Lithium iron phosphate battery
A lithium iron phosphate battery (LiFePO₄ battery or LFP battery) is a rechargeable lithium-ion battery that employs lithium iron phosphate (LiFePO₄) as the cathode material paired with a graphitic carbon anode, delivering a nominal cell voltage of 3.2 volts.[1][2] This chemistry leverages the stable olivine crystal structure of the cathode to provide inherent thermal and chemical stability, substantially reducing the risk of thermal runaway, fire, or explosion even under abuse conditions like overcharge or short-circuit, unlike cobalt-based lithium-ion variants.[1][2] Invented in 1996 by John B. Goodenough and Arumugam Manthiram at the University of Texas at Austin, LiFePO₄ batteries entered commercialization in the early 2000s, initially dominated by Chinese manufacturers who scaled production for cost advantages amid abundant iron and phosphate resources.[3][4] They exhibit energy densities of 90-160 Wh/kg and support over 2,000-5,000 charge-discharge cycles with minimal capacity fade, alongside low self-discharge rates and operational tolerance up to 60°C, making them suitable for demanding environments.[5][6] However, their lower volumetric and gravimetric energy density compared to nickel-manganese-cobalt (NMC) batteries results in larger, heavier packs for equivalent capacity, and they underperform in cold temperatures below 0°C due to sluggish lithium-ion diffusion.[6][5] LiFePO₄ batteries have achieved widespread adoption in electric vehicles for their safety profile and cobalt-free composition, which mitigates supply chain vulnerabilities and ethical mining issues, as well as in stationary battery energy storage systems (BESS) where longevity outweighs peak power needs.[4][7] Ongoing advancements, including cathode doping and solid-state electrolytes, aim to boost energy density while preserving core safety attributes, positioning LFP as a cornerstone for scalable electrification and grid resilience.[3]Chemistry and Materials
Cathode Structure and Composition
The cathode active material in lithium iron phosphate (LiFePO₄) batteries is primarily composed of stoichiometric LiFePO₄, a polyanionic compound featuring lithium, iron, phosphorus, and oxygen in a 1:1:1:4 ratio.[8] This material is typically synthesized via solid-state reactions, hydrothermal methods, or sol-gel processes using precursors such as iron salts, lithium sources, and phosphoric acid, followed by high-temperature annealing around 600–900°C to achieve phase purity.[9] In practical implementations, the LiFePO₄ particles are often coated with a thin carbon layer (1–5 wt%) to mitigate intrinsic low electronic conductivity (approximately 10⁻⁹ S/cm), enhancing charge transfer without altering the core composition.[10] LiFePO₄ crystallizes in an olivine-type structure, orthorhombic with space group Pnma (No. 62), forming a three-dimensional framework of edge- and corner-sharing polyhedra.[11] Lithium ions reside in octahedral sites (LiO₆), iron(III) occupies distorted octahedral sites (FeO₆), and PO₄ groups form rigid tetrahedral units that stabilize the lattice and contribute to thermal stability.[12] This arrangement creates one-dimensional channels along the b-axis for lithium ion migration, with a theoretical capacity of 170 mAh/g derived from the Fe²⁺/Fe³⁺ redox couple at around 3.4 V vs. Li/Li⁺. Lattice parameters are typically a ≈ 10.33 Å, b ≈ 6.01 Å, and c ≈ 4.69 Å, with minor variations depending on synthesis conditions and doping.[8][13] Doping with supervalently substituted ions (e.g., Mg²⁺ or Al³⁺ at 0.5–2 mol%) or partial manganese substitution (forming LiMnₓFe₁₋ₓPO₄) can refine the composition to improve ionic conductivity or voltage plateau, but pure LiFePO₄ remains the baseline for its structural integrity and safety, as the strong P–O bonds prevent oxygen release even at elevated temperatures up to 270°C.[14][15] These modifications must preserve the olivine phase to avoid capacity loss from phase impurities like Fe₂P or Li₃PO₄.[16]Anode, Electrolyte, and Cell Design
