U.S. patent application number 14/396839 was filed with the patent office on 2015-08-20 for 1.5-3 v lithium batteries with overcharge protection.
The applicant listed for this patent is Rockwood Lithium GmbH. Invention is credited to Ute Emmel, Irina Tschernych, Ulrich Wietelmann.
Application Number | 20150236382 14/396839 |
Document ID | / |
Family ID | 48182911 |
Filed Date | 2015-08-20 |
United States Patent
Application |
20150236382 |
Kind Code |
A1 |
Wietelmann; Ulrich ; et
al. |
August 20, 2015 |
1.5-3 V LITHIUM BATTERIES WITH OVERCHARGE PROTECTION
Abstract
Rechargeable, non-aqueous lithium batteries which contain, as
active anode material, either lithium metal or a lithium alloy, an
active cathode material with a redox potential in the range of
between 1.5 and 3.4 V vs. Li/Li.sup.+ and lithium rhodanide (LiSCN)
as electrolyte component.
Inventors: |
Wietelmann; Ulrich;
(Friedrichsdorf, DE) ; Emmel; Ute; (Frankfurt am
Main, DE) ; Tschernych; Irina; (Malsch, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Rockwood Lithium GmbH |
Frankfurt a.M. |
|
DE |
|
|
Family ID: |
48182911 |
Appl. No.: |
14/396839 |
Filed: |
April 24, 2013 |
PCT Filed: |
April 24, 2013 |
PCT NO: |
PCT/EP2013/058473 |
371 Date: |
January 14, 2015 |
Current U.S.
Class: |
429/337 ;
429/188; 429/199; 429/200; 429/339; 429/341; 429/343 |
Current CPC
Class: |
H01M 2300/0034 20130101;
H01M 4/405 20130101; H01M 4/38 20130101; H01M 10/0567 20130101;
H01M 10/0525 20130101; H01M 4/382 20130101; H01M 4/58 20130101;
H01M 10/0565 20130101; Y02E 60/10 20130101; H01M 2300/0085
20130101; H01M 4/505 20130101; H01M 4/582 20130101; H01M 10/4235
20130101; H01M 10/0569 20130101; H01M 4/483 20130101; H01M
2300/0082 20130101; H01M 2300/0091 20130101; H01M 4/587 20130101;
H01M 10/052 20130101; H01M 2300/0028 20130101; H01M 10/0568
20130101; H01M 4/502 20130101 |
International
Class: |
H01M 10/42 20060101
H01M010/42; H01M 10/0569 20060101 H01M010/0569; H01M 10/0567
20060101 H01M010/0567; H01M 4/48 20060101 H01M004/48; H01M 4/38
20060101 H01M004/38; H01M 4/40 20060101 H01M004/40; H01M 4/58
20060101 H01M004/58; H01M 4/50 20060101 H01M004/50; H01M 10/0568
20060101 H01M010/0568; H01M 10/0525 20060101 H01M010/0525 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 26, 2012 |
DE |
10 2012 008 178.2 |
Claims
1.-15. (canceled)
16. A lithium battery comprising: lithium metal or a lithium alloy
as an active anode material; and a material having a redox
potential in the range between 1.5 and 3.4 V vs. Li/Li.sup.+ as an
active cathode material; and lithium rhodanide as an electrolyte;
wherein the lithium battery is rechargeable and nonaqueous.
17. The rechargeable nonaqueous lithium battery according to claim
16, wherein powdered lithium metal or a powdered lithium alloy
which may be present in a compacted form is included as the active
anode material.
18. The lithium battery according to claim 16, wherein the cathode
material is selected from the group consisting of CF.sub.x, a
transition metal oxide, a transition metal sulfide, a transition
metal fluoride, a transition metal oxyfluoride, an organic
redox-active compound, sulfur and selenium.
19. The lithium battery according to claim 18, wherein the cathode
material is selected from the group consisting of CF.sub.x,
MnO.sub.2, V.sub.2O.sub.5, V.sub.6O.sub.13, FeOF, FeF.sub.3,
FeF.sub.2 and S.
20. The lithium battery according to claim 16, wherein the
electrolyte is in a liquid, gelatinous or solid state at room
temperature.
