Novel solid polymer electrolytes

An amorphous ionically conductive macromolecular solid is set forth having improved ambient temperature ionic conductivity. The solid comprises a solid solution of at least one positively charged ionic species dissolved in a macromolecular material, the macromolecular material comprising a polymer or copolymer having a polyether structure and having at least a portion of the ether oxygens thereof replaced with S or NR wherein R includes at least one basic site capable of associating with the positively charged ionic species and has 2 to 10 carbon atoms. Relatively high conductivity is a feature of the macromolecular solid of the invention.

FIELD OF INVENTION 
The invention relates to solid polymer electrolytes useful in rechargeable 
batteries, power supplies, capacitors and microelectrochemical sensors. 
BACKGROUND ART 
Use of solid electrolytes goes back to Michael Faraday's report in 1834 
that solid lead fluoride at red heat would conduct electricity as would 
the metallic vessel in which he was heating it. More recently, the use of 
polymers of ethylene oxide and/or propylene oxide, sometimes along with 
other copolymeric materials, has provided a solid polymer material useful 
as an electrolyte and as a positive electrode material in high rate thin 
film batteries or capacitors capable of pulse discharge. Such materials 
are described, for example, in U.S. Pat. No. 4,578,326, issued Mar. 25, 
1986 to Michel Armand, et al and in U.S. Pat. No. 4,683,181, issued July 
28, 1987, to Michel Armand, et al. A more general description of such 
electrolytes can be found in the May 20, 1985 volume of Chemical and 
Engineering News, pages 43, 44 and 50-57. This article, particularly on 
pages 54-55 discusses polymeric solid electrolytes including poly 
(ethylene oxide) polymers (PEO) and polymers using a highly flexible 
polyphosphazene backbone to which short-chain polyether groups are 
attached. 
High energy density, rechargeable solid polymer electrolyte (SPE) using 
solid state batteries, for example, the Li/SPE/TiS.sub.2 or Li/SPE/V.sub.6 
O.sub.13 systems, promise virtually maintenance-free reliable operation 
over many thousands or ten of thousands of cycles if certain 
physico-chemical problems can be overcome. The most important problems are 
as follows: 
(1) The low mobility of Li.sup.+ in the SPE. 
(2) The difficulty of maintaining intimate contact between the SPE and the 
lithium negative and TiS.sub.2 interaction positive electrodes. 
(3) The occasional growth of a lithium dendrite that penetrates the SPE on 
recharging. 
(4) Low positive electrode utilization on rapid charging. This problem is 
not due to the SPE itself, but reflects a limitation of existing 
intercalation positive electrodes (e.g., TiS.sub.2). 
(5) Long-term thermal stability at the temperatures at which SPE batteries 
are likely to operate (e.g., 80.degree.-100.degree. C.). 
Research has expanded considerably in the development of solid polymer 
electrolytes for applications in high energy density batteries, specific 
ion sensors, and electronic displays. Wright and coworkers (British 
Polymer Journal 7, 319(1975) and Polymer 14, 589 (1973)) originally 
observed the ionic conductivity of complexes of alkali metal salts with 
poly(ethyleneoxide). M. B. Armand, and coworkers (Fast Ion Transport in 
Solids, Ed. P. Vashishita, North Holland, N.Y. (1979) p. 131; Second 
International Meeting on Solid Electrolytes, Saint Andrews University, 
Scotland (1978); Journal of the Electrochemical Society 132, 1333(1985)) 
developed a detailed understanding of the ionic conductivity of 
poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) salt complexes 
and proposed their use as solid polymer electrolytes in high energy 
density batteries. For the PEO-salt complexes, it has been suggested that 
the alkali metal cations reside in the helical tunnel of PEO, which is in 
a (T.sub.2 GT.sub.2 G) conformation. This structure is similar to the 
complexes between Li.sup.+, Na.sup.+, K.sup.+ and crown ethers. However, 
PEO and PPO complexes show ionic conductivity only above 100.degree. C. 
Recently, Blonsky, et al. (J. Amer. Chem. Soc. 106, 6854 (1984)) 
synthesized poly(phosphazene)-based ionic conductors that show good ionic 
conductivity at room temperature. However, the ionic conductivities are 
still too low to meet the power density requirements (&gt;100 W kg.sup.-1 
sustained power) for high density, rechargeable battery applications. 
Because SPEs, such as those based on poly(ethylene oxide) and 
polyphosphazene, are flexible, maintenance of intimate contact with the 
solid anode and cathode is less of a problem than with rigid solid 
electrolytes (e.g., Li-conducting glasses). However, the extent to which 
contact can be maintained depends on the negative (Li) and positive (e.g., 
TiS.sub.2, V.sub.6 O.sub.13) electrodes on charging and discharging. 
