Fuel Cell Range Extender Research Articles

Better integrating battery and fuel cells in electric vehicles

AbstractThis paper presents an innovative approach to enhancing the range of battery electric vehicles (BEVs) through the integration of a hydrogen fuel cell range extender. By combining the high energy efficiency of BEVs with the rapid refueling capability and extended range of hydrogen fuel cells, this hybrid system addresses the limitations of current electric vehicles in scenarios demanding longer driving ranges or quicker refueling options. Our study encompasses both experimental and theoretical analyses, leading to the proposal of a BEV configuration that includes a smaller battery complemented by a fuel cell range extender. The conventional fuel cell electric vehicle (FCV) examined relies exclusively on hydrogen fuel and features a minimal battery without plug‐in functionality, resulting in suboptimal energy economy. In contrast, our proposed BEV with a fuel cell range extender employs a larger battery capacity of 12 to 16 kWh alongside a downsized fuel cell stack and reduced hydrogen tank size. This configuration significantly improves energy recovery during braking and extends electric operation, thereby doubling the vehicle's energy economy. The proposed system not only enhances energy efficiency but also reduces the weight and volume of the overall energy storage system. Preliminary estimates suggest that the miles‐per‐gallon equivalent (MPGe) of this hybrid solution could exceed 140 over the US EPA certification cycle, outperforming existing PHEVs, BEVs, and FCVs.

Low demand solution for (sub)urban personal transport by a direct hybrid (fuel cell-supercapacitors) source

For urban or suburban transport, the power demand of a personal car does not exceed 30 kW/ton, far below the power offered by regular cars designed for any ride. Moreover, it was formerly shown that the above power could be attained by a 10 kW fuel cell directly hybridized to a supercapacitor string able to deliver a 20 kW power peak. This theoretical fact, corresponding to low resource demand in the car manufacturing, was validated up to ½ scale on the bench. Within a research project in University of Lorraine, the target is to validate the low-resource demanding concept in a real hydrogen electric vehicle (fuel cell range extender Renault Kangoo) and to examine related aspects by combining engineering sciences to social and human sciences and economics. After reminding the former validation on a bench, the paper describes current work on how the electrical power is managed in the Renault H2 ZE Kangoo, by characterization of the fuel cell and thorough analysis of the transients of electrical and non-electrical variables available in the vehicle in various rides. Besides, risks and life cycle analysis of a one-ton hybrid vehicle have been evaluated in comparison with other 30 kW vehicles powered by either a fuel cell, or batteries or an internal combustion engine. Finally, social acceptability of the fuel cell cars by regular citizens is presented, revealing a positive opinion at fuel cells and hydrogen, however with a moderate readiness to its acquisition.

A fuel cell range extender integrating with heat pump for cabin heat and power generation

Batteries, Heat Pumps (HPs), and fuel cells (FCs) are critical for transport decarbonization and a net zero future. However, cabin heating in extreme conditions leads to severe driving range reduction in current Electric Vehicles (EVs). The performance of the heat pump (HP) in EVs and its performance enhancement technologies are widely investigated but cannot, simultaneously, provide sufficient heat and high COP. The source and amount of the waste heat within a vehicle for the heat pump integrated system is a crucial challenge to improve performance. The structure becomes increasingly complicated, but the benefits are not significant. Therefore, in this study, a small Fuel Cell, battery and heat pump integrated energy management system for range extended EVs (FCBEEV) is designed. The cogeneration characteristic of the fuel cell and waste heat from battery pack are utilised by the heat pump to ensure a high-level of cabin comfort in extremely cold temperatures and an extension of the driving range. A numerical model was established in MATLAB and the results were analysed from energy, exergy, environment, and economic (4E) perspectives. In this study, we show that the highest COPsys of the proposed system is 5.8 and can improve the driving range (DR) by 65% to 110% compared to the reference systems. The exergy efficiency of the suggested system is 75% at −10 °C and the fuel cell and internal condenser are the primary causes of the exergy destruction. The environmental impact decreases by 13 kg/year per car compared to current EVs with a Positive Temperature Coefficient (PTC) and Air Source Heat Pump (ASHP) system, and the reduction is primarily sourced from the indirect emissions. The operating cost which includes driving and heating is 28.9% higher than cited for an ASHP and PTC system and 41% higher than the PTC baseline system. The payback duration is 300,000 km at current market prices, and it is predicted to be shorter to 100,000 km, if the cost of the fuel cell stack is estimated at £4000 and the H2 price is the same as electricity. We anticipate that the proposed system can significantly improve cabin comfort and driving range anxieties, as well as promote the decarbonization of transport.

