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This Molten Salt Battery Will Change The World
At four times the energy density and only a fraction of the cost of lithium-ion
As the world turns its back on planet-wrecking fossil fuels, it starts to revolve more around batteries. EVs, solar power, wind power, tidal power, wave power, and even local energy grids will rely on them to function. But our current battery technology is bulky, expensive, and harmful to the environment, and as such, we desperately need a battery revolution. Luckily, a recent paper detailed a battery that solves pretty much all these issues. But will it be enough?
This battery is a sodium-sulphur molten salt battery. It uses liquid molten salt as its electrolyte and has existed for a long time now (read more about molten salt batteries here). These batteries tend to be cheaper, safer, and more environmentally friendly as they use a smaller amount of widely available materials (in that they don’t require ecosystem-damaging mining practises to source them like lithium-ion does), are non-toxic, and are non-flammable.
Previous molten salt batteries use aluminium-sulphur chemistries, and they tend to have a low energy density and require high temperatures to keep the salt molten, making them relatively useless. But this new one instead uses a unique sodium-sulphur chemistry and a salt that melts at room temperature, making it far more usable, cheap, and eco-friendly than other molten salt batteries. To test this, researchers created a button-cell prototype and put it through its paces, and what they found was remarkable.
Firstly, this battery was incredibly energy dense at 1,017 mAh/g. For some comparison, high energy density lithium-ion batteries are around 250 mAh/g, meaning this battery is four times as energy dense!
Now, there is no data on how much a battery like this would cost. However, estimates for a different molten-salt battery that uses more expensive materials are about $15 per kWh. For comparison, current lithium-ion batteries cost around $132 per kWh. So, assuming this new molten salt battery is of a similar cost, it would be about 90% cheaper than current cells.
Because this new molten salt battery operates at room temperature, it could, in theory, be used in an EV. All you’d…