These problems would be greatly alleviated if it were possible to use 
relatively thick (&gt;500.mu.) SPE films, rather than films of &lt;100.mu. as 
currently used. The thin films that are now used are dictated by the low 
lithium ion conductivities of existing SPEs (See, for example, D. F. 
Shriver et al., Solid State Ionics 5, 83 (1981) and Chem. Eng. News (May 
20, 1985) p. 42). Therefore, a principal goal in developing SPE batteries 
is to increase the cation conductivity. This can be done only by providing 
new polymer systems that have the necessary structural properties to 
ensure high and stable cation conductivities under the conditions of 
interest. 
Two factors are critical to the transport of ions in polymer electrolytes: 
(1) liquid-like (amorphous) character of the polymer and (2) sites in the 
polymer that loosely bind with the ion to permit diffusion. Thus, having 
"floppy" polyether pendant groups on the polyphosphazene elastomer greatly 
reduces the glass transition temperature (T.sub.g) of the polymer. 
Consequently, when complexed with salts, this polymer shows substantially 
higher room temperature conductivity than the corresponding PEO complexes. 
However, the ionic conductance exhibited by the polyphosphazene 
electrolyte at room temperature is still too low for application in 
batteries. In addition, these polyphosphazene based electrolytes do not 
form good uniform flexible films. 
The present invention is directed to overcoming one or more of the problems 
as set forth above. 
DISCLOSURE OF INVENTION 
In accordance with an embodiment of the present invention an amorphous 
ionically conductive macromolecular solid is disclosed having improved 
ambient temperature ionic conductivity. The solid comprises a solid 
solution of at least one ionic species, said species including a cation, 
dissolved in a macromolecular material, the macromolecular material 
comprising a polymer or copolymer having a polyether structure and having 
at least a portion of the ether oxygens thereof replaced with S or NR 
wherein R includes at least one electronegative site capable of 
associating with the cation and has 2 to 10 carbon atoms. 
The amorphous (non-crystalline) character of the ionically conductive 
macromolecular solid allows for motion of the polymer to assist in the 
migration of ions such as Li.sup.+ through the solid from one electrode 
to another. The existence of the S and/or NR groups provides basic sites 
at which the positive ion, for example, Li.sup.+, is retained with lesser 
strength than it is retained in ethylene oxide or propylene oxide 
materials by the oxygens of the ether linkage. Thus, the positive ion is 
more mobile in such a polymer electrolyte.

BEST MODE FOR CARRYING OUT INVENTION 
The interaction between the alkali ion and the ether oxygen in the polymer 
complexes is a strong hard-acid/hard-base interaction as defined by the 
hard soft acid base (HSAB) principle. It has been found that the 
activation energy necessary for "hopping" of the alkali metal ion between 
sites can soft base like sulfur (or NR). Additionally, the conductance of 
the polymer complexes can be enhanced by organizing the pendant basic 
sites so that the "hopping" is stereochemically unhindered. 
In accordance with the present invention an amorphous ionically conductive 
macromolecular solid is set forth which has improved ambient temperature 
ionic conductivity. The solid includes a solid solution of at least one 
ionic species, including a cation, generally an alkali metal ion or 
ammonium ion, dissolved in a particular macromolecular material. The 
macromolecular material comprises a polymer or a copolymer having a 
polyether structure and having at least a portion of the ether oxygens 
replaced with either S or NR wherein R includes at least one basic site 
capable of associating with the cation and has 2 to 10 carbon atoms. 
Typical macromolecular materials useful in the practice of the invention 
may have, for example, any of the structures set forth in following Table 
I. 
TABLE I 
__________________________________________________________________________ 
STRUCTURES OF SOLID POLYMER ELECTROLYTES 
Polymer Unit S/O % 
__________________________________________________________________________ 
(1) (SCH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.2 OCH.sub.2 
CH.sub.2).sub.n 75 
(2) (SCH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.2 OCH.sub.2 
CH.sub.2 OCH.sub.2 CH.sub.2).sub.n 
60 
(3) (SCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2).sub.n 
50 
(4) (SCH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 
CH.sub.2).sub.n 50 
(5) (SCH.sub.2 CH.sub.2 SCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 
CH.sub.2 OCH.sub.2 CH.sub.2).sub. n 
40 
(6) (SCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2).sub.n 
33.33 
(7) (SCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 CH.sub.2 OCH.sub.2 
CH.sub.2 OCH.sub.2 CH.sub.2).sub.n 
20 
(8) (S(CH.sub.2 CH.sub.2 O).sub.6CH.sub.2 CH.sub.2).sub.n 
14 
(9) (S(CH.sub.2 CH.sub.2 O).sub.9CH.sub.2 CH.sub.2).sub.n 
10 
(10) 
##STR1## 
(11) 
##STR2## 
(12) 
##STR3## 
(13) 
##STR4## 
__________________________________________________________________________ 
The listed sulfur containing macromolecular materials have the mole 
percents sulfur shown in the righthand column with such percents sulfur 
representing the percent of the oxygen which has been replaced by sulfur. 
