Broussely, 1999 - Revew Batteries

Lithium insertion into host materials: the key to successfor Li ion batteries

M. Brousselya,*, P. Biensanb, B. Simonb

aSAFT, Advanced and Industrial Battery Group, BP 1039, 86060 Poitiers, FrancebSAFT, Direction de la Recherche, 111, Boulevard A.Daney, 33074 Bordeaux, France

Received 7 February 1999; received in revised form 28 April 1999

Abstract

The aim of this paper is to summarise the present situation in Li ion batteries, from a short historical perspectiveof the concepts and materials, to the present trends. It aims also at giving the scientists working in this field some

picture of the impact of the insertion material properties on the final cell characteristics. The market andapplications of lithium ion batteries, present and future, are also briefly discussed. # 1999 Elsevier Science Ltd. Allrights reserved.

Keywords: Lithium insertion; Li ion batteries; Final cell characteristics

1. Introduction

In 1990, Sony [1] surprised the battery world by

abandoning rechargeable lithium metal battery devel-

opment, in which they had been deeply involved for

several years with a Li/MnO2 couple, to introduce a

new concept, which they named Li ion. Based on pre-

vious scientific studies and some early prototype results

[2], engineers from Sony were able to demonstrate that

disordered non-graphitisable carbons (hard carbons)

can also insert lithium, using an appropriate electro-

lytic solution and a suitable electrode technology.

Since this time, a lot of research and development

work has been increasingly carried on worldwide, and

very rapid and significant improvements were made to

the insertion materials used in these batteries. For

example, crystallised carbons can now be used without

exfoliation, bringing useful improvements to cell vol-tage and energy. Considerable economic incentiveslinked to the huge development of portable electronic

devices such as cellular phones or notebook computers,greatly stimulated this R&D activity, in both the tech-nology aspects and the fundamentals.

Much progress can be still anticipated for the future,and this type of battery, up to now limited to smallsizes, will find other applications in the business forlarger batteries. Low material cost is one of the key

issues to make Li ion become a true multipurpose bat-tery system in the next decade.

2. From lithium to lithium ion, a long story

2.1. The early days

When the lithium battery concept began to stimulate

the brains of a few battery engineers early in thesixties, the rechargeable system was already uppermost

Electrochimica Acta 45 (1999) 322

0013-4686/99/$ - see front matter # 1999 Elsevier Science Ltd. All rights reserved.PII: S0013-4686(99 )00189-9

www.elsevier.nl/locate/electacta

* Corresponding author. Tel.: +33-5-4955-4829; fax: +33-

5-4955-5630.

E-mail address: [email protected] (M.

Broussely)

in their minds. In 1962, at the Electrochemical Societyfall meeting in Boston, Chilton Jr. and Cook [3] from

Lockheed Missile and Space Co. gave a presentationentitled Lithium Nonaqueous Secondary Batteries,which was probably the first paper ever presented in

this meeting on a lithium battery. The goal was a highenergy density and long cycle life battery to increasethe mission lifetime of satellites . . . which is now

becoming a reality, about 40 years later. Since thattime, a lot of research would follow, on a long journeythat would go through many dierent steps.

Many diculties had to be overcome at that time,from to find a stable electrolyte medium with lithium,to defining a reversible positive electrode material.Based on experience with aqueous systems, the aim

was to find an second kind electrode, using a lowsolubility metallic salt. Halides like AgCl, CuCl2 [4],CuCl [5] or CuF2, NiF2 were mostly investigated,

forming LiCl or LiF and the corresponding metallicphase during discharge. In their work, Chilton andCook used a metallic positive (Ag, Cu or Ni), and

formed lithium deposited in situ on Ni during the firstcharge, from the LiClAlCl3 electrolyte dissolved inpropylene carbonate.

The main drawbacks were the formation of solublecomplexes, like CuCl2, leading to irreversible self-dis-charge phenomena, and the large volume changes ofthe electrode during cycling. In addition, the electrical

insulating properties of the materials required a largeaddition of a conductive agent like carbon to the elec-trode.

2.2. An insertion material as reversible positive

A decisive step was passed when the development of

insertion compounds chemistry in several research lab-oratories [6] brought about a solution in the early sev-enties. These materials could at the same time host

lithium ions inside their crystalline structure, whilereducing transition metals from their higher oxidationstate. This so-called topotactical electrochemical reac-tion would occur reversibly, without major phase

change, and should be made easier by a significantconductivity or semi-conductivity. From that time, anew electrochemistry for energy storage would spring

up, involving more and more solid state chemistry. Inthe last two decades, the significant improvement ofscientific equipment for the investigation of crystalline

structure has been a decisive factor in the understand-ing and development of new materials.

2.3. A rechargeable lithium electrode?

Beside the problem of the positive electrode, lithiumcorrosion and dendrite formation on the negative side

created numerous problems, resulting in poor cyclingeciency and cell shorting.

Electrolytes have been extensively studied to try tosolve this problem, showing the major role of additivesand impurities in film formation. Many solutions were

proposed, from well known cyclic carbonates PC andEC to ether-based solutions, using for example 1,3-dioxolane [4], or 3-MeTHF [7]. The cell design, by

using a microporous polypropylene separator and spi-rally wound electrodes with sucient mechanical stressto reduce dendrite formation, proved also to be a criti-

cal parameter and led to a very significant break-through in the mid-eighties, with the first commercialrechargeable lithium products [8]. However, this tech-nology still suered from relatively limited cycle life

(currently less than 200), and more importantly poorsafety associated with the formation of finely dividedlithium powder upon cycling.

2.4. Replacing the lithium metal: the rocking chair

Li alloys with other metals (like aluminum) appearednaturally as the first solution to replace Li metal, butthey suer from severe morphological changes upon

cycling due to large volume changes [9]. Li diusioninto the alloys is also a limiting factor, especially atambient temperature. Except for special use at low

rate and very limited depth of discharge (coin cells),the use of Li alloys with metals (mainly Al) has beenunsuccessful.

Insertion of lithium into graphite via a chemicalroute had been known since 1955 [10], and the electro-chemical insertion of lithium into graphite was investi-

gated in 1976 by Besenhard [11]. It was proposed as areversible negative material in secondary lithium bat-teries by Armand in 1978 [12]. However, severe pro-blems of exfoliation were experienced in organic

electrolytes, limiting the apparent viability of this con-cept to polymer electrolyte cells [13]. Later, followingfirst investigations in molten salt batteries [14] Basu

described in 1982 a battery using LiC6 anode and or-ganic electrolyte, more specifically Dioxolane, in a USpatent [15]. However, the positive material did not

contain lithium ions at the initial state (NbSe3, V6O13,TiS2 were proposed), and carbon was chemically pre-lithiated before cell assembly. In 1980, the rockingchair concept, using two insertion compounds based

on metallic oxides or sulfides was proposed by Lazzariand Scrosati [16]. A LixWO2/LiyTiS2 cell wasdescribed, working at an average voltage of 1.8 V.

However, while this system could solve the lithiumelectrode problems, it was unable to provide the practi-cal energy density required to make it attractive com-

pared to existing rechargeable systems, and very farfrom the numbers which could be expected from a truelithium battery. Assuming exchange of 1 Li/mol, the

M. Broussely et al. / Electrochimica Acta 45 (1999) 3224

SamuelHighlight

SamuelHighlight

SamuelHighlight

SamuelHighlight

theoretical energy density (active materials only) is

about 150 Wh/kg compared to 520 Wh/kg for aLi/TiS2 cell. These comparative numbers may alsoexplain why eorts were so much focused on the

rechargeability of lithium metal, instead of insertioncompounds.

