ISSN 1070-4272, Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 12, pp. 1952!1956. + Pleiades Publishing, Inc., 2006.
Original Russian Text + O.V. Karlova, I.A. Kedrinskii, E.A. Chudinov, M.V. Yakovleva, 2006, published in Zhurnal Prikladnoi Khimii, 2006, Vol. 79,
No. 12, pp. 1975!1979.
AND CORROSION PROTECTION OF METALS
A Negative Carbon Electrode in an Electrolyte
Containing Sulfur Dioxide
O. V. Karlova, I. A. Kedrinskii, E. A. Chudinov, and M. V. Yakovleva
Siberian State Technological University, Krasnoyarsk, Russia
Istochnik Battery Institute OAO, St. Petersburg, Russia
Received August 10, 2006
Abstract-The possibility of replacing the electrolyte based on imported ethylene carbonate with a domestic
-containing electrolyte based on propylene carbonate was considered for the example of operation of
the negative electrode of a lithium3ion battery.
The standard electrolyte for lithium3ion batteries
commonly contains ethylene carbonate (EC), which is
not presently produced in Russia. At the same time,
it has been shown in the development of primary li-
thium power sources that SO
based on propylene carbonate (PC) can form on car-
bon electrodes surface layers similar in properties to
those produced by EC-containing electrolytes .
However, the existence and stability of intercalation/
deintercalation of lithium ions into/from the carbon
matrix with a surface layer formed by SO
To actualize the possibility of using a SO
ing electrolyte, it was necessary to complete studies
of the electrochemical behavior of carbon materials
-containing electrolytes and to demonstrate
the stability of operation of not only negative, but
also positive electrodes and of the cell as a whole.
This study is concerned with the behavior of
the carbon electrode in a PC-based electrolyte con-
. It was established that the main charac-
teristics determining the working capacity of a neg-
ative carbon electrode in a lithium ion battery are
the expenditure of electricity for the formation of sur-
face layer during the first charging, preservation of
the surface layer on the charged and discharged elec-
trode and on that subjected to cycling, stability of
charging-discharge characteristics, and charge pre-
servation in storage (self-discharge).
We used as active material a powdered spectral-
ly pure graphite (SPG) with grain size d < 40 mm.
The carbon of this type was used for two reasons.
First, it is the standard material [TU (Technical Spe-
cification) 16-538-240374] produced in Russia. Sec-
ond, this material contains, by virtue of its main ap-
plication, no impurities of spectrally active elements,
which makes impossible a number of reactions lead-
ing to an irreversible immobilization of lithium ions.
The electrode paste had the standard composition (%):
SPG 85, acetylene black 5, and binder 10. As binder
was used FP-42D or F2-ME. The electrodes fabricated
contained about 2 mg cm
SPG. A 1 M solution of
in PC, with an SO
content of 13320, served
as the electrolyte. The electrolyte volume in the cell
was 2.5 ml. The humidity of the electrolyte, as deter-
mined by the Fischer titration method, was 100 ppm.
A plate of metallic lithium served as the counter
electrode, so that the cell of composition C/Li was, in
fact, subjected to electrolysis. The electrolysis was
performed at i = 0.063 0.127 mA cm
of the apparent
surface area (35.3375.0 mA g
In the first charging, a surface layer responsible
for the working capacity of an electrode in a battery
is formed on the electrode surface. It should be noted
that the first-cycle charging curve of the SPG elec-
trode in the SO
-containing electrolyte is well re-
producible. The charging curves obtained by con-
tinuous electrolysis and by the method of static cou-
lometric titration  in similar electrolytes (PC, 1 M
, 13% SO
and PC : DME = 7 : 3, 0.6 M
, 17% SO
) are presented in Fig. 1. It can
be seen that the curves largely coincide, especially
in the region corresponding to reduction of sulfur