Structures 11-13 show compounds wherein all of the oxygens have been 
replaced with a group NR and wherein the R group is significantly 
different in each instance. In the instance of structures 11 and 12 an 
ether linkage exists in the R group whereby association to a cation is 
possible. In the structure labelled 13 a thioether linkage is present in 
addition to two ether linkages. It should be noted that the above 
structures are not meant to be exhaustive of the possibilities in this 
respect but are, instead, only meant to be illustrative of a few of such 
macromolecular materials. More generally, the group "R" can have from 2 to 
10 carbon atoms and may contain substantially any electronegative site 
which is capable of associating with the cation. And, macromolecular 
materials are useful wherein some of the oxygens are replaced by sulfurs 
and others by NR groups. Still further, it should be recognized that 
copolymers may be made with ethylene oxide, propylene oxide, and the like, 
if desired, and that such will still fall within the scope of the 
invention so long as they have the replacement S and/or NR substituents. 
The molecular weight of the macromolecular material of the present 
invention will generally fall within a range from about 10,000 to about 
3,000,000, and will preferably fall within a range from about 100,000 to 
about 1,000,000. 
With respect to the ionic compound such may comprise, for example, any of 
the following: LiCl, NaCl, KCl, LiCF.sub.3 SO.sub.3, LiClO.sub.4, 
LiAsF.sub.6, LiPF.sub.6, LiBF.sub.4, LiBr, LiI, LiSCN, LiOOCR', where R' 
may be alkyl, alkenyl, alkynyl or aromatic and includes 1 to 10 carbon 
atoms. Preferably, the cation is sodium or lithium. 
The term ambient temperature as used herein relates to temperatures in the 
range from about 15.degree. C. to about 45.degree. C. and more usually to 
temperatures in the range from about 18.degree. C. to about 40.degree. C. 
The macromolecular material in accordance with the invention generally has 
the formula: 
EQU --(X--C(R.sub.1).sub.2 C(R.sub.1).sub.2 --Y--C(R.sub.1).sub.2 
C(R.sub.1).sub.2).sub.n -- 
wherein X and Y are the same or different and are each independently O, S 
or NR wherein R includes at least one ether or thioether linkage or group 
--PO, --PO.sub.2, --PO.sub.3, --SbO, --SO, --SO.sub.2, --NR".sub.2 or 
--AsO, which serves as a basic site capable of associating with the 
cation. Generally, each R will include 2 to 10 carbon atoms. It may also 
include other atoms such as oxygen, sulfur, phosphorous, arsenic, 
antimony, nitrogen and hydrogen. Generally, at least about 25% of all X 
and Y are O. Generally no more than about 98% of all X and Y are O. Each 
R" may independently be hydrogen or alkyl, alkenyl or aryl with 1 to 10 
carbon atoms. 
Each R.sub.1 is the same or different and is independently hydrogen or a 
C.sub.1-4 saturated or unsaturated hydrocarbon radical optionally 
substituted with triallylsilyl, oxygen, sulfur or phosphate. 
The amorphous ionically conductive macromolecular solid of the present 
invention can be formulated as using conventional polymerization 
techniques. The (thio-oxyethylenes) were synthesized by two methods. In 
one method, thio-oxyethylene dithiols were reacted with equimolar amounts 
of thio-oxyethylene dichloride. This method provided polymers with 
molecular weights not exceeding 10,000 daltons. The second method, the 
reaction of thio-oxyethylene dithiols with 
N,N'-diisopropyl-O-ethyleneglycol bisisoureas, gave polymers with higher 
weight average molecular weights. Examples I-IX illustrate the formation 
of several such polymers. Example X illustrates the synthesis of a polymer 
with a side chain. 
EXAMPLE I 
Synthesis of Poly(thioether) 14% S 
Hexaethyleneglycol (5 g, 15.3 mmol) was placed in a 100 mL round-bottomed 
flask and dissolved in anhydrous dimethylformamide (20 mL) under nitrogen. 
Triphenylphosphine (9.03 g, 30.6 mmol) was added to the solution. Bromine 
(5 g) was added dropwise to the reaction mixture until persistence of an 
orange color. The addition was exothermic and the reaction temperature was 
controlled below 30.degree. C. by external cooling. The reaction mixture 
was stirred overnight under nitrogen. A precipitate which had formed was 
isolated and discarded. The dimethylformamide in the filtrate was 
distilled off under vacuum. The residue was taken up in water and 
extracted three times from methylene chloride (60 mL each). The organic 
layer was washed a few times with 10% NaOH and water and then dried over 
magnesium sulfate. After distillation of the solvent by rotary 
evaporation, the residue was flash chromatographed through silica gel 
using methylene chloride/acetone, 10:1 as eluent. Pure 
3.6.9.12.15.18-Hexaoxo-1,20-dibromoeicosane product (2 g) was isolated 
along with mixed fractions. 
