Sorry, you need to enable JavaScript to visit this website.

Flow-Assisted Alkaline Battery

City University of New York (CUNY) Energy Institute
ARPA-E Award: 
New York, NY
Project Term: 
09/15/2010 to 03/31/2015
Project Status: 
Technical Categories: 
Graphic of CUNY's technology
Critical Need: 

Our national electric grid has limited ability to store excess energy, so electricity must constantly be over-generated to assure reliable supply. Though wind and solar power are promising clean alternatives to fossil fuels, their natural unpredictability and intermittency present major challenges to delivery of the consistent power that is necessary to operate today's grid. The U.S. needs technologies that can store renewable energy for future grid-use at any location. Flexible, large-scale storage would create a stronger and more robust electric grid by enabling renewables to contribute to reliable power generation.

Project Innovation + Advantages: 

City University of New York (CUNY) Energy Institute is working to tame dendrite formation and to enhance the lifetime of Manganese in order to create a long-lasting, fully rechargeable battery for grid-scale energy storage. Traditional consumer-grade disposable batteries are made of Zinc and Manganese, two inexpensive, abundant, and non-toxic metals, but these disposable batteries can only be used once. If they are recharged, the Zinc in the battery develops filaments called dendrites that grow haphazardly and disrupt battery performance, while the Manganese quickly loses its ability to store energy. CUNY Energy Institute is also working to reduce dendrite formation by pumping fluid through the battery, enabling researchers to fix the dendrites as they form. The team has already tested its Zinc battery through 3,000 recharge cycles (and counting). CUNY Energy Institute aims to demonstrate a better cycle life than lithium-ion batteries, which can be up to 20 times more expensive than Zinc-based batteries.

Potential Impact: 

If successful, CUNY Energy Institute's project would put the U.S. on a path towards creating a smarter grid with low-cost batteries that are capable of storing enough electricity to power homes, cars, and cities.


A more efficient and reliable grid would be more resilient to potential disruptions.


Electricity generation accounts for over 40% of U.S. carbon dioxide (CO2) emissions. Enabling large-scale contributions of wind and solar power for our electricity generation would result in a substantial decrease in CO2 emissions.


Increases in the availability of wind and solar power would reduce fossil fuel demand, resulting in reduced fuel prices and more stable electricity rates.

Innovation Update: 
(As of May 2016) 
In 2013 the members of the CUNY team founded a battery startup, Urban Electric Power (UEP), which is supported by private venture and strategic investors. As of early 2016, UEP offers two grid storage products based on CUNY’s technology developed under its ARPA-E award: a 2 to 50kWh standalone storage system for residential and commercial backup power in developing countries and a rack-mounted storage unit for use in utility-scale (more than 100kWh) storage applications. UEP began shipping small “test units” for potential customers to evaluate in early 2015 and they began shipping their standalone storage system for residential and commercial backup power to customers in late 2015. 
CUNY built off of previous work addressing the issue of dendrite formation to solve the problem of irreversible chemical changes in manganese that cause rapid loss of cell capacity. In order to deliver a controlled depth of discharge, the team developed a sophisticated battery management strategy and optimized the composition and structure for the cathode (positive electrode). Through these innovations, the team demonstrated high life cycle with the new cathode. To simplify balance of plant and lower system cost, the team also developed a new approach to the zinc-dendrite problem. The team further improved the performance by modifying the anode microstructure, incorporating novel cell additives, and testing new separator materials. Final cells, incorporating both the improved anode and cathode, cycled over 1,000 times, with projected lifetimes of 5,000 cycles. 
For a detailed assessment of the CUNY project and impact, please click here.

ARPA-E Program Director: 
Dr. John Lemmon
Project Contact: 
Michael Adams
Release Date: