Competitive Alternatives to Lithium-ion Batteries
By SARAH KEELEY
A recent report from S&P Global found that lithium – a lightweight metal used for the making of lithium-ion batteries – will see rising costs over the next decade as demand outstrips supply. High demand for the metal for use in electric vehicle batteries as well as the recent impact of the COVID-19 pandemic on lithium production have put immense pressure on the supply chain with battery producers, mining operations and automotive manufacturers scrambling to secure a steady supply.
Cobalt – another essential mineral that is required in the making of lithium-ion batteries has also seen rising costs with prices doubling since last January to $70,208 per tonne. Cobalt has been subject to controversy as the ethics of the mining of the material have been brought into question. Cobalt is mined primarily in the politically tumultuous Southern region of the Democratic Republic of the Congo.
The COVID-19 pandemic has brought significant transportation disruptions and border closures resulting in soaring prices. The emergence of new variants have also caused new disruptions in the main trade route from Congo through the South African port of Durban to China. All of these factors combined have led many in the booming renewables industry to ask: Do we have viable alternatives to lithium-ion batteries to store the vast amounts of renewable energy that will need to be integrated into the electrical grid to prevent the damaging effects of climate change?
In today’s post, we’ll be looking at some alternative energy storage solutions and their potential applications in the electrical grid of the future.
Flow batteries
Flow batteries have a number of different chemistries such as Vanadium redox, iron and zinc. According to the Energy Storage Association they are most suitable for medium-sized medium-capacity projects. Chemicals are mechanically pumped across electrodes which pushes electricity through the system. At present, their prices are relatively high but these are expected to fall over time. Unlike lithium-ion, power and capacity can be scaled independently so the storage can be tailored more closely to the use case, which results in solutions being more cost-effective. While some of the chemicals used can be environmentally hazardous, much of the system can be recycled when the system is decommissioned.
Flow batteries offer significant benefits in long-duration usage applications and situations that require regular cycling throughout the day. For the renewable generation sector, flow battery technology can extend the availability of renewable solar and wind resources over longer periods of time to counter intermittency issues. Though flow batteries currently have a higher CAPEX than a similar-sized lithium-ion system, they become more competitive when evaluated on a total cost of ownership over a 20- to 30-year lifecycle as flow batteries suffer minimal degradation over time, unlike lithium-ion systems that need to be replaced after 7-10 years.
Thermo-mechanical energy storage
Major progress in the development of thermo-mechanical energy storage systems has been made in recent years, sparking interest in this technology for commercial and industrial applications. Life expectancies in the range of 20–30 years, low costs, a low environmental impact and flexibility regarding sites make thermo-mechanical energy storage a promising option for the storage of electricity.
Cheesecake Energy’s eTanker storage system is one instance of a thermo-mechanical energy storage system. Some TMES technologies such as traditional compressed air energy storage (CAES) require specific geographical features like a salt cavern for storing compressed air; and others, like liquid air require large-scale installations to be viable. eTanker can be installed anywhere, is easily moved from one location to another and has a medium-scale that makes it applicable in a far wider variety of customer use cases such as for EV charging, co-location with solar generators and offgrid applications such as islands and remote mining operations.
Gravitational energy storage
Gravity-based energy storage technology incorporates basic principles of physics that have been used in the production of pumped hydropower plants for years. In pumped hydro systems, water flows down from an upper reservoir to a lower reservoir, passing through and rotating a generator or turbine. Water is then pumped back up from the lower to the upper reservoir, which again rotates the turbine and the system is repeated, generating electricity. In most gravity-based energy storage solutions, a certain mass is lifted upwards using electric motors to charge, and lowered again to release the electricity via generators.
Gravitational energy storage systems tend to be highly-resistant to hard conditions and have no chemical fire risk. Like thermo-mechanical storage systems, the mechanical nature of the systems means they suffer minimal degradation over time. Gravity-based storage technology has applications in renewable energy generation and large commercial and industrial enterprises that generate high amounts of electricity that often exceed demand.
The rapidly evolving green energy industry is driving an increasingly segmented market, putting forward differentiated needs for energy storage. As demand grows and the cost of emerging energy storage technologies fall, it is expected that these alternatives will coexist with and even complement lithium-ion batteries. Energy storage has applications all the way across the electrical system and taken altogether, these technologies have the potential to drive serious electricity decarbonisation and help transform the entire energy sector.
Cheesecake Energy is developing thermal and compressed air energy storage for 30-40% lower cost than lithium-ion batteries, for applications across the electrical ecosystem. To learn more about our technology, click here. If you have a project in mind, get in touch with us today.
Cheesecake Energy Ltd is registered in England and Wales. Company number 10317962.
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