The 3.6.9.12.15.18-Hexaoxo-1,20-dibromoeicosane (2 g, 4.42 mmol) and 
thiourea (0.73 g, 9.60 mmol) were dissolved in 95% ethanol (10 mL) at 
reflux. The reaction mixture was refluxed overnight. The solvent was 
distilled off and the residue was dissolved in water and methanol (30 mL 
and 10 mL, respectively). KOH (5 g) was added to the solution and the 
solution was refluxed overnight. After evaporation of the solvents the 
residue was flash chromatographed on silica gel using methylene 
chloride/acetone, 85:15, as eluent. The 
3,6,9,12,15,18-Hexaoxa-1,20-eicosanedithiol product (0.5 g) was isolated 
in 33% yield. 
Heptamethyleneglycol (5 g, 15.3 mmol) was weighed into a 25-mL round 
bottomed flask under nitrogen. A catalytic amount of anhydrous copper 
chloride (62 mg) was added to the flask. 3,3'-Diisopropylcarbodiimide 
(4.06 g, 32.2 mmol) was added. The reaction mixture was stirred at room 
temperature for 24 hours. Anhydrous hexane (100 mL) was added to the 
reaction mixture and the resulting solution was filtered through Celite. 
After evaporation of the solvent the desired heptaethylglycol 
diisopropylbisisourea product was recovered in quantitative yield. 
3,6,9,12,15,18-Hexaoxa-1,20-eicosanedithiol (0.48 g., 1.34 mmol), 
heptaethylglycol diisopropylbisisourea (0.775 g., 1.34 mmol), and 
anhydrous potassium fluoride (0.124 g., 2.14 mmol) were transferred into a 
glass ampoule, that was then degassed and sealed under vacuum. The 
reaction mixture was heated at 140.degree. C. for three days. After 
cooling down, a few mLs of chloroform were added to the reaction mixture, 
and the insoluble potassium fluoride and diisopropylurea were filtered 
out. The polymer was dialyzed (molecular weight cut-off 3,500) in 
water/methanol 1:1 for three days. The polymer was recovered as a viscous 
oil (0.55 g) and was characterized by .sup.1 H NMR and gel permeation 
chromatography (6000 daltons average weight molecular weight. 
EXAMPLE II 
Synthesis of Poly(thioether) 20% S 
3,6,9,12-Tetraoxa-1,14-tetradecanedithiol (1.6 g., 5.92 mmol), 
pentaethylene glycol diisopropylbis-isourea (2.16 g., 5.92 mmol) and 
anhydrous potassium fluoride (0.55 g., 9.45 mmol) were transferred into a 
glass ampoule. The glass ampoule was degassed, sealed under vacuum and 
heated at 140.degree. C., in an oil bath, for three days. After this time, 
the reaction mixture was transferred into a beaker and stirred in 
chloroform, and were removed by filtration. The filtrate was concentrated, 
methanol was added and the mixture was transferred into a dialysis bag 
(molecular weight cut-off 3500) and dialyzed against water/methanol 1:1. 
The polymer was isolated as a viscous oil in 60% yield, and characterized 
by .sup.1 H NMR and gel permeation chromatography (105,000 daltons average 
weight molecular weight against monodispersed polystyrenes). 
EXAMPLE III 
Synthesis of Poly(thioether) 50% S (SOSO) 
2-Mercaptoethylether (8 g., 57.87 mmol), disopropyldiethylene glycol 
bisisourea (20.75 g., 57.87 mmol) and anhydrous potassium fluoride (5.38 
g., 92.59 mmol) were weighed into a glass ampoule, degassed and sealed 
under vacuum. The reaction vessel was heated in an oil bath at 140.degree. 
C. for six days. Chloroform was added to the reaction mixture, and the 
insoluble diisopropylurea and potassium fluoride were filtered out. The 
filtrate was concentrated and added to methanol, where the polymer 
precipitated out as a slightly yellow solid. The product, after drying at 
25.degree. C. at 0.1 torr for sixteen hours, was isolated in 65% yield 
(7.83 g). 
EXAMPLE IV 
Synthesis of Poly(thioether) 10% S 
3,6,9,12,15,18,21,24,27-Nonaoxa-1,30-dibromotriacontane was contacted in 
one to one mole ratio with Na.sub.2 S and with tricaprylmethylammonium 
chloride (one-tenth the molar amount of Na.sub.2 S), the latter two 
reactants being dissolved in water, for approximately 96 hours at 
100.degree. C. to produce the desired product. 