The anode in lithium iron phosphate (LiFePO4) batteries is typically composed of graphite, a graphitic carbon material that serves as the negative electrode by intercalating lithium ions during charging.[17][18] This graphite layer is coated onto a copper foil current collector, which provides electrical conductivity and structural support, enabling reversible lithium insertion and extraction with minimal volume expansion compared to alternative materials like silicon.[18] The choice of graphite stems from its established electrochemical stability and capacity of approximately 372 mAh/g, contributing to the battery's overall cycle life exceeding 2000 cycles in many designs.[19] The electrolyte is a non-aqueous liquid formulation that facilitates lithium-ion transport between the anode and cathode while preventing electron conduction. It commonly consists of lithium hexafluorophosphate (LiPF6) as the salt dissolved in a mixture of organic carbonate solvents, such as ethylene carbonate (EC) and dimethyl carbonate (DMC), at concentrations around 1 M.[20] This composition ensures ionic conductivity of 5–10 mS/cm at room temperature and operates effectively within the LiFePO4 voltage window of 2.0–3.6 V, though it can decompose at elevated temperatures above 60°C, prompting research into more stable alternatives like ether-based electrolytes for enhanced safety.[21] Additives, such as vinylene carbonate, are often incorporated to form a solid electrolyte interphase (SEI) layer on the anode, reducing irreversible capacity loss during initial cycles.[20] Cell design integrates the anode, cathode, and electrolyte within a sealed enclosure, typically employing either stacked flat electrodes or wound jelly-roll configurations to maximize active material utilization. A porous polyolefin separator, usually polyethylene (PE) or polypropylene (PP) microporous film with thicknesses of 10–25 μm, prevents direct contact between electrodes while allowing electrolyte permeation and ion diffusion; its pore size (around 0.1 μm) balances shutdown functionality for overheat protection with low ionic resistance.[22] The anode (graphite on copper) and cathode (LiFePO4 on aluminum foil) are alternated with separators, impregnated with electrolyte, and housed in formats like prismatic cells for high-capacity applications (e.g., 700 Ah modules in energy storage) or cylindrical/pouch for compactness.[19] Prismatic designs, such as those in BYD's Blade battery, prioritize thermal management and scalability, achieving volumetric energy densities up to 419 Wh/L at the cell level as of 2024.[19]History
Invention and Early Development
The lithium iron phosphate (LiFePO4) cathode material for rechargeable lithium batteries was discovered in 1996 by a research team led by John B. Goodenough at the University of Texas at Austin. Akshaya K. Padhi, a doctoral student in the group, synthesized the olivine-structured compound and demonstrated its electrochemical activity, achieving an initial specific capacity of approximately 130 mAh/g at a discharge voltage plateau of 3.4 V versus metallic lithium. This breakthrough identified LiFePO4 as part of a broader class of polyanion phosphates with enhanced stability due to the robust P-O covalent bonds, which suppress phase transitions and thermal decomposition risks inherent in layered oxide cathodes like LiCoO2. The foundational work built on Goodenough's prior exploration of lithium-ion intercalation in solid-state materials, extending from his 1980 invention of the LiCoO2 cathode. Early characterization revealed LiFePO4's theoretical gravimetric capacity of 170 mAh/g, limited in practice by the material's intrinsically low electronic conductivity (around 10-9 S/cm) and sluggish lithium diffusion kinetics. Initial prototypes used carbon black additives to improve conductivity, but rate performance remained suboptimal, prompting subsequent refinements. A key U.S. patent application for these phosphate-based cathodes, listing Goodenough, Padhi, and colleagues as inventors, was filed on April 5, 1996, laying the groundwork for further development despite challenges in scaling synthesis for uniform particle morphology and nanosizing. By 1997, the team's publications in the Journal of the Electrochemical Society detailed the reversible Fe2+/Fe3+ redox couple at the olivine framework's active sites, confirming two-phase insertion/extraction behavior without significant structural degradation over initial cycles.[23] These findings highlighted LiFePO4's potential for safer, longer-life batteries, though electronic limitations delayed immediate commercialization until conductivity enhancements like carbon coating were introduced in the early 2000s. Early efforts focused on optimizing olivine-phase purity via high-temperature solid-state reactions, achieving up to 90% of theoretical capacity in lab cells under ambient conditions.Commercialization and Key Milestones