Time and Energy Optimized Operating Strategies of a Digitally Connected Electric Vehicle with Fuel Cell Range Extender

Time and Energy Optimized Operating Strategies of a Digitally Connected Electric Vehicle with Fuel Cell Range Extender

Maximizing Driving Range for Fuel Cell Range Extender Vehicles With Fixed Energy Storage Costs

Industry and researchers are investigating both battery electric vehicles (BEVs) and fuel cell hybrid vehicles (FCHVs) for the future of sustainable passenger vehicle technology. While BEVs have clear efficiency advantages, FCHVs have key benefits in terms of refueling time and energy density. This article first proposes the concept of a fuel cell range extender vehicle (FCREV) that uses whole-day driving prediction (WDDP) control, which uses driver destination inputs to determine whether the planned driving trips that day will exceed the useable battery energy capacity. If so, the fuel cell is turned on at the start of the day. The benefit of WDDP control is that a smaller, lower cost fuel cell can be used to greatly extend the driving range since the fuel cell can charge the battery during both driving and parked periods of the day. Furthermore, this research proposes a fast analytical optimization algorithm for designing a WDDP-FCREV to maximize the range on a given drive cycle for a set cost. The results show that an optimized WDDP-FCREV can greatly exceed the range of the same-cost BEV, by 105%–150% for no H2 refueling and by 150%–250% when H2 refueling is allowed every 4 h.

Effect of dynamic and operational restrictions in the energy management strategy on fuel cell range extender electric vehicle performance and durability in driving conditions

Aiming at increasing fuel cell (FC) stack durability in driving conditions, part of the scientific community has focused its efforts on developing energy management strategies (EMS) for fuel cell hybrid vehicles (FCV). Nonetheless, most of these studies do not explicitly explain the effect of constraining the EMS in both degradation and performance when acting on the FC system dynamics or operational space nor consider the FC range-extender (FCREx) architecture for passenger car application. This study evaluates the potential of FCREx architecture to maximize FC stack durability and performance through control strategy dynamic and operational space limitations. For that purpose, a FCV modeling platform was developed and integrated together with an EMS optimizer algorithm and a semi-empirical advanced FC stack degradation model for driving cycle conditions. The resulting modeling platform was then simulated in WLTC 3b driving cycle to predict FC degradation and H2 consumption with different dynamic and operational restrictions. Practical limits for EMS constraining were identified as —di/dt—max = 0.001 A/cm2s or imin = 0.2 A/cm2 since they prevented the EMS from fulfilling the constant state-of-charge constraint in high-dynamic driving condition. In this sense, —di/dt—max = 0.01 A/cm2s and imin = 0.15 A/cm2 were recommended as the combination of constraints that maximizes FC stack durability (+110%) without affecting the FCV operability with only an increase in of 4.7% in H2 consumption. From these results, a set of recommendations and guidelines for FCREx vehicle manufacturers and FC stack developers were elaborated based on the benefits of understanding the dynamics and operational constraints that the FC system is going to be subjected to under real operation.

A modeling framework for predicting the effect of the operating conditions and component sizing on fuel cell degradation and performance for automotive applications