EXAMPLE V 
Synthesis of Poly(thioether) 75% S 
The desired compound was synthesized by each of two methods (A and B) as 
follows: 
Method A 
2-Mercaptoethylsulfide (1.2 g, 7 mmol) was transferred into a 100 mL 
round-bottomed flask under nitrogen. Absolute ethanol (10 mL) was poured 
into the flask, and tetramethylammonium hydroxide pentahydrate (2.62 g, 14 
mmol) was added. The reaction solution was heated at reflux. 
2-Chloroethylether (1 g, 7 mmol) was dissolved in anhydrous benzene (30 
mL) and quickly added to the reaction solution. The reaction was refluxed 
overnight. The formed precipitate was filtered out, stirred twice in 
ethanol (50 mL), and filtered again. After drying at 40.degree. C. under 
vacuum, 1 g (64% yield) was collected. The polymer was insoluble in most 
of the common organic solvents; however, it was soluble in hot 
dimethylformamide and hot dimethylsulfoxide. The polymer was characterized 
by .sup.1 H NMR in d.sub.6 -dimethylsulfoxide: no molecular weight 
determination was made. 
Method B 
2-Mercaptoethylsulfide (4 g, 25.92 mmol), 
N,N'-diisopropyl-O-diethyleneglycol bisisourea (9.29 g, 25.92 mmol) were 
weighed into a glass ampoule, degassed, and sealed under vacuum. The tube 
was heated in an oil bath at 140.degree. C. for 113 hours. The product was 
removed from the ampoule, stirred in chloroform, and filtered. The 
filtrate was concentrated and added to methanol. Just a small amount of 
solid precipitated out (about 300 mg). Most of the reaction product was 
therefore isolated in the chloroform-insoluble portion. The gray solid was 
very hard and could not be dissolved in common organic solvents. 
EXAMPLE VI 
Synthesis of Poly(thioether) 60% S 
The desired compound was synthesized by each of two methods (A and B) as 
follows: 
Method A 
2-Mercaptoethylsulfide (4.58 g, 26.7 mmol) and tetramethylammonium 
hydroxide pentahydrate (9.68 g, 53.4 mmol) were weighed into a 250-mL 
round-bottomed flask and dissolved in ethanol (20 mL). The solution was 
heated to 80.degree. C., and 1,2-bis(2-chloroethoxy)ethane (5 g, 26.7 
mmol) dissolved in benzene (150 mL) was added at once. The solution was 
stirred and heated for 20 hours. On cooling of the reaction, a white solid 
precipitated out. It was filtered and washed with methanol. The solid was 
stirred in water (100 mL) and filtered again. After drying at 40.degree. 
C. under vacuum, a white solid (4.21 g, 58.7%) was collected. No molecular 
weight analysis was run since the product was insoluble in 
tetrahydrofuran. 
Method B 
2-Mercaptoethylsulfide (12.96 g, 12.96 mmol), 
N,N'-diisopropyl-O-triethyleneglycol bisisourea (5.22 g, 12.96 mmol), and 
anhydrous potassium fluoride (1.20 g, 20.74 mmol) were weighed into a 
glass ampoule, degassed, and sealed under vacuum. The ampoule was heated 
at 140.degree. C. for 94.5 hours. The product was removed from the ampoule 
and stirred in chloroform. The insoluble portion was collected by 
filtration and washed a few times with methanol and water. After drying 
under vacuum at room temperature for 16 hours, a gray powder (2.12 g) was 
obtained that was insoluble in methanol, water, dimethylsulfoxide, 
tetrahydrofuran, and chloroform. No. molecular weight analysis was run. 
EXAMPLE VII 
Synthesis of Poly(thioether) 40% S 
The desired compound was synthesized by each of two methods (A and B) as 
follows: 
Method A 
2-Mercaptoethylether (5.5 g, 36.2 mmol) and tetramethylammonium hydroxide 
pentahydrate (13.2 g, 72.4 mmol) were weighed in a 250-mL round-bottomed 
flask and dissolved in ethanol (10 mL). 1,2-Bis(2-chloroethoxy)ethane 
(6.67 g, 36.2 mmol) was dissolved in benzene (100 mL) and added to the 
reaction. The reaction was stirred under reflux overnight. After cooling, 
the ethanolic phase was separated from the benzene phase. The benzene was 
distilled off and the residue was dried under vacuum at 100.degree. C. for 
two hours. A white solid (9 g) was obtained. The polymer was dissolved in 
tetrahydrofuran, and an average weight molecular weight of 4,100 daltons 
was found by GPC analysis. 
