Lithium Iron Phosphate Cathode Development for EV Battery

Battery monitoring system for accurately estimating state of charge (SOC) of a battery pack with flat OCV curve cells like LFP, using a virtual cell model and physical cell model. The virtual cell model has a more pronounced OCV curve, like NCM, to provide a definitive output of cell voltage and SOC. The physical cell model has parameters specific to the actual pack cells. By combining the definitive and indefinite outputs, a more accurate SOC estimate is generated for the pack with flat OCV cells.

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Lithium secondary battery with improved low-temperature performance by improving electrode impregnation. The battery uses a specific loading range of 450-740 mg/25 cm2 for the positive electrode with lithium iron phosphate particles. The electrolyte contains additives like compounds represented by Formulas 1-3 in a 0.1-3% range. This improves capacity expression, lifetime, and resistance at low temperatures.

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Charging method for batteries in electric vehicles that improves accuracy of state of charge (SOC) and state of health (SOH) estimation for lithium iron phosphate (LFP) batteries without disrupting normal driving patterns. The method involves calculating the exact SOC during charging by leveraging vehicle-to-grid (V2G) functionality. When the vehicle is plugged into a charging station, it first discharges to 24% SOC to accurately determine the SOC. It then charges back to full. This allows precise SOC determination without relying solely on open circuit voltage (OCV) in the flat voltage range of LFP batteries.

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Composite lithium iron phosphate (LFP) material for high-energy lithium-ion batteries with improved density and capacity. The composite LFP is prepared by coating iron phosphate and lithium sources with a mixture of carbon sources, including synthetic polymer carbon, biomass carbon (carbonized plant fibers), and carbohydrate carbon. The composite LFP has higher compaction density due to the encapsulating carbon coating. This improves the specific capacity compared to uncoated LFP. The carbon fiber coating provides better compaction while the synthetic and carbohydrate carbon sources enhance encapsulation.

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Recycling lithium battery metals using a wet processing method to extract valuable metals from cathode materials like lithium iron phosphate and ternary compounds without pre-separating the battery types. The process involves pyrolysis to convert the batteries to gases and solids, followed by gas cleaning and solid separation. The solids are treated with water to extract metal ions. This allows efficient separation and recovery of metals like lithium, nickel, manganese, and cobalt from the battery waste.

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Abstract In this study, a multiscale heterogeneous electrochemicalthermomechanical coupling model (MHETM) is proposed. A twodimensional gradient porosity electrode (U1, G2, and G3) 3D macroscopic cell are combined to realize coupled multiphysics field simulation of lithium iron phosphate (LFP) battery from microscopic particles cells. The MHETM has higher accuracy can more accurately describe the ion transport process inside active particles. results show that design optimizes diffusion path improves rate endofdischarge concentration. Meanwhile, maximum stress displacement G3 significantly lower than those U1 model, respectively. addition, thermalmechanical analysis revealed negative correlation between thermal expansion. introduction macrothermal further facilitates transport, resulting in an increase concentration maxima both models, with significant model. provides effective tool for indepth understanding complex multiphysical mechanism lithiumion batteries.

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With the popularity of electric vehicles, number used lithium iron phosphate (LiFePO 4 , LFP) batteries has increased significantly, and failure to properly dispose these endoflife power will cause serious harm environment. In this study, an environmentally friendly efficient solidphase method is proposed regenerate spent LFP cathode materials. method, crystal structure materials restored by supplementing using a source, Fe 3 + impurities in are reduced glucose, regenerated carbon coated. addition, Al introduced dope further enhance its repair effect. The test results show that doped material low electrochemical impedance, dischargespecific capacity reaches 148.59 mAh g 1 at 0.05 C multiplication rate, which about 93.38% new (NLFP). retention rate 89.02% after 500 cycles 1 rate. These data indicate doped exhibits excellent recovery cycling stability. This study provides route for recycling waste

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Battery pack with improved low temperature performance by optimizing cell placement and electrode chemistry. The pack has three regions based on temperature simulations at low temperatures. Cells are arranged with the lowest temperature cell closest to the pack walls. The lowermost cell contains a lithium iron phosphate positive electrode with a low-temperature additive containing multiple carbonyl groups. This allows better discharge capacity at low temperatures compared to regular lithium iron phosphate. The adjacent cells also have the additive, but in lower amounts. This balances capacity loss between cells at low temps.

