Search NASA⌕ Search

SEARCH · Search NASA

Results for “battery life”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS2006

The 2004 NASA Aerospace Battery Workshop

Topics covered include: Super NiCd(TradeMark) Energy Storage for Gravity Probe-B Relativity Mission; Hubble Space Telescope 2004 Battery Update; The Development of Hermetically Sealed Aerospace Nickel-Metal Hydride Cell; Serial Charging Test on High Capacity Li-Ion Cells for the Orbiter Advanced Hydraulic Power System; Cell Equalization of Lithium-Ion Cells; The Long-Term Performance of Small-Cell Batteries Without Cell-Balancing Electronics; Identification and Treatment of Lithium Battery Cell Imbalance under Flight Conditions; Battery Control Boards for Li-Ion Batteries on Mars Exploration Rovers; Cell Over Voltage Protection and Balancing Circuit of the Lithium-Ion Battery; Lithium-Ion Battery Electronics for Aerospace Applications; Lithium-Ion Cell Charge Control Unit; Lithium Ion Battery Cell Bypass Circuit Test Results at the U.S. Naval Research Laboratory; High Capacity Battery Cell By-Pass Switches: High Current Pulse Testing of Lithium-Ion; Battery By-Pass Switches to Verify Their Ability to Withstand Short-Circuits; Incorporation of Physics-Based, Spatially-Resolved Battery Models into System Simulations; A Monte Carlo Model for Li-Ion Battery Life Projections; Thermal Behavior of Large Lithium-Ion Cells; Thermal Imaging of Aerospace Battery Cells; High Rate Designed 50 Ah Li-Ion Cell for LEO Applications; Evaluation of Corrosion Behavior in Aerospace Lithium-Ion Cells; Performance of AEA 80 Ah Battery Under GEO Profile; LEO Li-Ion Battery Testing; A Review of the Feasibility Investigation of Commercial Laminated Lithium-Ion Polymer Cells for Space Applications; Lithium-Ion Verification Test Program; Panasonic Small Cell Testing for AHPS; Lithium-Ion Small Cell Battery Shorting Study; Low-Earth-Orbit and Geosynchronous-Earth-Orbit Testing of 80 Ah Batteries under Real-Time Profiles; Update on Development of Lithium-Ion Cells for Space Applications at JAXA; Foreign Comparative Technology: Launch Vehicle Battery Cell Testing; 20V, 40 Ah Lithium Ion Polymer Battery for the Spacesuit; Low Temperature Life-Cycle Testing of a Lithium-Ion Battery for Low-Earth-Orbiting Spacecraft; and Evaluation of the Effects of DoD and Charge Rate on a LEO Optimized 50 Ah Li-Ion Aerospace Cell.