Commercialization of lithium iron phosphate (LiFePO4) batteries accelerated in the mid-2000s after advancements in nanoscale cathode materials overcame early electronic conductivity limitations, enabling viable high-rate performance for portable and transportation applications. A123 Systems, founded in 2001 as a Massachusetts Institute of Technology spin-out, pioneered scalable production of Nanophosphate LiFePO4 cells, targeting markets where safety and power density outweighed lower energy density compared to cobalt-based alternatives.[24] The company's technology emphasized olivine-structured cathodes coated for improved ion diffusion, facilitating initial adoption in demanding sectors like power tools and hybrid vehicles.[25] A pivotal milestone occurred in early 2006 when A123 Systems launched its first commercial products, consisting of cylindrical LiFePO4 cells for portable power applications such as cordless tools from Black & Decker, achieving discharge rates up to 30C while maintaining thermal stability.[25] Expansion into automotive markets followed in 2007, with A123 supplying battery packs for demonstration fleets and prototypes, including a partnership with General Motors for the Chevrolet Volt's initial hybrid system testing, where LiFePO4's abuse tolerance reduced fire risks in crash scenarios. By 2009, A123 operationalized a 12 MW manufacturing facility in Michigan, marking the first large-scale U.S. production of automotive-grade LiFePO4 batteries and supporting deployments in electric motorcycles and buses.[26] In parallel, Valence Technology commercialized phosphate-based modules during this period, focusing on prismatic cells for stationary storage and plug-in hybrids, with early shipments enabling aftermarket conversions of Toyota Prius vehicles by 2008, demonstrating over 2,000 cycles at 80% depth of discharge.[27] Chinese firms, including BYD, entered mass production around 2008, integrating LiFePO4 packs into the F3DM plug-in hybrid sedan, which featured a 16 kWh battery enabling 60 km electric range, though initial volumes were limited by higher costs relative to nickel-manganese-cobalt chemistries.[28] Subsequent milestones included patent expirations starting in the early 2010s, which reduced licensing barriers and spurred global scaling; for instance, Hydro-Québec's foundational LiFePO4 patents lapsed around 2011, facilitating broader adoption. By the mid-2010s, Chinese manufacturers like BYD and CATL achieved gigawatt-hour-scale output, driving cost declines to under $100/kWh by 2020 through optimized supply chains for iron and phosphate precursors. A123's challenges culminated in its 2012 bankruptcy amid aggressive expansion and recalls, leading to acquisition by China's Wanxiang Group, which revitalized operations for industrial applications.[24] Recent growth reflects EV sector shifts, with Tesla incorporating LFP cells from CATL in Model 3 and Y vehicles from 2021, capturing over 30% of the global EV battery market share for this chemistry by 2022 due to its longevity exceeding 3,000 cycles in fleet use.[28]Electrochemical Performance
Voltage Profile and Capacity