In this study, durability and performance prediction were integrated in the sizing process of the FC stack of a fuel cell range-extender (FCREx) vehicle together with the design of a dynamics-limited control strategy. For that purpose, a FCREx vehicle model integrating a FC stack, balance of plant, battery, H2 tank and vehicle body (C-class SUV) validated in previous studies was used. To predict FC stack degradation rate, a novel semi-empirical multi-layered degradation modeling framework for automotive application is proposed and developed. Degradation rates are calculated based on reference degradation rates measured at reference and known conditions (1st layer) and scaled with the electrochemical phenomena (2nd layer) and the operating conditions (3rd layer) through scaling functions based on physical tendencies. Results show how increasing the FC stack power decreases H2 consumption but increases durability, while increasing the dynamic limitations on the control strategy increases both H2 consumption and durability. The isolated effect of sizing implied a decrease in H2 consumption of ∼3% and an increase in FC stack durability of ∼53% when comparing the 40 kW and 100 kW designs. In contrast, the effect of dynamic limitations was significantly perceived in the 40 kW design which implied an increase in H2 consumption close to 8% and an increase in durability of 294% when comparing the infinite dynamics and the highest dynamically restricted cases. Nevertheless, the effect of sizing is neglected under high dynamic limitation and limiting the current density change rate to 0.001 A/cm2s may prevent the control strategy from fulfilling the charge sustaining mode in aggressive driving. Based on these results, a set of recommendations were elaborated for FC stack and FCV manufacturers aiming to apply FCREx architecture to passenger car vehicles.

Design and Modeling of Metallic Bipolar Plates for a Fuel Cell Range Extender

Fuel cells, designed for mobile applications, should feature compact and low-weight designs. This study describes a design process that fulfills the specific needs of target applications and the production process. The key challenge for this type of metallic bipolar plate is that the combination of two plates creates three flow fields, namely an anode side, a cathode side, and a coolant. This illustrates the fact that each cell constitutes an electrochemical converter with an integrated heat exchanger. The final arrangement is comprised of plates with parallel and separate serpentine channel configurations. The anode and cathode sides are optimized for operation under dry conditions. The final plate offers an almost perfect distribution of coolant flow over the active area. The high quality of this distribution is almost independent of the coolant mass flow, even if one of the six inlet channels is blocked. The software employed (OpenFOAM and SALOME) is freely available and can be used with templates.

Impact of fuel cell range extender powertrain design on greenhouse gases and NOX emissions in automotive applications

Fuel cell (FC) technologies for mobility are gaining interest as promising options to decarbonize the transport sector in line with the current progress towards the H2 economy. Previous studies show how the fuel cell range extender (FCREx) powertrain architecture can offer flexible and efficient operation along with the potentially low total cost of ownership (TCO) in passenger car applications. Cradle-to-grave emissions of these vehicles have not been estimated, nor their variation with the components sizing or the H2 production pathway analyzed. In this study, the life cycle assessment (LCA) and sizing methodologies were combined to address these knowledge gaps. The design spaces were generated by varying the FC maximum power, the battery capacity and the H2 tank capacity and by simulating the resulting designs with the WLTC 3b driving cycle. Then, the lifetime H2 and energy consumption results and design parameters were calculated and used as inputs to estimate the greenhouse gases (GHG) and NOX emissions on the manufacturing and fuel production cycles. From the results, it was proven how considering steam methane reforming (SMR) with carbon capture and storage (CCS) as the H2 production pathway could decrease by 60% and 38% GHG-100 and NOX emissions respectively, with respect to electrolysis where electricity is generated with the EU mix. The optimum design, in terms of emissions, was found to be with low-moderate battery capacity and moderate-high FC maximum power in contrast to the optimum design for performance, which had high battery capacity and high FC stack power.

Evaluation of Hybrid, Electric and Fuel Cell Powertrain Solutions for Class 6-7 Medium Heavy-Duty Vehicles