Source record↗
DOE OSTI2021

Depowering of Batteries to Reduce Cost of Ownership

(1) Executive Summary: End of life batteries (EOLBs) present a cost and safety liability for their owners and stakeholders. This is due flammability, energy, and power with EOLBs. Current approaches include cumbersome, expensive packaging, specialized shipping, regulated storage, and they are responsible for over half of the cost of recycling. They all expensively and inadequately address symptoms. OnTo has developed and proven a simple way to resolve the problem systemically, through depowering of lithium-ion batteries (and most any battery other than lead). The low-cost process removes flammability, power, and energy in EOLBs through non-toxic chemical processing. The opportunity for commerce of inert scrap is at least $5 billion greater than the commerce in hazardous scrap, all made possible through OnTo’s technology for efficiency and safety. (2) Depowering Improves Safety and Decreases Cost of Battery Ownership: OnTo’s depowering technology will remove half of the cost of EOLB management and recycling. Without this technology, EOLB recycling will always be a liability. EOLB is hazardous due to inherent flammability of electrolyte and lithium. The shipping and commerce of EOLBs is costly and dangerous all along the chain of custody from owner, dealership/shop, shipper, second-life sorter, (shipper again), and finally to the destination facility recycler. OnTo’s depowering service renders inert most any EOLB packs, modules, and cells. The technology uses a brief, non-toxic treatment applicable to most any chemistry. The industry needs a safe, simple, modular, and inexpensive method to render EOLBs as inert scrap. OnTo’s deactivation system is scalable to the needs of any customer along the EOLB chain of custody. (3) Evidence of Successful Depowering: Untreated batteries will catch fire and explode under abuse conditions such as heat or crush. Slide 2 below shows that untreated batteries will blow-up and expel their internal components with heating, after OnTo’s depowering treatment, the same battery is inert with the same heat treatment (Fig. 7 in the slide). Depowering also removes electrolyte reactivity, eliminating the production of HF and other toxins (Fig 6. in the slide) The depowering process is applicable to large, 26 Ah cells. Fig. 5 in the slide shows the removal of all the electrolyte from whole cells. Removal of flammable material from an EOLB contributes to the inert behavior. OnTo developed this technology through a project supported by the US Department of Energy EERE program, with partners including Seattle King County Metro Transit. While OnTo has generated evidence of successful depowering of batteries, in 2020, a follow-on voucher opportunity for third party analysis of depowered cells and materials was approved through CalTestBed. The expertise of the battery and materials research groups at Lawrence Berkeley National Laboratory will characterize these depowered cells to provide better understanding of the materials level changes in depowering. (4) Pilot Plant for Depowering EOLBs: Making the spoke work in hub-and-spoke While other companies are marketing the hub-and-spoke approach for recycling EOLBs, they rely on dangerous, expensive shredding methods with flimsy IP protection. OnTo offers the only patented, proven ability to depower EOLBs from most any chemistry – at half of the capital cost required for shredding, while eliminating the liability, danger, and waste streams inherent with shredding. The proposed commercial pilot facility is (5) OnTo Technology LLC Company: OnTo develops advanced battery recycling innovations that produce manufacturing quality electrode materials from recycled batteries. Their patented Cathode-healing™ and Deactivation/Depowering processes improve safety and reduce the cost of recycling. OnTo’s breakthrough technologies produce advanced materials for manufacturing batteries useful in applications from portable power to electric vehicles. Contact: Steve Sloop OnTo Technology LLC, 63221 Service Road, STE F, Bend, OR 97703, ssloop@onto-technology.com , 541-389-7897

deactivation↗
NASA NTRS1985

Deep reconditioning of batteries during DSCS 3 flight operations

Deep reconditioning of batteries is defined as discharge below the 1.0 volt/cell level to a value of about 1.0 volt/battery. This type of reconditioning was investigated for use on the Defense Satellite Communications System (DSCS) spacecraft, and has been used during the first year of orbital operation. Prior to launch of the spacecraft, the deep reconditioning was used during the battery life test, which has now complete fourteen eclipse periods. Reconditioning was performed prior to each eclipse period of the life test, and is scheduled to be used prior to each eclipse period in orbit. The battery data for discharge and recharge is presented for one of the life test reconditioning cycles, and for each of the three batteries during the reconditioning cycles between eclipse period no.1 and eclipse period no.2 in Earth orbit.

Thierfelder, H. E.↗
NASA NTRS1979

Design tradeoff studies and sensitivity analysis, appendix B

Further work was performed on the Near Term Hybrid Passenger Vehicle Development Program. Fuel economy on the order of 2 to 3 times that of a conventional vehicle, with a comparable life cycle cost, is possible. The two most significant factors in keeping the life cycle cost down are the retail price increment and the ratio of battery replacement cost to battery life. Both factors can be reduced by reducing the power rating of the electric drive portion of the system relative to the system power requirements. The type of battery most suitable for the hybrid, from the point of view of minimizing life cycle cost, is nickel-iron. The hybrid is much less sensitive than a conventional vehicle is, in terms of the reduction in total fuel consumption and resultant decreases in operating expense, to reductions in vehicle weight, tire rolling resistance, etc., and to propulsion system and drivetrain improvements designed to improve the brake specific fuel consumption of the engine under low road load conditions. It is concluded that modifications to package the propulsion system and battery pack can be easily accommodated within the confines of a modified carryover body such as the Ford Ltd.