The lithium iron phosphate (LiFePO4) cathode delivers a nominal operating voltage of 3.2 V per cell, with a full charge cutoff at 3.65 V and discharge cutoff at 2.5 V to prevent over-discharge damage.[29][30] The discharge voltage profile features a pronounced flat plateau at approximately 3.3–3.4 V, which spans the majority of the capacity range, typically from near full charge to around 20% state of charge (SOC).[31][32] This stability contrasts with sloping curves in other lithium-ion chemistries and enables consistent power delivery, though it complicates precise SOC estimation via voltage alone due to minimal variation in the mid-range.[33] The theoretical specific capacity of the LiFePO4 cathode material is 170 mAh/g, derived from the one-electron Fe^{2+}/Fe^{3+} redox reaction and the formula unit's lithium content.[34][35] Commercial implementations achieve practical gravimetric capacities of 150–160 mAh/g at low C-rates (e.g., 0.1C), with values occasionally reaching 120–140 mAh/g under higher discharge rates due to kinetic limitations.[36][34] At the full cell level, this translates to energy densities of approximately 120–160 Wh/kg, depending on anode pairing (typically graphite), electrolyte, and packaging efficiency.[37] Capacity retention remains high, with initial coulombic efficiencies exceeding 95% in optimized carbon-coated variants.[38]Charge-Discharge Kinetics
The charge-discharge process in lithium iron phosphate (LiFePO₄) batteries proceeds via a two-phase electrochemical reaction in the olivine cathode, where Li⁺ ions and electrons are inserted into FePO₄ during discharge to form LiFePO₄ (with Fe³⁺ reduced to Fe²⁺), and the reverse deintercalation occurs during charging. This biphasic mechanism yields a characteristic flat voltage plateau at ~3.4 V vs. Li/Li⁺, driven by the thermodynamic stability of the end-member phases, and involves a ~6.8% lattice volume expansion from FePO₄ to LiFePO₄.[39][40] Kinetics are primarily limited by anisotropic Li⁺ solid-state diffusion within the crystal channels (fastest along the b-axis at ~10^{-12} to 10^{-10} cm²/s chemical diffusion coefficient) and low intrinsic electronic conductivity (~10^{-9} S/cm), resulting in polarization at high rates and incomplete phase conversion if particles exceed micron sizes. The phase boundary propagates via a shrinking-core model, where delithiation starts at particle surfaces, but sluggish interfacial kinetics and ~7% strain can induce microcracks or incomplete utilization at C-rates >1C without mitigation. At low overpotentials or high rates, a non-equilibrium solid-solution path may emerge, enabling partial Li occupancy in a mixed-phase regime, though this increases overpotential and reduces efficiency.[41][42][43] Enhancements such as carbon coating (boosting conductivity to 10^{-2}–10^{0} S/cm), nanosizing (reducing diffusion lengths to <100 nm), and doping (e.g., with supervalent ions to widen channels) improve rate capability, allowing >80% capacity retention at 5–10C discharge in optimized cells. Charge protocols typically employ constant current-constant voltage (CCCV) up to 3.65 V, with kinetics favoring slower rates (0.5–1C) to minimize Li plating or SEI growth on the graphite anode, though fast-charging variants target 3–6C via electrolyte optimization. Electrolyte properties, including ionic conductivity and desolvation energy, further modulate interfacial kinetics, as demonstrated in model systems where they dominate porous electrode performance.[44][45][46]Key Performance Characteristics
Energy and Power Density
Lithium iron phosphate (LiFePO4) batteries typically achieve gravimetric energy densities of 90-160 Wh/kg at the cell level, which is lower than that of nickel-manganese-cobalt (NMC) batteries exceeding 200 Wh/kg.[47][48] Volumetric energy densities range from 140-330 Wh/L, influenced by cell design and packaging efficiency.[49] These values stem from the cathode's theoretical specific capacity of about 170 mAh/g and an average discharge voltage of 3.2-3.3 V, resulting in a theoretical energy density of approximately 580 Wh/kg for the active material alone, though practical cells realize only 15-25% of this due to inactive components like current collectors, separators, and electrolytes.[49] The lower energy density compared to higher-voltage chemistries arises from the stable olivine crystal structure of LiFePO4, which limits ion diffusion paths and voltage plateau but prioritizes structural integrity over energy maximization.[50] Recent advancements, such as large-particle LiFePO4 cathodes produced via mechanofusion, have demonstrated up to 28% improvements in practical energy density through reduced surface area and enhanced packing, achieving closer to 170 Wh/kg in prototype cells.