How to Make a Battery Performance Claim Your Buyer Will Believe

On February 4, 2026, I was at the inauguration of QuantumScape's Eagle Line when their CTO, Tim Holme, put a Ragone plot on the screen.

He was explaining an 844 Wh/L target at a sub-fifteen-minute 10-to-80 percent charge. And then he did something I rarely see at a launch event. He drew the line between what the cells do today and what the company projects for 1,000 Wh/L, and he labeled which was which.

The room could have taken the bigger number and run with it. He did not let it.

Asim Hussain, QuantumScape's chief business development and marketing officer, described the reasoning plainly. The company shares detailed technical parameters because it does not want to live in what he called "the land of claims."

I have been thinking about that phrase for months, because it names the commercial problem I see more than any other.

How do I explain my battery technology to investors who aren't technical?

Start by being more specific than you think you can afford to be.

There is a tell in battery marketing, and once you see it you cannot stop seeing it. A company that says "industry-leading energy density" or "enhanced safety" usually cannot tell you the test protocol, the cell format, or the cycle count that number held for. A company that gives you Wh/kg at the cell level, capacity retention at a stated cycle count, and the C-rate and temperature it was measured at is telling you something more valuable than the number itself. It is telling you it has data it is willing to be held to.

The second company is almost always further along commercially. Not because its number is better. Because being that specific means engineering, marketing, and leadership have all agreed on what is actually true — and that agreement is the hard part.

Vague claims rarely signal secrecy. In my experience they signal internal disagreement, or performance that is still theoretical, and a buyer who has evaluated more than a few battery companies has learned to read them that way.

The cost is paid by the people doing real work

At CES in January 2026, Donut Lab announced what it called the world's first all-solid-state battery ready for major OEM volumes. The voltage curve in its own materials raised questions about whether the numbers were physically possible. Third-party testing later validated some narrow performance aspects; the headline claims about energy density, scalability, and cycle life were not independently verified.

I am less interested in that company than in what its announcement cost everyone else.

Holme put it this way:

"This attention not being spent on the actual problems. And the actual problems are significant."

Every serious engineer in solid-state spent professional hours that month answering investor questions that required correction, responding to a press cycle built on an unverified claim, and re-explaining why their own timelines were realistic. That is time not spent on the separator chemistry QuantumScape screened two million material combinations to find.

When one company makes a claim it cannot back, the category pays. Buyers become more skeptical of everyone. Diligence gets longer for everyone. The companies with real data end up spending their credibility defending the field instead of advancing their own position.

Why this keeps happening

Battery development runs on years. Funding runs on quarters. That mismatch creates pressure, everywhere in the industry, to describe progress in terms an investor can act on this cycle rather than terms that are scientifically complete.

Most companies do not lie. They frame selectively. They lead with the number that is easiest to compare and leave out the conditions that make it meaningful. Over time that becomes the industry's dialect, and it is a dialect that trains buyers to discount everything they hear.

What to do instead

If you are building a battery company, the discipline is simple to state and hard to hold.

Publish the conditions with the number. Every time. Cell format, test protocol, cycle count, C-rate, temperature. If the number only holds under a specific pressure or cathode loading, say so.

Separate what you have measured from what you project. Label them differently. Holme did this on a slide in front of a room of investors and journalists, and it made the company more credible, not less.

Make sure your engineers and your website agree. If a procurement engineer at a cell maker reads your data sheet and then talks to your CTO and hears a different number, you have lost the deal before the technical review begins — and you will never learn that this is why.

Say what you do not yet know. This one is hardest, because it feels like weakness. It is the opposite. A buyer who hears "we have not yet validated cycle life beyond 500 cycles at this rate" trusts every other number you gave them more.

The advantage is real and it is available

The North American battery industry is not short of smart people or important technology. What it has not yet built is the ability to reliably distinguish signal from noise — and it has built incentive structures that, in some ways, reward noise.

That is a problem for the industry. For an individual company, it is an opening. In a market where most claims are vague, a specific one is unusual enough to be remembered. The company that shows its test conditions, labels its projections, and says out loud what it has not yet proven is not just more honest. It is easier to buy from.

The technology being good is necessary. Being legible about exactly how good, and under what conditions, is what turns good technology into a commercial relationship.

A longer version of this argument, including a fuller account of the Eagle Line inauguration and China's approach to solid-state communication, appeared in Battery Future.