Electrochemical Impedance Analysis for Fuel Cell 2

toruhara

2023年12月11日 21:28

本文はこちら：Electrochemical Impedance Analysis for Fuel Cell 2 | LinkedIn

Previously, Electrochemical Impedance Analysis for Fuel Cell | LinkedIn

Preface

(1) Four-wheeled vehicle market

(2) Green vehicles

(i) BEV

(ii) FCV

(iii) FC-Stack/Battery power ratio

(a) Toyota (FC-HEV)

(b) Renault (FC range extender)

(d) Honda i-MMD-based?

(e) Others?

Main Topic: PEFC (Polymer Electrolyte Fuel Cell)

(1) PEFC Equivalent Circuit Model

According to Matsumoto, the equivalent circuit model of a PEFC is composed of

Here, Ra, Cd, and Rr denote the activation polarization resistance, electric double layer capacitance, and ionic/electronic resistance, respectively.

Ra-Cd high-frequency component is mainly attributed from the activation polarization on water generation at the cathode. The H2O generation from O2 takes place after

This process takes place at the solid-liquid-gas three-phase interface, thus, an electric double layer capacitance must be included in the model.

Rr low-frequency component is composed of

(2) PEFC Durability

According to Osaka Gas, the main deterioration factors are

(3) PEFC Control

Appendix

さて、コンバインド発電以外の定置型燃料電池の話をしていないのは、①ほぼ全量輸入しなければならない都市ガス・プロパンガスの消費量を増やす家庭用燃料電池などそもそも愚策と考えていること、②コジェネが経済合理性の前提だが家庭でそもそもたいした熱需要が無いため家庭用燃料電池などそもそも愚策と考えていることによる。

[1] Pobitra Halder, Meisam Babaie, Farhad Salek, Nawshad Haque Russell Savage, Svetlana Stevanovic, Timothy A. Bodisco, Ali Zare, "Advancements in hydrogen production, storage, distribution and refuelling for a sustainable transport sector: Hydrogen fuel cell vehicles," International Journal of Hydrogen Energy (2023).