2.5. The Li ion

Finally, the discovery in the mid-eighties of theunexpected property of disordered carbon to insert

lithium [2] with a stable protective passivating layer,and the successful association with the high voltagepositive material LiCoO2 [1], led to what can now be

considered as the major breakthrough in new practicalbattery systems in the second half of the twentieth cen-tury.

3. The positive material

When insertion materials were proposed [12,17] as

the best solution for rechargeable non-aqueous bat-teries, the first materials which captured attention wasthe chalcogenides. The layered TiS2 was undoubtedly

the most popular [18,19], and has been extensively stu-died for years. Thanks to its stable layered structureand electronic conductivity, it provided high drain

capability and good reversibility. It was used as thepositive electrode material in the first marketedrechargeable lithium battery, by Exxon, which was a

coin cell for watches, using a LiAl negative electrode.

TiS2 stood for a long time as the standard positiveelectrode material, and was used in the development

stage of cylindrical spirally wound cells [20]. A lot of

other di- and tri-chalcogenides were studied, includingamorphous structures; see for example the review by

Abraham [21]. Layered thiophosphates, like NiPS3,were also proposed [22]. From this array of materials,

NbSe3 [23] was used at the development stage oflithium batteries, and MoS2 [8] was used up until the

beginning of mass production.

Utilisation of metal oxides as reversible insertionelectrodes was proposed quite early, for example

MoO3 in 1971 [24] or WO3. A large number of ma-terials were investigated, including chromium oxides

[25] and vanadium oxides [26], which 10 years agowere probably the most studied of the oxides.

Manganese oxide MnO2 and V2O5 are used in com-mercial rechargeable coin cells using LiAl as the nega-

tive electrode. A vanadium oxide VOx is also thepositive material in the polymer electrolyte Li battery

developed by Hydro Quebec and 3 M.

Although Mizushima and Goodenough publishedquite early the possible use of LixCoO2 or LixNiO2 in

1980 [27], relatively little attention was paid at the timeto these materials, probably because the high working

voltage was considered as a drawback for stability inorganic electrolytes. Some work was, however, per-

formed [28], leading to the development of suitable

electrolytes using pure carbonate solvent mixtures. Atthe same time, studies on spinel materials led to the

Fig. 1. First cycle of the three usual candidates as positive materials for Lithium-ion cells. Results obtained in coin cells versus

lithium, at C/20 rate and ambient temperature. Electrolyte was PC/EC/DMC (1/1/3) LiPF6. EOCV is 4.2 V except for LiMn2O4(4.3 V).

M. Broussely et al. / Electrochimica Acta 45 (1999) 322 5

SamuelHighlight

SamuelHighlight

SamuelHighlight

selection of LiMn2O4 as a competitive material, whichwas especially attractive for its potential low cost.Studies on positive materials moved then almost com-

pletely from sulfides to oxides and these three familiesof oxides are now the most used or studied. Theirmain features and trends for the future are described

hereafter.

3.1. LiCoO2 and derivatives

The reason for the choice of LiCoO2, which is now

the most prevalent positive electrode material, is basedon several considerations. Initially, as Sony decided tomove from Li metal to lithiated carbon, the positivematerial had to have a sucient working voltage to

compensate for the voltage loss on the negative side.Also, the material had to be fully lithiated at the dis-charged state, to build the cell with pure carbon.

Already studied in the frame of lithium metal batteries,LiCoO2 was available and fitted the needs completely.LiNiO2, with potentially a higher specific capacity [29],

was more dicult to prepare, because of the tendencyto form a Ni-rich nonstoichiometric phase. Manyindustrial makers now propose LiCoO2 materials notjust in Japan (NCI, SEIMI, Tanaka, Santoku . . .), but

also in Europe (Union Minie`re, Sogemet, . . . ) and innorth America (FMC, Union Minie`re (previouslyWestaim)).

Good electrochemical performance is obtained up to4.2 V versus Li/Li+, providing 150 A h/kg on firstdelithiation, and generally 140145 A h/kg reversible

capacity on cycling (Fig. 1). From the experience accu-mulated over several years in consumer cells, LiCoO2does not appear to present any strong technical draw-

back, compared with LiNiO2 (lower safety) andLiMn2O4 (fading, hot temperature behaviour). The

thermal stability is lower than with LiMn2O4 [30,31]but safe cells can be designed with 4.14.2 V end of

charge voltage. However, a small overcharge of thematerial leads readily to higher reactivity, as the ma-terial is more oxidizing and thermal stability is lower.

In fact, the material reactivity is strongly dependent onstate of charge, as shown on Fig. 2 which describes

dierential scanning calorimetry (DSC) spectra ofLiCoO2 as a function of end of charge voltage

(EOCV).Much research work on LiCoO2 has involved struc-

tural aspects of the material and its delithiated phasesand the optimisation of the synthesis process [3234].

A lot of work worldwide has also been dedicated topartial substitution of cobalt by other metals like

nickel, iron and manganese [3539]. More recently sub-stitution with aluminum [40,41] has shown an increase

of the average discharge voltage which was predictedby the theory involving the participation of oxygenions bonding in the oxidation-reduction process. It was

also demonstrated that a very small amount of mag-nesium has an impact on fading behaviour during

cycling [42].Up to now, however, these materials have not found

a practical application, as they have no significantpositive impact on the cost, which is the main draw-

back of LiCoO2. The elevated price of cobalt forbidsany practical use in large batteries (E.V., H.E.V, . . . ).

Industrial research is now concentrated more onenergy density improvement based on the electrode

formulation and the physical properties of the materialpowder.

Fig. 2. DSC behaviour of LiCoO2 for dierent EOCV from 4.2 V up to 4.7 V. Electrolyte is PC/EC/DMC (1/1/3)+LiPF6(1 M).

Scanning rate is 108C/min. Curves are shifted for a better legibility (each starting point=0 mW).


3.2. LiNiO2 and derivatives

LiNiO2 is almost not used in commercial cells

despite its excellent, probably the best, specific capacity

(185 to 210 A h/kg at 4.1 or 4.2 V, respectively), and

lower cost than LiCoO2. Practically, however, this ma-

terial did not have great success for dierent reasons: a

tighter synthesis process, a tendency to give higher fad-

ing with cycling and a lower thermal stability.

First, the synthesis of the material is more dicult

than that of LiCoO2, as illustrated by the number of

publications dedicated to this subject. The main pro-

blem is linked to the formation of a nickel over-stoi-

chiometric phase [4345] with general formulation

Li(1z )Ni(1+z )O2. These extra nickel ions with respectto stoichiometry lead to a low electrochemical per-

formance: a low amount of lithium extracted and poor

reversibility of electrochemical process. A phenomeno-

logical explanation was given by Delmas et al. [46] by

the formation of non-accessible sites around the nickel

in the lithium site after its oxidation during the first

cycle. Optimisation of the synthesis process can lead to

materials with low z values of z= 12%, but not less

up to now.

Fig. 3. Fading behaviour at 608C of LiNiO2 and LiNi(1M)MMO2 positive materials for M=Ti, Co or Co+Mg in coin cells withlithium counter electrode. Cycling was performed between 4.1 and 3 V in PC/EC/DMC(1/1/3)+LiPF6(1 M).

Fig. 4. Capacity fading during cycling of a 4/5A size prototype cells using magnesium substituted LiNi0.86Co0.09Mg0.05O2 material

and graphite negative electrode. Electrolyte=PC/EC/DMC(1/1/3), 1 MliPF6. Cycling at 258C and 608C, at C rate.


