Progress of Hydrogen Storage and Container Materials

1. H2 STOR-18 Progress of Hydrogen Storage and Container Materials YiYi LI* YuTuo ZHANG February 26, 2008 Cocoa Beach, Florida Institute of Metal Research, Chinese Academy of Sciences

2. Heilongjiang Jilin Inner Mongolia IMR Xinjiang Beijing Liaoning Gansu Tianjin Hebei Ningxia Qinghai Shanxi Sandong Jiangsu Henan Anhui Shanghai Tibet Sichuan Hubei Zhejiang Chongqing jiangxi Hunan Fujian Yunnan Guangdong Taiwai Guangxi Hongkong Macau Hainan Location of IMR Shenyang

3. Thanks for my colleagues Dr.Huiming CHENG Dr.Ping WANG Dr.Dong CHEN Dr.Lijian RONG Dr.Xiuyan LI Prof. Lian CHEN Prof.Luming MA Prof.Cungan FAN

4. Outline • Introduction • Hydrogen Storage Materials • Hydrogen Container Materials • Conclusions

5. 1. Introduction • Premier Wen Jiabao tasked that up to 2020 China’s energy consumption per unit GDP decreases of 20%. • Premier Wen also urged that those consuming more energy and releasing more pollutants have to in a bid. From: http://www.efchina.org/FHome.do a speech addressed to the national working teleconference on energy saving and pollutants reduction on April 27, 2007.

6. The Development Policy for China Automobile • Up to the end of 2007, there are 160 million automobiles in China. • In order to decrease emission of automobiles, Chinese government supports R&D of clean fuel such as ethanol, NG to hybrid, electric vehicles. • Pushing and encouraging EV development. • Developing new TiAl valves for cars.

7. Alternative Fuel Vehicles • There are 215,000 gas-powered vehicles which are operating with 712 gas-refilling stations. • The number of natural gas-powered vehicles has been ranked the seventh and liquefied petroleum gas vehicles on the 11th in the world.

8. Fuel Cell Vehicle Development in China • Hydrogen fuel cell vehicles start development in 1990s. • There are 30kW car and 60kW bus as well as 100kW FC bus. • 2008: during the Olympic Games it has demonstration buses with hydrogen fuel cells in Beijing. 60 kW 100 kW

9. 2. Hydrogen Storage Materials • AB5 Alloy • AB2 Nanocrystalline Alloy • Ti-NaAlH4 Complex Hydride • Mg/MWNTs Composite

10. The AB5 Hydrogen Storage Alloy • The AB5 hydrogen storage alloy for the production of NiMH batteries has been industrialized in China or international market. • In 2005, global sales volume of the alloy was around 20,000 tons, 60% of which was mainly consumed by small NiMH batteries and with proportion of 40% for dynamic batteries. • Production scale of the alloy reached 12,000 tons in China in 2005. It is estimated that global demand for hydrogen storage alloy will exceed 40,000 tons in 2010. *

11. AB2 Nanocrystalline Alloys • Zr-based AB2 Laves phase alloys consist of cast polycrystalline and nanocrystalline structure. Nanocrystalline microstructure could be obtained from quenching of melt-spun alloys after annealing. Composition AB2-1 alloy Zr[(Ni V Mn Co)1-ySny]2+(y=0,0.025,0.05) AB2-4 alloy(Zr1-xTix)(Ni V Mn Co) 2+(0.05<X<0.15,0<<0.3)

12. SEM Micrographs of the Cast Polycrystalline AB2 Alloys (a) AB2-1 alloy (b) AB2-4 alloy • Microstructures of AB2-1 alloys consist of cubic C15 Laves phase, hexagonal C14 Laves phase and of AB2-4 is C15 • The white one of non Laves phase in AB2-1 and AB2-4 is Zr9Ni11 and Zr7Ni10, respectively.

13. 100nm TEM Micro-analysis QAB2-4 Alloy The transmission electron microscopy (TEM) and correlated electron diffraction patterns of quenched QAB2-4 alloy. (a) bright field (b) SAED pattern of the white area It was clearly observed that white area has turned into amorphous phase, indicating bright continuous ring.

14. TEM Micrographs and SAED Patterns of QHAB2-4 (a) bright field (b) dark field (c) SAED patterns • The electron diffraction pattern is discontinuous rings consisting of scattered dots at annealing temperature of 1173K, the alloy has turned into nanocrystalline completely and the grain size is about 80nm.