Abstract
Hydrogen is considered as a promising fuel in the 21st century due to zero tailpipe CO2 emissions from hydrogen-powered vehicles. The use of hydrogen as fuel in vehicles can play an important role in decarbonising the transport sector and achieving net-zero emissions targets. However, there exist several issues related to hydrogen production, efficient hydrogen storage system and transport and refuelling infrastructure, where the current research is focussing on.
ここからわかるように、以下、もっぱら水素インフラの話です。
This study critically reviews and analyses the recent technological advancements of hydrogen production, storage and distribution technologies along with their cost and associated greenhouse gas emissions. This paper also comprehensively discusses the hydrogen refuelling methods, identifies issues associated with fast refuelling and explores the control strategies. Additionally, it explains various standard protocols in relation to safe and efficient refuelling, analyses economic aspects and presents the recent technological advancements related to refuelling infrastructure. This study suggests that the production cost of hydrogen significantly varies from one technology to others.
The current hydrogen production cost from fossil sources using the most established technologies were estimated at about $0.8–$3.5/kg H2, depending on the country of production. The underground storage technology exhibited the lowest storage cost, followed by compressed hydrogen and liquid hydrogen storage. The levelised cost of the refuelling station was reported to be about $1.5–$8/kg H2, depending on the station's capacity and country. Using portable refuelling stations were identified as a promising option in many countries for small fleet size low-to-medium duty vehicles. Following the current research progresses, this paper in the end identifies knowledge gaps and thereby presents future research directions.
間はすっ飛ばします。
Discussions and future research perspectives
Research on hydrogen production to utilisation in the transport sector has received immense attention in recent years, resulting in significant technological advancement. However, there still exist several challenges that are required to be addressed. Therefore, this paper has summarised some suggestions for future research directions as follows:
The transport of hydrogen from a central production facility to a refuelling station is a major issue as it requires a significant infrastructure cost, which increases the levelised refuelling cost. On-site small-to medium-scale hydrogen production using a mature production technology, such as electrolysis, with renewable electricity (Fig. 20) can avoid transport from the production site to the refuelling station and thereby reduce the cost of hydrogen to the customer. Some companies have developed on-site electrolysis hydrogen generator units with a generation capacity of 20 kg/day to >1000 kg/day, and a few of them are already in the implementation stage in Europe, USA and Canada [17,[233], [234], [235], [236], [237], [238]]. However, the renewable energy sources are uncertain and variable in nature with geographical location and season which can affect the overall hydrogen refuelling network. Therefore, country-specific feasibility studies of hybrid energy systems such as solar-wind-grid integrated on-site electrolysis, considering the uncertainty of renewables are required to understand the financial return of the investment in that specific location.
On-site H2 productionには水素輸送を必要としないってメリットは有るんだが、RE100％だと「燃料を必要量供給できるかわかりません」って話になってしまう。
したがってそこは系統につないで「燃料を必要量必ず供給します」ってしとけばいいわけ。「できるだけ再エネ電力を使いますけど」ってのがまあ限界なんでしょうけど。
Despite the higher cost of hydrogen production from water electrolysis compared to other production routes, it is considered as the cleanest technology to produce hydrogen from water with oxygen only as the waste from the process and has received interest due to environmental concerns associated with the use of natural gas and coal. However, the use of freshwater can cause water stress. Therefore, seawater can be an emerging alternative for producing green hydrogen via electrolysis. Seawater electrolysis is still in early development stage and numerous fundamental research is going on in laboratory scale investigations. For instance, the major challenges associated with the use of seawater in the electrolysis process include corrosion and chlorine production, which can be suppressed through pre-desalination, costing about $0.7–2.5 per m3 of water [239]. Additionally, researchers are currently focussing on direct electrolysis of seawater and working on the development of self-driven in-situ membrane purification process, new electrode or catalyst design to suppress chlorine oxidation/corrosion problems [[240], [241], [242], [243]]. However, effects of dissolve impurities and other ions such as sulphate, carbonate calcium and magnesium on the competitive reactions and long-term performance stability is still unclear. The standardisation of electrolyte and optimisation of process conditions such as electrolyte composition, current density and electrolysis time with newly developed catalysts for direct electrolysis are critical for commercialisation of seawater electrolysis, as the composition of seawater significantly varies across the world. It is also necessary to understand how each of the approaches of seawater electrolysis is economically feasible, considering the transport of hydrogen from the production site (near to sea) to refuelling stations (far away from the sea).
真水無いとこは海水使ったらどや言うてるんだけど、確か日本の船でやってるんだよね。できないことは無いってこと。脱塩など付加的なコストがかかるけど。
