As Europe faced intense heatwaves this summer, a notable increase in demand was observed at Unigrid, a US battery company based in San Diego. The company offers a nine-kilowatt hour battery designed for residential use, which enables homeowners to store electricity at lower rates from the grid and then utilise it during peak cooling times, easing their reliance on air conditioning units.
Growing Interest in Sodium Ion Technology
Darren Tan, the co-founder and CEO of Unigrid, noted interest from countries such as Spain, France, Germany, and the Netherlands, stating that the company has already shipped 100 units and anticipates shipping 1,000 more by year’s end. The interest stems from their sodium ion battery, seen as an alternative to the more common lithium-ion version. Advocates highlight its advantages, such as lower production costs and reduced fire risk, alongside functionality in extreme temperatures down to minus 40 degrees Celsius.
While Unigrid’s batteries currently utilise sodium ion cells produced in China, Tan envisions a future pivot to US-sourced materials, albeit potentially at a higher cost. Despite safety concerns regarding the chromium-3 content in their cathodes potentially converting to toxic chromium-6, Tan reassures that rigorous testing has not yielded such results, with a focus maintained on ensuring battery safety.
Industry Shifts Towards Sodium Ion Solutions
The global shift towards sodium ion batteries is underscored by multiple US-based companies as they explore this promising technology. With Kevin Bell, CEO of Seattle’s Emerald Battery Labs, anticipating sodium ion taking up 80% of the energy storage market, efforts to improve the technology continue. Bell’s firm is currently sourcing sodium ion cells from China while targeting vehicle auxiliary applications.
Meanwhile, California-based Peak Energy, in collaboration with General Motors, aims to establish a domestic manufacturing facility for sodium ion batteries in Michigan by the end of 2028. Their motive is backed by increasing global electricity demands, notably from data centres, and the necessity for sustainable energy solutions.
Future Prospects and Challenges
Despite these ambitious plans, experts acknowledge hurdles such as scaling up to mass production and eliminating fire risks that linger like in traditional lithium-ion counterparts. Ivana Hasa from the University of Warwick remains optimistic, citing the technology’s potential to better manage renewable energy resources and lower energy expenditure.
Ultimately, sodium ion batteries show promise in redefining energy storage solutions, with US companies keen on capturing a significant market share amidst growing environmental and energy challenges.
Reporting based on coverage first published by bbc.co.uk.