Method B 
1,2-Mercaptoethylether (8 g, 57.87 mmol), 
N,N'-diisopropyl-O-triethyleneglycol bisisourea (23.30 g, 57.87 mmol), and 
potassium fluoride (5.38 g, 92.59 mmol) were transferred into a glass 
ampoule, degassed, and sealed under vacuum. The tube was heated at 
140.degree. C. for six days. The product was then stirred in chloroform, 
and the insoluble portion was filtered out. The concentrated chloroform 
solution was added dropwise into methanol, and the precipitate was 
collected by filtration. After drying at room temperature under vacuum 
overnight, a slightly yellow solid product (2.64 g) was collected. The 
polymer was almost totally insoluble in tetrahydrofuran, so GPC analysis 
could not be run. 
EXAMPLE VIII 
Synthesis of Poly(thioether) 33% S 
The desired compound was synthesized by each of two methods (A and B) as 
follows: 
Method A 
3,6-dioxo-1,8-dimercaptooctane (7 g, 38.4 mmol) and tetramethylammonium 
hydroxide pentahydrate (14 g, 76.8 mmol) were dissolved in ethanol (10 
mL). 1,2-Bis(2-chloroethoxy)ethane (7.18 g, 38.4 mmol) was dissolved in 
benzene (100 mL) and added to the ethanol solution. The reaction was 
refluxed overnight. The benzene phase was separated from the ethanol 
phase. The benzene was distilled off, and a pale yellow solid (10.02 g) 
was obtained. A weight average molecular weight of about 2,000 daltons was 
determined by GPC analysis. 
Method B 
3,6-1,8-dimercaptooctane (10 g, 54.87 mmol), 
N,N'-diisopropyl-O-triethyleneglycol bisisourea (22.09 g, 54.87 mmol), and 
anhydrous potassium fluoride (5.10 g, 87.79 mmol) were sealed under vacuum 
in a glass ampoule and heated at 140.degree. C. for six days. The solid 
residue was stirred in chloroform, and the insoluble portion removed by 
filtration. The chloroform solution was added dropwise into methanol, and 
the product was isolated as a white solid by filtration. The polymer was 
dissolved in tetrahydrofuran, and a weight average molecular weight of 
7,400 daltons was calculated versus standard polystyrenes. 
EXAMPLE IX 
Synthesis of Poly(thioether) 50% S (SSOO) 
1,2-Dimercaptoethane (8 g, 0.849 mol), N,N'-diisopropyl-O-triethyleneglycol 
bisisourea (34.19 g, 0.849 mmol), and anhydrous potassium fluoride (7.89 
g, 1.36 mol) were transferred into a glass ampoule, degassed, sealed under 
vacuum, and heated at 140.degree. C. for six days. The residue was removed 
from the reaction vessel and stirred in chloroform. The insoluble material 
was separated by filtration. The solution in chloroform was concentrated 
and dropped into methanol to precipitate out the product. The milky white 
fluffy material was filtered, then dried at room temperature under vacuum 
for 16 hours (yield: 7.5 g). The polymer was dissolved in tetrahydrofuran, 
and a weight average molecular weight of about 7,000 daltons was 
determined versus standard polystyrenes. 
EXAMPLE X 
Synthesis of Polyethyleneimine Derivative (NSOO) 
To a stirred solution of methoxyethoxymethyl-thioglycolic acid (1 g) in 
dichloromethane maintained at 0.degree. C. under nitrogen was added a 
solution of dicylohexylcarbodiimide (1.14 g) in dichloromethane. After 30 
minutes stirring at 0.degree. C., a solution of polyethyleneimine (0.239 
g) in dichloromethane was added. The stirred reaction mixture was allowed 
to warm to room temperature and kept at room temperature for 24 hours. The 
product was filtered and the filtrate washed successively with 0.1N HCl 
and brine. The organic extract was dried over anhydrous magnesium sulfate 
and the solvent evaporated under vacuum. The solid residue was dissolved 
in dry, distilled tetrahydrofuran under dry nitrogen at 0.degree. C. and 
borane/tetrahydrofuran solution (1 Molar, 72 mL) was added. The reaction 
was allowed to warm to room temperature and stirred overnight under 
nitrogen. The reaction mixture was then heated under reflux for 1 hour. 
The solvent was removed under vacuum and the residue heated under reflux 
with methanolic sodium hydroxide (40 mL methanol+20 mL 10% NaOH). Methanol 
was distilled off and the residue was dissolved in 1N hydrochloric acid 
and filtered. The filtrate was washed with dichloromethane and the aqueous 
solution basified with 25% sodium hydroxide. The basic solution was 
extracted repeatedly with dichloromethane and the organic extract washed 
with saturated brine. The organic extract was dried over anhydrous 
magnesium sulfate and filtered. The solvent was distilled off and the 
polymer residue dried under vacuum to yield the NSOO polymer in 60% yield. 