21. The lithium battery according to claim 20, wherein the
electrolyte contains organic aprotic solvents selected from the
group consisting of a cyclic ether, an acyclic ether, a polyether,
a nitrile, a lactone, a carbonic acid ester and an ionic
liquid.
22. The lithium battery according to claim 21, wherein the
electrolyte contains at least one organic aprotic solvent selected
from the group consisting of tetrahydropyran, tetrahydrofuran,
1,2-dimethoxyethane, diethylene glycol dimethyl ether,
acetonitrile, adiponitrile, malodinitrile, glutaronitrile,
y-butyrolactone and an imidazolium salt.
23. The lithium battery according to claim 16, wherein the
electrolyte contains LiSCN and at least one additional conductive
salt.
24. The lithium battery according to claim 16, wherein the
additional conductive salt is selected from the group consisting of
LiPF.sub.6, a lithium fluoroalkyl phosphate, LiBF.sub.4, an imide
salt, LiOSO.sub.2CF.sub.3, a methide salt, LiClO.sub.4, a lithium
chelatoborate, a lithium fluorochelatoborate, a lithium
chelatophosphate, a lithium fluorochelatophosphate and a lithium
halide.
25. The lithium battery according to claim 16, wherein the
electrolyte comprises at least one organic polymer selected from
the group consisting of polyethylene oxide, polyacrylonitrile and
polyvinylidene fluoride.
26. The lithium battery according to claim 16, wherein the LiSCN is
present in the electrolyte in a concentration of 0.01 to 15 wt
%.
27. The lithium battery according to claim 16, wherein the LiSCN is
present in the electrolyte in a concentration of 1 to 10 wt %.
28. An electrolyte for use in the lithium battery according to
claim 16, wherein lithium rhodanide is present as the electrolyte
component.
29. The electrolyte according to claim 28, wherein the LiSCN is
present in the electrolyte in a concentration of 0.01 to 15 wt
%.
30. A battery electrolyte comprising LiSCN as a redox shuttle
compound.
Description
[0001] Lithium ion batteries (LiBs) are battery systems having the
highest specific energy density at the present time. They consist
of a combination of two lithium insertion materials which are
capable of reversibly inserting and deinserting lithium ions at
different potential levels. In general, the cathode (the positive
terminal) consists of a lithium metal oxide, while the anode (the
negative active terminal) contains a graphitic material. The anode
reaction is then as follows:
Li.sup.++e.sup.-+6CLiC.sub.6
[0002] The theoretical capacitance of graphitic materials is given
by the limiting stoichiometry of LiC.sub.6, and is 372 mAh/g.
[0003] Anode materials having a higher capacitance are also known,
first and foremost being lithium metal itself, which has a
theoretical specific capacitance of 3,860 MAh/g.
[0004] However, it is impossible to use lithium metal anodes in
combinations with "traditional" lithium ion cathode materials
(i.e., lithium metal oxides) because in this case both of the
electrodes are already in the lithiated state. Therefore, if
lithiated anode materials are to be used, in particular lithium
metal itself, then non-lithiated (or partially lithiated) cathode
materials must be used. Such materials include, for example, the
following:
TABLE-US-00001 Oxidation potential Non-lithiated Cathode Materials
vs. Li/Li.sup.+ (V) CF.sub.x 3.2 Transition metal oxides, e.g.:
1.5-3.4 MnO.sub.2 3 V.sub.2O.sub.5 1.9-3.4 V.sub.6O.sub.13 2-2.8
CuO 1.5 Transition metal sulfides, e.g.: 1-2.1 FeS.sub.2 1.5
MoS.sub.2 1-2 TiS.sub.2 2.1 F-containing conversion cathode
materials, e.g.: 2-3.5 BiF.sub.3, Bi.sub.2O.sub.3-xF.sub.2x, FeOF,
FeF.sub.3, FeF.sub.2, CoF.sub.3, CoF.sub.2, TiF.sub.3, VF.sub.3,
MnF.sub.3, NiF.sub.2, CrF.sub.3, CuF.sub.2 Organic cathode
materials, 2-2.5 e.g., tetraketopiperazines, polyanthraquinone
sulfides, pyromellitic acid anhydride S 2.0-2.4 Se 2.1
[0005] When such materials are overcharged, irreversible structural
changes may occur which may impair or completely destroy the
functionality of the cathode material. In general, the Li insertion
potential should not be exceeded by more than approximately 0.5-1.5
V. In addition, it is important to prevent the charging potential
from being exceeded, because otherwise, electrolyte components,
e.g., organic solvents, may be oxidized with release of energy. The
carbonates that are typically used in lithium ion batteries are
stable to approximately 4.4 V vs. Li/Li.sup.+, but they are not
very suitable for galvanic cells with lithium metal anodes or
lithium alloy anodes. To be able to use metal anodes,
reduction-stable solvents, usually ethers, are required. However,
such solvents (dimethoxyethane, diethyl ether) are stable only to
approximately 3.6 V (K. Xu, "Electrolytes: Overview" in
Encyclopedia of Electrochemical Power Sources, J. Garche (ed.),
Vol. 5, p. 51, Elsevier, Amsterdam 2009).
