-
Lithium-ion batteries – electrolytes – solid & semi-solid
-
A liquid crystal-based polymer solid electrolyte composition was prepared
containing polymerizable nematic liquid crystal monomers, acrylate monomers,
ionic liquids, lithium salts, crosslinking agents and initiators.
The composition includes bifunctional liquid crystal monomers that
form continuous oriented polymer networks.
The polymerizable nematic liquid crystal monomer
1,4-[4-(6-acryloxyhexyloxy)benzoyloxy]-2-methylbenzene (C6M, top Figure),
ethylene glycol dimethacrylate (EGDMA) as acrylate monomer,
1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide
(EMIM-TFSI) as ionic liquid, lithium bis(trifluoromethanesulfonyl)imide
(LiTFSI) as lithium salt, pentaerythritol tetrakis(3-mercaptopropionate)
(PETMP) as crosslinking agent, and 1-hydroxycyclohexyl phenyl ketone as
photo-initiator were mixed (mass ratio: 20 : 40 : 15 : 15 : 10 : 0.8).
The composition was dissolved in N-methylpyrrolidone (NMP, mass ratio 1.4 : 1),
stirred (30 min), and ultrasonically dispersed (30 min). The precursor solution
was injected into a glass mold with PTFE spacers (200 μm thickness) and
UV-cured (365 nm wavelength, 20 mW/cm2, 25°C, 20 min). The resulting
film was vacuum dried (80°C, 24 h) to obtain the final
liquid crystal-based polymer solid electrolyte (LCPE).
SEM analysis reveals a porous network structure with oriented channels for
lithium ion transport (middle Figure). The surface morphology (left) is consistent with a continuous
polymer matrix with uniformly distributed pores, while the cross-sectional
view (right) exhibits interconnected channels throughout the film thickness. The
electrolyte exhibits an ionic conductivity of 2.0 × 10-3 S/cm
at 25°C.
Li/LFP cells with this electrolyte exhibit favorable cycling stability
(bottom Figure). The cells maintain a capacity retention of 99.3% after 100 cycles
and continued cycling for 1,500 cycles at 1 C charge / discharge, exhibiting
stable coulombic efficiency throughout. Li/NMC811 cells exhibit 92.9% capacity
retention after 100 cycles at 0.2 C charge / discharge.
LFP: lithium iron phosphate
LCPE: liquid crystal-based polymer electrolyte
1C RT: 1C rate at room temperature
This work illustrates how liquid crystal-based polymer electrolytes exhibit highly promising characteristics, ionic conductivity,
and electrochemical performance, without relying on very complex organic molecules or expensive raw materials.
Presumably, optimization of the NMC coating is necessary to avoid parasitic reactions at high voltages.
-
The premium version includes another two patent discussions, plus an Excel list with 50-100 commercially relevant recent patent families.
-
Lithium-ion batteries – negative electrode (excluding Li metal electrodes)
-
A silicon-based negative electrode active material with a dual-layer coating
structure was developed for all-solid-state sulfide Li-ion batteries. The material consists
of a silicon substrate with an inner coating layer and an outer coating layer,
where the Young's modulus values satisfy the relationship B > A > C
(A: silicon substrate – 28 GPa, B: inner layer – 87 GPa, C: outer layer – 16 GPa).
The inner coating layer contains ion-conducting and electron-conducting
components (mass ratio 2 : 1 to 8 : 1). LiNbO3 was used as
the ion-conducting component (ionic conductivity:
≥10-10 S/cm), while single-walled carbon nanotubes (SWCNT) serve as the
electron-conducting component. The outer coating layer consists of
Si-doped argyrodite sulfide electrolyte and SWCNT (mass ratio 1 : 1).
Pure silicon particles (3 μm initial size) were first dispersed with
SWCNT (0.5 mass%) in water, then mixed with lithium
niobate precursors (niobium oxalate and lithium hydroxide solutions),
followed by a heat-treatment (700°C, 3 h, inert atmosphere) to form the inner
coating. The outer coating was then
applied using Si-doped argyrodite sulfide electrolyte and SWCNT in acetonitrile, followed
by a second heat treatment (500°C, 6 h, inert atmosphere).
Negative electrodes were prepared by mixing the coated silicon material
(67 mass%), Li6PS5Cl solid electrolyte
(25 mass%), flexible chloride solid electrolyte additive (LiInCl, 2.5 GPa Young's modulus', 5 mass%),
vapor-grown carbon fibers (VGCF, 2 mass%) and PTFE (polytetrafluoroethylene) binder
(1 mass%).
An SEM image (top Figure) is consistent with the formation of the dual-layer coating
structure. Cross-sectional analysis of the negative
electrode (middle Figure) demonstrates tight contact between the silicon material
and sulfide solid electrolyte, with high electrode density and minimal
porosity.