The second point, which limited extensive develop-

ment of LiNiO2, is the problem of capacity fading with

cycling. High losses in cycling have been reported for

pure LiNiO2, but these results might have been greatly

influenced by the way the material was produced. If

properly synthesised, the cycle life can be quite accep-

table, and no evolution of the structure of the material

is observed, even with tools like Rietveld refinements,

after as much as 1200 cycles [47]. However, this some-

what unreliable behaviour can be very much improved

by substituting other cationic elements for nickel.

Cobalt or magnesium demonstrates high eciency, as

shown on Fig. 3. These results were obtained at 608Cin small coin cells with lithium metal, which are good

test vehicles for comparison by greatly accelerating ca-

pacity fading on cycling. Even low amounts of mag-

nesium, close to 5%, are sucient to suppress

completely the fading of the material up to 4.3 V

Fig. 5. Incremental capacity of LiNiO2 (- - - -) and LiNi0.86Co0.09Mg0.05O2 (() at C/20 rate, in coin cells vs. Li. Electrolyte is PC/

EC/DMC(1/1/3)+LiPF6(1 M).

Fig. 6. DSC behaviour of LiNiO2+electrolyte, for dierent EOCV from 3.8 V up to 4.7 V. Electrolyte is PC/EC/DMC (1/1/

3)+LiPF6 (1 M). Scanning rate is 108C/min.


EOCV. This improvement is also illustrated in Fig. 4,

relating 400 cycles at 608C in complete prototype Liion cells with no particular fading observed. This

strong improvement of the cycling ability probablyoriginates in the suppression of the phase transitions

usually observed for LiNiO2 which disappear withmagnesium substitution as demonstrated in Fig. 5.

Improvement of reversibility and fading behaviour isalso observed by co-substitution of cobalt and manga-

nese of up to 40% of the nickel [48].Last but not least, the thermal stability of LiNiO2 is

significantly lower than the two other materials [30].This is partially due to the instability of nickel in the

oxidation state of 4, but it can also be seen as a draw-back of its very high capacity: the charged state at 4.1

V corresponds to composition close to Li0.33NiO2, farmore delithiated than for LiCoO2, for example. The

delithiation state of the material is a first order par-ameter of its thermal stability [31] as illustrated in Fig.

6. Thermal stability of delithiated nickel-rich phasescan be modified by substitution. Substitution by alumi-

num of 25% of the nickel cations for example was stu-died by Ohzuku et al. [49] while researchers from

FMC [50,51] obtain very nice thermal stability up to4008C with titanium and magnesium co-substitution,but higher charge voltage than usual is needed in bothcases. Moreover, eciency of the first cycle is signifi-

cantly reduced. Conservation of electrochemical per-formance associated with good thermal stability needs

multiple substitution, as illustrated in Fig. 7. The ther-mal stability of the doped material is similar to that of

LiMn2O4 in terms of temperature of reaction with elec-

trolyte, and the heat power related to electrochemicalenergy of the material (W h) is significantly lower.Substituted nickel-rich materials are therefore the

subject of increasing interest. Substituting other cationsfor nickel had produced a large and increasing numberof papers and patents. Almost half the periodic tableof elements has been investigated, including Ti, V, Cr,

Fe, Co, Mn, Cu, Zn, Cd, Sn, Al, B, Mg, Ga, Ca, Na,. . . . Research is now oriented on multiple substitution,with each element bringing some peculiar advantage

on reversibility, fading or thermal stability for safety.Some material can be produced now on an industrialscale, and utilisation in commercial cells can be antici-

pated soon.

3.3. LiMn2O4 and derivatives

For many years, the three-dimensional spinelLiMn2O4 has been the object of intense worldwideresearch to improve its behaviour (see for exampleRef. [52]). This is motivated by four advantages of this

material: a potential lower cost of Mn than Ni or Co,a larger thermal stability domain especially when over-charged, a higher discharge voltage useful for telecom

appliance and a more friendly impact on environment.However, in spite of significant improvements from thebeginning of this research work, it still suers from

some major diculties: first of all a low specific ca-pacity associated with a low density compared to othercandidates, secondly a potentially lower power than

Fig. 7. DSC measurements on LiNiO2, LiCoO2, LiMn2O4 compared to new multi doped LiNi(1M)MMO2 material with improvedsafety (M=0.25). Scanning rate is 108C/min. Electrolyte is PC/EC/DMC (1/1/3)+LiPF6 (1 M).


the layered materials (LiNiO2, LiCoO2), finally fadingand losses on storage are very high, especially with

increasing temperature.

Capacity improvement of cells using LiMn2O4 activematerial may be improved through pre-reduction

methods. These procedures aim at compensating the ir-reversible losses of the negative electrode, so increasing

the overall cell energy. Dierent methods have been

proposed including reaction with LiI in organic solventat 808C [53] or recently by reaction with n-buthyl-lithium [54]. However, these treatments do not improvecycling performance.

A lot of work was done in the early 90s to improve

electrochemical performances of the spinel. Capacityfading has been attributed to the JahnTeller eect

[55], structural instability at high potentials [56] or to

manganese dissolution [57]. Research was mainly dedi-cated to substitution for manganese by other elements

like iron [58,59], cobalt [55,6062], nickel [58,59] ormore exotic ones like magnesium, titanium, silver, cop-

per and some others [58,63]. Generally, all these ma-

terials exhibit lower performance than the pristinespinel in terms of capacity (100110 A h/kg), although

fading improvement is observed with cobalt and mag-nesium [63]. Improvement of fading by cobalt substi-

tution was confirmed recently by Arora et al., and

both the amount and rate of capacity loss aredecreased [64]. These results are explained by a specific

surface diminution and higher crystal size for one part,and easier lithium charge transfer reaction and lithium

diusion into the structure for a second part.

A main breakthrough in this field are the over-lithiated phases of general formulation

Li(1+d )Mn(2d )O4 [63], presenting strongly reducedfading, albeit with some reduction in capacity. This is

illustrated in Fig. 8, with comparison to typical beha-viour of LiCoO2 industrial materials. It shows clearly

the lower capacity of manganese compounds and the

reduction of fading at 608C thanks to over lithiation ofthe material, with lower capacities as the ratio of Li/

Mn increases.

Elevated temperature is a more crucial problem forthe LiMn2O4 positive material. Mn

3+ dismutation and

dissolution of the Mn2+ produced, is a severe problemof the spinel. It appears to contribute greatly to the

occurrence of irreversible losses during storage at elev-

ated temperature: for which partial improvement isobtained by using low surface area materials (

Industrial materials are beginning to be available withreduced SSA and lithium-rich compositions leading to

improved performance in terms of capacity fading.However, fading, particularly at elevated temperature,is still far worse than that observed with nickel or

cobalt-rich materials. Despite this, a range of lithium-ion cells using LiMn2O4 spinel as positive active ma-terial are now available from Moli Energy Limited for

portable equipment.

3.4. Other 4 V materials

Two other materials have been mainly studied toreplace the three main candidates: LiMnO2 and

LiFeO2.Orthorhombic LiMnO2 may be an excellent material

for lithium-ion batteries [66], even better than

LiMn2O4 because its higher Li/Mn ratio: theoreticalcapacity is close to LiNiO2 and LiCoO2 ones (285 Ah/kg). Several laboratories have been studying itsstructural or electrochemical properties [6773].

