Note: Descriptions are shown in the official language in which they were submitted.
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METHOD FOR PRODUCING A SILICON-CARBON ANODE AND SILICON-CARBON
ANODE OBTAINABLE BY THE METHOD
The invention relates to a method for producing a silicon-carbon anode and a
silicon-
carbon anode obtainable by the method.
Rechargeable lithium batteries have become a ubiquitous power source for
mobile
electronic devices. They are used in hybrid and electric vehicles and are an
important part
of energy storage solutions for renewable energies. To meet the ever-
increasing energy
demands of these applications, new electrode materials are needed that
increase the
energy density beyond currently available lithium batteries.
Secondary lithium-ion batteries are particularly attractive energy storage
devices with high
gravimetric and volumetric capacity and the ability to deliver a high output.
They have
become ubiquitous power sources for electric and hybrid electric vehicles.
This has led to
an intense interest in developing battery electrodes with high gravimetric and
volumetric
capacity to improve the energy density of the current generation of lithium
batteries. The
present application deals with specific anode materials that promise increased
capacity.
Lithium metal is the best anode material from the point of view of energy
density. However,
the electrodeposition of dendritic lithium can cause a short circuit during
charging, which
raises significant safety concerns for lithium-metal anodes. The most common
material
used for commercial secondary lithium-ion battery anodes is graphite, which
can
intercalate a maximum of one lithium per six carbon atoms. The volumetric
expansion
during lithium intercalation between the planar graphite layers is slightly
more than 10%,
resulting in high reversibility and stable capacity under repeated cycles.
Nevertheless, the
theoretical capacity of graphite is low compared to other potential anode
materials, such
as the lithium alloys of silicon or tin, which limits the power density.
Silicon is a promising alternative to high capacity graphite anodes. It has a
low discharge
potential (¨ 370 mV vs. Li/Li), which makes it suitable for high power
applications in
conjunction with common cathode materials such as LiCo02 or LiMn204. Abundant
and
non-toxic, it can be alloyed with up to 4.4 lithium atoms per silicon atom.
The theoretical
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capacity of the fully lithiated alloy Li4.4Si is 4212 mAhg-1, which is an
order of magnitude
higher than graphite. However, the commercial use of silicon in lithium cells
is limited by
the low cycle stability of silicon. The large volume change during lithium
intercalation leads
to high internal stresses, pulverization of the electrode, and subsequent loss
of electrical
contact between the active material and the current collector. However, this
challenge can
be overcome by silicon nanostructures that allow for easy strain relaxation to
counteract
fragmentation of the electrode and that may offer the additional benefits of
short lithium
diffusion distances and enhanced mass transport.
Lithium batteries generally consist of electrochemical cells connected in
parallel or in
series to achieve the desired current and voltage characteristics. Each cell
contains a
positive electrode (cathode) and a negative electrode (anode), separated by an
electrically insulating but lithium ion permeable separator. Ion conduction
takes place by
means of an electrolyte. The anode and cathode are connected to each other by
means
of an external circuit. During charging, electrons flow from the cathode to
the anode
through the external circuit, while lithium ions deintercalate from the
cathode and migrate
through the electrolyte to the anode to maintain charge neutrality. With a
silicon anode,
the lithium ions are alloyed with the silicon and the anode expands until it
reaches the
desired charge level. Discharge is simply the reverse of this process. The
anode
undergoes a volume contraction as lithium ions are released. The ions migrate
back
through the electrolyte and are intercalated at the cathode, while the
electrons move
through the external circuit to the cathode, performing useful work as they
go.
Particle-based anodes, in which electrochemically active silicon nanoparticles
are mixed
with conductive additives and binders, have the advantage that the often
simple particle
syntheses are easily scalable. The capacity of particulate anodes containing
conductive
additives and Si-based composite nanoparticles increases with increasing
silicon content.
Cycle stability can be improved by reducing the particle size. Most research
in silicon
composite anodes is focused on carbon matrices since carbon is abundant, its
chemistry
is well understood, and carbon has advantages over other possible matrix
materials. For
example, carbon is highly conductive, enabling efficient electron transport,
and is also
light and ductile, allowing it to accommodate the volume expansion of the
active material.
