developed can be produced and recycled cheaply and in as climate-neutral a fashion as possible. The chemistry neutral method being pushed by Battery 2030+ is of major importance here, as the lack of acid or base properties would be a big step forward.

It’s a step we need to take.