The change has been so gradual you'd hardly notice. Rather than huge multi-cylinder or turbocharged engines, the average wild concept car shown at the Geneva Motor Show is typically powered by fuel cells or batteries, these days.
Making its debut at the show this year is La Vecchia's Quant e-Sportlimousine, whose power system is somewhere in between the two--using a technology known as flow cells.

It features a powertrain developed by nanoFLOWCELL, a German company with technical ties to Bosch.

Breaking it down to simple characteristics, flow cells are like batteries, but share aspects of electrochemical accumulator cells with those of fuel cells.

Liquid electrolytes are stored in two tanks, and circulated through the cells. A membrane separates the two electrolytic solutions, as it does in a fuel cell, and as electrical charge passes from one cell to the other, it produces power for the drivetrain.

All the usual benefits are described here: High charge density, high performance density, light weight. It's also said to contain no harmful substances--ticking a rather important and hotly-debated box--has no moving parts, and is energy-efficient.

MORE: 'Flow Cells' May Let Electric Cars Recharge With Liquid Refills

The upshot is five times greater performance-by-weight than current lithium-ion cells, which in turn means five times greater range than a regular battery of the same weight.

Storage capacity is said to be around 120 kWh, which is a significant chunk more than the 85 kWh Tesla Model S. A claimed 372-mile driving range is the result, and while not explicitly stated the flow cell is sure to be lighter than the Model S battery, which weighs several hundred pounds.

The great unknown is how people may charge the e-Sportlimousine. When we've looked at flow cells previously, their great attraction has been battery-like characteristics with fuel-like filling capabilities. Unfortunately, La Vecchia provides no details here.

The company calls the e-Sportlimousine "neither a show car, nor a concept car". It's clearly both, but to its credit La Vecchia says it intends to build four prototypes for real-world testing.

They're unlikely to feature the e-Sportlimousine's stunning show-car styling with its gull-wing doors, but this is one auto show concept where the technology under the skin is far more interesting than the body clothing it.
At the Geneva Motor Show in March, German firm Quant revealed a car powered by what it called 'nanoFLOWCELL' technology.
Now, the flow-cell vehicle will make its road-going debut, as the car has been approved for real-world testing by the TÜV or Technischer Überwachungsverein, Germany's road safety monitoring agency.

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The first thing most will notice about the Quant e-Sportlimousine is its stunning styling. With a low hood line, double-bubble roof and single-piece gull wing doors it manages to look new and distinctive without resorting to the kind of overt weirdness that might turn people off.

But it's that flow-cell technology that deserves real attention.

Flow cells could be described as a cross between regular batteries and fuel-cells. Liquid electrolyte is circled through two tanks, between which is a membrane. Electrical charge passes through this membrane from one cell to the other, producing power for an electric drivetrain.

It's that simple--but the flow-cell's makers suggest it has high charge density, high performance density and low weight--enough for five times greater performance than a lithium-ion battery of equivalent weight.

MORE: Quant Limousine Concept Pioneers Flow Cell Power Unit At Geneva

The company thus quotes a range of 600 kilometers (372 miles). That's from a flow-cell with 120 kWh of storage capacity--more than a Tesla Model S--but the company's claims imply the flow-cell itself should weigh a lot less than a lithium-ion battery pack.

And like the Tesla, the prototype e-Sportlimousine isn't short of performance.

Torque is quoted as a faintly unbelievable 2,138 pounds-feet "times four", though Quant's performance claims do seem to back up this prodigious output--the 0-62 mph sprint takes 2.8 seconds, and top speed is "over 217 mph".

Ordinarily it would be easy to dismiss these claims as flights of fancy, but since one of Europe's strictest roadworthiness agencies has given the car the green light for public road use, perhaps there's some substance here.

The real benefit is that Quant can test its vehicle in real-world conditions. While cars would be a natural vessel for flow-cell technology, the firm also has its eyes on improving the cost and sustainability of maritime, rail and aviation technology too.
Bovenaan Onderaan