金属氢化物复合式高压储氢器的研究

为提高高压储氢容器的体积储氢密度,采用具有高体积储氢密度的储氢合金与轻质高压容器复合组成高压金属氢化物复合式储氢器.为获得高压氢源,研究了Mm-Ml-Ni-Al(Mm为富铈混合稀土,Ml为富镧混合稀土)的储氢特性,并试制了化学热压缩器.采用研制的高压氢源,对具有高吸放氢平台压力的Ce-Ni系合金的高压储氢特性进行了研究.实验结果表明:以Ml或Ca部分取代Mm以及Al对Ni的部分置换后合金活化性能和吸放氢压力滞后明显改善,(Mm-Ml)0.8Ca0.2(Ni-Al)多元合金具有较好的储氢性能,适合于作为化学热压缩合金.CeNi5基多元合金在40MPa氢压条件下,合金具有较好的活化性能和吸放氢动力学性能,合金最大储氢容量分别达到1.6wt%.将优化的储氢合金与自制的轻质高压储氢容器复合组成的金属氢化物复合式高压储氢器,当储氢合金的填充量达到0.2(体积分数)时,其体积储氢密度提高50%.     

小型PEMFC电源系统热设计实验研究

通过实验研究了利用燃料电池产生的废热以强制对流传热的方式给金属氢化物储氢器加热的可行性与具体的设计方案,与目前已报道的国内外便携式PEMFC系统相比,该方案无任何附属设备,使系统保持较高的整体效率,提高了金属氢化物储氢器的放氢性能.通过正交实验和实验数据的方差分析得知该方案在保证金属氢化物储氢器持续放氢的同时,对PEMFC无明显负面影响.     

氢存储技术

日益严峻的能源危机和环境污染，使得发展清洁的可再生能源成为各个国家的重要议题。氢能源以其可再生性和良好的环保效应成为未来最具发展潜力的能源载体。氢的储存是发展氢能技术的难点之一。文章介绍了高压、液化、金属氢化物和碳质吸附等储氢技术的研究现状，并对储氢技术的发展趋势进行了讨论。     

Hydrogen storage technology: Current status and prospects

储氢技术作为氢气生产与使用之间的桥梁,至关重要。本文综述了目前常用的储氢技术,主要包括物理储氢、化学储氢与其它储氢。物理储氢主要包括高压气态储氢与低温液化储氢,具有低成本、易放氢、氢气浓度高等特点,但安全性较低。化学储氢包括有机液体储氢、液氨储氢、配位氢化物储氢、无机物储氢与甲醇储氢。其虽保证了安全性,但其放氢难,且易发生副反应,氢气浓度较低。其它储氢技术包括吸附储氢与水合物法储氢。吸附储氢技术的储氢效率受吸附剂的影响较大,且不同程度的存在放氢难、成本高、储氢密度不高等问题。水合物法储氢具有易脱氢、成本低、能耗低等特点,但其储氢密度较低。在此基础上,本文基于现状分析,简要展望了储氢技术今后的研究方向。     

潜艇燃料电池AIP氢燃料活性炭低温吸附储存

设计利用潜艇液氧冷量的燃料电池(FC)-AIP活性炭低温吸附储氢系统,在模拟潜艇航行中晃动和振动的平台上,测试氢在活性炭上的吸附等温线和储氢系统在为质子交换膜燃料电池(PEMFC)供气时的特性。结果表明,吸附等温线受平台晃振的影响小;温度为113K、压力为6MPa时,比表面积为1450m2.g-1的SAC-02活性炭储氢系统的质量储氢密度可超过当前艇用储氢合金的质量储氢密度;在2kW PEMFC电堆典型工况所需的氢气量(质量流率21.44L.min-1)下,通过充气过程的液氧预冷和放气过程的循环介质加热,可使储罐中心和壁面在整个过程中的最大温差小于5℃。活性炭低温吸附储氢系统的质量密度和储放氢特性能满足艇用FC-AIP系统的要求。     