Silicon-carbon composite materials are typically made by mechanical milling of
the active
and matrix materials or by pyrolysis of carbon and silicon precursors (special
case) to
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obtain silicon in a carbonaceous matrix. The uniform carbon deposition during
pyrolysis
or prolonged ball milling in many composites results in close contact between
carbon and
silicon. In particular, it is known that silicon-carbon composite materials
can be produced
by pyrolysis of organic starting materials mixed with nanoparticulate silicon
or by direct
pyrolysis of organosilicon starting materials. For example, nanocomposites
with different
polymers as the carbon source have been reported. Silicon-carbon composite
materials,
which are produced by pyrolysis and are used as anode material in lithium-ion
batteries,
are exemplified in US 2016/0365567 Al, US 2018/287129 Al, W02021/009031 Al, US
10673062 BI, US 11114660 BI, US 2022/0013782 Al, and US 2021/0384495 Al. What
these processes have in common is that the prepolymer forms a porous carbon
structure
during pyrolysis. The disadvantage of the electrodes produced in this way has
hitherto
been a high degree of roughness of the electrodes obtained by pyrolysis, which
leads to
a high failure rate of the cells as a result of defects in the separator area,
particularly in
cyclic operation.
It is now the object of the invention to reduce the roughness of the silicon-
carbon anode
obtained by pyrolysis.
According to a first variant, this object is achieved by the method for
producing a silicon-
carbon anode with an active coating made of a silicon-carbon composite
material. The
method comprises the following steps:
al) producing a pyrolyzable coating on a current collector by applying a
mixture which
comprises a carbonaceous and pyrolyzable component, a conductive additive, and
particles of an active material,
wherein the active material is silicon or a silicon-containing compound, and
the particles are present in at least 3 different fraction sizes determined by
means
of laser diffraction particle size analysis (LD) according to ISO 13320, of
which
a first fraction of the particles has the following particle size
distribution:
mean diameter D5Om = 3 pm to 8 pm
diameter D9Om = 1.5 x D5Om to 3 x D50m,
a second fraction of the particles has the following particle size
distribution:
mean diameter D5OT = 0.2 x D5Om to 0.25 x D5Om
diameter D9OT = 1.5 x D5OT to 3 x D5OT and
a third fraction of the particles has the following particle size
distribution:
mean diameter D500 = 0.4 x D5Om to 0.45 x D5Om
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diameter D900 = 1.5 x D500 to 3 x D500
wherein the following applies to the relative ratio of the particle numbers of
the
three fractions:
nT = 1.9 x nm to 2.1 x nm
nT = 0.9 x nm to 1.1 x nm
where
nm = number of first fraction particles in a specified volume of active
coating
nT = number of second fraction particles in the same volume of active coating
no = number of third fraction particles in the same volume of active coating;
and
b1) pyrolysis of the coating.
The manufacturing process for the silicon-carbon anode accordingly provides
for the
application of a mixture containing a pyrolyzable, carbon-containing component
which is
converted into a carbon-containing matrix by pyrolysis. The mixture also
contains at least
particles of the active material (silicon or a silicon compound) as well as a
conductive
additive. In addition to the three essential ingredients mentioned, other
components can
optionally be present in the mixture. The mixture is applied to the current
collector of the
later anode and then pyrolysis takes place in a manner known per se, which
leads to the
formation of the active coating on the current collector. The active coating
thus consists
of a pyrolytically produced silicon-carbon composite material. The special
feature of the
method is that three different batches (or fractions) of particles of the
active material are
added to the mixture. The three fractions differ in their particle size
distribution, wherein
the particle sizes of the individual fractions are precisely matched to one
another in such
a way that the density of the active coating is increased. This is accompanied
by a
reduction in the roughness of the surface of the pyrolytically produced active
coating of
the anode.
Using laser diffraction particle size analysis (LD) according to ISO 13320,
the particle
sizes of the three added fractions of the active material can be determined.
The equivalent
diameter of a non-spherical particle corresponds to the diameter of a
spherical particle
that has the same properties as the non-spherical particle under
investigation. A first
fraction of the particles has the following (volume-related) particle size
distribution: mean
diameter D5Om = 1 pm to 10 pm and diameter D9Om = 1.5xD5Om to 3x D50m. The
particles
of the first fraction have a significantly higher mean diameter D5Om than the
particles of
Date Recue/Date Received 2023-06-28
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the second and third fractions. The mean particle diameter D50m is preferably
in the range
from 3 pm to 8 pm, in particular in the range from 4 pm to 6 pm. D90m is
preferably 1.5 x
D50m to 2 x D50m, especially 1.5 x D50m.
