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Lithium-ion batteries are the most common battery storage choice for grid operations today, supplying more than 90% of the world’s grid markets. This is because they can store energy efficiently without losing it for long periods of time.
They also feature in consumer electronics, such as smartphones and laptops, and most electric vehicle manufacturers. Lithium-ion batteries even drive research and exploration in space, powering the Mars Curiosity Rover, for example.
The Downside of Cleaner Electric PowerThe development of lithium-ion batteries – and other improvements to battery technology – has helped the planet transition toward using cleaner electric power in the last few decades.
Reliable, long-lasting, and energy-efficient battery technology can enable emissions-free electric infrastructure to become widespread. It can also help us maximize the potential of renewable energy sources by storing and transporting energy from renewable sources worldwide and year-round.
However, lithium extraction to make lithium-ion batteries poses its own environmental challenges. In South America, lithium mining consumes approximately 2.2 million liters of freshwater per ton of lithium produced.
Extracting the toxic material damages soil, and mining operations contaminate the atmosphere by emitting fugitive particles.
Lithium-based batteries are also toxic when discarded. It is possible to recycle these and recover the lithium for future batteries, but lithium recycling is not well established and research in this area seems stagnant.
Alternatives to Lithium in BatteriesIn response to these challenges, researchers worldwide are seeking alternatives. As well as the alternative materials discussed below, alternative production cycles are also recommended. These include better design to ensure longer-lasting batteries and a circular economy model to recover used material.
Aluminum
Aluminum is a readily available resource and one of the most recyclable materials.
It is also much cheaper than aluminum. In 2005, lithium was priced at around $1,460 per ton. This has risen sharply to approximately $13,000 per ton. But in the same period, aluminum’s price (initially more than lithium) only rose from $1,730 to $2,078 per ton.
As a result, many researchers are developing aluminum-based battery technology that could replace lithium. Some of these even perform better than conventional batteries.
Australian company Graphene Manufacturing Group (GMG) claims its aluminum-ion battery charges 60 times faster than conventional lithium-ion batteries.
The GMG battery is made with aluminum atoms inserted inside tiny perforations in graphene planes.
Salt
Salt is very similar to lithium in terms of its chemical make-up. However, its environmental impact is minimal.
Some have proposed sodium-ion batteries as a potential solution to the lithium problem. No viable method has been developed yet, and sodium-ion batteries would be heavier and less powerful than their lithium counterparts due to sodium’s higher density.
Iron
Iron reportedly has higher “redox potential” (or tendency to lose efficiency) than lithium. An Oregon, US-based clean energy company recently invested heavily in the technology.
Currently, iron-flow batteries are much larger than lithium batteries. This makes them unsuitable for phones or electric vehicles, but they could still be good candidates for practical grid storage.
Silicon
Silicon cannot fully replace lithium in batteries, but adding silicon to lithium batteries would make them cheaper and perform for longer.
Lithium-ion batteries currently include graphite as a key component. But lithium slips through gaps in graphite’s stacked carbon layers, resulting in a loss of battery storage over time.
Using silicon instead of graphite would reduce this leakage and create lighter batteries.
Recently, Sila Nanotechnologies brought an innovative battery cell to market. The battery replaces graphite in the anode with silicon and has 20% more energy density than conventional lithium-ion batteries with a smaller battery footprint.
Magnesium
Magnesium can theoretically carry a significant charge of +2, more than either lithium or sodium. Because of this, batteries made out of the material would have a higher energy density, more stability, and lower cost than lithium-ion counterparts used today, according to researchers.
Magnesium atoms could release two electrons each during battery discharge, while lithium atoms only release one. This means that magnesium could potentially transfer twice as much energy as lithium. However, research in this area is still in relatively early stages.
Hemp
A startup in Texas, US, has proposed using hemp to make alternative batteries. The plant is already well regarded for its growth speed, carbon sequestration ability, and versatility as a fiber stock.
Bemp Research has developed a boron carbide battery type made out of hemp. The battery still uses lithium with lithium-sulfur battery technology but is cheaper, lighter, better performing, and easier to recycle than conventional lithium-ion batteries.