氢——未来的绿色燃料

石油燃料在几十年内逐渐耗尽,而燃料电池以其高效、清洁的特点将会成为未来交通的推动力.本文对可再生绿色能源载体--氢的研制方法进行了研究,详细阐述了两种制氢的工艺过程--热化学工艺和电解水工艺过程.给出了氢气的四种储存方法,其中金属氢化物和碳质吸附储氢两种方法,由于安全可靠,储存效率较高,是目前广泛研究的储氢方式.本文综述了氢能系统的各项技术,并对未来的发展趋势作了展望.     

苯、甲苯电催化加氢研究进展

该文总结了有机液态氢化物－苯、甲苯电催化加氢研究的进展情况，并从理论和试验研究两方面给以介绍。苯，甲苯作为液态有机储氢介质，具有储量大[其最大储氢量分别为7．14％和6．19（均为质量百分数）]，易于输运（与汽油输运类似）及加氢－脱氢可逆性好的特点（可反复循环，稳定可达－20a)，是一类具有潜在应用前景的新型储氢材料。电催化加氢可在温和的条件下进行，具有很好的应用前景。     

燃料电池混合动力机车供氢系统安全管理研究

简要介绍了氢气的多种存储方式以及储氢的现状,并对多种储氢方式进行了比较分析,讨论了氢气应用在燃料电池混合动力机车上的可行性。结合目前混合动力机车加氢装置安全保护要求,提出了几种可用的安全保护技术和措施。重点对车载加氢装置的安全管理做了介绍并展开了有益的探讨,为燃料电池混合动力机车加氢装置的研发和安全稳定工作提供了理论参考。     

浅谈高压储氢压力容器材料选用

高压储氢容器作为现今主流高压气态储氢方式常用的压力容器,长期在高压临氢工况下运行,本文从储氢容器的使用条件、材料性能、制造工艺、经济合理性和标准规范要求等方面介绍了高压储氢压力容器材料选用.     

碳质吸附剂吸附储氢的研究现状

论述了活性炭、碳纳米纤维、碳纳米管吸附储氢的研究历程，从实验、理论研究两个方面总结了前人的研究成果：活性炭在低温下有好的吸附储氢特性，但在室温条件下的结果却不令人满意；碳纳米管和碳纳米纤维的实验结果令人振奋，但众多的实验结果并不一致；碳纳米材料的制备技术和净化技术还仅处在实验规模的阶段；蒙特卡罗、密度泛函等方法是常用的计算机模拟技术，但目前它们只是考虑了理想的物理模型，没有考虑碳纳米管表面的一些不规则现象；碳质吸附剂吸附储氢从理论到应用还有一段距离。     

Recent challenges of hydrogen storage technologies for fuel cell vehicles

Fuel cell vehicles have a high potential to reduce both energy consumption and carbon dioxide emissions. However, due to the low density, hydrogen gas limits the amount of hydrogen stored on board. This restriction also prevents wide penetration of fuel cells. Hydrogen storage is the key technology towards the hydrogen society. Currently high-pressure tanks and liquid hydrogen tanks are used for road tests, but both technologies do not meet all the requirements of future fuel cell vehicles. This paper briefly explains the current status of conventional technologies (simple containment) such as high-pressure tank systems and cryogenic storage. Another method, hydrogen-absorbing alloy has been long investigated but it has several difficulties for the vehicle applications such as low temperature discharge characteristics and quick charge capability due to its reaction heat. We tested a new idea of combining metal hydride and high pressure. It will solve some difficulties and improve performance such as gravimetric density. This paper describes the latest material and system development.     

