Bipolar Nickel Metal Hydride Batteries Research Articles

Electrochemical Energy Storage Devices in Pulsed Power

Numerous research efforts have been undertaken to improve the feasibility of fielding compact pulsed power systems for a wide variety of applications. Each of these research efforts focuses on specific areas of pulsed power, but few papers have focused on the performance of a grid independent prime power source. This critical component is often overlooked in mobile pulsed power systems. Though not within the pulsed power community, a great deal of work has been performed by those in the electrochemical energy storage community to improve the energy density, power density, working voltage, and cycle life of electrochemical cells. This paper has helped to develop new energy storage technologies for applications such as consumer electronics, electric vehicles, and electrical grid energy storage. However, these electrochemical cells were not developed with pulsed power applications in mind. For that reason, a large amount of research is needed to understand how to effectively use electrochemical cells in pulsed power applications. In this paper, a number of different energy storage chemistries, including lithium-ion batteries, lead acid batteries, and bi-polar nickel metal hydride batteries, have been evaluated for use in pulsed power applications as a result of their high power and energy densities.

Degradation mechanisms of high-energy bipolar nickel metal hydride battery with AB5 and A2B7 alloys

Abstract The failure modes of nickel/metal hydride batteries made from conventional AB 5 and La-only Mg-containing A 2 B 7 metal hydride alloys were studied at the end of 70% state-of-charge cycle life testing (reaching below 3.1 Ah capacity in a 5.5 Ah design cell) by the combination of inductively coupled plasma, scanning electron microscope, X-ray energy dispersive spectroscopy and composition mapping, and X-ray diffraction analysis. The capacity degradation of cell with AB 5 alloy was found to have been caused by the combination of metal hydride alloy oxidation and non-reversible γ-NiOOH phase formation, which was promoted by the incorporation of Al leached out from the oxidation product of the Al-containing negative electrode. In the cell with Al-free A 2 B 7 alloy, the end of cycle life was the result of pulverization in the main A 2 B 7 phase.

Transportation Bipolar Ni-MH Battery

A novel bipolar packaging design for a nickel metal hydride (NiMH) battery has been developed. As with other bipolar designs, advantages include reduced battery resistance and volume when compared with more conventional approaches. These advantages make the bipolar NiMH an excellent energy and power source for existing and emerging high voltage, high power applications. In this paper, we give an account of our recent experiences with the design, with a focus on designs for high power batteries for hybrid electric vehicles and high energy batteries for plug-in hybrids. In addition, we discuss results from a hybrid electric vehicle to plug-in hybrid electric vehicle conversion utilizing a high energy bipolar NiMH battery. The conversion and results demonstrate the successful implementation of the battery design in an automotive application.

Fabrication of bipolar nickel metal hydride batteries with nanometer copper oxide as anodic additive

The bipolar nickel metal hydride batteries were fabricated with a novel anodic additive of nanometer copper oxide. Cycle voltammetry indicated that the nanometer copper oxide in the anode electrode was reduced to copper in the first charge, and SEM and EDS proved the sphere copper particles deposited on the alloy surface and stably existed in the next cycles. EIS results revealed the lower contact resistance and charge transfer resistance of the nanomaterial added anode electrode. Moreover, the bipolar battery with the nanometer additive displayed excellent electric performance and increased specific energy and power in electrochemical tests, which made it better meet the requirement of power sources for electric and hybrid vehicles. The present work has provided a novel additive of the anode electrode to effectively improve the performance of the bipolar Ni/MH batteries.

Investigations into a battery management for high power nickel metal hydride batteries

Bipolar nickel metal hydride batteries are of interest for intermediate power storage in hybrid electric vehicles. The special design allows to gain additional information on the state of charge (SOC). In order to keep a nickel metal hydride battery in a limited SOC range a battery management system is required. The influence of external conditions, like temperature, mode of operation and load profile to the quality of the operation of the quality of the battery management system are discussed.

Pulse power 350 V nickel–metal hydride battery power-D-005-00181

Energy-storage devices are needed for applications requiring very high-power over short periods of time. Such devices have various military (rail guns, electromagnetic launchers, and DEW) and commercial applications, such as hybrid electric vehicles, vehicle starting (SLI), and utility peak shaving. The storage and delivery of high levels of burst power can be achieved with a capacitor, flywheel, or rechargeable battery. In order to reduce the weight and volume of many systems they must contain advanced state-of-the-art electrochemical or electromechanical power sources. There is an opportunity and a need to develop energy-storage devices that have improved high-power characteristics compared to existing ultra capacitors, flywheels or rechargeable batteries. Electro Energy, Inc. has been engaged in the development of bipolar nickel–metal hydride batteries, which may fulfil the requirements of some of these applications. This paper describes a module rated at 300 V (255 cells) (6 Ah). The volume of the module is 23 L and the mass is 56 kg. The module is designed to deliver 50 kW pulses of 10 s duration at 50% state-of-charge. Details of the mechanical design of the module, safety considerations, along with the results of initial electrical characterization testing by the customer will be discussed. Some discussion of the possibilities for design optimization is also included.

Bipolar nickel-metal hydride battery for hybrid vehicles

Hybrid electric vehicles are receiving increased interest as an approach to decrease vehicle pollution, dependence, and consumption of liquid petroleum and meet forthcoming Government vehicle emission standards. A number of schemes are under consideration (heat engine battery, fuel cell battery, peaking battery, inner-city battery, etc.). The success of any of the approaches will be dependent on battery capabilities, i.e., power, density, life, and cost. The nickel-metal hydride system appears to be the most promising of the candidate battery chemistries. Preliminary designs and analysis have been prepared and are presented for various configurations. Initial performance characterization tests are presented. It is concluded that a bipolar package arrangement for the Ni-MH chemistry appears most suited for the hybrid vehicle application considered. >