Besides the optimisation of the synthesis process, amain problem is the gradual structural transformationof the material during cycling. After few cycles, the

material behaves very much like LiMn2O4 spinel: thecapacity is split in two dierent electrochemical mech-anisms at 3 and 4 V, respectively [72,73]. However the

cycling behaviour is much better than for LiMn2O4,when cycling on both voltage plateaus. This partitionof the capacity in two voltage plateaus of 1 V dier-ence makes this material useless in practical cells.

The electrochemical performances of both orthor-hombic and ramsdellite LiFeO2 phases was describedin a few papers [7476]. Properties were studied up to

4.5 V, some authors claiming electrochemical reversibleactivity around 4 V. However, it seems rather that irre-versible reactions occur at high potential: main pro-

blem seems the instability of Fe4+ species inLi1xFeO2 with the electrolyte. Reversible intercalationmay be obtained only at about 3 V, as evidenced in a

recent work to be published on these materials [77,78].

3.5. Towards 5 V

A recent trend in the positive material field is theappearance of a new family of materials having anaverage working voltage of 5 V or so. First studied

were the inverse spinel vanadates like LiNiVO4[79].These are also generally spinel materials close toLiMn2O4 with levels of substitution up to 50% with el-

ements like copper [80,81], cobalt [82,83], nickel [59,84]iron [85] or chromium [86]. Specific capacities are inthe range of 80120 A h/kg maximum at the moment.

Explanation of the very high working voltage is stillnot clear. According to Ohzuku et al. [87] this is aresult of the very high solid state redox potential of

the substituting cations in the compact crystal field ofthe spinel framework structure. Redox potentials

would rely between 4.8 and 5 V for the metals alreadylisted plus nickel and zinc in spinel of compositionLiMe1/2Mn3/2O4.

This new field of research may be very promisingproviding stable electrolytes may be found at thesevery high potentials. Fading behaviour and also safety

of such materials is still an open question.

4. The negative material

As opposed to the study of insertion compounds forpositive electrodes, such materials for the negativewere much less investigated before the emergence of Li

ion. One must recognise that the exceptional behaviourof carbon as an insertion material of lithium in organicsolvents is quite surprising: few battery specialists

would have predicted that the necessary passivationlayer built on the (large) surface area of the lithiatedcarbon would have sucient stability and reversibility

Fig. 9. OCV of fully lithiated carbons (short cut with lithium

counter electrode 48 h) as a function of discharge capacity.

(a) and (b) are the same figures at dierent scales, to highlight

the usable range (1b). Electrolyte: EC/DMC 1 MliPF6.


SamuelHighlight

to insure a high cycle life of thousands of cycles with-out irreversible lithium corrosion, as we can foresee

today.As mentioned above, the first attempts to use graph-

ites as the negative host structure for lithium ion failed

because of electrode disintegration. Only intercalationvia solid polymer electrolyte at high temperature wasreported as successful [13]. The situation changed with

the finding that poorly crystalline carbons are less sen-sitive to that electrolyte decomposition. The feasibilitywas demonstrated but with modest capacities com-

pared to that expected with graphite [88]. Sony was thefirst company to achieve a commercial battery basedon such a non-crystalline carbon negative [1]. Itappeared later from patent literature that several

Japanese battery makers had been working on thatfield few years before [2]. Crystalline carbon materialsthen regained interest when LiC6 stoichiometry was

actually achieved with a careful design of electrolytecomposition [8991] mainly based on ethylene carbon-ate (EC).

4.1. The carbon properties

4.1.1. Specific energyThe basic requirement is a high quantity of revers-

ible lithium ion inserted per unit of volume or mass, at

a potential range close to that of metallic lithium. Thisproperty appears to be very dependent on the carboncrystalline structure (Fig. 9):

4.1.1.1. Crystalline carbons. The mechanism of lithiumintercalation in crystalline carbons is well known,

thanks to X-ray spectroscopy methods [90,91]. It isvery similar to that proposed for vapor phase interca-lation, as it proceeds through well-identified stages,apparent as potential plateaus on the O.C.V. curve

(Fig. 9). LiC6 (372 mA h/g) in the 0300 mV range vs.a Li/Li+ reference electrode is achieved only for car-bons with a low degree of turbostatic disorder (inter-

layer space d002 < 0.336 nm), generally referred asgraphites. For graphitised carbons, higher values ofinterlayer space result from the presence of structural

defects that decreases the capacity. Several theorieshave been proposed to account for this capacitydecrease [9294].

4.1.1.2. Non crystalline carbons. For this kind of car-bon that exhibits large undefined peaks on X-ray spec-tra, two dierent qualitative behaviours are observed:

The coke type behaviour shows no evidence of sta-ging and a sloppy evolution of potential as a functionof Li content. For carbons synthesised at low tempera-

ture, an extra capacity is discharged with large hyster-esis at high potential (>1 V/Li), that can reach valuesas high as 1000 mA h/g [95]. However, this is not of

practical interest in a battery if high average voltage is

required. This behaviour has been associated with co-valent Li bonding in large hydrogen content carbons[96], with the presence of microcavities [93] and the

occurrence of Li2 molecules [97].The hard carbon behaviour shows an additional

pseudo potential plateau (Fig. 9) with no hysteresis at

high lithium content [98]. There is still some contro-versy about the actual mechanism for such a behaviour[99101]. From 7Li RMN measurements, the lithium

absorbed at high lithium content do not present a met-allic character [102] and seems to result in a schematicway from dense absorption of Li in microcavities.Therefore high porosity of this structure is a basic

requirement, and the volumetric energy density is con-sequently limited. A concern remains about the electro-chemical behaviour at high charging rate, as a large

part of the capacity is obtained at potential very closeto that of metallic lithium (Fig. 10). When polarisationincreases at high current density, it appears dicult to

ensure lithium ion absorption throughout the electrodethickness without metallic lithium deposition on theouter electrode surface.

4.1.2. Reversibility

4.1.2.1. Passivation losses. All carbon types experienceirreversible side reactions during the first electrochemi-cal absorption of lithium ions. A generally recognisedsource of irreversibility is the electrolyte instability at

low potential yielding insoluble products [13,103,104].As no thermodynamically stable electrolyte of interesthave been found up to now, the quality of the resulting

passivating layer is fundamental for the further interca-lation of Li ion and explains the large work involvedfor its characterisation by dierent techniques [105

108]. A major contribution came from the work ofAurbachs team [107,109,110] mainly based on FTIRtechnique. This explained why the cyclic carbonates

Fig. 10. End of charge of carbon electrodes at a rate of 20

mA/g of carbon. Electrolyte: EC/DMC 1 M LiPF6.


like propylene carbonate or ethylene carbonate were

the best-suited solvents, as they yield double lithium

alkyl carbonates with a good passivating ability. The

exceptional physical properties of the layer formed,

itself greatly dependent on the electrolyte composition,

and the small variations of molar volume between the

charged and discharged states, are actually the key

points which allow the Li ion battery to exist.

The carbon characteristic which should be linked to

this phenomenon is the electrochemically active surface

area, and a relationship with the amount of faradic

losses has indeed been reported [89,111,112], in the

absence of any additional source of irreversibility (Fig.

11).

For this purpose, materials having special mor-

phology like carbon spheres grown from mesophase or

fibers [92,113] are attractive for surface area optimis-

ation.

4.1.2.2. Exfoliation. With crystalline carbons, a large

irreversible capacity loss can occur during the firstintercalation step, regardless of their surface area.

Exfoliation of graphene layers can explain such a lowfaradic eciency [89]. It results from intercalation of

solvated lithium ion followed by gas release in the car-bon structure [11], causing the exfoliation to occur and

resulting in newly created surface area needing extrapassivation. This has been confirmed by dierent tech-

niques [114116].

