EV Battery Electrode Material Innovations

Machining process to improve quality of electrode plates for batteries. It involves forming an indent at the boundary between the tab and unneeded portion of an electrode plate during manufacture, then detaching the unneeded portion by applying force along the indent. This prevents vertical burrs and chipping that can occur when cutting the tab. The indent is formed using a rotating roll that presses against the plate to create the indent. A separate part applies force to detach the unneeded portion along the indent.

A method for preparing a silicon monoxide composite material with improved electrical conductivity and initial coulombic efficiency compared to pure silicon monoxide for use in lithium-ion batteries. The method involves growing carbon nanotubes directly on the surface of the silicon monoxide using an in-situ catalyst. This provides a uniform carbon coating with nanotubes and a small amount of amorphous carbon that improves electrical conductivity and reduces volume variations during charging/discharging compared to adding carbon externally.

Three-dimensional lithium anode for high-capacity lithium-ion batteries that addresses the limitations of graphite anodes. The anode has a vertical structure with columnar or grid-shaped lithium deposited on a copper substrate. A conformal capping layer is deposited over the lithium to protect it and prevent dendrite growth. The vertical structure allows higher lithium loading density compared to flat graphite anodes. The capping layer prevents volume expansion and ensures stable cycling. The 3D lithium anode has higher capacity, lower weight, and better cycling compared to graphite anodes.

A positive electrode active material for lithium-ion batteries that retains its structure and capacity after repeated charge/discharge cycles. The material has a surface region with higher concentration of an additive element X compared to the interior. This reinforces the outer surface and prevents breakage of the layered structure as lithium is extracted during charging. The higher X content surface helps the material maintain its structure and capacity over cycles compared to a homogeneous composition.

Anode design for lithium-ion batteries with reduced binder decomposition during cycling. The anode has a coating layer between the active material core and the binder. The coating layer is made of a fluoropolymer like PVDF, PTrFE, PCFE, or PCTFE. This coating blocks electron transport from the core to the binder, preventing decomposition of the binder during cycling.

Active material for high capacity lithium-ion batteries with improved initial charge-discharge efficiency and cycling performance. The active material is a composite oxide with a tetragonal crystal structure represented by the general formula LiaTibNb2-2dMc+2dO2b+5+3c, where M is W or Mo and the subscripts satisfy certain constraints. This composite oxide provides high charge/discharge capacity per volume compared to traditional carbon anodes. It shows favorable initial efficiency and cycling stability in lithium-ion batteries.

Reducing volume change of battery active materials during charging/discharging by creating a porous structure inside the material particles. The method involves preparing a LiSi precursor with a specific crystal phase, then extracting Li using a solvent to form voids in the precursor. This step creates a porous active material with reduced volume change compared to non-porous materials. The specific crystal phase is Li22Si5.

Gel electrolyte for zinc-air batteries that minimizes carbonate formation, hydrogen gas buildup, and corrosion while providing high ionic conductivity. The gel electrolyte contains a red seaweed polysaccharide network with interstices filled with a concentrated solution of metal hydroxide. The high concentration of hydroxide prevents carbonate formation and hydrogen evolution. The high concentration of metal hydroxide also enhances gelation and ionic conductivity. The gel electrolyte can be used in zinc-air batteries without separators, as the gel itself physically separates the anode and cathode.

Electrode assembly for secondary batteries with improved thermal runaway resistance to prevent battery failures in abuse situations. The electrode assembly has barriers made of current collectors with low thermal conductivity in at least one electrode plate. The barrier thickness and thermal conductivity satisfy a condition of lambda over delta less than 3x107 W/(K*m2) to provide effective thermal resistance. This impedes heat spreading if a local failure occurs, reducing risk of chain reactions and thermal runaway.

Manganese oxides for lithium-ion and sodium-ion batteries with high capacity, long cycle life, and low cost. The manganese oxides have compositions containing lithium and/or sodium, like Li1.5Mn0.5O2 or Na1.5Mn0.5O2. They can be synthesized by introducing manganese, sodium, and metal precursors under specific conditions. The metal can be any element except manganese or sodium. The resulting oxides have improved performance compared to conventional manganese oxides used in batteries.

Carbon-based materials, fabrication methods, and energy storage devices with improved performance. The carbon materials have high surface area, pore size, and oxygen content. They can be made using a modified Hummers' method or a non-Hummers' method. The modified Hummers' method involves cooling the graphite and sulfuric acid mixture before oxidation. The non-Hummers' method involves adding potassium permanganate, agitating, cooling, and hydrogen peroxide. These materials can be used as active materials in lithium-ion battery electrodes, coating on lithium metal negative electrodes, or asymmetric supercapacitor electrodes.