Source record↗
NASA NTRS2006

Hubble Space Telescope 2004 Battery Update

Battery cell wear out mechanisms and signatures are examined and compared to orbital data from the six on-orbit Hubble Space Telescope (HST) batteries, and the Flight Spare Battery (FSB) Test Bed at Marshall Space Flight Center (MSFC), which is instrumented with individual cell voltage monitoring. The on-orbit HST batteries were manufactured on an expedited basis after the Challenger Shuttle Disaster in 1986. The original design called for the HST to be powered by six 50 Ah Nickel Cadmium batteries, which would have required a shuttle mission every 5 years for battery replacement. The decision to use NiH2 instead has resulted in a longer life battery set which was launched with HST in April 1990, with a design life of 7 years that has now exceeded 14+ years of orbital cycling. This chart details the specifics of the original HST NiH2 cell design. The HST replacement batteries for Service Mission 4, originally scheduled for Spring 2005, are currently in cold storage at NASA Goddard Space Flight Center (GSFC). The SM4 battery cells utilize slurry process electrodes having 80% porosity.

Hollandsworth, Roger↗
NASA NTRS1989

Hubble Space Telescope six-battery nickel-cadmium mission simulation test

A simulation test of the six-battery nickel-cadmium mission to determine battery life and electrical power system (EPS) performance characteristics for the Hubble Space Telescope (HST) program, is described. The basic HST power system requirements are to provide power generation, energy storage, and EPS control and distribution for 2.5 years with the nickel-cadmium (NiCd) batteries at an end of life solar array of 2 years. Mission simulation life testing begain in April of 1986, and the batteries have completed their 2.5 year mission requirement. Conditions as close as practical to the actual predicted mission profiles were used. These included solar array degradation, load variations, beta angle changes, temperature changes (with excursions to 10 C), battery reconditioning, safemode simulations, and off-normal roll activities. Discounting system cycling interruptions caused by hardware, software, human error, and periodic updates and revisions, the HST EPS breadboard hardware operated continuously for 30 months and demonstrated the power system's ability to meet the HST requirement.

Jackson, Lorna G.↗
NASA NTRS1985

Design Evaluation of High Reliability Lithium Batteries

Within one year, a lithium battery design can be qualified for device use through the application of accelerated discharge testing, calorimetry measurements, real time tests and other supplemental testing. Materials and corrosion testing verify that the battery components remain functional during expected battery life. By combining these various methods, a high reliability lithium battery can be manufactured for applications which require zero defect battery performance.

Buchman, R. C.↗
NASA NTRS1994

Nickel cadmium battery operations and performance

The Earth Radiation Budget Satellite (ERBS), Compton Gamma Ray Observatory (CGRO), Upper Atmosphere Research Satellite (UARS), and Extreme Ultraviolet Explorer (EUVE) spacecraft are operated from NASA's Goddard Space Flight Center (GSFC) in Greenbelt, Maryland. On-board power subsystems for each satellite employ NASA Standard 50 Ampere-hour (Ah) nickel-cadmium batteries in a parallel configuration. To date, these batteries have exhibited degradation over periods from several months (anomalous behavior, UARS and CGRO (MPS-1); to little if any, EUVE) to several years (old age, normal behavior, ERBS). Since the onset of degraded performance, each mission's Flight Operations Team (FOT), under the direction of their cognizant GSFC Project Personnel and Space Power Application Branch's Engineers has closely monitored the battery performance and implemented several charge control schemes in an effort to extend battery life. Various software and hardware solutions have been developed to minimize battery overcharge. Each of the four sections of this paper covers a brief overview of each mission's operational battery management and its associated spacecraft battery performance. Also included are new operational procedures developed on-orbit that may be of special interest to future mission definition and development.

Rao, Gopalakrishna↗
NASA NTRS2005

Technical Consultation of the Hubble Space Telescope (HST) Nickel Hydrogen (NiH2) Battery Charge Capacity Prediction

The purpose of the GSFC position paper is to identify critical HST milestone dates for continued science studies followed by the attachment of a re-entry module or a robotic servicing mission. The paper examines the viability of the HST with respect to the NiH2 continued battery charge capacity. In the course of the assessment, it was recognized that the HST battery thermal control system has an average heat dissipation limitation of 30 W per bay per orbit cycle. This thermal constraint will continue to govern options for battery capacity maintenance. In addition, the HST usage represents the longest exposure ofNiH2 batteries to Low Earth Orbit (LEO) at the current level of Depth of Discharge (DOD). Finally, the current battery life is at the limit predicted by the manufacturer, Eaglepicher. Therefore, given these factors, the potential exists that the HST battery capacities could radically degrade at any point. Given this caveat on any life extrapolations, the conservative model proposed in the GSFC position paper was viewed by the NESC as having several technical assumptions such as limited utilization of flight battery capacity data, the susceptibility of the proposed prediction method to large variations when supplemented with additional information, and the failure to qualitatively or quantitatively assess life prediction sensitivities. The NESC conducted an independent evaluation of the supporting information and assumptions to generate the predictions for battery capacity loss and practicality of on-orbit battery conditioning.

Gentz, Steven J.↗
DOE OSTI2020

Mitigating the Impact of Thermal Binder Removal for Direct Li-Ion Battery Recycling

Li-ion battery recycling will become critical to the management of end-of-life batteries from electric vehicles. Currently, it is a challenge to create a profitable recycling process, which is made more difficult by the reduction in cathode cobalt content. Maintenance of the cathode structure throughout the recycling process can yield increased revenues that may make recycling profitable. This method will require careful removal of the PVDF binder and carbon black, which can be achieved through thermal processing. Furthermore, it is necessary to mitigate the effects of the fluorine from the PVDF on the cathode material. Herein, we report a process that utilizes excess LiOH•H 2 O to react with this fluorine and thereby prevent lithium removal and doping of the cathode material. In addition, we demonstrate a one-step thermal process that can both remove the binder and relithiate the cathode material.

25 ENERGY STORAGE↗
NASA NTRSDate not supplied

Li-ion Battery Aging with Hybrid Physics-Informed Neural Networks and Fleet-wide Data

In this work, we propose a hybrid model for Li-ion battery discharge and aging prediction that leverages fleet-wide data to predict future capacity drops.The model is built upon an hybrid approach merging physics-based and empirical equations, as well as neural network models in a recurrent neural network cell. The hybrid physics-informed neural network can predict voltage discharge cycles given the loading profile, and estimate the used capacity of the battery under random-loading conditions by tracking aging parameters connected to the residual capacity of the battery. By merging information on the battery aging parameters with existing fleet-wide aging data, the model can predict the future residual capacity of the battery that is being monitored, and therefore enable predictions of voltage discharge curves far ahead in the battery life cycle. We validated the approach using the NASA Prognostics Data Repository Battery data-set, which contains experimental data on Li-ion batteries discharged at random loading conditions in a controlled environment. The approach also allows the identification of discrepancies between the battery aging trend and the trend observed at the fleet level, so that batteries behaving differently from the rest of the fleet can be subject to closer monitoring and further testing to refine predictions.

PINN↗
DOE OSTI2026

Electric-vehicle battery second-life and recycling pathways: How economics depend on chemistry, processing, and application

We assess the economics of repurposing and recycling electric vehicle (EV) batteries by estimating the maximum acquisition price repurposers and recyclers could pay for used EV packs across cathode chemistries, first-life conditions, second-life applications, and recycling processes. We develop a novel open-source process-based cost model of a UL-1974-certified repurposing facility and leverage battery degradation models to estimate the maximum acquisition price repurposers could pay for used EV batteries while producing second-life battery energy storage systems with life-adjusted costs equivalent to new systems. We compare these maximum price estimates to maximum prices for recyclers based on cost and revenue estimates from the EverBatt model. We find that repurposing is more economical than recycling for lithium iron phosphate (LFP) batteries, due to their relatively long life and low value materials; recycling is generally more economical than repurposing for lithium nickel cobalt aluminum oxide (NCA) batteries, due to their shorter life and higher value materials; and the economics for lithium nickel manganese cobalt oxide (NMC) batteries depend more heavily on first life retirement conditions and second life application intensity. These results suggest an overall strategy: reuse LFP, recycle NCA, and sort NMC into recycling or repurposing pathways based on state of health and second-life application.

25 ENERGY STORAGE↗
DOE OSTI2020

Real-Time Acoustic Analysis of Batteries

The project explored development and commercialization of an acoustical approach to battery diagnostics. The technology has significant potential impacts for battery manufacturing and quality assurance, battery management during operation, and could be an enabler for the second-life battery market. Research was focused on inspecting and analyzing the physical condition of batteries using ultrasound. This consisted of designing and building hardware for gathering high-quality acoustic data, as well as using battery charge-discharge cyclers and temperature chambers to operate and age the batteries. Over the course of the 2-year program, we were able to build our first prototypes that are robust enough to be used by industry partners to evaluate our technology. Using the same prototypes, we also showed preliminary evidence that our acoustic inspection method may have distinct advantages over standard electrical methods in terms of detecting differences in the physical quality of battery cells. The project also expanded the participant’s core capabilities beyond time-of-flight acoustic measurements.