The second added fraction of the particles has the following particle size
distribution:
mean diameter D50T = 0.2 x D50m to 0.25 x D50m and diameter D90T = 1.5 x D50T
to 3 x
D50T. In other words, the mean diameter of the particles of the second
fraction is only 0.2
to 0.25 times the mean diameter of the particles of the first fraction. Even
if the particles
of the first fraction compactly abut one another in the active coating, the
smaller particles
of the second fraction can still occupy a place in the resulting tetrahedral
voids of the
compact arrangement. D90T is preferably 1.5 x D50T to 2 x D50T, in particular
1.5 x D50T.
The particles of the third fraction, which are slightly larger compared to the
second
fraction, have the following particle size distribution: mean diameter D500 =
0.4 x D5Om to
0.45 x D5Om and diameter D90o = 1.5 x D50o to 3 x D50o. In other words, the
mean
diameter of the particles of the third fraction is only 0.4 to 0.45 times the
mean diameter
of the particles of the first fraction. Even if the particles of the first
fraction compactly abut
one another in the active coating, the smaller particles of the third fraction
can still occupy
a place in the resulting octahedral voids of the compact arrangement. D90o is
preferably
1.5 x D50o to 2 x D50o, in particular 1.5 x D50o.
In a specific volume of the active coating, there is a defined number nm of
particles of the
first fraction. The number of particles nm of the first fraction in turn
determines the number
of particles nT of the second fraction and the number of particles no of the
third fraction.
The following relationship applies: nT = 1.9 x nm to 2.1 x nm and nT = 0.9 x
nm to 1.1 x nm.
In the specified volume, the number of particles in the second fraction is
therefore 1.8 to
2.1 times the number of particles in the first fraction and the number of
particles in the
third fraction is 0.9 to 1.1 times the number of particles in the first
fraction. Overall, a
particularly dense active coating can be achieved in this way, the roughness
of which is
reduced.
The silicon-containing compound may preferably be Si, SiC, SiOx, or SiN. The
mixture
can contain particles that consist of the same active material. However, it is
also
conceivable that particles with a different active material are used. For
example, the active
material of the individual fractions can differ from one another. However, it
is also possible
Date Recue/Date Received 2023-06-28
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to use different active materials within a fraction, provided they meet the
criteria set for
the fraction for the mean diameter D50 and the diameter D90.
The mixture for application in step al ) or the active coating contains a
conductive additive.
The conductive additive can be a conductive carbon black and/or a carbon-based
conductive material. Conductive carbon blacks are preferred. Conductive
additives are
well-known additives for lithium-ion batteries. Conductive carbon black (also
known as
conductive industrial soot, conductivity black, and carbon black) is a black
specialty
chemical available as a powder. It is manufactured using strictly controlled
processes and
contains more than 95% of pure carbon. Conductive carbon black has widely
ramified
aggregates that ensure electrical conductivity in the application. The shape
of the
aggregates can vary, and a distinction is made between spherical, elliptical,
linear, and
branched aggregates. Conductive carbon blacks with linear and branched
aggregates are
particularly preferred because they have higher electrical conductivity and
can be
dispersed more readily. Conductive carbon blacks are produced, among other
things, by
the furnace black method and by thermal cracking, such as the acetylene black
method.
Carbon-based conductive materials comprise carbon nanotubes (CNT) and
graphene.
Organic polymers such as, for example, polyvinyl alcohols, polyacrylates, and
polyvinylamides can be used as carbon-containing and pyrolyzable components.
The
mixture may also contain a binder or a solvent.
The mixture applied preferably has the following composition:
1 to 95% by weight of particles of silicon or a silicon-containing compound
(total across
all fractions), preferably 40 to 90% by weight;
0.01 to 15% by weight of conductive additive, preferably 0.5 to 5% by weight;
0.1 to 30% by weight of the carbonaceous and pyrolyzable component, preferably
1 to
20% by weight;
optionally, 0 to 20% by weight of a solvent;
optionally, 0 to 5% by weight of a binder; and
less than 1% by weight of impurities.
The percentages are based on the total weight of the mixture. All percentages
add up to
100% by weight.
In step bl ) of the method, the applied coating is converted into the desired
silicon-carbon
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composite material by pyrolysis and forms the anode. The composite material is
formed
in the course of the thermochemical conversion of the mixture of substances.