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The rapid growth of lithium iron phosphate (LiFePO4, LFP)-based lithium-ion batteries in energy storage raises urgent challenges for resource recovery and environmental protection. In this study, we propose a novel method selective extraction the resynthesis cathodes from spent LFP batteries, aiming to achieve an economically feasible efficient recycling process. process, leaching H2SO4-H2O2 system is employed rapidly selectively extract lithium, achieving efficiency 98.72% within just 10 min. Through exploration precipitation conditions lithium-containing solution, high-purity Li2CO3 successfully obtained. recovered FePO4 are then used resynthesize cathode materials through carbon-thermal reduction method. A preliminary economic analysis reveals that disposal cost approximately USD 2.63 per kilogram, while value regenerated reaches 4.46, highlighting advantages Furthermore, with acid-to-lithium molar ratio only 0.57-just slightly above stoichiometric 0.5-the process requires minimal acid usage, offering clear benefits. Overall, work presents green, efficient, viable strategy showcas... Read More

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ABSTRACT The rapid emergence of lithiumion batteries (LIBs) to satisfy our ever increasing energy demands will result in a significant future waste problem at their end life. Lithium iron phosphate (LFP) as cathode material is now widely used LIBs with market share. It expected that there be volumes battery containing this the near future, and therefore it important develop methods for effectively repurposing LFP mitigate its impact on environment. In work we demonstrate from spent electrocatalysts oxygen evolution reaction (OER) which critical electrochemical water splitting production green hydrogen. Our study has shown recovered once immobilized onto Ni substrate reconstructs into mixed Fe/Ni oxide surface layer highly active OER. Promisingly, were cycled multiple times (up 100 cycles) showed excellent electrocatalytic performance low Tafel slope 58 mV dec 1 , overpotential values 250 310 reach 10 mA cm 2 respectively 24 h stability over 200 . This research provides potential motivation recycling companies isolate Li ion later use electrolysis technologies.

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This study presents a transformative approach to passive thermal management in lithium iron phosphate (LiFePO4) battery packs through geometrically optimized aluminum cooling structures. We investigate four distinct configurations - baseline (uncooled), unilateral side plate, inter-cell plates, and molded enclosure using experimentally validated COMSOL Multiphysics simulations under extreme 20C discharge conditions (50 A per cell). The most advanced design, featuring an mold surrounding 90% of each cell's height, achieves unprecedented 11 C reduction peak temperature (from 66 55 C) compared conventional uncooled packs, while maintaining 99.1% original power output (1107 W vs. 1118 W). performance surpasses existing methods rivals many active systems, accomplished three key innovations: 1. patented snap-fit geometry that enhances heat transfer simplifying assembly, 2. strategic material distribution reduces gradients by 32% baseline, 3. cost-effective solution adding less than $1 pack expenses. Furthermore, when combined with paraffin phase change material, the system demonstrates... Read More

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A method for charging and discharging lithium iron phosphate (LFP) batteries in segmented charge/discharge cycles to keep the charge/discharge intervals constant. During charging, the charging ends when the battery voltage reaches a predetermined end-of-charge voltage. During discharging, the discharging ends when the discharged capacity equals the previous charge capacity multiplied by the battery's Coulombic efficiency. This prevents early discharge termination due to voltage plateaus in LFP batteries.

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Lithium ion battery positive electrode composition and electrode design to enable accurate state of charge estimation and improved safety. The electrode contains a specific ratio of lithium iron phosphate, lithium iron manganese phosphate, and layered oxide-based active material particles. This mixture provides a discharge curve with a central non-plateau region between the two plateau regions. This central region allows accurate state of charge estimation compared to batteries with only plateau regions. The mixture ratio is 0.10≤x≤0.60, 0.10≤y≤0.70, 0.10≤z≤0.40, and x+y+z=1.

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Preparation method for iron phosphate precursor for lithium iron phosphate (LFP) batteries that improves product quality, reduces raw material waste, and simplifies manufacturing compared to conventional methods. The key steps are: 1) Using iron powder with specific density and particle size distribution. The powder has a lower density (2.3-2.6 g/cm3) and smaller second particle size range (10-30% of total weight) compared to conventional iron powders. 2) Titrated addition of phosphoric acid to iron powder dispersed in water, with controlled reaction temperatures, to prevent rapid heating and reaction rate issues. 3) Heat treating the precursor in air or oxygen. The titrated addition and controlled reaction temperatures prevent excess hydrogen generation, rapid heating, and reaction rate issues. The specific iron powder properties allow slower reaction rates and better control. This reduces waste, improves

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All-solid-state lithium-ion battery with improved safety and performance by using a sulfide solid electrolyte in the positive electrode, negative electrode, and separator. The battery has a positive electrode with a safety functional layer of olivine-type lithium iron phosphate between the current collector and active material. The active material itself contains a sulfide solid electrolyte along with the regular electrode material. The separator also uses the sulfide solid electrolyte. This eliminates the need for a flammable liquid electrolyte, reducing safety issues like explosion and fire. The sulfide solid electrolyte provides improved ionic conductivity compared to traditional solid electrolytes like oxides.