<div class="section abstract"><div class="htmlview paragraph">Electrification of heavy-duty trucks has received significant attention in the past year as a result of future regulations in some states. For example, California will require a certain percentage of tractor trailers, delivery trucks and vans sold to be zero emission by 2035. However, the relatively low energy density of batteries in comparison to diesel fuel, as well as the operating profiles of heavy-duty trucks, make the application of electrified powertrain in these applications more challenging. Heavy-duty vehicles can be broadly classified into two main categories; long-haul tractors and vocational vehicles. Long-haul tractors offer limited benefit from electrification due to the majority of operation occurring at constant cruise speeds, long range requirements and the high efficiency provided by the diesel engine. However, vocational applications can realize a significant benefit from electrified powertrains due to their lower vehicle speeds, frequent start-stop driving and shorter operating range requirements.</div><div class="htmlview paragraph">As the heavy-duty industry deals with solving challenges around the application of electrified powertrains, there are multiple pathways that can be explored to meet future regulatory requirements. This paper is the second part of a two-paper series that focuses on evaluating electrified solutions for Class 6-7 medium heavy-duty vehicles in the 2027 and beyond time frame. Using a model-based approach, this paper presents a comprehensive analysis that compares the baseline diesel powertrain against multiple alternative powertrain configurations. These configurations include, an optimized parallel diesel hybrid, all-electric, diesel range extender, gasoline range extender, Compressed Natural Gas (CNG) range extender, and fuel cell range extender; which are evaluated on the basis of cost of ownership, fuel efficiency, emissions, payback period, lost payload opportunity, range, and battery life. The analysis shows that for a near-term less-disruptive scenario wherein the conventional diesel powertrain layout is preserved, a 48V P3 parallel hybrid vehicle configuration is the most cost-effective solution, while for a near-term more-disruptive scenario, the Internal Combustion Engine (ICE) based Range Extender Electric Vehicles (REEVs) have the most potential to reduce greenhouse gas emissions while achieving lower cost of ownership than the baseline vehicle. For a longer-term and more-disruptive scenario, the all-electric vehicle configuration can achieve parity with the baseline vehicle cost of ownership provided the vehicle driving range requirement is limited to 100-150 miles. The analysis further highlights that the overall benefit of an all-electric powertrain solution depends significantly on the future battery technology advancements and vehicle range requirements.</div></div>

Optimization and sizing of a fuel cell range extender vehicle for passenger car applications in driving cycle conditions

Aiming to reduce global warming and emissions in general, cleaner technologies are the spotlight of research and industry development. Among them, fuel cell vehicles (FCV) are gaining interest to decarbonize the transport sector. Plug-in FCV or FCV in range-extender configuration (FCREx) is an interesting option to reduce the total cost of ownership (TCO) and the energy usage per km. The aim of this study was to generate design spaces of FCREx by varying the FC stack maximum power output, the battery capacity, and the H2 tank capacity to understand the implications of this architecture in range, consumption, and cost (estimated with a WLTP driving cycle). Unlike other studies, the approach was focused on a novel architecture for passenger vehicles and was focused on the development of the validated FC system model and the energy management strategy (EMS) optimization for each design, based on the Pontryagin Minimum Principle (PMP). Consumption was found to decrease with increasing battery capacity and FC maximum power due to the higher efficiency of the systems. The design spaces showed how with 5 kg of H2 and ≥50 kWh of battery capacity the maximum range of FCREx could be over 700 km. The results of this study showed how FCREx architecture could provide overall energy consumption saving up to 6.8% and H2 consumption saving ranging from 16.8% to 25%, compared to current commercial FCVs. The optimum FCREx design, not only based on performance, should have ∼30 kWh of battery capacity and ≥80 kW of FC maximum power to minimize manufacturing costs while maximizing efficiency.

Flexible 4-in-1 microsensor for in-situ diagnosis of electric motorcycle fuel cell range extender

The performance and life proton exchange membrane fuel cell (PEMFC) depend on local distribution of internal temperature, voltage, current and humidity, while its overall performance and life of PEMFC stack are directly affected different external operating conditions. However, the nonuniform distribution of temperature, voltage, current and humidity can occur anywhere in a PEMFC stack. In order to solve this problem, this study developed a real-time microscopic diagnosis technology for PEMFC stack performance. It applied the micro-electro-mechanical systems (MEMS) technology to build, a flexible 4-in-1 (temperature, voltage, current and humidity) microsensor, which can measure the four main physical properties inside the PEMFC stack, so as to determine the optimum operating conditions. The flexible 4-in-1 microsensor developed in this study was successfully applied to the interior of a motorcycle fuel cell range extender, and detected that the physical properties in different parts of the PEMFC stack, especially on temperature. The measured data could be used to determine whether a thermal stress concentration has been generated inside the PEMFC stack, thus, the operating conditions could be changed accordingly to relieve the concentration. Moreover, the data of local voltage and current could also indicate the local reaction status and the relationship between the reaction rate and temperature and humidity. The proposed technology can help manufacturers to use the collected data to adjust the production parameters, thereby accelerating fuel cell development, and extending cell performance and life.