[0006] Such a restriction on the charging potential may be
implemented electronically by a battery management system, which is
relatively complex and may result in dangerous disturbances in the
event of a malfunction. It is therefore desirable to have an
inherent (chemical) protective system that prevents the desired
final charging potential from being exceeded. Such a system is
supplied by so-called redox shuttle compounds. Such compounds are
oxidized when a certain charging potential is exceeded. The
oxidized form is stable and can travel by migration or diffusion to
the anode, where it can be discharged (reduced) to the initial
form. The reduced species may then be oxidized again on the anode,
etc.
[0007] No reversible redox shuttle compounds have yet been
described for the aforementioned cathode materials.
[0008] The object of the present invention is to provide a
rechargeable nonaqueous lithium battery which contains a reversible
redox shuttle compound and oxidizes reversibly at approximately
0.5-1.5 V above the charging potential of lithium-free cathode
materials and below the start of decomposition of ethereal solvents
(approximately 3.6 V).
[0009] This object is achieved according to the invention by a
rechargeable nonaqueous lithium battery, which contains either
lithium metal or a lithium alloy as active anode material in the
charged state , and an active cathode material having a redox
potential in the range between 1.5 and 3.4 V vs. Li/Li' and lithium
rhodanide (LiSCN) as an electrolyte component.
[0010] Powdered lithium metal or a powdered lithium alloy is
preferably present as the active anode material. These anodes
produced from powdered particles may be present in a mechanically
compacted form by pressing, rolling or the like, or may be
compressed by sintering, to obtain a structure that is
macroscopically similar to sheet metal. However, the compacted
powder anode is characterized by a composite structure; i.e., the
phase boundaries of the powdered primary particles are discernible
by high resolution imaging methods (scanning electron microscopy,
for example). The use of powdered anode layers or anode layers
derived from powders has the advantage that the specific current
load (i.e., relative to a unit surface area) is reduced in
comparison to a homogeneous sheet metal anode, resulting in reduced
dendrite growth (see, for example, S. W. Kim, Metals and Materials,
6 (2000), 345-349).
[0011] Binary lithium secondary metal compounds are used as the
lithium alloy, in which the secondary metal is preferably selected
from the group composed of Si, Sn, Al, Ab.
[0012] The cathode material is selected from the group composed of
CF.sub.x, transition metal oxides, transition metal sulfides,
transition metal fluorides, transition metal oxyfluorides, organic
redox-active compounds as well as sulfur and/or selenium.
[0013] The cathode material is preferably selected from CF.sub.x,
MnO.sub.2, V.sub.2O.sub.5, V.sub.6O.sub.13, FeOF, FeF.sub.3,
FeF.sub.2, S.
[0014] The electrolyte in the rechargeable nonaqueous lithium
battery is preferably in a liquid, gelatinous or solid state at
room temperature. The rechargeable nonaqueous lithium battery
preferably contains as an electrolyte an organic aprotic solvent
selected from the group composed of cyclic or acyclic ethers,
polyethers, nitriles, lactones, carbonic acid esters and/or ionic
liquids.
[0015] The electrolyte preferably contains at least one organic
aprotic solvent selected from the group composed of
tetrahydropyran, tetrahydrofuran, 1,2-dimethoxyethane, diethylene
glycol dimethyl ether, acetonitrile, adiponitrile, malodinitrile,
glutaronitrile, .gamma.-butyrolactone and imidazolium salts.