In half-cell tests, the negative electrode exhibits a first cycle efficiency of 89.3%
and variable C rate performance shown in the bottom Figure.
容量保持率(%): capacity retention (%)
循环圈数(n): cycle number (n)
This work suggests that WeLion is evaluating the use of sulfide electrolytes in combination with microscale metallurgical Si.
Key emphasis is laid on avoiding or compensating crack-formation through the mechanical characteristics of the different layers,
including through the use of LiNbO3, LiInCl, and SWCNT.
Presumably, comparably low raw materials costs for the overall negative electrode composition are a major reason for the
evaluation of this set of materials.
-
The premium version includes another two patent discussions, plus an Excel list with 50-100 commercially relevant recent patent families.
-
Lithium-ion batteries – positive electrode
-
Na- & Fe-containing Li0.85Na0.15Ni0.5Co0.2Mn0.2Fe0.1O2
positive electrode active material was prepared by dissolving lithium acetate,
sodium acetate, nickel acetate, iron acetate, cobalt acetate,
and manganese acetate in deionized water containing citric acid (1 : 1 molar
ratio of total metals to citric acid).
The mixture was stirred at 60°C until a solid gel formed, then dried at 100°C
for 12 h and at 400°C for 4 h to obtain the precursor. The precursor was calcined
at 750°C for 20 h in air atmosphere to produce the final positive electrode
active material.
It is claimed that the material exhibits significantly reduced production cost compared to
conventional NMC materials while maintaining favorable energy density, specifically a
cost reduction of 14.6% that comes with a 3.0% energy density
decrease.
In half-cell tests, the material demonstrates a discharge capacity of 196.6 mAh/g,
a first cycle efficiency of 88.5%, and a capacity retention of 95.2% after 50
cycles (0.5 C charge / 1 C discharge, 4.25 V vs. Li+/Li upper voltage limit), as compared to 193.8 mAh/g, 87.9%, and
90.7% for the Na-free comparative material, respectively.
This work illustrates that sodium and iron can be introduced into high-nickel NMC materials to reduce costs,
while maintaining favorable electrochemical performance.
-
The premium version includes another two patent discussions, plus an Excel list with 50-100 commercially relevant recent patent families.
-
Fuel cells (PEMFC / SOFC / PAFC / AEMFC) – electrochemically active materials
-
A fluorinated polymer-based catalyst layer composition was developed for
proton exchange membrane fuel cells (PEMFC) with enhanced performance under
low-humidity conditions.
The composition comprises a fluorinated polymer with cyclic ether structure
units and ion exchange groups, a carbon-supported platinum catalyst, and
solvent (water / ethanol). The fluorinated polymer exhibits
an ion exchange capacity of 1.3 milliequivalent/g dry resin and a mass ratio
to carbon support of ≈0.8 : 1.
Carbon support preparation involves treatment of carbon black with specific
surface area of 800 m2/g.
Platinum nanoparticles (average diameter : 2.4 nm,
46.9 mass% loading) were deposited on the carbon support via chemical reduction
methods.
Catalyst layer formation was achieved by coating the composition onto PTFE
(polytetrafluoroethylene) substrate, followed by drying (80°C, 10 min) and
heat treatment (150°C, 15 min, target platinum loading: 0.2 mg-Pt/cm2).
Membrane electrode assembly (MEA) fabrication involves hot pressing the
catalyst layers onto Nafion 117 membrane (170°C, 3.0 MPa, 2 min). Performance
testing under low-humidity conditions (20% relative humidity, 80°C, 2.0 A/cm2)
exhibits cell voltages of 0.55-0.57 V.
As compared to conventional compositions without cyclic ether structure units,
the optimized formulation exhibits enhanced proton conductivity of
3.17 × 10-1 S/cm at 90% relative humidity and
2.0 × 10-2 S/cm at 50% relative humidity.
This work illustrates that cyclic ether structural units in fluorinated polymers lead to improved
proton conductivity.
-
The premium version includes another two patent discussions, plus an Excel list with 50-100 commercially relevant recent patent families.
-
Triweekly patent lists for other categories (Excel files are included for premium users)
-
- Lithium metal batteries (excluding Li-S, Li-Air): XLSX
-
- Lithium-air batteries: XLSX
-
- Lithium-ion batteries – electrolytes – liquid: XLSX
-
- Lithium-ion batteries – separators: XLSX
-
- Lithium-sulfur batteries: XLSX
-
- Na-ion batteries: XLSX
-
Prior patent updates
-
2025-05-20
-
2025-04-29
-
2025-04-08
-
2025-03-18
-
2025-02-25
|