Hydrogen storage at ambient temperature using biomass-based carbon material is gaining interest over other materials, such as MOF, metal hydride, and liquid organic hydrogen carriers due to the renewability, low cost and ease of production. Biomass derived adsorbent-based hydrogen storage technology is in laboratory scale research stage. Therefore, a number of issues and fundamental knowledge gaps on the structure of feedstock for carbon material production, the role of inherent inorganics of biomass, storage capacity improvement, the adsorption-desorption cycle and an efficient hydrogen extraction strategy still need to be addressed for developing scale-up biomass-based efficient hydrogen storage systems and achieving the target of DOE.
高圧タンクだけじゃなく、他にも水素貯蔵の方法は有りますよって話。
ただ、自動車には高圧で充填しなければならないし、ササっと短時間で充填しなければならないので高圧タンクはやっぱり必要になるんだけど。ここにものすごいコストがかかるわけ。
だから、俺は再エネ水素は水素火力発電用なんだろうなと考えているわけ。水素生産サイトは電力不安定で停電を起こしそうなところにつくっておけばいいわけ（均すことが必要なサイトにつくっておけばいいわけ）。系統なので再エネ電力も再エネ以外の電力も混じっているんだけどそれは何でもいいわけ。
ま、国ごとに事情は違うのでね。日本はそうしたらいいだろうってだけ。
Temperature rise during fast refuelling of high-pressure hydrogen is a major technical challenge where a number of methods and strategies, such as control of refuelling rate, multi-stage refuelling and pre-cooling, have already been investigated. However, hydrogen mass flow rate control can increase refuelling time, pre-cooling can require high energy and higher number of stages can increase capital cost. The integration of refuelling rate control with the pre-cooling strategy can reduce the energy consumption while achieving the target of gas temperature and refuelling time. Therefore, experimental investigation of performance (energy consumption and ability to meet standard protocols) of coupling two or more strategies and their economic feasibility assessment would be interesting.
水素充填設備にコストがかかりますよって話の続き。
めんどくさいのよ、FCV。だから、長距離輸送トラック・バスとか鉄道とか船とか、頑張ってタクシーくらいまでかなと思うわけ。
Insufficient refuelling infrastructure is a major challenge for the commercialisation of hydrogen fuel cell vehicles, particularly for long-haul vehicles. An effective mapping and assessment are required prior to the development of refuelling infrastructure. A few studies have focussed on the planning and design of refuelling infrastructure for some countries [30,244,245]. However, more geographical studies are required to develop a GIS-based methodology considering the current vehicle's facility and future target. The GIS-based methodology, considering hydrogen delivery options and customers availability will help to determine the ideal location for setting up refuelling infrastructure and thereby develop policies for future expansion.
水素ステーションの配置の話をしとるでしょ。めんどくさいのよ、FCV。だから、長距離輸送トラック・バスとか鉄道とか船とか、頑張ってタクシーくらいまでかなと思うわけ。
Mobile hydrogen refuelling stations are promising alternatives to stationary refuelling stations for small fleet size, as the high capital costs of stationary refuelling stations is not economically attractive for a small fleet. Future research should focus on the supply chain and refuelling network design of portable stations for large fleet sizes and heavy-duty vehicles, considering the comparative economic feasibility assessment with stationary refuelling stations.
Electrochemical Impedance Analysis for Fuel Cell | LinkedInでも話をしたがSTOR-Hのような水素カートリッジを使った小型車の話な。
Conclusions
ま、正直言って「そんなことわかってますわ」って話なんですよ。ただ、「認識された」ってことが大事なの。
Hydrogen is a promising energy carrier which can store and deliver energy for the transition of future transport and heat sectors into sustainable options. This paper critically reviews the technological advancements, prospects and challenges of hydrogen production to refuelling into fuel cell vehicles to promote decarbonisation of the transport sector. The summary of key aspects, including efficiency, cost and associated emissions of major hydrogen technologies is highlighted in Table 3. Following a detailed literature review, this paper has drawn several conclusions as follows:
The costs of hydrogen production by well-established fossil-based technologies such as SMR and CG are competitive to the DOE target; however, these technologies have shown significant GHG emissions, which contradicts net-zero goals. In this case, renewable electricity-based electrolysis can be promising in the long run.
Carbon-based materials such as activated carbon, carbon nanotubes and nanofibers show promising hydrogen storage capacity at cryogenic conditions. On the other hand, metal hydrides exhibit superior hydrogen uptake capacity at ambient conditions.
The temperature rise in the fuel tank/cylinder decreases with the increase in initial pressure and gas temperature; however, it increases with the increase in mass filling rate and ambient temperature. The temperature rise issue can be controlled by controlling the hydrogen flow rate, pre-cooling the inlet temperature and refuelling at a multi-stage initial pressure.
The levelised cost of hydrogen at a refuelling station can be reduced by increasing the utilisation capacity of the station, fleet size and production volume of station equipment and reducing the hydrogen production cost. Portable refuelling stations show high potential for small fleet sizes.

ところで、天然ガス改質（Steam Methane Reforming: SMR）は一番安いから、例えば農業肥料生産用のアンモニアつくるときなんかはこれで原料の水素をつくってるんだが、燃料として使うときはちょっと馬鹿らしい。わざわざ水素なんか作らずにそのまま燃やせば？って感じですわな。価格も上下するし。
石炭ガス改質（Coal Gasification）もだいたい同じくらいのコストなんだが、こいつは石炭のままじゃ自動車用の燃料には使いづらいので水素にするってのは意味が有る。国産石炭が有ればエネルギー安全保障の観点からやってもいいでしょう。中国なんかはこの例だね。
褐炭などそのままでは発火リスクが有って輸送できない燃料は改質して水素にするってのもエネルギー安全保障上有効な方策だ。
再エネ水素（Electrolysis）は高いね。ただ、再エネを増やしていくと変動調整用の電源が必要になり、化石燃料を使用しないとなるとどうしても再エネ電力に余剰が有るときに水素でもつくって（長期備蓄が必要な場合はこれからアンモニアでもつくって）貯蔵しておいてこれを火力発電に使うしかないってことになる：H2 & NH3 Combustion Technologies (2020).