Dendrite Prevention in EV Batteries

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.

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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.

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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.

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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.

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Lithium battery with high energy density and improved cycle life by using a lithium-silicon composite negative electrode. The battery has a lithium-silicon composite negative electrode active material with elemental lithium and a lithium-silicon alloy. The battery also has a protective layer on the negative electrode to suppress side reactions and lithium plating. During charging, the battery is stopped at a lower cutoff voltage where no lithium is deposited on the negative electrode. This prevents dendrite formation and improves cycle life.

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Low cost, reinforced solid polymer electrolytes for lithium-ion batteries that provide improved mechanical, electrochemical, and thermal stability compared to existing solid electrolytes. The electrolyte is made by coating a porous substrate with a fluoropolymer-ionic liquid-lithium salt solution on one side and a fluoropolymer-LLZO solution on the other side. The coated substrate is then dried and cured to form the solid electrolyte. The reinforced electrolyte has better ionic conductivity, lower dendrite growth, and higher thermal stability than pure solid polymer electrolytes.

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Lithium-ion battery with improved cycling life, energy density, and safety by mixing single crystal and polycrystal positive electrode materials in separate cells. The battery has a bare cell cavity with separate cells containing either a single crystal low-nickel positive electrode or a polycrystal high-nickel positive electrode. This allows leveraging the shrinkage property of polycrystal high-nickel materials at high charge levels to reduce stress on the negative electrode and prevent lithium plating. The single crystal low-nickel materials mitigate issues of gas production, safety, and storage degradation at high charge levels.

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Composite electrolytes for lithium-ion batteries with improved stability against dendrite growth and resistance to cracking when used with high-capacity lithium metal anodes. The composite electrolytes have a high volume fraction of inorganic solid electrolyte embedded in an organic polymer matrix. The inorganic component provides ionic conductivity while the polymer prevents dendrite growth and cracks. The composite electrolytes have fracture strengths between 5-250 MPa. The inorganic material can be a lithium-stuffed garnet oxide or antiperovskite oxide. The organic polymer can be entangled with a surface species on the inorganic particles. The composite electrolytes prevent dendrite formation and cycling at high current densities without cracking compared to pure organic electrolytes.

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Coatings for battery separators and other porous substrates that improve safety and performance. The coatings contain a polymeric binder, heat-resistant particles, and optional components like cross-linkers, shutdown agents, adhesion agents, friction-reducing agents, and thickeners. The coatings provide better heat resistance, dendrite blocking, compression resistance, adhesion, friction reduction, and shutdown performance compared to uncoated separators. The coatings can be applied to battery separators to improve safety and performance, particularly during abuse conditions like overcharge and overdischarge.

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Battery pack design that maintains optimal pressure inside the battery cells to improve lifespan and performance. The battery pack has a housing with movable rigid plates and compression springs that axially compress the battery chamber when closed. This pressurizes the cells. When pressure rises, the plates expand the chamber to prevent rupture. The springs are shape memory alloys that bias the plates closed. This allows automated pressure control for lithium metal batteries to prevent dendrite growth.

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Lithium battery separator that combines the benefits of polymer separators and solid ceramic electrolytes for improved battery performance. The separator is a three-layer structure with ceramic electrolyte coatings on either side of a polymer separator. The ceramic layers, made of materials like lithium aluminum germanium phosphate (LAGP), provide high ionic conductivity, stability, and prevent dendrite formation. The polymer separator provides flexibility and mechanical strength. The hybrid separator shows better electrolyte uptake, ionic conductivity, interface stability, cycle life, and voltage polarization compared to regular polymer separators.

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Lithium metal composite electrode material for lithium metal batteries with improved cycle stability and reduced dendrite formation compared to conventional lithium metal electrodes. The composite electrode material has a lithium-containing conductive layer grown in situ on the surfaces of lithium metal particles. This layer isolates the lithium metal from the electrolyte to reduce irreversible reactions and dendrite growth. The layer includes an inorganic lithium compound and lithium alloy. The layer serves as a 3D framework structure that coats the lithium metal particles. This framework reduces volume expansion and dendrite formation during cycling. The composite electrode material is prepared by mixing lithium metal, a metal compound, and conductive carbon, then heat treating to grow the in situ layer.

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Charging method and battery management system for electric vehicle batteries that balances charging speed and safety. The method involves determining a negative electrode potential safety threshold based on factors like state of charge, temperature, and health. During charging, the request current is adjusted based on the negative electrode potential and safety threshold to improve speed while preventing lithium plating.

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Lithium-ion battery with improved energy density, cycle life, and safety by optimizing the negative electrode structure. The battery has a laminated composite negative electrode with a sequence of lithiophilic, main body, and lithiophobic layers on the current collector. This sequence reduces dendrite growth and improves cycle life. The ratio of negative to positive capacity is kept less than 1 to boost overall energy density.

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A system to mitigate degradation of secondary batteries used in devices like electric vehicles and energy storage systems. The system monitors battery usage and identifies factors contributing to battery degradation. Based on the degradation factors, it optimizes battery charging and discharging to suppress battery degradation. This involves techniques like temperature management, current limits, and capacity balancing to prevent issues like capacity loss, cracking, and lithium plating. By tailoring battery operation to the specific degradation mechanisms, it aims to extend battery life compared to generic charge/discharge profiles.

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A nonaqueous secondary battery with a stacked separator structure that provides improved performance and reliability compared to using a single separator material. The battery has separators with different pore sizes between the electrodes. This allows optimizing ionic conductivity and electrode insulation properties separately. The stacked separators prevent direct electrode contact, reduce whisker growth, and block deposit buildup. The separator stack also resists shape change in flexible batteries.

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Battery cell force management system to optimize performance of rechargeable battery packs, like solid-state pouch cells, by maintaining proper pressure on the cells during charging, discharging, and idle states. The system uses movable end plates that apply force to the cells. Sensors measure force changes during charge/discharge and a drive mechanism adjusts plate position to compensate. This prevents capacity fade, uneven expansion, dendrite growth, etc. by keeping consistent cell stack pressure.

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A lithium metal negative electrode for lithium-ion batteries that addresses the issues of dendrite formation and interface side reactions. The electrode has a porous carbon layer with pores formed by desorbing adsorbed gas during slurry coating. This creates a 3D pore structure in the carbon layer that prevents dendrite growth and reduces side reactions compared to a smooth carbon layer. The pore structure allows lithium metal to deposit inside the pores instead of on the surface, reducing dendrite formation. The pores also provide a pathway for lithium ion transfer, mitigating side reactions.

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Monolithic ceramic electrochemical cell for solid-state lithium-ion batteries with integrated electrodes and separator. The cell has a ceramic housing with interconnected electrode spaces. The electrodes have 3D porous structures with conducting networks on sidewalls. The separator is solid ceramic. During charging, lithium forms in the anode space and ions move through the ceramic separator. This eliminates the need for liquid electrolyte and prevents dendrite growth. The 3D porous electrodes improve performance by enhancing lithium ion and electron access. The monolithic design allows hermetic sealing of the anode.

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Secondary battery with improved charge-discharge efficiency and cycle life in aqueous electrolyte batteries. The battery has composite layers on the negative and positive electrodes that contain inorganic particles and a polymer. The composite layers are joined to the electrodes but have a low peel strength between them. This allows gas generated during charge/discharge to escape outside the battery rather than accumulating inside. This prevents internal short circuits and degradation. The composite layers also have high densities to suppress electrolyte penetration and dendrite growth.

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