After 6 independent tests on the same Finnish cell, the energy density figures still disagree by more than a third and the cycle life claim that made the company famous has no test behind it at all

The cell is a foil pouch you could hold in one hand.

It is clamped between two plates, two tabs bent up into a pair of clips, a thermocouple taped flat against one face.

Everything about the setup is ordinary. The argument around it is not.

Compare that with grid storage, where a 780 megawatt project gets built on chemistry nobody finds interesting because it is boring and proven.

One laboratory weighed this design and got a number the industry has been chasing for a decade.

A group of outside experts ran the arithmetic and got a number a third lower.

Both are on the record, and both are about the same cell.

Why two honest labs can weigh the same cell differently

Energy density is watt hours divided by mass, which sounds like it leaves no room to argue.

It leaves plenty. The watt hours depend entirely on how you pull them out.

Discharge a cell slowly, at a tenth of its capacity per hour, and internal resistance barely bites. Almost everything stored comes back out.

Discharge it at a rate a vehicle actually demands and some of that energy leaves as heat instead, so the same cell reports a lower number.

The voltage window matters too. Run the cell across its widest permitted range and you count charge that a production battery management system would never let you touch.

So a headline energy density figure without its rate and its voltage limits attached is not a measurement. It is a setting.

What the tests did establish

Six independent tests exist, run at Finland’s national research center, and several of them came back impressive.

A cell reached 80 percent charge in four and a half minutes at an eleven times capacity rate, which is genuinely fast.

Another survived discharge at 212 degrees Fahrenheit, a temperature that destroys an ordinary lithium ion cell, although the pouch lost its vacuum seal during the run.

A third showed 97.7 percent charge retained after ten days sitting idle.

At pack level, a motorcycle took 100 kilowatts of charging and held it.

None of those tests measured energy density, and none of them measured cycle life.

The two numbers that disagree

In early September the national lab published a figure at last. The cell measured 409.3 watt hours per kilogram and 804.7 per liter.

Read the conditions before you read the number. That was a discharge at a tenth of capacity per hour, at 77 degrees Fahrenheit, across a voltage window from 2.3 to 4.25 volts.

It is a real result under gentle conditions, and it sits above the claim rather than below it.

Against that, an investigation published in June by an independent battery researcher, working with more than 20 experts drawn from a German research institute, two European universities and a Finnish polytechnic, calculated roughly 298 watt hours per kilogram.

That group also disputed the chemistry. It reported voltage behavior at 3.7 to 3.8 volts at half charge, and an expansion signature it read as a graphite anode, both of which point at conventional high nickel lithium ion.

Two credible numbers, one cell, a gap of more than a third, and no reconciliation published by anyone.

The claim nobody has touched

The energy density fight is at least a fight. The durability claim is a vacuum.

A design life of 100,000 cycles would be roughly 270 years of charging once a day, against the one thousand to five thousand cycles good cells manage now.

Six tests in, the cycling data amounts to one run on a cell that was already compromised. Fifty cycles at five times capacity took it from 24.689 amp hours to 11.194, a 55 percent collapse.

That proves nothing about a healthy cell, which is exactly the point. The number that matters most has the least evidence under it.

The company’s chief executive committed to production motorcycles carrying the battery by the end of March. That date passed, and by September there was still no production vehicle running it.

Compare that with grid storage, where a 780 megawatt project gets built on chemistry nobody finds interesting because it is boring and proven.

What is riding on the next report

This is no longer only a technical dispute. The company raised about 25 million dollars from more than 1,300 shareholders through a Finnish crowdfunding platform.

More than 900 of them hold fifty shares or fewer, which describes small retail investors rather than funds that can absorb a loss.

Finnish financial and criminal authorities are reported to be looking at the company, and no finding against it has been made.

What would settle the technical half is unglamorous and cheap. Cycle a healthy cell at a realistic rate, publish the capacity curve, and let it run.

Until somebody does, the story stays where it is, which is a long way from the material supply questions the industry actually has to answer.

The next report either closes the gap or makes it permanent.