As discussed earlier, crystalline materials are highlydesirable to achieve high energy density, but they had

remained discarded because of this exfoliation occur-rence. Improvement of their electrochemical behaviour

allowing their utilisation in actual batteries has beenthe subject of many studies. Propylene carbonate (PC),

a solvent otherwise interesting for its physical proper-ties, has been pointed as the main culprit in the exfo-

liation of crystalline carbons, whereas ethylenecarbonate EC or other carbonates would prevent it

[89,90]. Although graphites can be exfoliated even inEC based electrolyte without PC [112], it is true that

the sensitivity of crystalline carbon to PC is markedlyhigher (Fig. 12). The dierence of behaviour of such

close molecules like PC and EC is not yet fully under-stood.

Another way to reduce the risks of exfoliation is tochoose graphite grades with a high content of rhombo-

hedral phase [117]. This phase is generally introducedin commercial samples from the normal hexagonal

structure by a grinding operation. High rhombohedralphase content are more resistant to exfoliation and can

withstand large amount of propylene carbonate [113](Fig. 13).

A third method eective in hindering crystalline car-

bon exfoliation consists of the addition to the electro-lyte compounds able to passivate the carbon at high

Fig. 11. Irreversible losses at the first cycle of teflon bonded

electrodes, at 20 mA/g, in the range 02 V. EC based electro-

lyte (EC/DMC LiTFSI 1 M), as a function of specific surface

area (BET).

Fig. 12. Influence of PC on graphite exfoliation: First cycle

(20 mA/g) of synthetic graphite teflon bonded electrode. EC

based=EC/DMC 1 M LiPF6, PC based=PC/EC/DMC (1/1/

3), 1 M LiPF6.

Fig. 13. Irreversible faradic losses at the first cycle of teflon-

binded graphite electrodes, at 20 mA/g in the range 0 to 2 V.

The losses are expressed per m2 of carbon material (estimated

from the BET surface area) to eliminates the dierences due

to passivation. Electrolytes: EC based=EC/DMC 1 M LiPF6,

PC based=PC/EC/DMC (1/1/3), 1 M LiPF6.


potential, prior to solvated lithium intercalation. SO2[118], vinylene carbonate [119] and chloroethylene car-

bonate [120] have revealed eciency in that purpose.

4.2. Non-carbon anodes

As mentioned above, the use of insertion materialsother than carbons was suggested quite a long timeago. Metal oxides like WO2 or Fe203 [121], and more

recently Li4Ti5O12 [122], were proposed for rockingchair batteries, but they present a high average voltageversus metallic lithium and limited reversible capacity,

resulting in low energy density for complete cells (seeSection 5). The problem was similar with metal sulfidesthat decompose to metal and lithium sulfide at low po-

tential [123]. Conducting polymers like polyacetyleneare stable at low potential, but present low volumetriccapacity for lithium doping [124].A new class of materials, based on amorphous ox-

ides, is now being investigated. This originates fromFuji Photo Film company, which announced the useof tin-based amorphous oxides in a commercial pro-

duct [125]. Controversy remains concerning the exactmechanism [126,127], but it seems that, at least for thecrystalline forms, the functioning is based on the for-

mation of metal clusters which further alloy withlithium. Beside the fact that reduction to metal fromoxide is an irreversible reaction causing high capacityloss, this principle rises questions about its sensitivity

to temperature and charging condition [128]. Indeed,the commercial launching of batteries with such anegative material has been delayed.

The mention of metal cluster occurrence in the for-mer systems revived some interest in lithium alloyswith special characteristics, as for example nanometric-

sized particles [129].Metal vanadates have also been investigated at low

potential, and although the mechanism proposed is

dierent, they share with tin based oxides high valuesof both irreversible and reversible capacities [130].

Finally, some promising work has been publishedconcerning lithiated metal nitrides [131,132] with bothhigh capacity (up to 800 mA h/g) and low average vol-tage (0.5 V vs. Li). The fact that they are available

only in a lithiated (=charged) state rules out problemsof irreversibility on first charge encountered with othermaterials, but on the other hand eliminates conven-

tional positive lithiated (=discharged) metal oxideswhich allow high voltage. Indeed, these highly oxidiz-ing positive materials cannot be handled in their

charged state for cell manufacturing.

4.3. Trends

The use of carbon seems to be well established, atleast for the medium term. Within this class of pro-ducts, things are still moving rapidly. In fact, the

choice of a particular grade of carbon results fromcompromises, including electrode processing, and es-pecially the cost, because of very tough competition.

After the initial interest in non-crystalline carbons eventhough they could be further improved, the generaltrend of battery makers is to use crystalline carbons

with carefully designed electrolyte composition.Because of their low price and higher capacity, naturalor synthetic graphites seem still to be preferred bysome manufacturers, whereas others use variable

amounts of spherical or fiber shape materials.

5. Impact of the main properties of insertion compounds

on battery characteristics

While battery designers can rapidly calculate theimpact of the introduction of a new material in a par-ticular technology, many scientists often lack the tools

Table 1

Average values for main cell design parameters

Constant parameters (unless used as variables)

Negative mat. Specific capacity 350 A h/kg

Negative material specific gravity 2.2 g/cm3

Positive mat. Specific capacity 140 A h/kg

Positive material specific gravity 5 g/cm3

Negative excess over positive 10%

Negative first charge eciency 90%

Electrode porosity 30%

Separator thickness 25 mmCollectors total thickness 30 mmTotal cell stack thickness (2 electrodes coated both sides, 2 separators) 500 mmAverage cell working voltage during complete discharge at medium rate. 3.5 V


to evaluate the characteristics of actual cells using that

material. The purpose of this section is to give some

figures, which would help in this evaluation.

The easiest way is to calculate the volume and

weight of the complete cell stack, including the active

materials, conductive and binder additives, current col-

lectors, separator and electrolyte.

Then construction derating factors of 0.8 for the

Fig. 14. Influence of the specific capacity of materials on complete cell specific energy.

Fig. 15. Influence of the volumetric capacity of the materials on the cell energy density.


weight and 0.75 for the volume are applied to deter-mine actual cell characteristics (large batteries).The main parameters used in these calculations can

be considered as an optimised Li ion cells using con-ventional separators, assuming that the negative iscarbon, as described in Table 1. This design would

provide an energy density of 400 W h/l and a specificenergy of 160 W h/kg. The hybrid or plastic poly-mer technology, using roughly the same type of elec-

trodes, would dier mainly from these numbers bythe thickness of the electrolyte-separator, presentlyabout 2 to 3 times thicker than the conventional

ones. This would give, for a 60 m thick polymerseparator, comparative values of 335 W h/l, and 145W h/kg. Both construction factors should beincreased to close to 0.9 to come back to the same

final values as conventional technology. This technol-ogy is especially more favorable for small thin bat-teries (

5.4. Physical properties

The usual electrode manufacturing process consists

of coating thin metallic foils with an ink containing

the active material dispersed in an appropriate liquid

medium, including a binder and eventually carbon con-

ductive agent. Up to now, the most used binder has

been PVDF, dissolved in NMP, but other non-fluori-

nated binders may be used, dispersed in water. After

drying, the electrode is laminated to the desired thick-

ness and porosity. The physical properties of the active

materials, including the shape and size of particles and

the taped density (apparent density of the powder after

taping), will also have a significant impact on the abil-

ity of the electrode to be compressed, and consequently

on the achievement of low porosity and good conduc-

tivity. Good adhesion to the collector and coating

robustness are also very dependent on the powder

properties. Each battery manufacturer will have its

own requested specifications, depending on its elec-

trode process. However, the general trends are low sur-

face area dense particles (in the order of a few m2/g or

less), in the range of 530 mm sizes, having a hightaped density.