[0016] The electrolyte of the rechargeable nonaqueous lithium
battery may preferably contain LiSCN and at least one other
conductive salt.
[0017] The additional conductive salt is preferably selected from
the group composed of LiPF.sub.6, lithium fluoroalkyl phosphates,
LiBF.sub.4, imide salts, LiOSO.sub.2CF.sub.3, methide salts,
LiClO.sub.4, lithium chelatoborates, lithium fluorochelatoborates,
lithium chelatophosphates, lithium fluorochelatophosphates and/or
lithium halides.
[0018] The electrolyte of the rechargeable nonaqueous lithium
battery may contain organic polymers selected from the group
composed of polyethylene oxide, polyacrylonitrile, polyvinylidene
fluoride or any mixtures thereof.
[0019] The LiSCN is present in the electrolyte in the rechargeable
nonaqueous lithium battery in a concentration of 0.01 to 15 wt
%.
[0020] The LiSCN is preferably present in the electrolyte in a
concentration of 1 to 10 wt %.
[0021] The invention also relates to an electrolyte for use in
rechargeable nonaqueous lithium batteries, in which lithium
rhodanide is contained as an electrolyte component.
[0022] The LiSCN is preferably present in the electrolyte in a
concentration of 0.01 to 15 wt %.
[0023] The invention relates in particular to the use of LiSCN as a
redox shuttle compound in electrolytes of rechargeable nonaqueous
lithium batteries.
[0024] It has been discovered that LiSCN oxidizes when a potential
of approximately 3.4 V vs. Li/Li.sup.+ is exceeded, and is reduced
in the subsequent reductive branch. Surprisingly, this reaction is
reversible: three cycles which illustrate this are shown in FIG. 1.
The special advantage of LiSCN is that the LiSCN itself is a
strongly dissociating lithium salt and therefore can be used as an
Li electrolyte. It is therefore not necessary in principle to use
another lithium salt having a conductive salt function in addition
to LiSCN.
[0025] The electrolyte may be present in liquid, gelatinous or
solid form. In addition to lithium rhodanide, the electrolyte may
contain organic aprotic solvents, for example carbonic acid esters
(dimethyl carbonate, diethyl carbonate, ethylmethyl carbonate,
propylene carbonate, ethylene carbonate), cyclic or acyclic ethers
(dibutyl ether, tetrahydropyran or tetrahydrofuran), polyethers
(1,2-dimethoxyethane or diethylene glycol dimethyl ether), as well
as nitriles (acetonitrile, adiponitrile, malodinitrile,
glutaronitrile) and lactones (.gamma.-butyrolactone), ionic liquids
(e.g., imidazolium salts), additional lithium salts (e.g.,
LiPF.sub.6, lithium fluoroalkyl phosphates, LiBF.sub.4), imide
salts (e.g., LiN(SO.sub.2CF.sub.3).sub.2), LiOSO.sub.2CF.sub.3,
methide salts (e.g., LiC(SO.sub.2CF.sub.3).sub.3), LiClO.sub.4,
lithium chelatoborates (e.g., LiBOB), lithium fluorochelatoborates
(e.g., LiC.sub.2O.sub.4BF.sub.2), lithium chelatophosphates (e.g.,
LiTOP) and lithium fluorochelatophosphates (e.g.,
Li(C.sub.2O.sub.4).sub.2PF.sub.2), lithium halides (LiCl, LiBr,
LH), additives (e.g., vinylene carbonate) and/or polar polymers
(e.g., polyethylene oxide, polyacrylonitrile, polyvinylidene
fluoride) in any mixture.
[0026] The LiSCN is present in the electrolyte in a concentration
of 0.01 to 15%, particularly preferably 1 to 10%.
[0027] FIG. 1 shows a cyclovoltagram of an electrolyte with 0.1 M
LiSCN in 1M LiPF.sub.6/EC:DMC (1:1 by weight) and a Pt electrode,
recorded with a rate of advance of 100 mV/s in the scanning range
of 3.0-4.0 V vs. Li/Li.sup.+.
* * * * *