[50] In contrast, LiFePO4 batteries excel in power density, often surpassing NMC in sustained high-rate discharge capability due to low internal resistance and rapid lithium-ion diffusion kinetics enabled by the cathode's one-dimensional channels.[51] Commercial cells support continuous discharge rates of 1-3C (3.2-10 kW/kg equivalent at nominal voltage) and peak rates up to 10-50C in specialized designs, facilitating applications requiring bursts of power without significant voltage sag or heat buildup.[52] This high power-to-energy ratio positions LiFePO4 as preferable for high-power demands like electric vehicle acceleration or grid frequency regulation, despite the energy trade-off.[53]Cycle Life and Degradation Mechanisms
Lithium iron phosphate (LFP) batteries demonstrate exceptional cycle life compared to other lithium-ion chemistries, often achieving 2000 to 5000 full charge-discharge cycles at 100% depth of discharge (DoD) while retaining 80% of nominal capacity (typically 150-170 mAh/g) under controlled conditions of 25°C and 1C rate.[51] [54] At shallower DoD levels, such as 80%, cycle life can extend to 4500-8000 cycles, with further gains at 50% DoD exceeding 10,000 cycles due to reduced mechanical and chemical stress on electrodes.[51] These values stem from the structural stability of the olivine-phase LiFePO4 cathode, which experiences negligible volume change (<1%) during lithium intercalation, minimizing particle cracking and active material loss.[55] Degradation in LFP batteries primarily manifests as gradual capacity fade rather than abrupt failure, with key mechanisms including loss of lithium inventory (LLI) via solid electrolyte interphase (SEI) growth on the graphite anode and, to a lesser extent, loss of active material (LAM) in both electrodes.[56] [57] SEI formation consumes cyclable lithium through electrolyte reduction, particularly during initial cycles and accelerated by high temperatures or overcharge, leading to impedance rise and reduced Coulombic efficiency.[58] In calendar aging scenarios—storage without cycling—degradation intensifies at elevated state-of-charge (SOC >90%) and temperatures above 40°C, driven by parasitic reactions such as cathode-electrolyte interface evolution and minor Fe^{3+} dissolution, though the latter is mitigated by LFP's low operating voltage plateau (3.2-3.3 V).[59] [60] Cycling-induced degradation varies with operational parameters: at low temperatures (<0°C), lithium plating on the anode can occur, exacerbating LLI and posing safety risks, while high-rate cycling (>2C) promotes LAM through particle pulverization in the anode despite cathode robustness.[55] Elevated temperatures shift mechanisms toward accelerated SEI growth and electrolyte decomposition, with studies showing capacity retention dropping to 80% after 3000 cycles at 55°C versus near-100% at 25°C.[61] Unlike nickel-based cathodes, LFP's phosphate framework resists oxygen release and phase transitions, contributing to <0.02% capacity fade per cycle under optimal conditions, though real-world applications like electric vehicles may see accelerated aging from combined cycling and calendar effects.[55][60]Temperature Sensitivity
Lithium iron phosphate (LFP) batteries exhibit a broad operating temperature range for discharge, typically from -20°C to 60°C, though optimal performance occurs between 20°C and 40°C.[62] [63] Charging is generally restricted to 0°C to 55°C to prevent lithium plating on the anode, which can cause irreversible capacity loss and safety risks.[64] Outside these ranges, electrochemical kinetics slow, ionic conductivity decreases, and internal resistance rises, impacting capacity, power output, and cycle life.[65] At low temperatures below 0°C, LFP batteries experience significant capacity fade due to reduced lithium-ion diffusion in the olivine-structured cathode and sluggish electrolyte dynamics, leading to voltage slump under load and diminished discharge efficiency.[65] [66] For instance, discharge capacity can drop substantially as temperatures approach -20°C, with studies showing viability for operation but at reduced usable energy compared to room temperature.