Lithium-ion battery cathode material with improved power density and reduced moisture uptake for low-voltage applications like electric vehicles. The cathode is lithium iron phosphate (LFP) with specific dopant compositions and synthesis methods to avoid NH3 emissions and achieve target properties like high capacity, rate capability, and low temperature performance. The LFP formulation has a molar ratio of phosphate to iron around 1.00-1.05, vanadium dopant partially replacing Fe, and total non-lithium metal to phosphate ratio around 1.00-1.04. The vanadium dopant is VPO4, which has similar anions to FePO4, for higher efficiency. Optionally, cobalt co-doping is used. The synthesis involves mixing the dopants, iron phosphate, l

An active material for lithium-ion battery cathodes that improves cycle life and capacity retention compared to traditional cathode materials. The active material has a layered crystal structure with a composition of Li(Ni, Co, Mn, Mg, Al, K, Na, Ca, Si, Ti, V)O2 where some of the transition metal elements (Nb, Ta) are disproportionately enriched at the surface. This suppresses side reactions and oxygen loss during cycling, reducing capacity fade. The active material also has a specific surface area of 5-50 m2/g. The enriched surface transition metals prevent surface layer formation and improve cycle life compared to traditional cathode materials.

Negative electrode for lithium metal batteries with improved cycle life and reduced volumetric change during charging. The negative electrode has a protective layer on the lithium metal surface with particles sizes between 1-100 microns. The protective layer has a Young's modulus of 106 Pa or greater. This provides mechanical strength to prevent dendrite growth and volumetric expansion during charging. The protective layer also improves lithium deposition density compared to bare lithium metal electrodes.

An all solid state battery design to prevent short circuits in the anode during charging by controlling the resistance distribution. The battery has a coating layer with lithium titanate on the anode current collector. The coating exists in the region where the anode and cathode are opposing but is omitted in the region where they are not opposed. This helps balance charge reaction progression in both regions. In the opposed region, the coating provides a conductive path to lower anode potential. In the non-opposed region, the coating omission reduces resistance compared to the coated region. This prevents uneven charge reaction progression and minimizes short circuits in the anode.

Anode material for lithium-ion batteries that addresses the limitations of pure silicon anodes in improving battery performance. The anode is a composite made of agglomerated nanocomposites where each nanocomposite has a dendritic nanoparticle of silicon or other Group 4A element surrounded by discrete non-porous nanoparticles of the same element. The dendritic nanoparticles interconnect in the agglomerated nanocomposites to form a porous structure. This allows volume expansion of the silicon during charging without separating from the current collector. The composite anode also has improved electrical conductivity compared to pure silicon.

Electrode assembly design for batteries to improve electrolyte impregnation and reduce internal resistance. The electrode has slits in the uncoated portions along the circumference and radial direction. These slits allow electrolyte to pass through and uniformly fill the electrode stack. The slits also provide wider contact areas when bent to secure the electrode tabs. This reduces internal resistance and improves coupling strength compared to unslotted electrodes.

Lithium electrode for batteries with a protective layer to prevent dendrite growth in lithium metal anodes. The protective layer is a composite of two layers: a first layer close to the lithium metal with high ion conductivity, and a second layer further from the lithium metal with high electrical conductivity and mechanical strength. The first layer allows lithium ions to pass and prevents lithium depletion. The second layer transfers electrons to the lithium surface and prevents localized current density. The composite layer structure inhibits dendrite growth and improves battery performance compared to single-layer coatings.

Active material for high-performance lithium-ion battery negative electrodes that balances capacity, cycle life, and energy density. The active material contains both Nb2TiO7 and Nb-rich phases like Nb10Ti2O29, Nb14TiO37, and Nb24TiO64. It also has optimized particle size distribution and contains potassium and phosphorus. The Nb-rich phases improve overcharge resistance and cycle life. The potassium and phosphorus help suppress particle growth during synthesis. The particle size distribution is fine enough for good rate performance but not excessively small to prevent cracking during cycling.

Additive materials for lithium-ion batteries that prevent or reduce manganese dissolution during charging/discharging cycles. The additive materials are compounds with the general formula Mn+1AXn, where M is an early transition metal, n is 1-3, A is a group 13/14 element, and X is C or N. These MAX compounds have improved thermodynamic stability compared to manganese and can be added to lithium-ion battery cathodes to decrease manganese dissolution in the electrolyte. This improves battery performance by preventing capacity loss and structural changes caused by manganese leaching.