N211-053 TITLE: Nickel-Zinc Submarine Main Storage Battery
RT&L FOCUS AREA(S): General Warfighting Requirements
TECHNOLOGY AREA(S): Electronics
OBJECTIVE: Develop a Nickel-Zinc (NiZn) battery system that does not rely on Lithium Ion (Li-ion) technology and would replace lead-acid battery system with a more efficient, environmentally safe, maintenance free, and long life battery in the form of a large-format (1,000Ah+) NiZn battery with cycle life and capacity maximized within the design.
DESCRIPTION: The U.S. Navy Submarine Fleet main storage battery currently employs Valve-Regulated Lead-Acid (VRLA) technology to meet platform energy and power requirements. However, with the increasing reliance of electronics on large platforms, future mission needs will require additional battery capacity beyond what current lead-acid battery technology is able to provide. The submarine battery compartment cannot be expanded, so VRLA technologies have seemingly reached operational limits. Therefore, there is a mounting need to transition from the current VRLA battery to an alternative battery technology with a higher energy density and improved reliability. Accordingly, NiZn battery technology has the potential to bridge the energy density gap until Li-ion battery technology can be made reliably safe for submarine applications. Further, submarines continue to see electrical load growth requiring more main storage battery capacity in the same volume. The development of a large-format NiZn battery will offer the needed battery capacity increase on submarines while offering a safer alternative to Li-ion batteries, which, though energy dense, come with a high risk of failure. A Li-ion failure onboard a submarine has the potential to be a catastrophic event. The Navy could potentially delay, or eliminate altogether, a Li-ion transition requirement allowing for lower risk design cycle.
NiZn is an emerging battery technology optimized for high capacity and long life while also delivering high power in an environmental friendly and safe chemistry. NiZn batteries have a projected increase of about 50% the capacity of lead-acid batteries, with a 25% weight reduction given the same footprint. Currently, prototype and commercial NiZn batteries are of small-format design. Large-format, scaled-up versions of the NiZn designs are not commercially available. Submarine main storage battery replacement will require scale-up of small-format NiZn technology to submarine-specific sized large-format 1,000Ah+ NiZn batteries with cycle life and capacity maximized within the design. The NiZn battery concept must achieve 75% of capacity through 200+ Navy Equivalent Charge/Discharge cycles. Feasibility of concept will be determined through various characterization and operational testing at NSWC Crane. The developed and delivered prototype large-format batteries will be provided to NSWC Crane at the end of Phase II for testing and evaluation. NSWC Crane has the expertise to test and aid development of large-format NiZn batteries using lessons learned from VRLA efforts. The focus of testing at Crane will be to validate the performance of the large-format batteries through characterization and Operational Cycle Life (OCL) testing. OCL will be performed to evaluate the ongoing performance and expected cycle life of the design by pushing the prototypes through various charge and discharge rates over a period of 200+ Navy Equivalent Cycles (NECs). The prototypes will be tested to obtain performance data and demonstrate viability of NiZn as a replacement for Submarine VRLA main storage battery.
PHASE I: Develop a minimum 1,000 amp-hour NiZn battery concept that can achieve 75% of capacity through 200+ Navy Equivalent Charge/Discharge cycles. Develop a design and fabrication approach to scale small-format NiZn to large-format and determine technical feasibility. The initial design concept should include expected cycle life, performance, and manufacturability of large-format NiZn cells and batteries. Feasibility of concept will be determined through various characterization and operational testing at NSWC Crane. The Phase I Option, if exercised, will include the initial design specifications and capabilities description to build a prototype in Phase II.
PHASE II: Develop and deliver a prototype large-format NiZn cells and batteries based on Phase I work and Phase II Statement of Work (SOW) for demonstration, testing and validation which will include characterization testing to understand the range of capacities through various discharge rates as well as operational testing to validate long-term performance. Prototype will be provided to NSWC Crane at the end of Phase II for testing and evaluation.
PHASE III DUAL USE APPLICATIONS: Utilize the Phase II prototype testing and analysis results to assist the Navy in transitioning to Navy use. Update design and system development. Integrate Battery Management System (BMS) requirements (furnished by the Navy based on results of testing and evaluation) into final NiZn large-format cells and batteries.. Implement full-scale design manufacturing and transition the end product to the Navy for submarine main storage battery validation, testing, qualification, and certification at NSWC Crane with PMS 392 support.
This technology has potential commercial transition to other applications such as aircraft, alternative energy, and data center energy storage. Large-scale NiZn batteries can easily be integrated in current lead-acid applications such as engine start, trucking, and large-scale data centers.
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KEYWORDS: Submarine Main Storage Battery; Nickel-Zinc Battery; Nickel-Zinc Replace Lead-Acid; Nickel-Zinc Alternative Energy; Rechargeable Nickel-Zinc Batteries; Safer Alternative to Lithium-ion.