Batteries for testing were prepared as follows: 
Materials 
All procedures for handling the cell materials were conducted in a nitrogen 
dry box. Batteries containing Li metal were assembled in an argon dry box 
to prevent any reaction of lithium with nitrogen to form lithium nitride. 
Tetrahydofuran (THF) was distilled from Na/benzophenone under nitrogen 
before use. Chloroform was distilled from calcium hydride under nitrogen. 
Acetonitrile was distilled from P.sub.2 O.sub.5. Lithium 
trifluoromethanesulfonate (LiCF.sub.3 SO.sub.3) obtained from Aldrich 
Chemical Co., was used as received. Lithium ribbon (0.38 mm thick.times.50 
mm wide) was obtained from AESAR and stored under argon. Ammonium vanadate 
(Aldrich Chemical Co., 99.99%) was used without further purification. 
Shawinigan black (50% compressed) was obtained from Chevron Chemical Co., 
MoS.sub.2 cathodes produced by chemical vapor deposition (CVD) on an 
aluminum substrate were obtained from Polytechnic University, Brooklyn, 
N.Y. Polyethylene oxide (PEO, M. Wt. 100,000) was obtained from Aldrich 
Chemical Co., and dried at 140.degree. C. before use. 
Equipment And Measurement Technique 
Conductivities of the polymers were evaluated by AC impedance spectroscopy. 
Preparation of the electrolyte films and the V.sub.6 O.sub.13 cathodes and 
assembly of the batteries are discussed in later sections. A film 6 of the 
dried polymer electrolyte was sandwiched between two stainless steel 
blocking electrodes 7,8 that each had an area of 0.7854 cm.sup.2 The 
thickness of the polymer film 6 which typically varied between 0.51 mm and 
1.02 mm was measured with a micrometer. The assembly 9 composed of the 
blocking electrode-polymer sandwich cell 10 inside a Delrin cup 12 (FIG. 
1) was transferred to a vacuum chamber 14 that had provision for heating 
(FIG. 2) and for applying a constant pressure of 65-97 lb/in.sup.2 across 
the polymer film 6. The electrodes 7,8 were connected to a potentiostat 
( 173) operating in the galvanostatic mode. 
The cell 10 was then perturbed with a small AC signal generated by a 
Solartron 1250 Frequency Response Analyzer, and the real and imaginary 
components of the cell impedance were measured as a function of frequency 
at each of the desired temperatures. The setup was allowed to stabilize 
overnight after the temperature was changed. The AC impedance data were 
plotted in both the Nyquist and Bode planes to identify the high frequency 
relaxation arising due to the polymer electrolyte. Typically, the 
frequency of the AC signal was scanned from 65 KHz down to 10 mHz. The 
intercept at the real axis of the high frequency relaxation was assumed to 
represent the resistive component of the polymer electrolyte impedance. 
This was then converted to the resistivity of the polymer (the thickness 
and the area of the polymer film 6 were known). The reciprocal of 
resistivity gave the conductivity, .sigma., having units of .OMEGA..sup.-1 
cm.sup.-1. In cases where high frequency relaxation occurred above 65 KHz, 
a Hewlett Packard 4192A Impedance Analyzer was used to measure the polymer 
electrolyte resistance. This instrument has a frequency range capability 
of 13 MHz to 5 Hz. The experimental setup 16 used for conductivity 
measurements is shown in FIG. 3. 
The battery performance tests utilized a 173 potentiostat/galvanostat 
to produce constant current charge/discharge cycles between predetermined 
voltage levels. 
Preparation Of Polymer/Lithium Complexes 
Solutions of polymer/Li triflate complexes were prepared by dissolving a 
known quantity of LiCF.sub.3 SO.sub.3 and polymer in dry solvent. The 
weights used were such that the molar ratio of oxygen atoms plus sulfur 
atoms to lithium atoms was 8. (The oxygen atoms in the backbone of the 
polymer are not used in the calculation). The mixture was then allowed to 
stand overnight. 
For conductivity measurements, the polymer/Li complex solution was added 
dropwise into the Delrin cup to cast a film. The film was then dried for 3 
days in a glass vacuum apparatus at 120.degree. C. at &lt;0.01 torr. Film 
thickness was measured using a micrometer. 
For battery tests, the solvent from the polymer/Li complex solution was 
allowed to evaporate in the dry box. The complex was then transferred to 
the Delrin cup and vacuum dried as described above. 