Fig. 17. Influence of electrodes porosity on the cell energy density and specific energy.

Fig. 18. Cell energy density as a function of capacity density (A h/l) of non-carbon negative material, for dierent first charge e-

ciency.


As an example, Fig. 17 shows the evolution of thecell energy density with the electrodes porosity, assum-

ing that negative and positive are the same.

5.5. Properties of non-carbon anodes

The nano-dispersed alloy-forming metals, like thoseoriginating from amorphous oxides, have recently beenextensively investigated since the introduction of this

new class of negative by Fuji-film in Japan. However,the usually large irreversible capacity consumption

during the first charge to reduce the oxides to metals

and build a passivating layer reduces their interest con-

siderably (see Section 4.2). Fig. 18 shows how high this

initial charge eciency (as first charge eciency), must

be to obtain a sucient energy density.

In this model, the capacity of the negative is

expressed as capacity density, in A h/l. 6 g/cm3 as

been taken as the negative material specific gravity,

and the calculations are made for specific capacities

from 300 to 750 A h/kg. The average voltage is sup-

posed to be 0.3 V lower than graphite, i.e. 3.2 V.

Fig. 19. Volume of Portable cells produced world-wide (from H. Takeshita, Nomura Research Institute 1998 report).

Fig. 20. Portable cell energy (MW h) produced/year (from H. Takeshita, NRI 1998 report).


6. Applications and market of Li ion batteries

The considerable success of small Li ion batteries is

largely due to the very rapid growth of cellular phonesand portable computers. The high energy density, very

high specific energy and high voltage of this batterytype make it very attractive.Fig. 19 shows the volume of Li ion cells produced

between 1993 and 1999 (projected), compared with theother competitive new product, NiMH. Quoted in W hin Fig. 20 (the average energy of a Li ion cell is about

3.7 W h with a tendency to decrease), one can see thatLi ion and NiMH have now reached about the same

production level.Due to the higher selling price of Li ion, its turnover

is now the most important of the small rechargeable

cells representing about 40% of the total, as shown inFig. 21. The unit cell prices have drastically decreasedfor both NiMH and Li ion, and at the same time the

size of the cells is diminishing. There is also an increas-ing demand for prismatic shape vs. cylindrical (Fig.22). From market experts, the level of manufacturing

Fig. 21. Sale value of portbale cells (from H. Takeshita, NRI 1998 report).

Fig. 22. Evolution of Li ion cell type, percentage between cylindrical and prismatic shape (from H. Takeshita, NRI 1998 report).


capability worldwide is close to exceeding the demandof the portable market.

The next expected evolution, which could changethis situation is the introduction of polymer Li ion bat-teries, where the conventional polypropylene/polyethy-

lene microporous separator is replaced by a PVDF-based polymer swelled by electrolyte, sticking togetherthe two thin electrodes. Presently under development

or pre-industrialisation, these cells will oer the possi-bility of making very attractive thin cells for small por-table devices, providing the required power is

available.Beside small portable electronic devices, Li ion tech-

nology is also very suitable for large batteries, in appli-cation where energy density or specific energy is of

prime importance. Electric vehicles and satellites arepresently the most representative applications.Excellent specific power, which can reach values as

high as 1500 W/kg with still more than 60 W h/kgspecific energy is an interesting additional feature ofthis technology, mainly related to thin electrodes tech-

nology. Thanks to these outstanding properties, the Liion concept is expected to be applied in a near term tomany other utilisations.

7. Conclusions

The future of Li ion batteries appears to be verybright, when considering their outstanding perform-ance. Insertion materials, especially carbon electrodes,

have been the key of success for this new type ofelectrochemical power sources, and these compoundswill be improved again in the coming years A lot ofnew applications will use this battery system in a

near future, with both smaller and larger batteriesthan today. However, a very wide spreading of thistechnology is linked to a drastic cost reduction and

improvement of safety on abuse conditions. Each ofthese stakes can be addressed not only by design con-sideration, but also by working on new materials, es-

pecially on the positive electrode. Due to the infinitenumber of solutions oered by solid state chemistryin building mixed materials, very promising resultsare already obtained and further discoveries can be

expected.

References

[1] T. Nagaura, K. Tozawa, Prog. Batt. Solar Cells 9

(1990) 209.

[2] Asahi Kasei, JP 1989 293 (priority 1985), US Patent

4,668,595, 1987.

[3] J.E. Chilton Jr., G.M. Cook, in: Abstract, ECS Fall

Meeting, Boston, 1962, pp. 9091.

[4] D. Herbert and J. Ulam, US Patent 3,043,896, 1962.

[5] J.P. Gabano, G. Gerbier, J.F. Laurent, Proc. 23rd

Power Sources Conf., Atlantic City, 1969.

[6] M.S. Whittingham, Science 192 (1976) 1126.

[7] J.L. Godman, R.M. Mank, J.H. Young, V.R. Koch, J.

Electrochem. Soc. 127 (1980) 1461.

[8] W.A. Adams, G.J. Donaldson, J.A.R. Stiles, in: J.

Thompson (Ed.), Power Sources 10, 1984.

[9] A.N. Dey, J. Electrochem. Soc. 118 (1971) 1547.

[10] A. Herold, Bull. Soc. Chim 187 (1955) 999.

[11] J.O. Besenhard, Carbon 14 (2) (1976) 93138.

[12] M. Armand, Ph.D. thesis, Grenoble, 1978, and French

Patent 78 32977, 1978.

[13] R. Yazami, P.H. Touzain, J. Power Sources 9 (1983)

365371 (also Ext. Abstract fo 1st International

Meeting on Lithium Batteries, Roma, 1982).

[14] S. Basu, US Patent 4,304,825, 1981.

[15] S. Basu, US Patent 4,423,125, 1983.

[16] M. Lazzari and B. Scrosati, J. Electrochem. Soc., Brief

Communication, March 1980.

[17] M. Armand, in: D.W. Murphy, J. Broadhead, B.C.H.

Steeles (Eds.), Materials for Advanced Batteries,

Plenum, New York, 1980.

[18] M.S. Whittingham, US Pat, 4,009,052, 1973.

[19] M.S. Whittingham, J. Electrochem. Soc. 123 (1976)

315.

[20] M. Anderman, J.T. Lundquist, J. Electrochem. Soc.,

Technical Notes, May, 1988.

[21] K.M. Abraham, J. Power Sources 7 (1982) 143.

[22] A. Lemehaute, G. Ouvrard, R. Brec, J. Rouxel, Mater.

Res. Bull. 12 (1977) 741.

[23] J. Broadhead, Proc. 3rd Annu. Battery Cong. on

Applications and Advances, Long Beach, CA, 1988.

[24] L. Campanella, G. Pistoia, J. Electrochem. Soc. 118

(1971) 1905.

[25] J.O. Besenhard, R. Shollhorn, J. Electrochem. Soc. 124

(1977) 968.

[26] D.W. Murphy, P.A. Christian, F.J. DiSalvo, J.N.

Carides, J. Electrochem. Soc. 126 (1979) 497.

[27] K. Mizushima, P.C. Jones, P.J. Wiseman, J.B.

Goodenough, Mater. Res. Bull 17 (1980) 785.

[28] E. Plichta, M. Salomon, S. Slane, M. Uchiyama, J.

Power Sources 21 (1987) 2531.

