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15
Lithiated Carbons

Martin Winter and J¨ urgen Otto Besenhard †

15.1
Introduction

The rapid proliferation of new technologies, such as portable consumer electronics
and electric vehicles, has generated the need for batteries that provide both high
energy density and multiple rechargeability. In order to accomplish such high
energy density batteries, the use of electrode materials with high charge-storage
capacity is inevitable. Considering thermodynamic reasons for the selection of
an anode material, light metals M, such as Li, Na, K, or Mg, are favored as
they combine outstanding negative standard redox potentials with low equivalent
weights. However, a realization of batteries using these metals as active anode
materials is in most cases not possible because the strong reducing power of the
metals results in a spontaneous reaction in contact with an electrolyte.
Among the light metals M, only metallic lithium shows a chemical and electro-
chemical behavior which favors its use in high energy-density batteries [1, 2]. In
+
suitable nonaqueous electrolytes ‘passivating’ films of Li -containing electrolyte
decomposition products, spontaneously formed upon immersion in the electrolyte,
protect the lithium surfaces. These films act as a ‘sieve,’ being selectively permeable
+
to the electrochemically active charge carrier, the Li cation, but impermeable to
any other electrolyte component that would react with lithium, that is, they behave
as an electronically insulating solid/electrolyte interphase (SEI) [3–5].
The composition, structure, and formation process of the SEI on metallic
lithium depend on the nature of the electrolyte. The variety of possible electrolyte
components makes this topic very complex; it is reviewed by Peled, Golodnitsky,
and Penciner in Part III, Chapter 16 of this handbook. The types and properties
of liquid nonaqueous electrolytes that are commonly used in lithium cells are
reviewed by Barthel and Gores in Part III, Chapter 17.
The observation of the kinetic stability of lithium in a number of nonaqueous
electrolytes was the foundation of the research on ‘lithium batteries’ in the 1950s,
and the commercialization of primary (not rechargeable) lithium batteries followed
quickly in the late 1960s and early 1970s [2, 6–12]. Today, primary metallic lithium
systems have found a variety of applications, for example, military, consumer

Handbook of Battery Materials, Second Edition. Edited by Claus Daniel and J¨ urgen O. Besenhard.
 2011 Wiley-VCH Verlag GmbH & Co. KGaA. Published 2011 by Wiley-VCH Verlag GmbH & Co. KGaA.