Preparation Of V.sub.6 O.sub.13 Cathodes 
Vanadium oxide was prepared by thermally decomposing ammonium vanadate in 
argon. NH.sub.4 VO.sub.3 was placed in a quartz boat and flushed with 
argon for 30 minutes. The temperature was then raised from room 
temperature to 500.degree. C. at a rate of 4.degree./min. After 1 hour at 
500.degree. C., the temperature was raised to 550.degree. C. at a rate of 
4.degree./min., held at 55.degree. C. for 1 hour and then slowly cooled to 
room temperature. The product obtained was dark blue in color. 
The composition of the cathode was 80% V.sub.6 O.sub.13, 5.5% Shawinigan 
black, and 14.5% polymer/LiTF complex by weight. The amounts of V.sub.6 
O.sub.13 and Shawinigan black required were weighed into a polycarbonate 
vial and ground for 5 minutes in a Wig-L-Bug grinder. The mixture was 
dried for 3 days at 140.degree. C. and &lt;0.1 torr in an Abderhalden drying 
apparatus. In a 3 mL vial, 100 mg of polymer/LiTF complex was mixed with 
589.7 mg of V.sub.6 O.sub.13 /Shawinigan black in THF. The mixture was 
intermittently shaken and allowed to stand overnight before the solvent 
was evaporated off in the dry box. The cathode mixture (100 mg) was 
pressed at 10,000 lb for 3 minutes in a stainless steel die with area of 
1.69 cm.sup.2. 
Battery Assembly 
MoS.sub.2 and V.sub.6 O.sub.13 cathodes were cut to size with a 
1-cm-diameter punch. The cathodes were attached to the stainless steel 
plate in the Delrin cup with conducting epoxy (Cho-Bond 584). The adhesive 
was cured at 120.degree. C. for 1 hour. Approximately 100 mg of the 
polymer/LiTF complex was weighed into the cup to form a film, as described 
above. Lithium anodes were freshly prepared by cutting lithium ribbon with 
the same punch and sanding the surfaces with emery paper. The cup was then 
loaded into the cell assembly as shown in FIG. 1. 
Table II lists the experimentally determined conductivities of various 
amorphous ionically conductive macromolecular solids in accordance with 
the present invention as compared with the ionic conductivity of 
polyethylene oxide. 
FIG. 4 shows the experimental results obtained using various polymer 
systems in accordance with the invention in comparison with PEO via a 
graph of log sigma (conductivity) vs 1000/T.degree.K of the cell where 
T.degree.K is the temperature in degrees Kelvin. The compositions tested 
are listed in Table I. Note that by proper selection of the polymer system 
conductivity increases of five orders of magnitude are attainable. 
TABLE II 
______________________________________ 
Conductivity Data Measured at 25.degree. C. 
Polymer Electrodes 
Conductivity 
______________________________________ 
PEO SS/SS .sup. 2.51 .times. 10.sup.-11 
10% S SS/SS 7.10 .times. 10.sup.-5 
14% S SS/SS 4.22 .times. 10.sup.-7 
20% S SS/SS 1.27 .times. 10.sup.-6 
20% S Li/V.sub.6 O.sub.13 
1.98 .times. 10.sup.-6 
33% S SS/SS 1.10 .times. 10.sup.-7 
40% S SS/SS .sup. 9.13 .times. 10.sup.-10 
50% S (SSOO) SS/SS .sup. 1.62 .times. 10.sup.-10 
50% S (SOSO) SS/SS .sup. 6.38 .times. 10.sup.-10 
60% S SS/SS 1.40 .times. 10.sup.-8 * 
75% S SS/SS .sup. 4.64 .times. 10.sup.-10 ** 
N--SOO*** SS/SS 9.18 .times. 10.sup.-9 
NCH.sub.2 OC.sub.2 H.sub.5 
SS/SS 7.69 .times. 10.sup.-7 
______________________________________ 
*indicates 35.degree. C. measurement. 
**indicates 65.degree. C. measurement. 
***indicates structure 13 of Table I 
SS indicates stainless steel. 
The lithium salt was the triflate and the molar ratio of oxygen plus sulfur 
(or nitrogen) to lithium was 8 in all instances. Conductivity is in 
ohms.sup.-1 cm.sup.-1. 
Industrial Applicability 
The present invention provides an amorphous ionically conductive 
macromolecular solid having use as a solid polymer electrolyte and/or as 
an electrode. Relatively high conductivity is provided and such is 
believed to be due to improved mobility of the positively charged ionic 
species throughout the macromolecular material which forms the major 
portion of the macromolecular solid. 
While the invention has been described in connection with specific 
embodiments thereof, it will be understood that it is capable of further 
modification, and this application is intended to cover any variations, 
uses, or adaptations of the invention following, in general, the 
principles of the invention and including such departures from the present 
disclosure as come within known or customary practice in the art to which 
the invention pertains and as may be applied to the essential features 
hereinbefore set forth, and as fall within the scope of the invention and 
the limits of the appended claims.