It's hard enough convincing investors to trust advanced battery technology when it's the increasingly recognizable lithium-ion variety. New Jersey-based battery startup Eos has a different challenge: pitching a technology few have heard of,* because the company was the first to invent it.

Its major tool in overcoming that challenge is price. Eos team members say they are already selling their system at $160 per kilowatt-hour for high-volume orders. That's the DC system cost, so it doesn't include inverters or installation, but it trounces the advanced battery competition and has raised many an eyebrow in the industry.

A mind-blowing price captures customers' attention, but doesn't necessarily secure their trust. Eos has created a new energy storage technology the company calls zinc hybrid cathode. To build confidence in the product, the company has turned to established, recognizable companies to get the product to customers. Eos announced two of these in the week leading up to the DistribuTech Conference in San Diego.

The 165-year-old technology powerhouse Siemens will work with Eos to deploy the batteries, adding power conversion for the DC systems as well as project development expertise. Those Eos installations will benefit from the gravitas of the Siemens name, although the warranty is still Eos' responsibility. Siemens is not yet putting its balance sheet behind the guaranteed performance warranty for the AC system.**

Eos has also forged a power conversion and project development partnership with Northern Power Systems, an energy company specializing in wind power that has more than four decades of experience under its belt.

These two companies are now members of the Aegis program, Eos' network of integrators. By leveraging the expertise and name recognition at the Aegis partners, Eos can punch above the weight of a small battery startup.

"Even the most excited customer cannot necessarily do something with a DC battery -- they need a turnkey offering that integrates batteries with AC balance of plant, EPC and O&M services to guarantee its performance under certain use cases and for specified durations," said Philippe Bouchard, Eos vice president of business development.

One battery, many partners

While attempting to crack the difficult zinc-air technology for long-duration, long-cycle-life applications, Eos hit upon the zinc hybrid cathode design. The details are still proprietary, but it involves stacking cells made with a minimalist six ingredients, including titanium, salt water and carbon. The company claims, based on accelerated cycle life testing, that the systems can last up to 20 years, depending on use.

Now the technology is coming to market as the Eos Aurora, packing 1 megawatt and 4 megawatt-hours into an outdoor-rated enclosure. It's modular and scalable to bigger sizes. The initial market is utilities and utility-scale project developers, but Eos can also break out the building blocks of the Aurora to offer 250-kilowatt, 1-megawatt-hour solutions for behind the meter.

What Eos doesn't have is a bespoke inverter or an in-house distribution network -- hence the need for partnering. It takes time to do the work of integrating the Aurora with each partner's power electronics, and no doubt involves a certain degree of reinventing the wheel. Pursuing several partnerships, though, gives Eos access to more distribution channels and geographic markets and avoids the risks of gambling its success on the performance of any one other company.

Eos and Siemens first began the conversation five years ago, Bouchard said, and the two have been working on integration and system design for a year and a half. Siemens was "extremely rigorous and comprehensive in their due diligence," he noted.

The partnership lets Eos focus on what it does best, said CEO Michael Oster.

"We have an Eos-Siemens system and our customers will be very confident in that," he said. "Siemens has a low-cost offering where they can beat the competition on cost."

As part of that relationship, Siemens is installing the first of the latest Eos technology at its headquarters in Alpharetta, Georgia to gain field experience before deploying it for customers.

In the first half of 2017, Eos will focus on demonstration projects with major utilities, the execs said, but by summer it will deliver multi-megawatt installations developed and financed by third parties. They added that ramping up production for large utility-scale systems, like a 10-megawatt, 40-megawatt-hour system awarded by Pacific Gas & Electric, will help them ride the cost curve down.

That points to the defining mystery swirling around this company: how on earth it can actually sell at that price point.

How low can they go?

For reference, current lithium-ion systems sell for an average of $350 per kilowatt-hour. By 2020, GTM Research expects average lithium-ion battery costs to hit $217 per kilowatt-hour. So for Eos to come out of nowhere and sell at $160 per kilowatt-hour has many in the industry understandably suspicious.

Of course, there is a difference between what a company sells its batteries for and what it costs to make them. Right now, Eos lacks the production volume to capitalize on economics of scale. Bouchard didn't comment on the exact costs of manufacturing, but he did say this: "For the volumes we have contracted already for 2017, we’re profitably manufacturing and selling batteries."

He added that the company knows what costs will be at volume, and it expects to be a profitable in 2018. Last October, Eos raised $23 million to scale its technology. Prior to that, the company raised $23 million in May 2015 and about $27 million in two previous funding rounds.

"Emerging technologies that cost more than lithium-ion today, we expect will have a tough time," Oster said. "We think we have enough of a cost advantage that we’ll be able to sell a good volume this year."

The strategy, then, is to lure customers to a new technology with eye-popping prices, and bolster the sale with the credibility of established players like Siemens and Northern Power. The competition will be scrutinizing whether those price quotes look as good in real life as they do on paper. As for whether the company can profitably sustain such prices, we'll have to wait and see.

*A previous version of this article employed a rhetorical device suggesting that nobody had heard of this technology. In fact, the author, the technology's inventors and observers of this market are aware of its existence.**The wording has been updated to clarify the extent of Siemens' involvement with Eos batteries.