Metastable
orthorhombic
niobium
pentoxide
(T-Nb2O5)
with
fast
lithium
storage
capability
and
safe
operating
voltage
are
recognized
as
suitable
anode
material
for
high
power
density
lithium-ion
batteries
(LIBs).
While,
the
T-Nb2O5
also
suffers
from
low
electrical
conductivity
in
practical
applications.
In
this
work,
electrochemical
performance
of
is
enhanced
by
constructing
a
free-standing
electrode
introducing
N-doped
carbon
substrate.
The
consisting
network-structured
Nb2O5
layer
porous
cloth
(PCC)
avoids
use
binders
benefits
electron
transport.
addition,
introduction
substrate
beneficial
to
enhance
electronic
Nb2O5.
When
used
LIBs,
PCC@Nb2O5
demonstrates
excellent
long
cycle
life
rate
performance,
specific
capacity
over
150
mAh
g-1
after
3200
cycles
at
current
1000
mA
g-1.
This
strategy
electrodes
provides
new
options
obtaining
high-performance
electrodes.
Chemistry of Materials,
Год журнала:
2024,
Номер
36(11), С. 5709 - 5719
Опубликована: Май 20, 2024
Lithium-ion
batteries
for
high-power
applications
have
become
an
increasingly
important
area
of
development
as
these
devices
been
used
in
implantable
medical
devices,
where
extreme
safety
and
long
lifetimes
are
essential.
TiNb2O7
has
emerged
a
promising
candidate
to
replace
the
current
industrial
standard
Li4Ti5O12
safe
anode.
In
this
study,
we
use
combinatorial
methods
screen
effects
52
different
dopants
(M)
composition
(TiNb2)0.98M0.06O7
with
unique
elemental
dopants.
The
materials
were
studied
high
throughput
by
X-ray
diffraction
cyclic
voltammetry
reveal
performance
doped
materials.
Structural
analysis
revealed
change
lattice
parameters
dependent
on
substituent
present,
some
extremely
large
able
partially
substitute
into
Several
materials,
particularly
dopants,
show
excellent
discharge
capacities
326.7
mAh
g–1
at
room
temperature,
improvement
over
20%
undoped
material
despite
moderate
doping
levels
(2%
metals).
Many
TNO
samples
extended
cycling,
especially
37
°C.
dramatic
improvements
addition
(most
which
electrochemically
inactive)
attributed
distortions
local
structure
improving
Li
diffusion
paths,
thereby
enabling
higher
capacities,
establish
new
design
principle
optimizing
anodes.
Energy & Fuels,
Год журнала:
2024,
Номер
38(3), С. 2463 - 2471
Опубликована: Янв. 17, 2024
The
development
of
a
high-performance
anode
is
critical
for
the
design
ultrahigh-capacity
lithium-ion
batteries
to
participate
in
next-generation
energy-storage
devices.
However,
delocalization
transition
and
sluggish
reaction
kinetics
during
TiNb2O7
(TNO)
relithiation
lead
its
low
rate
performance
rapid
capacity
decay.
In
this
work,
ball-milling
method
plasma
technology
are
used
construct
TNO
nanocomposites
which
defect-rich
particles
tightly
encapsulated
by
an
amorphous
layer.
Through
structural
characterization,
electrochemical
behavior
tests,
kinetic
calculations,
increase
oxygen
vacancies
other
defects
can
optimize
electronic
structure
achieve
electron
transport
ion
migration,
dense
layer
inhibit
internal
stress
volume
expansion
electrode
cycling.
As
result,
optimized
PTNO
has
excellent
lithium
storage
with
high
347.9
mA·h·g–1
at
0.1C,
57.5
30C,
stability
1000
cycles
10C.
This
study
provides
new
perspective
on
interface
engineering
highly
reversible
durable
secondary
battery
anodes.
Advanced Functional Materials,
Год журнала:
2025,
Номер
unknown
Опубликована: Апрель 14, 2025
Abstract
Safe
fast‐charging
anodes
with
high
operating
voltage,
such
as
Li
4
Ti
5
O
12
(≈1.55
V)
and
TiNb
2
7
(≈1.65
V),
compromise
the
full‐cell
output
voltage
(2.3
to
ensure
safety,
limiting
energy
density.
Lowering
anode
potential
can
effectively
enhance
density
while
maintaining
safety;
however,
mechanisms
behind
require
further
exploration.
Here,
methods
are
proposed
lower
by
enhancing
M–L
covalent
bonding,
achieved
reducing
coordination
number,
electron‐donating
inductive
effects,
or
utilizing
pseudo‐Jahn–Teller
effect
distortion.
Using
LiLaTiO
a
model
anode,
distortion
of
TiO
6
octahedra
is
explored
show
how
it
adds
covalency
Ti–O
bonds,
lowing
(≈0.3
V).
Moreover,
bulk
exhibits
excellent
rate
performance
(181
mAh
g
−1
at
1
A
,
122
10
)
good
cycling
stability
(retention
73%
after
6000
cycles
).
NCM811//LiLaTiO
full
cell
demonstrates
exceptionally
high‐power
(118.4
C
95.6
20
C),
achieving
3.6
V,
57%
higher
than
2.3
levels
graphite‐LiFePO
systems.
These
improvements
attributed
lithium
storage
sites
low
hopping
barriers
structure
Ruddlesden–Popper
perovskite,
offering
new
insights
for
safe
anodes.
