General Electric has been working on flow battery technology for years and announced in August 2013 that it aimed to power a car with a water-based battery for 240 miles, though there is no word on whether much progress has been made there. Flow cell batteries have the potential to power cars three times as far and for one-fourth the cost of lithium-ion batteries (the sort that industry darling Tesla Motors is betting big on), according to GE. Flow cell batteries are said to be safer, lighter, and easier to recharge than lithium-ion ones, as well.

It’s a shame, then, that the makers of the Quant e-Sportlimousine had to put their amazing saltwater battery in a car that, should it ever hit the market, may cost about $1.7 million, making Tesla’s Model S luxury electric car look like a bargain at $70,000 to $95,000.

And that’s why Tesla probably has nothing to worry about here: If the only way to get a saltwater-powered battery into a car is to price it like a moderately sized mansion, then lithium-ion batteries just look even better.

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