Pyrolysis
preferably takes place in an oxygen-free atmosphere and at a temperature in
the range
from 200 C to 1000 C, preferably from 250 C to 900 C.
A silicon-carbon anode with an active coating of a silicon-carbon composite
material is
obtainable by the method, wherein the silicon-carbon composite material
comprises the
following components:
(i) a pyrolytically produced carbonaceous matrix;
(ii) a conductive additive; and
(iii) particles of an active material, wherein the active material is silicon
or a silicon-
containing compound and the particles are present in at least 3 different
fraction sizes
determined by means of laser diffraction particle size analysis (LD) according
to ISO
13320, of which
a first fraction of the particles has the following particle size
distribution:
mean diameter D5Om = 1 pm to 10 pm
diameter D9Om = 1.5 x D5Om to 3 x D5Om
a second fraction of the particles has the following particle size
distribution:
mean diameter D5OT = 0.2 x D5Om to 0.25 x D5Om
diameter D9OT = 1.5 x D5OT to 3 x D5OT and
a third fraction of the particles has the following particle size
distribution:
mean diameter D500 = 0.4 x D5Om to 0.45 x D5Om
diameter D90o = 1 .5 x D50o to 3 x D50o
wherein the following applies to the relative ratio of the particle numbers of
the three
fractions:
nT = 1.9 x nm to 2.1 x nm
nT = 0.9 x nm to 1.1 x nm
where
nm = number of first fraction particles in a specified volume of active
coating
nT = number of second fraction particles in said volume of active coating
no = number of third fraction particles in said volume of active coating.
According to a second variant, the object mentioned above is achieved by the
method for
producing a silicon-carbon anode with an active coating made of a silicon-
carbon
composite material. For this purpose, said method comprises the following
steps:
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a2) producing a pyrolyzable coating on a current collector by applying a
mixture
containing a carbonaceous and pyrolyzable component, a conductive additive,
and
particles of silicon or a silicon-containing compound;
b2) pyrolysis of the coating; and
c2) applying compensating particles made of an active material to the
active coating
resulting from step b2), wherein the active material is selected from the
group
consisting of graphite, graphene, silicon, and silicon-containing compounds
and
the compensating particles have a mean diameter D50 of 5 pm to 20 pm, wherein
the mean diameter D50 is determined using laser diffraction particle size
analysis
(LD) according to ISO 13320.
The manufacturing method for the silicon-carbon anode according to the second
variant
thus provides for the application of a mixture containing a pyrolyzable,
carbon-containing
component which is converted into a carbon-containing matrix by pyrolysis. The
mixture
also contains at least particles of the active material (silicon or a silicon
compound) as
well as a conductive additive. In addition to the three essential ingredients
mentioned,
further components can optionally be present in the mixture. The mixture is
applied to the
current collector of the later anode and then pyrolysis takes place in a
manner known per
se, which leads to the formation of a coating on the current collector. This
coating thus
consists of a pyrolytically produced silicon-carbon composite material. The
special feature
of the method is that the relatively rough coating obtained through pyrolysis
is then leveled
by applying particles of an active material. The particle size is chosen so
that applied
compensating particles can fill depressions in the surface of the
pyrolytically produced
coating. As a result, the surface is smoothed so that the roughness of the
surface of the
pyrolytically produced active coating of the anode is reduced.
The compensating particles used in step c2) have a mean diameter D50 of 5 pm
to 20
pm, preferably 8 pm to 12 pm, wherein the mean diameter D50 is determined
using laser
diffraction particle size analysis (LD) according to ISO 13320. It has been
shown that this
particle size is particularly suitable for smoothing the rough surface of the
coating
produced by pyrolysis.
The silicon-containing compound of the particles or compensating particles can
preferably
be Si, SiC, SiOx, or SiN.
Date Recue/Date Received 2023-06-28
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The compensating particles can consist of the same active material as the
particles
already present in the coating. However, it is also conceivable that the
compensating
particles consist of a different active material. However, it is also possible
to use
compensating particles made from different active materials, provided they
meet the
criterion set for the mean diameter D50.
According to a preferred variant of the method, the compensating particles
made of the
active material are applied in the form of a paste. A paste is a solid-liquid
mixture
(suspension) having a high solids content. Pastes are no longer flowable, but
spreadable.
Application of the paste is particularly easy to implement in terms of process
engineering.