Air mass flow and pressure optimisation of a PEM fuel cell range extender system

In order to eliminate the local CO2 emissions from vehicles and to combat the associated climate change, the classic internal combustion engine can be replaced by an electric motor. The two most advantageous variants for the necessary electrical energy storage in the vehicle are currently the purely electrochemical storage in batteries and the chemical storage in hydrogen with subsequent conversion into electrical energy by means of a fuel cell stack. The two variants can also be combined in a battery electric vehicle with a fuel cell range extender, so that the vehicle can be refuelled either purely electrically or using hydrogen. The air compressor, a key component of a PEM fuel cell system, can be operated at different air excess and pressure ratios, which influence the stack as well as the system efficiency. To asses the steady state behaviour of a PEM fuel cell range extender system, a system test bench utilising a commercially available 30 kW stack (96 cells, 409 cm2 cell area) was developed. The influences of the operating parameters (air excess ratio 1.3 to 1.7, stack temperature 20 °C–60 °C, air compressor pressure ratio up to 1.67, load point 122 mA/cm2 to 978 mA/cm2) on the fuel cell stack voltage level (constant ambient relative humidity of 45%) and the corresponding system efficiency were measured by utilising current, voltage, mass flow, temperature and pressure sensors. A fuel cell stack model was presented, which correlates closely with the experimental data (0.861% relative error). The air supply components were modelled utilising a surface fit. Subsequently, the system efficiency of the validated model was optimised by varying the air mass flow and air pressure. It is shown that higher air pressures and lower air excess ratios increase the system efficiency at high loads. The maximum achieved system efficiency is 55.21% at the lowest continuous load point and 43.74% at the highest continuous load point. Future work can utilise the test bench or the validated model for component design studies to further improve the system efficiency.

The Current Status of Hydrogen and Fuel Cell Development in China

Abstract Potentially large amount of hydrogen resource in China could theoretically supply 100 × 106 fuel cell passenger cars yearly. The Chinese government highly values the hydrogen and fuel cell technology. Policies and plans have been put forward densely in the recent five years. Numerous companies, research institutes, and universities are developing proton exchange membrane fuel cell (PEMFC) and solid oxide fuel cell (SOFC)-related technologies. A preliminary local supplier chain of fuel cell-related technology has been formed. However, the lifetime is still a key issue for the fuel cell technology. More than 3500 fuel cell range extender electric vehicles were manufactured during 2016 and 2018, and at the beginning of 2019, there have been more than 40 hydrogen refueling stations including both under operation and under construction. It is estimated the number of fuel cell-based electric vehicles will reach 36,000 by the end of 2020; therefore, lack of hydrogen refueling station has become a key restriction for development of the fuel cell vehicle industry.

Real-Time Energy Management Strategy for Fuel Cell Range Extender Vehicles Based on Nonlinear Control

Energy management strategy (EMS) is very crucial for the hybrid power system of fuel cell range extender vehicles (FCREV) with respect to improving vehicle energy consumption economy. The objective of this article is to formulate a real-time EMS to efficiently regulate the energy flow of the hybrid power system under complex driving conditions. First, a nonlinear control system is developed to calculate the reference output current of the proton exchange membrane FC for energy management, and the theoretical stability of the nonlinear control system is proven by using the Lyapunov function. Then, a physics-based model of FCREVs is established in the Simulink environment, which considers the energy losses from the braking and the mechanical transmission system. Finally, fuzzy logic control is proposed as a benchmark to compare the performance of the proposed EMS in a combined driving cycle testing condition. The simulation results show that the proposed EMS has the potential for prolonging the lifespan of FC and achieves optimal energy consumption efficiency of FC, as well as improving the energy consumption economy of FCREVs.

EXPERIENCE OF AVL AND NISSAN COMPANIES IN APPLICATION OF SOFC POWER PLANTS AS RANGE EXTENDERS FOR ELECTRIC LIGHT VEHICLES

In previous manuscripts we considered perspective of application of power plants based on solid oxide fuel cells (SOFC) as auxiliary power units for heavy truck automobile transport: we considered USA and European experience. High level of this technology promises was shown with description of economical and technical data. In current paper we consider the first world experience of SOFC power plant application as a range extender for electrical cars. This project was implemented by consortium of Austrian company «AVL» and «Nissan». Described light vehicle was developed and constructed to be demonstrated during summer Olympic games in 2016 in Rio (Brazil). Bio-ethanol manufactured from natural sources was used as a fuel for solid oxide fuel cell power plant. Constructed vehicle was equipped with lithium-ion battery pack as primary power source, solid oxide fuel cell power plant with power output of 5 kW was used as range extender to enlarge the range of vehicle in a way of battery recharge during operation and discharge due to road motion. This light vehicle was tested in road conditions. Range of trip using only lithium-ion battery pack was measured on a level of 120 km, introduction of solid oxide fuel cell power plant gave opportunity to extend this value up to about 600 km – in 5 times. Startup time of SOFC power plant described in this work was showed on level of about 40 min which is good enough for this application as solid oxide fuel cell power plant is not a primary power source and vehicle can start motion before start of SOFC system using batteries energy. These data obviously show high advantages of introduction of such system of battery pack with solid oxide fuel cell range extender in light vehicles. Keywords: automobile transport; car; solid oxide fuel cells; SOFC; power plant; range extender; electrical car.

Intelligent Hydrogen Fuel Cell Range Extender for Battery Electric Vehicles

Road transport is recognized as having a negative impact on the environment. Policy has focused on replacement of the internal combustion engine (ICE) with less polluting forms of technology, including battery electric and fuel cell electric powertrains. However, progress is slow and both battery and fuel cell based vehicles face considerable commercialization challenges. To understand these challenges, a review of current electric battery and fuel cell electric technologies is presented. Based on this review, this paper proposes a battery electric vehicle (BEV) where components are sized to take into account the majority of user requirements, with the remainder catered for by a trailer-based demountable intelligent fuel cell range extender. The proposed design can extend the range by more than 50% for small BEVs and 25% for large BEVs (the extended range of vehicles over 250 miles), reducing cost and increasing efficiency for the BEV. It enables BEV manufacturers to design their vehicle battery for the most common journeys, decreases charging time to provide convenience and flexibility to the drivers. Adopting a rent and drop business model reduces the demand on the raw materials, bridging the gap in the amount of charging (refueling) stations, and extending the lifespan for the battery pack.

Loop Energy fuel cell range-extenders for California truck project

Canadian-based Loop Energy's heavy-duty fuel cell range-extender will power two hybrid-electric Class 8 drayage trucks that will operate for a year as part of a Fast Track Fuel Cell Truck Project in southern California, as a precursor to the wider deployment of zero-emission Class 8 drayage trucks.

Engie unveils largest hydrogen utility fleet, first alternative multi-fuel station in France

The first alternative multi-fuel station in France has been inaugurated at the Rungis International Market in Paris, and will serve a fleet of 50 Renault Kangoo ZE-H2 utility vehicles featuring hydrogen fuel cell range-extender systems. The overall project has been given financial support from the Fuel Cells and Hydrogen Joint Undertaking (FCH JU).

Multi-mode energy management strategy for fuel cell electric vehicles based on driving pattern identification using learning vector quantization neural network algorithm

The development of fuel cell electric vehicles can to a certain extent alleviate worldwide energy and environmental issues. While a single energy management strategy cannot meet the complex road conditions of an actual vehicle, this article proposes a multi-mode energy management strategy for electric vehicles with a fuel cell range extender based on driving condition recognition technology, which contains a patterns recognizer and a multi-mode energy management controller. This paper introduces a learning vector quantization (LVQ) neural network to design the driving patterns recognizer according to a vehicle's driving information. This multi-mode strategy can automatically switch to the genetic algorithm optimized thermostat strategy under specific driving conditions in the light of the differences in condition recognition results. Simulation experiments were carried out based on the model's validity verification using a dynamometer test bench. Simulation results show that the proposed strategy can obtain better economic performance than the single-mode thermostat strategy under dynamic driving conditions.