[29] M. Broussely, F. Perton, J. Labat, R.J. Staniewicz, A.

Romero, J. Power Sources 4344 (1993) 6574.

[30] J.R. Dahn, E.W. Fuller, M. Obrovac, U. von Sacken,

Solid State Ionics 69 (1994) 265.

[31] Ph. Biensan, B. Simon, J.P. Pere`s, A. de Guibert, M.

Broussely, J.M. Bodet, F. Perton, Extended Abstracts,

PIII-84, IMLB9, Edinburgh, (1998), J. Power Sources,

1999 in press.

[32] T. Ohzuku, A. Ueda, J. Electrochem. Soc. 141 (1994)

2972.

[33] J.N. Reimers, J.R. Dahn, J. Electrochem. Soc. 139

(1992) 2091.

[34] K. Matsumoto, T. Tsujimura and K. Takeishi,

Extended Abstracts, PII-56, IMLB9, Edinburgh, (1998)

J. Power Sources, 1999, in press.

[35] C. Delmas, I. Saadoune, Solid State Ionics 5356

(1992) 370.

[36] I. Saadoune, Ph.D. thesis, Bordeaux University, 1992.


[37] R.J. Gummow, M.M. Thackeray, Solid State Ionics

5356 (1992) 681.

[38] R. Alcantara, P. Lavela, J.L. Tirado, R. Stoyanova,

E. Zhecheva, J. Electrochem. Soc. 145 (1998) 730.

[39] R. Alcantara, P. Lavela, J.L. Tirado, C. Perez-Vicente,

J.C. Jumas and J. Olivier-Fourcade, Extended

Abstracts, PII-52, IMLB9, Edinburgh, (1998), J. Power

Sources, 1999, in press.

[40] G. Ceder, Y.M. Chiang, D.R. Sadoway, M.K.

Aydinol, Y.I. Jang, B. Huang, Nature 392 (1998)

694.

[41] Y.M. Chiang, D.R. Sadoway, Y. Jang, B. Huang and

H. Wang, PII-67, IMLB9, Edinburgh, (1998), J. Power

Sources, 1999, in press.

[42] K. Honbo, Y. Muranaka, M. Yoshikawa, in: 39th

Battery Symposium in Japan, Senda, 1998, p. 311

(Abstract 3C10).

[43] J.N. Reimers, W. Li, J.R. Dahn, Phys. Rev. B 47

(1993) 8486.

[44] A. Rougier, P. Graveau, C. Delmas, J. Electrochem.

Soc. 143 (1996) 1168.

[45] J.P. Pere`s, Ph.D. thesis, Bordeaux University, 1996.

[46] C. Delmas, J.P. Pere`s, A. Rougier, A. Demourgues, F.

Weill, A. Chadwick, M. Broussely, F. Perton, Ph.

Biensan, P. Willmann, J. Power Sources 54 (1995)

329.

[47] C. Delmas, J.P. Pere`s, C. Louchet, F. Weill, F. Perton,

Ph. Biensan, A. de Guibert and P. Willmann, PII-39,

IMLB9, Edinburgh, (1998), J. Power Sources, 1999, in

press.

[48] H. Watanabe, T. Sunugawa, H. Fujimoto, T. Nohma,

K. Nishio, Abstract of the 1997 Joint International

Meeting ECS-ISE, Paris, vol. 97-2, 1997, p. 256.

[49] T. Ohzuku, T. Yanagawa, M. Kouguchi, J.

Electrochem. Soc 142 (1995) 4033.

[50] Y. Gao and M.V. Yakovleva, PII-5, IMLB9,

Edinburgh, (1998), J. Power Sources, 1999, in press.

[51] Y. Gao, M.V. Yakovleva, W.B. Ebner, Electrochem.

Solid State Lett. 1 (3) (1998) 117.

[52] M.M. Thackeray, M.F. Mansuetto, J.B. Bates, J.

Power Sources 68 (1997) 153158.

[53] J.M. Tarascon, D. Guyomard, J. Electrochem. Soc.

138 (1991) 807.

[54] D. Peramunage, K.M. Abraham, J. Electrochem. Soc.

145 (1998) 1131.

[55] L. Guohua, H. Ikuta, T. Uchida, M. Wakihara, J.


[56] V. Manev, B. Banov, A. Momchiler, A. Nassalevska,

J. Power Sources 57 (1995) 99.

[57] H. Kanoh, Q. Feng, T. Hirotsu, K. Ooi, J.


[58] J.M. Tarascon, E. Wang, F.K. Shokoohi, W.R. Mc

Kinnon, S. Colson, J. Electrochem Soc. 138 (1991)

2859.

[59] K. Amine, H. Tukamoto, H. Yasuda, Y. Fujita, J.

Power Sources 68 (1997) 604608.

[60] R. Bittihn, R. Herr, D. Hoge, J. Power Sources 43

(1993) 223.

[61] W. Liu, K. Kowal, D. Louca, T. Egami, G.C.

Farrington, ECS Spring Meeting, Vol. 50, 1996, p. 60

Ext. Abstract.

[62] A.R. Armstrong, P.G. Bruce, Nature 381 (1996) 499.

[63] R.J. Gummow, A. de Kock, M.M. Thackeray, Solid

State Ionics 69 (1994) 59.

[64] P. Arora, B.N. Popov, R.E. White, J. Electrochem.

Soc. 145 (1998) 807.

[65] G.G. Amatucci, C.N. Schmutz, A. Blyr, C. Sigala,

A.S. Gozdz, D. Larcher, J.M. Tarascon, J. Power

Sources 69 (1997) 11.

[66] Saft, US patent 5 561 006, 1994.

[67] R. Hoppe, G. Bratchel, M. Jansen, Z. Anorg. Allg.

Chem 417 (1975) 1.

[68] T. Ohzuku, A. Ueda, T. Hirai, Chem. Express 7 (1992)

193.

[69] R.J. Gummow, D.C. Liles, M.M. Thackeray, Mater.

Res. Bul. 28 (1993) 1249.

[70] J.N. Reimers, E.W. Fuller, E. Rossen, J.R. Dahn, J.


[71] I.J. Davidson, R.S. McMillan, J.J. Muray, J.E.

Greedan, J. Power Sources 54 (1995) 232.

[72] L. Crognennec, P. Deniard, R. Brec, A. Lecerf, J.

Mater. Chem. 7 (1997) 511.

[73] L. Crognennec, P. Deniard, R. Brec, P. Biensan, M.

Broussely, Solid State Ionics 89 (1996) 127.

[74] R. Kanno, T. Shirane, Y. Inaba, Y. Kawamoto, J.

power Sources 68 (1997) 145152.

[75] Y. Sakurai, H. Arai, S. Okada, J. Yamaki, J. Power

Sources 68 (1997) 711715.

[76] R. Kanno, T. Shirane, Y. Kawamoto, Y. Takeda, M.

Takano, M. Ohashi, Y. Yamagushi, J. Electrochem.

Soc. 143 (1996) 2435.

[77] L. Bordet, P. Deniard, A. Lecerf, P. Biensan, R. Brec,

Solid State Ionics, in preparation.

[78] L. Bordet-Le Guenne, P. Deniard, A. Lecerf, P.

Biensan, C. Siret, L. Fourne`s, R. Brec, J. Mater.

Chem., in preparation.

[79] G.T. Fey, W. Li, J.R. Dahn, J. Electrochem. Soc 141

(1994) 2279.

[80] Y. Ein-Eli, W.F. Howard, S.H. Lu, S. Mukerjee, J.