The paste can be in the form of an aqueous suspension, for example. In
addition to the
compensating particles from the active material, the paste can contain other
components,
such as conductive additives and binders.
The mixture for application in step a2) or the coating produced in step b2)
contains a
conductive additive. Likewise, the paste with the compensating particles can
contain a
conductive additive. The conductive additive can be a conductive carbon black
and/or a
carbon-based conductive material. Conductive carbon blacks are preferred.
Conductive
additives are well-known additives for lithium-ion batteries. Conductive
carbon black (also
known as conductive industrial soot, conductivity black, and carbon black) is
a black
specialty chemical available as a powder. It is manufactured using strictly
controlled
processes and contains more than 95% of pure carbon. Conductive carbon black
has
widely ramified aggregates that ensure electrical conductivity in the
application. The
shape of the aggregates can vary, and a distinction is made between spherical,
elliptical,
linear, and branched aggregates. Conductive carbon blacks with linear and
branched
aggregates are particularly preferred because they have higher electrical
conductivity and
can be dispersed more readily. Conductive carbon blacks are produced, among
other
things, by the furnace black method and by thermal cracking, such as the
acetylene black
method. Carbon-based conductive materials comprise carbon nanotubes (CNT) and
graphene.
Organic polymers such as, for example, polyvinyl alcohols, polyacrylates, and
polyvinylamides can be used as carbon-containing and pyrolyzable components.
The
mixture may also contain a binder or a solvent.
Date Recue/Date Received 2023-06-28
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The mixture applied from step a2) preferably has the following composition:
1 to 95% by weight of particles of silicon or a silicon-containing compound,
preferably 40
to 90% by weight;
0.01 to 15% by weight of conductive additive, preferably 0.5 to 5% by weight;
0.1 to 30% by weight of the carbonaceous and pyrolyzable component, preferably
1 to
20% by weight;
optionally, 0 to 20% by weight of a solvent;
optionally, 0 to 5% by weight of a binder; and
less than 1% by weight of impurities.
The percentages are based on the total weight of the mixture. All percentages
add up to
100% by weight.
In step b2) of the method, the applied coating is converted into the desired
silicon-carbon
composite material by pyrolysis and forms the anode. The composite material is
formed
in the course of the thermochemical conversion of the mixture of substances.
Pyrolysis
preferably takes place in an oxygen-free atmosphere and at a temperature in
the range
from 200 C to 1000 C, preferably from 250 C to 900 C.
Preferred refinements of the invention will be apparent from the other
features mentioned
in the dependent claims and from the following description.
The various embodiments of the invention mentioned in this application can be
combined
with one another, unless stated otherwise in an individual case.
The invention is explained below in exemplary embodiments with reference to
the
associated drawings. Wherein:
Figure 1 shows a schematic structure of a rechargeable lithium-ion
battery.
Figure 2 shows a flowchart for the production method according to the
invention
of a silicon-carbon anode according to a first variant.
Figure 3 shows a flowchart for the production method according to the
invention
of a silicon-carbon anode according to a second variant.
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Figure 1 shows a highly schematic sectional view of the basic structure of a
rechargeable
lithium-ion battery 10. The lithium-ion battery 10 includes a positive
electrode (cathode
12) and a negative electrode (anode 14), which are separated from one another
by an
electrically insulating but lithium ion permeable separator 16. Ion conduction
takes place
by means of a liquid electrolyte. The anode 14 and cathode 12 are connected to
each
other by means of an external circuit. During charging, electrons flow from
the cathode 12
to the anode 14 through the external circuit, while lithium ions deintercalate
from the
cathode 12 and migrate through the electrolyte to the anode 14 to maintain
charge
neutrality. Discharge is simply the reverse of this process. The anode 14
undergoes a
volume contraction as lithium ions are released. The ions migrate back through
the
electrolyte and are intercalated at the cathode 12, while the electrons move
through the
external circuit to the cathode 12, performing useful work as they go (load
20).
The anode 14 is a silicon-carbon anode and, according to the exemplary
embodiment,
contains silicon particles embedded in an electrically conductive carbon
matrix.
First variant of the production method
The silicon-carbon anode is produced using a pyrolytic method, the method
steps of which
are illustrated in FIG. 2 using an exemplary embodiment.
