In Situ Fe K-Edge X-ray Absorption Fine Structure of a Pyrite Electrode

Li/Polyethylene Oxide(LiClO4)/FeS2 Battery Environment ... Materials Science and Engineering, Case Western ReserVe UniVersity, CleVeland, Ohio 44106- ...
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Abs. 105, 205th Meeting, © 2004 The Electrochemical Society, Inc.

The discharge properties of FeS2 cathode

10hour

prepared by mechanical alloying for lithium

15hour

batteries

20hour

S.W. Lee*, W.H. Jung**, I.S. Ahn**, H.J. Ahn*,

30hour

K.W. Kim*, and J.H. Ahn*

40hour

Information Technology Reserch Center for Energy

60hour

storage and conversion*

20

Division of Materials Science and Engineering

ERI

Gyeongsang National University**.

batteries have been driven by remarkable performance improvements of alkaline batteries to meet everincreasing power demands of electronic devices. FeS2 is attractive as cathode material in lithium batteries because of its low material cost and high specific energy density. been studied

on

Li-Al/FeS2

molten

salt

rechargeable batteries at 400°C and Li/FeS2 primary batteries at ambient temperature.[1] Jiang et al. made various Fe-S compounds by planetary ball milling.[2]. They studied on Li/FeS cell. However, there was few studies on the electrochemical properties of synthesized FeS2. In this paper, FeS2 powder was prepared by attrition ball mill. We studied on the electrochemical properties of FeS2 cathode of lithium batteries. 2.Experimental The FeS2 powder was synthesized by ball milling from pure powders of sulfur and iron under an Ar atmosphere. FeS2 electrodes were prepared from a mixture of FeS2, carbon black (Aldrich) and PVdF-co-HFP (kyna 2801). FeS2 slurry was coated on Al current collector. After drying at 60 

50

60

70





 





































 



80

Fig.1. XRD patterns of FeS2 composite powder for

c) 20hours, d) 30hours, e) 40hours, f) 60hours

Recent research and development efforts in Li/FeS2

has

40

 

various ball milling time . a) 10hours, b) 15hours,

1.Iintroduction

It

30



in vacuum, Li/FeS2 cells were assembled

in stainless steel cell holders made from a Swagelok type cell. Discharge-charge tests were conducted using a WBCS3000 between 0.9V and 3.0V with current density of 50mA/g-FeS2 at room temperature. The structure of the FeS2 powder was characterized by XRD. 3. Results Fig.1 is the changes of XRD patterns as a function of ball milling time. Iron and sulfur remained until 15hrs ball milling. After 30hrs, iron and sulfur change to FeS2.

4. Reference [1] Yang Shao-Horn, Steve Osmialowski and Quinn C. horn. Journal of the elctrochemical society, 149 (11) A1499 (2002). [2] J. Z. Jiang, R. K. Larson, R. Lin, S. Morpu,I. Chorkendorff, K. Nielsen, K. Hansen, and K West. Journal of solid state chemistry 138, 114(1998)