Page 64 - ESJ – ENERGY STORAGE JOURNAL

ENERGY STORAGE HEROES: MICHEL ARMAND

“I also started on my own initiative “The CNRS did not bother me when
work on Prussian Blues as cheap, non- “I literally took the first I did not publish for five years, and let
stoichiometric iron derivatives. I was me supervise students before defend-
quite surprized that neither Bob Hug- flight out to Texas to meet ing my thesis. In retrospect, the results
gins nor Stan Whittingham realized John Goodenough to of my PhD should have been submit-
immediately the importance of inter- offer him a collaboration ted to prestigious journals,” he says.
calation for battery operation as their “But I was already into the induction
use for impedance measurements was within a Hydro-Québec- period for polymer electrolytes. I ben-
a close concept.” University of Texas- efitted from great tolerance at the be-
On his return to France in early ginning of my career and this helped
1972, Armand rekindled his doc- Université de Montréal creativity.”
toral research on intercalation com- triangle” The rationale behind polymer elec-
pounds for solid-state batteries at trolytes was that they would be pref-
what is now Laboratoire d’ionique et erable contact-wise to hard ceramic
d’électrochimie du solide, a large labo- had realized the potential of these materials or glasses when intercala-
ratory in Grenoble devoted to solid- compounds for electrochemistry. Paul tion compounds were to be used as
state electrochemistry. Hagenmuller in Bordeaux and Jean electrodes, with volume change. Ini-
In 1972, he attended the NATO con- Rouxel in Nantes, who had been in- tially the idea seemed bizarre, as poly-
ference on Fast Ion Transport in Solids vestigating non-stoichiometric com- mers are known for their insulating
in Belgirate in northern Italy, where he pounds, saw their work come into the properties while ions were thought
presented the use of ternary graphite limelight and extended. to move only in channels or in two-
intercalation, a new family of intersti- For the scientific/engineering com- dimensional openings with an optimal
tial compounds derived from graphite, munity, intercalation electrodes came size, like b-alumina, which polymers
as promising candidates for solid-state as a possible competitor to batteries do not provide.
electrode materials. using b-alumina (sodium/sulfur), with Armand selected polyethylene oxide
Armand’s paper and metallurgist Wynn Jones and British Rail in the after ceramics researcher Peter Wright
professor Brian Steele of Imperial Col- UK. at the University of Sheffield had
lege’s paper, which clearly suggested There was also at Argonne Na- shown in 1975 that it is a host for a
the use of solid solution electrodes in tional Laboratory a huge programme number of sodium or potassium salts
his own terms such as Na TiS were on Li(Al)/FeS batteries using molten and displayed some conductivity.
2
2,
x
the starting point of what was to be- LiCl/KCl as electrolyte, but work- Here he established the electrical
come a booming activity on intercala- ing at 350°C, where the corrosion properties of the polymer-salt com-
tion chemistry during the 1970s. from the molten salt proved to be a plexes formed with selected lithium
Whittingham, for example, became crippling handicap. In 1974 Armand salts, and pointed out that these mate-
involved at Exxon in the programme joined the French Centre National de rial, would be useful for batteries. A
for making batteries using LixTiS2 la Recherche Scientifique (CNRS) as a little earlier in 1978, he obtained his
as an electrode material. Moreover, research associate, He became its di- PhD in Physics cum laude.
the solid-state chemistry community rector of research in 1989. This work contained the first gen-

The rationale behind polymer electrolytes was that they would be preferable
contact-wise to hard ceramic materials or glasses, when intercalation compounds
were to be used as electrodes with volume change.

62 • Energy Storage Journal • Summer 2019 www.energystoragejournal.com