In step S100 of the method, a mixture is produced of silicon particles,
conductive additive,
a carbon-containing and pyrolyzable component, and a solvent. For this
purpose, the
ingredients can be mixed with one another using conventional mechanical
methods. The
aim is to obtain a mixture with the most homogeneous distribution of the
components
possible.
When preparing the mixture, three different fractions of silicon particles are
used. A first
fraction contains particles with a mean diameter D5Om of 5 pm and a diameter
D9Om of 9
pm. The second fraction contains particles with a mean diameter D5OT of 1 pm
and a
diameter D9OT of 2 pm. The third fraction contains particles with a mean
diameter D50o
of 2 pm and a diameter D90o of 4 pm. The proportions of the fractions are
measured in
such a way that the number of particles in the first and third fractions is
the same and
twice as many particles are present in the second fraction compared to the
number of
particles of the first fraction in the mixture.
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Water is used as the solvent, wherein the conductive additive is a conductive
carbon black
and the pyrolyzable component is a polyvinyl alcohol. The mixture contains 50%
by weight
of silicon particles or particles of silicon or a silicon-containing compound,
25% by weight
of the pyrolyzable component, 20% by weight of water and 5% by weight of
conductive
additive.
In step S110, the homogeneous mixture produced is applied to a current
collector. The
current collector can be a metal foil, for example. Common mechanical coating
techniques
can also be used for this method step. Pastes can be applied, for example, by
roll coating,
thermal spraying, slot coating, spray coating, or knife coating.
In step S120, the coated substrate is heated such that the carbonaceous and
pyrolyzable
component is thermally decomposed into carbon. Accordingly, the process
conditions
necessary for the pyrolysis of the respective component prevail in this method
step. This
is usually a low-oxygen or oxygen-free atmosphere and temperatures above 200
C. At
the end of the pyrolysis and after cooling, the silicon-carbon anode obtained
in this way
is available for the further method steps in the production of lithium-ion
batteries.
Second variant of the production method
Figure 3 illustrates the production of a silicon-carbon anode according to
another variant
of the method in a flow chart.
In step S200 of the method, a mixture is produced of silicon particles,
conductive additive,
a carbon-containing and pyrolyzable component, and a solvent. For this
purpose, the
ingredients can be mixed with one another using conventional mechanical
methods. The
aim is to obtain a mixture with the most homogeneous distribution of the
components
possible.
Water is used as the solvent, the conductive additive is a conductive carbon
black, and
the pyrolyzable component is a polyvinyl alcohol. The mixture contains 50% by
weight of
silicon particles, 25% by weight of the pyrolyzable component, 20% by weight
of water,
and 5% by weight of conductive additive.
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In step S210, the homogeneous mixture produced is applied to a current
collector. The
current collector can be a metal foil, for example. Common mechanical coating
techniques
can also be used for this method step. Pastes can be applied, for example, by
roll coating,
thermal spraying, slot coating, spray coating, or knife coating.
In step S220, the coated substrate is heated such that the carbonaceous and
pyrolyzable
component is thermally decomposed into carbon. Accordingly, the process
conditions
necessary for the pyrolysis of the respective component prevail in this method
step. This
is usually a low-oxygen or oxygen-free atmosphere and temperatures above 200
C.
In step S230 of the method, a paste is prepared from silicon particles or
particles of silicon
or a silicon-containing compound (as compensating particles), a conductive
additive, a
binder, and a solvent. For this purpose, the ingredients can be mixed with one
another
using conventional mechanical methods. The aim is to obtain a mixture with the
most
homogeneous distribution of the components possible.
The compensation particles have a mean diameter D50 of 10 pm and are made of
silicon.
Water is used as the solvent, and the conductive additive is a conductive
carbon black.
The paste contains 80% by weight of silicon particles, 15% by weight of water,
and 5%
by weight of conductive additive.
In a step S240, the paste is applied to the coating produced in step S200.
Common
mechanical coating techniques can also be used for this method step. Pastes
can be
applied, for example, by roll coating, thermal spraying, slot coating, spray
coating, or knife
coating.
After the paste has dried, the active coating of the silicon-carbon anode is
complete and
the anode obtained in this way is available for the further method steps in
the production
of lithium-ion batteries.
Date Recue/Date Received 2023-06-28
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List of reference numerals
lithium-ion battery
12 cathode
5 14 anode
16 separator
load
S100 - S120 method steps according to a first variant
S200 - S240 method steps according to a second variant
Date Recue/Date Received 2023-06-28