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<title>Abstract</title> In this study, spent lithium iron phosphate (LFP) LIBs from electric vehicles were recycled through hydrometallurgical and pyrometallurgical routes. The cathode material was characterized by X-ray diffraction (XRD), Raman spectroscopy, energy-dispersive scanning electron microscopy (SEM), inductively coupled plasma optical emission spectrometry. LiFePO₄, Fe₂O₃, FePO₄ identified as the predominant phases, Fe(OH)₃ Fe₂(PO₄)O secondary phases. Alkaline leaching found to be effective in recovering preserving structural components, such LiFePO₄. residue then used for synthesis of a novel material. Structural morphological characterization XRD, SEM revealed disordered crystalline phase -LiFe₅O₈/-Li₂FeO₃/-Fe₂O₃ with agglomerated grains irregular particle sizes. exhibited pseudocapacitor behavior, specific capacitance 3.0 F g¹ 82% retention over 250 charge/discharge cycles at current density 0.7 A ... Read More

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A low-cost, efficient method to recycle lithium iron phosphate (LFP) batteries and produce high-purity LFP precursor material for reuse in new batteries. The recycling process involves steps like acid leaching, copper electrolysis, iron oxidation, iron phosphate precipitation, and lithium carbonate precipitation. It separates and removes impurities like copper and aluminum from the LFP precursor, reducing impurity content compared to other methods.

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High-rate lithium iron phosphate (LFP) cathode material for lithium-ion batteries with improved fast charging performance. The LFP cathode material is prepared by a two-stage calcination process to nanize the particles and inhibit agglomeration, while coating them with graphene and carbon. This enhances ion and electronic conductivity for better rate performance. Nitrogen doping of the carbon further improves conductivity. The two-stage calcination prevents carbon film blow-off during high-temperature treatment. The LFP-graphene-carbon composite has high capacity at low rates and maintains good cycling stability.

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Abstract The definite lifespan of lithium iron phosphate (LiFePO 4 , LFP) batteries necessitates the advancement costeffective, naturefriendly, and productive recycling techniques for spent LFP batteries. In this study, ethylene glycol (C 2 H 6 O ), a sustainable economical small organic molecule, is employed as multifunctional hydrogenbonding donor, along with chloride (LiCl), readily accessible Li source acceptor. Together, they form novel Lisalt deep eutectic solvent (DES) through hydrogen bonding interactions. This DES directly repairs rejuvenates cathode material (SLFP) at 80 C. not only replenishes depleted in SLFP reduces adverse effects LiFe antisite defects but also establishes reducing environment that facilitates reversion degraded Fe(III) species back to their original Fe(II) state. Consequently, regenerated exhibits remarkable electrochemical behavior, delivering an initial capacity 155.6 mAh g 1 0.1 C retaining 93% its after 300 cycles 1 C. approach can be scaled up treat large quantities recovered from fully retired batteries, presenting pract... Read More

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Abstract: The rapid proliferation of electric vehicles (EVs) has significantly contributed to reducing greenhouse gas emissions and advancing sustainable transportation systems. Central the functionality these EVs are lithium-ion batteries (LiFePO4), known for their high energy density long lifespan. However, as EV market continues expand, growing issue battery waste management presents considerable environmental economic challenges. This paper provides a comprehensive overview three main types utilized in vehicles, namely, Lithium Iron Phosphate (LFP), Nickel Manganese Cobalt (NMC) aluminum (NCA) batteries. It examines challenges opportunities recycling disposal within broader context ongoing crisis. As demand clean technologies intensifies, becomes crucial ensure long-term viability renewable systems addressing resource scarcity. review explores complexities involved disposal. discusses four prominent methods that available practice 2024. advantages disadvantages each carefully evaluated discussed thoroughly paper. findings underscore urgent need collaborative efforts among policym... Read More

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