StorEn Technology* is developing a new generation of vanadium flow batteries to meet the growing market demand for cost-effective energy storage.
Unlike conventional batteries that store their reactive materials within their cells, vanadium flow batteries are a type of rechargeable battery in which the energy is stored chemically in a liquid electrolyte contained in two tanks.
Stor.En has developed Multigrid™ technology that improves the electrical efficiency of the stack, helping reduce costs for storage solutions for residential, industrial, or utility needs.
The following is an interview with StorEn’s Chief Technology Officer, Angelo D’Anzi
Vanadium flow technology has been around for a while: what makes Stor.En’s technology different?
Vanadium batteries are the best technology for stationary energy storage application. This is a proven technology with features like long-scale duration (sometimes in excess of 20 years) with no self-discharge and memory effect or ghost effect that always runs at 100% discharge.
People considering installing storage in their home most likely have come across lithium ion batteries, such as the Tesla Powerwall™. It is understood that a lithium ion battery, despite having a 10-year warranty, will lose some of its original capacity over time. We have all experienced with our laptops and mobile phones – this decay in capacity can be in excess of 50% after only three years.
With lithium ion batteries, the user may be forced to install additional capacity to compensate for their decay. But vanadium flow batteries offer 100% capacity for a lifespan of 25 years.
Why is vanadium flow technology underutilized?
In the 1990s, the major interest was for smaller and lighter batteries for use in the automotive industry and portable devices like laptop computers and phone. Despite the long duration of vanadium flow batteries, they are too big for these types of applications.
Of course, there is one battery technology that is best for all applications. And while lithium leads for applications in mobility, we believe vanadium flow is the best option for stationary applications where size is not an issue. This is especially important now, as we look towards a growing generation from all renewables and the importance of storage capacity. In this case, size is not important, but long duration and lowest cost per cycle is imperative.
How can you achieve such a low cost per kWh?
Cost is crucial for the adoption of energy storage. Our work is about bringing evolution to the technology with the objectives to improve performance as a way to drive down costs. We developed a disruptive battery technology based on both chemical and engineering solutions, leading to a 50% cost reduction. We are targeting a price of $400/kWh with a 25 year duration with no decay.
The great breakthrough is our innovative high-power electrodes made with nanomaterials and a proprietary functionalization process. With this innovation we have doubled power density over traditional batteries, while running at low pressure.
The ability to run at low pressure means that less of the battery’s own energy is required to run the pumps, hence round-trip efficiency is increased. Additionally, duration of the battery is also increased. To support the electrochemical activity, we couple our Hi-Power Nano-Structured Carbon Electrode to our MULTIGRID™ multipoint flow distribution to deliver an increase in power in excess of 50%.
We also wanted to make a battery that was virtually maintenance-free, like a car battery, for trouble-free operations and reduced Total Costs of Ownership. We developed two proprietary systems, RESAFE™ and EQUILEVELS™. These two systems support a battery that is virtually maintenance-free by eliminating service activities.
Our battery can be monitored remotely with our built-in BMS (Battery Management System). Therefore we implement a shift from scheduled on-site inspections to a maintenance-on-demand model. For example, if one of our batteries was installed in a remote telecommunications tower for power back-up, remote monitoring can reduce or eliminate the need for periodic on-site visits, which can translate in significant cost savings.
In which applications do you see your innovation able to deliver the greatest benefits?
Our vanadium batteries can satisfy several needs, from power backup to energy storage. Our technology is already financially viable in several of these applications with the world’s lowest cost per cycle of $0.02.
Would you target residential applications, like Tesla does with the Powerwall™?
In residential installations, the greatest benefit is the 25-year lifespan coupled with consistent performance over time, while a Powerwall comes with only a 10-year warranty
Furthermore, our chemistry is safe. It is non-flammable and non-explosive, unlike lithium batteries. In a residential installation, this is a crucial consideration so as to avoid fire hazards.
We also also developed a geothermal design that we’ve named THERMASTABLE™. This design increases the round-trip efficiency of our batteries, making them resilient in case of natural disasters, like the recent hurricanes that occurred in the US.
Are you concerned about a possible surge in the price of vanadium?
But vanadium is abundant. In any case, StorEn is negotiating with a mining company a long-term contract to secure a consistent supply of vanadium at a capped price.
When are you coming to market with your batteries?
We have completed our R&D and are ready to start commercialization of our batteries. We are targeting a quick advancement into the market, hoping to be available in late 2019. Our first target market is US first, then in other geographies via a network of local industrial partners. Several contacts and Framework Agreements are under negotiation.
This post was supported by Stor.En Technologies; images courtesy of the company