25 ENERGY STORAGE↗
DOE OSTI2020

Development of the Intelligent, Preventive Infrared (IR) Inspection System Housed in Hybrid Robotic Platforms

Robots and robotic systems that are designed for inspection, environmental study, and health and safety aid are becoming an increasing necessity. However, there is a number of challenges that accompany robots that are designed for these specific applications. These challenges include: navigating compact, enclosed spaces, travelling over multiple terrains and large obstacles, using the proper sensing and detection methods to assess an environment, and the use of lightweight and durable materials. The robotic platforms currently in development look at all of these challenges and attempt to overcome them. These designs specific use of hybrid robotic platforms, or platform that utilizes soft and rigid materials, allows for a more flexible platform and makes environments more navigable. To further improve the navigation of the platforms and environmental assessment, a novel infrared detection system is housed in the platforms to create a robot that can be used for the applications listed above and more. Objectives: Further develop two types of robotic platforms that utilize additive manufacturing, soft materials, and rigid materials. Continue the development of an intelligent and inhibitory infrared detection system based on an artificial intelligence (AI) algorithm. Continued study and fabrication of active soft materials designed for both sensing and actuation in hybrid robotic systems. Improve additive manufacturing fabrication to design rigid and semi-rigid components for hybrid robotic platforms. Transformable Wheel Robotic Platform: The chassis, wheels, tires and inspection system housing use different additive manufacturing techniques for fabrication. Continued work with additive manufacturing has lead to studies in metal-based printing and modular design and manufacturing. The new platform design with integrated electrical component printed. This will allow integration of the sensor housing onto the platform. Electrical components are being tested for battery life and performance. To improve this performance, such as integration of Lithium Polymer (LiPo) batteries. Snake Robotic Platform: The main focus of the development has centered around liquid-based soft actuators. That act on the principles of electrostatic and hydraulic actuation. A liquid dielectric sits between two compliant electrodes, contained by a flexible polymer shell. The electrodes and film gradually collapse toward each other from one corner of the electrode to the other. When the electrodes and film close together, a majority of the fluid is pushed into the area not covered by an electrode. A thin layer of the liquid dielectric remains between the electrode. The actuators will be stacked to cause large displacement, and move the linkages. The chassis of this platform uses purely additively manufactured linkages. Intelligent, Preventive IR Inspection System: Development of the AI for the system has lead to using a Scikit-Learn which assists in creating predictive models based on Regression, clustering, classification etc. To improve the infrared thermometry for low emissivity sources, work on the fabrication of a tandem photoconductive infrared thermometer was a main focus. Distance-Voltage-Temperature response data has been collected in the range of 7 cm - 100 cm and 200-400 deg. C. Modifications were made to the existing test bench to have a better control over the data. Automated data collection was realized using a Python code and an Arduino controlled stepper motor to increase the sample rate. A protective enclosure has been built around the setup to minimize the effect of the environment on the measurements. To better predict temperature, different AI models are being optimized. The regression model, LARS showed a high accuracy but had convergence issues and only works for the current test set-up. Results: The Transformable Wheel Robot has developed into a more flexible and modular platform. With the improvements to the current work, effort on the tire or soft gripper design been a large focus. The soft grippers will be interchange able to allow for increased performance in identified terrain types. The development of the liquid-based actuators allows the snake robotic platform to achieve the goals of being flexible and able to navigate confined spaces. However, there is room for improvement. Optimization work is currently being done in COMSOL Multiphysics. With the current IR system set-up the LARS model perfectly predicts the data; however, considering the mobility aspect of the project other models will allow for an optimized system. Testing of other model types is currently being done.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
NASA NTRS1995

