Nickel-zinc (NiZn) batteries are chemically similar to nickel-metal hydride. Both use an alkaline electrolyte and a nickel electrode but differ significantly in their voltage. The NiZn cell delivers more than 0.4V of additional voltage both at open circuit and under load.
MH + NiOOH = M + Ni(OH)2
H2O + Zn + 2NiOOH = ZnO + 2Ni(OH)2
With the additional 0.4V per cell, an inherent value of the NiZn cell lies in the reduced cell count required for a multi-cell battery. For higher voltage applications the advantages associated with fewer cells are quickly apparent through a smaller footprint, lighter weight, and lower impedance battery.
Before ZincFive was able to make available the advantages of the NiZn battery chemistry they needed to solve the technical problems associated with the instability of the zinc electrode in a rechargeable cell. The cornerstone of this solution was found in a patented electrolyte formulation that reduces zinc solubility and prevents dendrite shorting problems.
The capabilities of the cell were further enhanced with patented advancements in both the positive and negative electrode composition that eliminate the inclusion of toxic material. Additionally, the company has a strong and broad intellectual property position that addresses all major aspects of the cell chemistry as well as engineering and construction details that enable the use of existing nickel-metal hydride manufacturing equipment for production of the cells.
High power densities up to 3000W/kg are facilitated by fast zinc electrode kinetics, highly conductive substrates and a highly ionically conductive alkaline electrolyte.
These high power densities can be achieved while maintaining energy densities in excess of 70 Wh/kg.
The technology is inherently safe and able to withstand all standard automotive abuse tests without incident even in battery sizes exceeding 100Ah.
NiZn is one of the most recyclable battery chemisteries on the market. Unlike many other materials, both nickel and zinc can be recycled again and again while maintaining their physical and chemical properties, as there remains the same amount of each element at the end of a particular product cycle as at the beginning.
NiZn Technology Benefits
By significantly extending the cycling capability of a NiZn battery without compromising the high-performance properties inherent to the chemistry, ZincFive has introduced a rechargeable battery featuring a wide range of customer benefits over lead-acid and lithium-ion batteries.
High Energy Density - The ZincFive high-discharge battery offers dramatically higher energy density than lead-acid batteries and comparable energy density to high power lithium-ion batteries when measured by either weight (Watt hours per kilogram) or by volume (Watt hours per liter).
Superior Power Density - The ZincFive high discharge battery delivers a higher voltage in a smaller and lighter package than other rechargeable batteries. This reduces the size of the NiZn battery to less than half the size of a typical lead-acid battery.
Lower Cost - Inherently less expensive, zinc provides a significant total cost of ownership savings over other rechargeable batteries.
Safety - NiZn battery chemistry has environmental and physical safety advantages over lead-acid and lithium-ion batteries. Both nickel and zinc are recycled easily. The zinc electrode contains no lead, cadmium or mercury, and presents no threat to the environment. NiZn batteries are non-flammable and fail-safe and therefore are not subject to the travel restrictions placed on lithium ion products. NiZn batteries are recommended in applications where physical safety is essential.
Charge/Discharge Rate - The NiZn battery chemistry excels at high discharge rates while retaining thermal stability and is also capable of fast recharging , a key benefit for many applications including uninterruptible and motive power where high charge acceptance is necessary.
Cycle Life - ZincFive’s NiZn battery offers more than twice the cycle life of typical lead-acid batteries and competes well with lithium-ion cycle life in many applications.
Long Shelf Life - Superior to lead-acid batteries which will sulfate over time, limiting their shelf life. The ZincFive NiZn high discharge battery has a significantly longer shelf life and requires no trickle charging to maintain capacity performance.