Affordable hydrogen supply pathways for fuel cell vehicles

Fuel cell vehicles can be powered directly by hydrogen stored on the vehicle, or indirectly by extracting hydrogen from onboard liquid fuels such as methanol or gasoline. The direct hydrogen fuel cell vehicle is preferred, since it would be less complex, have better fuel economy, lower greenhouse gas emissions, greater oil import reductions and would lead to a sustainable transportation system once renewable energy was used to produce hydrogen. The two oft-cited concerns with direct hydrogen fuel cell vehicles are onboard hydrogen storage and the lack of hydrogen supply options. Directed Technologies, Inc., working with the Ford Motor Company under a Department of Energy cost shared contract to develop direct hydrogen fuel cell vehicles, has addressed both perceived roadblocks to direct hydrogen fuel cell vehicles. We describe realistic, cost effective options for both onboard hydrogen storage and for economically viable hydrogen infrastructure development.     

Thermal design analysis of a 1 L cryogenic liquid hydrogen tank for an unmanned aerial vehicle

Thermal design analysis of a 1-L cryogenic liquid hydrogen storage tank without vacuum insulation for a small unmanned aerial vehicle was carried out in the present study. To prevent excess boil-off of cryogenic liquid hydrogen, the storage tank consisted of a 1-L inner vessel, an outer vessel, insulation layers and a vapor-cooled shield. For a cryogenic storage tank considered in this study, the appropriate heat inleak was allowed to supply the boil-off gas hydrogen to a proton electrolyte membrane fuel cell as fuel. In an effort to accommodate the hydrogen mass flow rate required by the fuel cell and to minimize the storage tank volume, a thermal analysis for various insulation materials was implemented here and their insulation performances were compared. The present thermal analysis showed that the Aerogel thermal insulations provided outstanding performance at the non-vacuum atmospheric pressure condition. With the Aerogel insulation, the tank volume for storing 1-L liquid hydrogen at 20 K could be designed within a storage tank volume of 7.2 L. In addition, it was noted that the exhaust temperature of boil-off hydrogen gas was mainly affected by the location of a vapor-cooled shield as well as thermal conductivity of insulation materials.     

Vehicular storage of hydrogen in insulated pressure vessels

This paper describes an alternative technology for storing hydrogen fuel onboard vehicles. Insulated pressure vessels are cryogenic capable vessels that can accept cryogenic liquid hydrogen, cryogenic compressed gas or compressed hydrogen gas at ambient temperature. Insulated pressure vessels offer advantages over conventional storage approaches. Insulated pressure vessels are more compact and require less carbon fiber than compressed hydrogen vessels. They have lower evaporative losses than liquid hydrogen tanks, and are lighter than metal hydrides.

The paper outlines the advantages of insulated pressure vessels and describes the experimental and analytical work conducted to verify that insulated pressure vessels can be safely used for vehicular hydrogen storage. Insulated pressure vessels have successfully completed a series of certification tests. A series of tests have been selected as a starting point toward developing a certification procedure. An insulated pressure vessel has been installed in a hydrogen fueled truck and tested over a six month period.     

Safe,long range,inexpensive and rapidly refuelable hydrogen vehicles with cryogenic pressure vessels

Hydrogen storage is often cited as the greatest obstacle to achieving a hydrogen economy free of environmental pollution and dependence on foreign oil. A compact high-pressure cryogenic storage system has promising features to the storage challenge associated with hydrogen-powered vehicles. Cryogenic pressure vessels consist of an inner vessel designed for high pressure (350 bar) insulated with reflective sheets of metalized plastic and enclosed within an outer metallic vacuum jacket. When filled with pressurized liquid hydrogen, cryogenic pressure vessels become the most compact form of hydrogen storage available. A recent prototype is the only automotive hydrogen vessel meeting both Department of Energy's 2017 weight and volume targets. When installed onboard an experimental vehicle, a cryogenic pressure vessel demonstrated the longest driving distance with a single H₂ tank (1050 km). In a subsequent experiment, the vessel demonstrated unprecedented thermal endurance: 8 days parking with no evaporative losses, extending to a month if the vehicle is driven as little as 8 km per day. Calculations indicate that cryogenic vessels offer compelling safety advantages and the lowest total ownership cost of hydrogen storage technologies. Long-term (∼10 years) vacuum stability (necessary for high performance thermal insulation) is the key outstanding technical challenge. Testing continues to establish technical feasibility and safety.     

