- 1. The device must be safe, environmentally benign, and efficient
- 2. The resources must exist to build the devices
- 3. The device should cost no more than the lowest cost of an alternative energy source such as gas-fired turbines.
ZAI’s zinc – iron flow battery consists of a zinc / zincate anode, a cathodic iron anion complex in an aqueous alkaline supporting electrolyte, and proprietary high efficiency electrodes in a stack configuration that allows parallel electrolyte feeds without significant shunt losses. The selection of chemistry permits the use of common and low cost materials such as zinc oxide, iron salts, polypropylene, steels, and nickel coatings. The electrochemistry has round-trip energy efficiency comparable to lithium ion, yet as a water-based electrolyte, provides unsurpassed safety. The low cost, safety, and efficiency inherent to this system thereby provides a natural scalability to the megawatt-hour range and above.
The commercialization of the ZAI Zinc – Iron battery has focused on three critical areas:
- Electrodes: ZAI has developed high efficiency (low polarizing at low flowrates and low gassing) electrode designs and alloys that improve the cost of operation of the battery. Consequently, these electrodes allow high power charge and discharge that makes the designs suitable for a variety of revenue streams.
- Electrolytes: Low-cost aqueous electrolyte blends have been developed that improve the deposition quality of zinc and thus capacity and allows extended reliable service. In addition, these electrolyte blends allow higher concentrations of metal salts without the associated problems of precipitation.
- Manifolds: A manifolding system has been developed that minimizes parasitic shunt currents without impeding flow significantly.
It is proposed in this presentation that the energy needs for the world can be reconciled with a combination of RES’s and large scale storage. Zinc is a logical a cost-effective means to achieve this and will allow regional interests to generate their own grid infrastructure with the natural resources at hand. In particular, ZAI’s Z-20 family of products can meet these needs with both high power and high capacity cells suitable for large-scale deployment on the electrical grid, and provides the lowest-risk path to stable carbon emissions, energy security, and the establishment of a safe means to develop our nation.