15. 380 360 340 320 300 Discharge Capacity(mAh/g) 280 AB2 -1, as-cast 260 QHAB2-1-heat-treated at 1173K AB2- 4, as-cast 240 QHAB2-4-heat-treated at 1173K 220 0 50 100 150 200 250 300 Charge-discharge Cycle (n) The Charge-discharge Cycle-life for QHAB2-1 and QHAB2-4 The discharge capacity of nanocrystalline electrodes can be increased to 370mAh/g and cycle life decreased only 3% after 300 cycles. *

16. Ti-NaAlH4 Complex Hydride Target: LiBH4 Al(BH4)3 Medium & long-term NaBH4 LiAlH4 MgH2 Near-term NaAlH4 CNT kgH2/m3 • We are interested in the sodium aluminum hydride system.

17. 5 +KH+Ti 5 4.7% 4 +LiH+Ti After KH addition 4 3 H-amount desorbed, wt.% +Ti 2 3 H-capacity, wt.% 1 DH at 150oC 2 High and stable! 0 1 0 2 4 6 8 10 Time, h 1 2 3 4 5 6 7 8 9 10 Cycle Number High Capacity of KH+Ti co-doped NaAlH4 From P.Wang H.M.Cheng Potassium hydride and Titanium • After adding of potassium hydride and Titanium to NaAlH4, the hydrogen capacity is high and stable.

18. Ti with TiH2 doped to NaAlH4 Kinetic performance Cycling performance Direct utilization of metallic Ti as dopant to prepare Ti-doped NaAlH4 offers the same performance as TIH2.

19. cycled As-milled Ti in situ formed TiH2 In situ formed Ti hydride keeps its phase stability in ab/desorption cycles

20. (b) (a) (a) (b) Morphological Observation DH performance Back Scattering Electron images EDS analyses (a) (b) Milling time for 1 h, the sample is metallic Ti. While in the 10 h, particles consist of nanocrystalline TiH2. *

21. Composite of Mg/MWNTs Mg- 5 wt.% MWNTs were developed by a catalytic reaction of ball-milling with different materials such as matrix Mg magnesium, multi-walled carbon nanotubes (MWNTs).

22. XRD Patterns of Hydrogen Storage Composite Mg/MWNTs From: Chen Dong et al (a) Without ball milling; (b) Ball milling for 0.5h; (c) Ball milling for 3 h; (d) After hydriding and dehydriding cycles. XRD peak of Mg disappeared and hydride MgH2 appeared after hydriding and dehydriding cycles.

23. 1: 298 K, 2: 373 K, 3: 473 K, 4: 553 K Absorption & Desorption Kinetics for Mg- 5 wt.% MWNTs • At each temperature, 80 % of maximum hydrogen storage capacity can be obtained in 20, 15, 2 and 1 min, respectively. • The largest hydrogen absorption rate exhibited at 553K • The hydrogen desorption rates were as the same.

24. at 2.0 MPa hydrogen pressure PCT Curves for Composite Mg/MWNT-H2 System The maximum amount of hydrogen storage capacity of Mg-5 wt.% MWNTs is 0.4wt.%,3.4wt.%, 5.7wt.%, 6.2wt.% respectively. *

25. 3. Hydrogen Container Materials • FeNiCr stainless steel and FeNiCr stainless steels strengthened with N and Mn. • Nanosize -precipitates strengthened superalloys. Two kinds of alloys can be applied to hydrogen resistant container:

26. The container of thermal hydrogen charging

27. Effect of thermal H2 charging on mechanical properties Thermal H2-charged: 300 oC, 10days, 10MPa, H2 saturated • 20# FeNiCr stainless steel • 40# & 50# FeNiCr stainless steels strengthened with N and Mn

28. The Stability of Austenite Alloy Used for H Storage Container Metastable austenite transformed -  or  --after cooling or deformation, then the hydrogen brittleness or degradationcan occur. From:http://www.outokumpu.com/ - Austenite  -Martensite *

29. Nano-  Strengthened Fe-based Alloys Excellent combination of • Hydrogen resistance • High strength at room temp. • High temperature strength • Fe-based alloys better than Ni-based alloys Hydrogen resistance of nano-  strengthened Fe-based alloys is better than other precipitates strengthened alloys.

30. Tensile Properties of the Alloys Thermal H2-charged: 300 oC, 10days, 10MPa, H2

31. Typical Microstructure   size should be controlled within 10 nm, then the H2 could not be settled in the interface between -. Then, the degradation of the alloy become small.

32. Other precipitates  phase should be coherent to the Matrix *

33. 4. Conclusions • AB2 nano-crystalline alloy, Ti-NaAlH4 complex hydride and Mg/MWNTs composite are promising hydrogen storage materials. • It is important to use the stable austenite alloys for hydrogen container materials.

34. Bei Jing Huan Ying Nin One world One dream Welcome to Thank you for your attention