欧美发展氢能和燃料电池汽车的举措及对我国的建议

目前发达国家都在加快对新型车用能源和车辆技术的研发。氢能和燃料电池技术被一些发达国家视为未来道路交通能源的理想解决方案,并投入巨资开展研发活动。目前欧美等国已经形成政府支持下的多方联合开发、推广氢能和燃料电池汽车技术的模式,企业之间也建立起优势互补、强强联合的合作伙伴关系。重点介绍了在欧洲氢能和燃料电池技术领域处于领先地位的德国的主要做法及取得的进展。我国氢能和燃料电池汽车技术的研发、示范和推广工作起步时间不长．国外先进国家的经验和做法值得借鉴。最后为我国发展氢能和燃料电池汽车提出了建议。     

Refuelling scenarios of a light urban fuel cell vehicle with metal hydride hydrogen storage. Comparison with compressed hydrogen storage counterpart

The high price of hydrogen fuel in the fuel cell vehicle refuelling market is highly dependent on the one hand from the production costs of hydrogen and on the other from the capital cost of a hydrogen refuelling station's components to support a safe and adequate refuelling process of contemporary fuel cell vehicles. The hydrogen storage technology dominated in the vehicle sector is currently based on high-pressure compressed hydrogen tanks to extend as much as possible the driving range of the vehicles. However, this technology mandates the use of large hydrogen compression and cooling systems as part of the refuelling infrastructure that consequently increase the final cost of the fuel. This study investigated the prospects of lowering the refuelling cost of small urban hydrogen vehicles through the utilisation of metal hydride hydrogen storage. The results showed that for low compression hydrogen storage, metal hydride storage is in favour in terms of the dispensed hydrogen fuel price, while its weight is highly comparable to the one of a compressed hydrogen tank. The final refuelling cost from the consumer's perspective however was found to be higher than the compressed gas due to the increased hydrogen quantity required to be stored in fully empty metal hydride tanks to meet the same demand.     

Operating experience with a liquid-hydrogen fueled buick and refueling system

An investigation of liquid-hydrogen storage and refueling systems for vehicular applications was made in a recently completed project. The vehicle used in the project was a 1979 Buick Century sedan with a 3.8.1, displacement turbocharged V6 engine and an automatic transmission. The vehicle had a fuel economy for driving in the high altitude Los Alamos area that was equivalent to 2.4 km/l of liquid hydrogen or 8.9 km/l of gasoline on an equivalent energy basis. About 22% less energy was required using hydrogen rather than gasoline to go a given distance based on the Environmental Protection Agency estimate of 7.2 km/l of gasoline for this vehicle. At the end of the project the engine had been operated for 138 h and the car driven 3633 km during the 17 months that the vehicle was operated on hydrogen. Two types of onboard liquid-hydrogen storage tanks were tested in the vehicle; the first was an aluminium Dewar with a liquid-hydrogen capacity of 1101.; the second was a Dewar with an aluminium outer vessel, two copper vapor-cooled thermal radiation shields, and a stainless steel inner vessel with a liquid-hydrogen capacity of 1551. The Buick had an unrefueled range of about 274 km with the first liquid-hydrogen tank and about 362 km with the second. The Buick was fueled at least 65 times involving a minimum of 8.1 kl of liquid hydrogen using various liquid-hydrogen storage Dewars at Los Alamos and a semiautomatic refueling station. A refueling time of 9 min was achieved, and liquid-hydrogen losses during refueling were measured. The project has demonstrated that liquid-hydrogen storage onboard a vehicle, and its refueling, can be accomplished over an extended period without any major difficulties; nevertheless, appropriate testing is still needed to quantitatively address the question of safety for liquid-hydrogen storage onboard a vehicle.