There is widespread agreement among scientists that the use of fossil fuels in electricity generation is a leading cause of climate change. Despite some progress in incorporating wind and solar power, fully transitioning away from fossil fuels remains a challenge.
One of the barriers to adopting renewable power is the intermittent supply of energy from renewable sources. To overcome this, we need efficient and affordable energy storage systems to fulfill grid demands when solar or wind power is unavailable.
Most batteries today are made of lithium. However, we must discover an inexpensive and safe alternative to lithium to transition toward a completely renewable power sector.
Although lithium-ion batteries have been widely used for grid-scale energy storage due to their high energy density and modularity, they come with their own drawbacks. These include high material costs, risks of fire and explosion, and inadequate recycling practices.
Lithium-ion batteries have also been linked to human rights abuses in developing nations.
In contrast, new zinc-ion batteries (pictured above) have emerged as a promising alternative. They offer advantages such as lower material costs, improved safety, and easier recycling.
The commercialization of zinc-ion batteries could be pivotal in integrating renewables into energy infrastructure. This would enable various nations to achieve their decarbonization targets.
Research has indicated that in order for renewable energy to account for 90 to 95 percent of electricity generation, the cost of energy storage should be below US $150/kWh. According to Inverse, modern lithium-ion systems are still priced at around US $350/kWh.
Zinc-ion batteries offer a potential solution to address cost and availability concerns. By utilizing inexpensive and abundant materials, such as zinc and manganese, these batteries become more affordable to produce.
This raw material abundance also makes zinc-ion batteries less vulnerable to supply chain disruptions than their lithium-ion counterparts.
A 2021 study found that zinc-ion batteries are up to 50% cheaper than lithium-ion batteries. This is largely due to the fact that zinc is over 100 times more abundant than lithium.
Zinc-ion batteries also offer advantages with regard to safety. They replace the flammable and toxic solvent-based electrolyte of lithium-ion batteries with a water-based alternative. This eliminates the risk of fires and explosions.
Conversely, the proper disposal of lithium-ion batteries can pose challenges due to their toxic compounds. This makes recycling economically unfeasible and results in a significant number of spent cells ending up in landfills.
Fortunately, the end-of-life treatment of zinc-ion batteries is simplified. The non-toxic, aqueous electrolyte used in these batteries allows for established methods, like those used for lead-acid battery disposal, to be applied. Additionally, the metallic zinc anode can be easily reused in new batteries.
Although zinc-ion batteries are a relatively recent innovation, their capacity to facilitate large-scale energy storage on global grids should not be underestimated.
Image Source: Battery Technology, https://shorturl.at/bEV19