Progress towards computer simulation of NiH2 battery performance over life

The long-term performance of rechargeable battery cells has traditionally been verified through life-testing, a procedure that generally requires significant commitments of funding and test resources. In the situation of nickel hydrogen battery cells, which have the capability of providing extremely long cycle life, the time and cost required to conduct even accelerated testing has become a serious impediment to transitioning technology improvements into spacecraft applications. The utilization of computer simulations to indicate the changes in performance to be expected in response to design or operating changes in nickel hydrogen cells is therefore a particularly attractive tool in advanced battery development, as well as for verifying performance in different applications. Computer-based simulations of the long-term performance of rechargeable battery cells have typically had very limited success in the past. There are a number of reasons for the lack in progress in this area. First, and probably most important, all battery cells are relatively complex electrochemical systems, in which performance is dictated by a large number of interacting physical and chemical processes. While the complexity alone is a significant part of the problem, in many instances the fundamental chemical and physical processes underlying long-term degradation and its effects on performance have not even been understood. Second, while specific chemical and physical changes within cell components have been associated with degradation, there has been no generalized simulation architecture that enables the chemical and physical structure (and changes therein) to be translated into cell performance. For the nickel hydrogen battery cell, our knowledge of the underlying reactions that control the performance of this cell has progressed to where it clearly is possible to model them. The recent development of a relative generalized cell modelling approach provides the framework for translating the chemical and physical structure of the components inside a cell into its performance characteristics over its entire cycle life. This report describes our approach to this task in terms of defining those processes deemed critical in controlling performance over life, and the model architecture required to translate the fundamental cell processes into performance profiles.

Zimmerman, Albert H.↗
DOE OSTI2022

An analytical method for identifying synergies between behind-the-meter battery and thermal energy storage

Electric utilities build generation capacity to meet the highest demand period, and they often pass on the costs associated with these peaking generators to building owners through demand charges. Building owners can minimize these demand charges by shifting energy use away from peak periods with behind-the-meter storage. This storage can include batteries, which can directly shift the metered load, or thermal energy storage, which can shift thermal-driven electric loads like air conditioning. However, there is a lack of research on how best to combine battery and thermal energy storage. In this study, we develop an analytical sizing method to calculate the potential demand reduction and annualized cost savings for different combinations of thermal and battery energy storage sizes. We show that adding batteries to a thermal energy storage system can increase the total system's load shaving potential. This is particularly true when the building has onsite photovoltaic generation or electric vehicle charging, which add significant variability to the load shape. We also show that for a given total storage size, selecting a higher fraction of thermal energy storage can significantly lower the cycling of the battery, and therefore extend the battery life. This, combined with the expected lower first cost of thermal energy storage materials compared to batteries, shows that hybrid energy storage systems can outperform a standalone battery or standalone thermal storage system. Assuming the thermal storage has a capital cost 6x lower than the battery, our analysis shows that the optimal system is 71% thermal energy storage and 29% battery energy storage for a scenario with electric vehicle charging. The annualized cost savings for this system are $48.6 k/yr, whereas an equivalently sized standalone thermal energy storage system would provide annualized cost savings of $28.5 k/yr and a standalone battery would lead to savings of $8.72 k/yr. The hybrid system also reduces battery cycling by 52% compared to a standalone battery, extending battery lifetime.

25 ENERGY STORAGE↗
DOE OSTI2021

Case Study of Recycling of Low Cobalt Batteries, OnTo Technology and King County Transit

Lithium-ion recycling is challenged by cost and safety related to low value elements and battery reactivity. OnTo is the first to demonstrate and develop technologies that address these challenges. Battery deactivation eliminates hazards and enables a roadmap for safe, low-cost end-of-life battery services essential to the industry. Deactivation coupled with Cathode-healing provides safety and efficiency in material recycling that can be applied all along the manufacturing value chain and for numerous chemistries in the market. Dr. Sloop will present recent developments in application and scale of these innovative technologies.

25 ENERGY STORAGE↗
DOE OSTI2021

Battery asset management with cycle life prognosis

We report Battery Asset Management problem determines the minimum cost replacement schedules for each individual asset in a group of battery assets that operate in parallel. Battery cycle life varies under different operating conditions including temperature, depth of discharge (DOD), charge rate, etc., and a battery deteriorates due to usage, which cannot be handled by current asset management models. This paper presents a new battery asset management methodology where battery cycle life prognosis is integrated with parallel asset management to reduce lifecycle cost of the Battery Energy Storage Systems (BESS). For the battery failure time prognosis, a nonlinear physics-based battery capacity fade model is developed and incorporated in parallel asset management model to update battery capacity over time. Experiment results have shown that the developed battery asset management methodology can be conveniently used to facilitate BESS asset management decision making thereby decreasing asset lifecycle costs.

25 ENERGY STORAGE↗