McBreen, J.T. Vaughey, M.M. Thackeray, J.


[81] Y. Ein-Eli, W.F. Howard, S.H. Lu, S. Mukerjee, J.

McBreen, J.T. Vaughey, M.M. Thackeray, J.


[82] H. Kawai, M. Nabata, H. Tukamoto, A.R. West,

Electrochem. Solid State Lett. 1 (1998) 212.

[83] H. Kawai, M. Nabata, H. Tukamoto, A.R. West, J.

Mater. Chem. 8 (1998) 837.

[84] Q. Zhong, A. Bonakdarpour, M. Zhang, Y. Gao, J.R.

Dahn, J. Electrochem. Soc 144 (1997) 205.

[85] Y.M. Todorov, M. Yoshio, in: 39th Battery

Symposium in Japan, Senda, 1998, p. 273 (Abstract

2C14).

[86] N. Kumada, M. Yoshio, in: 39th Battery Symposium

in Japan, Senda, 1998, p. 275 (Abstract 2C15).

[87] T. Ohzuku, S. Takeda, M. Iwanaga, T. Aoki, in: 39th

Battery Symposium in Japan, Senda, 1998, p. 271

(Abstract 2C13).

[88] R. Kanno, Y. Takeda, T. Ichikawa, K. Nakanishi, O.

Yamamoto, J. Power Sources 26 (1989) 534.

[89] R. Fong, U. Von Sacken, J.R. Dahn, J. Electrochem.

Soc 137 (1990) 2009.


[90] D. Billaud, F.X. Henry, P. Willmann, Mat. Res. Bull.

28 (1993) 477.

[91] T. Ozhuku, Y. Iwakoshi, R. Sawai, J. Electrochem.

Soc 140 (1993) 2496.

[92] A. Mabuchi, H. Fujimoto, K. Tokumitsu, T. Kasuh, J.


[93] S. Flandrois, A. Fevrier-Bouvier, K. Guerin, B. Simon,

P. Biensan, Mol. Crystal Liquid Crystals 310 (1998)

389.

[94] J.R. Dahn, A.K. Sleight, H. Shi, J.N. Reimers, Q.

Zhong, B.M. Way, Electrochem. Acta 38 (1993)

1179.

[95] A. Mabuchi, H. Fujimoto, K. Tokumitsu, T. Kasuh, J.


[96] T. Zheng, Y. Liu, E.W. Fuller, S. Tseng, U. von

Sacken, J.R. Dahn, J. Electrochem. Soc 142 (1995)

2581.

[97] K. Sato, M. Noguchi, A. Demachi, N. Oki, M. Endo,

Science 264 (1994) 556.

[98] Omaru, A., Azuma, H., Aoki, M., Kita, A., Nishi, Y.,

Abstract 25, p. 24, The Electrochemical Society

Extended Abstract, vol. 92-2, Toronto, ON, Canada,

Octobre 1116.

[99] N. Sonobe, M. Ishikawa, T. Iwasaki, in: 35th Battery

Symposium in Japan, Nagoya, Japan, Nov. 1416

1994, Extended Abstracts, 1994, p. 49.

[100] T. Zheng, Y. Liu, E.W. Fuller, S. Tseng, U. von

Sacken, J.R. Dahn, J. Electrochem. Soc. 142 (1995)

2581.

[101] P. Zhou, P. Papanek, C. Bindra, R. Lee, J.E. Fischer,

J. Power Sources 68 (1997) 296.

[102] K. Tatsumi, T. Kawamura, S. Higuchi, T. Hosotubo,

H. Nakajima, Y. Sawada, J. Power, Sources 68 (1997)

263.

[103] Z.X. Shu, R.S. MacMillan, J.J. Murray, J.


[104] B. Simon, J.P. Boeuve, M. Broussely, J. Power Sources

4344 (1993) 65.

[105] K. Takei, K. Kumai, Y. Kabayashi, H. Miyashiro, T.

Iwahori, T. Uwai, H. Ue, J. Power Sources 54 (1995)

171.

[106] A.C. Chu, J.Y. Josefowicz, G.C. Farrington, J.


[107] D. Aurbach, A. Zaban, Y. Ein-Eli, I. Weissman, O.

Chusid, B. Markowsky, M. Levi, E. Levi, A.

Schechter, E. Granot, J. Power, Sources 68 (1997) 91.

[108] N. Takami, A. Satoh, M. Hara, T. Ohsaki, J.


[109] D. Aurbach, B. Markovsky, A. Shetcher, Y. Ein-Eli, J.


[110] D. Aurbach, Y. Ein Eli, O. Chusid, Y. Carmeli, M.

Babai, H. Yamin, J. Electrochem. Soc 141 (1994) 603.

[111] P. Schoderbock, H.P. Boehm, Mat. Sci. Forum 9193

(1992) 683.

[112] B. Simon, S. Flandrois, A. Fevrier-Bouvier, P. Biensan,

Mol. Crystal Liquid Crystals 310 (1998) 333.

[113] N. Takami, A. Satoh, M. Hara, T. Ohsaki, J.


[114] D. Aurbach, Y. Ein-Eli, J. Electrochem. Soc. 142

(1995) 1746.

[115] B. Simon, S. Flandrois, K. Guerin, A. Fevrier Bouvier,

P. Biensan, Proceedings of IMLB 9 Edimbourgh 1998,

Tues, poster No. 55.

[116] M. Inaba, Z. Siroma, A. Funakubi, Z. Ogumi,

Langmuir, 12 (1996).

[117] S. Flandrois, A. Fevrier., P. Biensan, B. Simon, US

pat. 5554462.

[118] Y. Ein Eli, S.R. Thomas, V.R. Koch, J. Electrochem.

Soc 143 (1996) L195.

[119] B. Simon, J.P. Bpeuve, B. Spigai, M. Broussely, ECS

Meeting abstracts vol. 97-2, 184 Paris september 1997.

[120] Z.X. Shu, R.S. McMillan, J.J. Murray, I.J. Anderson,

J. Electrochem. Soc 143 (1996) 2230.

[121] B. Di Pietro, M. Patriarca, B. Scrosati, J. Power

Sources 8 (1982) 289.

[122] T. Ozhuku, A. Ueda, N. Yamamoto, J. Electrochem.

Soc. 142 (1995) 1431.

[123] L.S. Selwyn, W.R. McKinnon, U. von Sacken, C.A.

Jones, Solid State Ionics 22 (1987) 337.

[124] L.W. Shacklette, J.E. Toth, N.S. Murphy, R.H.

Baughman, J. Electrochem. Soc. 132 (1985) 1530.

[125] Y. Idota et al., US Patent 5,478,671.

[126] Y. Idota, T. Kubota, A. Matsufuji, Y. Maekawa, T.

Miyasaka, Science 276 (1997) 1395.

[127] I.A. Courtney, J.R. Dahn, J. Electrochem. Soc. 144

(1997) 2045.

[128] I.A. Courtney, J.R. Dahn, J. Electrochem. Soc. 144

(1997) 2943.

[129] J. Yang, M. Winter, J.O. Besenhard, Solid State Ionics

90 (1996) 281.

[130] S. Denis, E. Baudrin, M. Touboul, J.M. Tarascon, J.


[131] M. Nishijima, N. Tadakoro, Y. Takeda, N. Imanishi,

O. Yamamoto, J. Electrochem. Soc. 141 (1994) 2966.

[132] T. Shodai, S. Okada, S. Tobishima, J. Yamaki, Solid

State Ionics 8688 (1996) 785.


Documents

Broussely, 1999 - Revew Batteries