[67] Charging in sub-zero conditions exacerbates issues, as lithium plating forms metallic dendrites, permanently reducing capacity and potentially short-circuiting cells.[68] Despite these limitations, LFP retains more capacity in cold conditions than lead-acid alternatives, attributed to its stable phosphate framework.[69] Elevated temperatures above 45°C accelerate degradation mechanisms, including solid electrolyte interphase (SEI) growth on the graphite anode and cathode particle cracking from thermal stress, resulting in faster capacity fade during cycling.[70] [71] Commercial prismatic LFP/graphite cells cycled at 45°C retain only 90% capacity after fewer than 500 cycles, compared to thousands at ambient conditions.[71] However, LFP's inherent thermal stability mitigates risks like oxygen release or exothermic decomposition, with thermal runaway onset exceeding 200°C—far higher than other lithium-ion chemistries.[72] [73] High-temperature exposure also increases self-discharge and electrolyte side reactions, shortening overall lifespan unless mitigated by advanced electrolytes or coatings.[74]Safety Profile
Thermal Runaway Resistance
Lithium iron phosphate (LFP) batteries demonstrate superior resistance to thermal runaway compared to other lithium-ion chemistries due to their stable olivine crystal structure and strong P-O bonds in the phosphate framework, which require higher temperatures for decomposition and oxygen release.[75] Thermal runaway in lithium-ion batteries involves exothermic reactions leading to uncontrolled temperature rise, often triggered by abuse conditions like overcharge or internal shorts, but LFP cells typically onset self-heating at around 150–210°C, with maximum temperatures during runaway reaching approximately 250°C, significantly lower than the 600–900°C observed in nickel-manganese-cobalt (NMC) cells.[76] [77] This resistance stems from the cathode's thermal stability; the LiFePO4 material decomposes at temperatures exceeding 270°C without readily liberating oxygen to fuel combustion, unlike oxide-based cathodes where weaker metal-oxygen bonds facilitate rapid propagation.[78] Experimental overcharge tests on prismatic LFP cells show that while voltage drops and gas venting occur, the process rarely escalates to sustained fire or explosion, with heat generation insufficient for self-propagation to adjacent cells.[79] In accelerating rate calorimetry studies, LFP batteries under mechanical abuse exhibit controlled failure modes, with critical runaway temperatures around 346°C in some configurations, emphasizing their lower hazard profile for applications like electric vehicles.[80] Comparative abuse testing confirms LFP's advantages: NMC batteries initiate thermal runaway at lower thresholds (often below 200°C) and release more energy, increasing fire risk, whereas LFP's phosphate chemistry limits exothermic output and suppresses flame propagation, as evidenced by non-combustible behavior even under puncture or overheating.[81] However, LFP is not immune; factors like state-of-charge above 50% can lower onset temperatures, and large-format cells may generate pressures during venting, necessitating robust enclosure designs to mitigate explosion risks in confined spaces.[82] Peer-reviewed analyses attribute this inherent safety to causal factors in the material's bonding energy, rather than additives alone, underscoring LFP's suitability for high-safety demands despite ongoing research into edge-case failures.[83]Abuse Testing and Failure Analysis
Abuse testing of lithium iron phosphate (LFP) batteries evaluates resilience to mechanical, electrical, and thermal stresses through standardized protocols such as nail penetration, crush, overcharge, external short circuit, and accelerated rate calorimetry. These tests simulate real-world failure scenarios like collisions or misuse, assessing metrics including temperature rise, voltage drop, gas emissions, and propagation to fire or explosion. LFP batteries generally demonstrate superior safety margins due to the stable olivine structure of the cathode, which resists oxygen release during decomposition, unlike layered oxide cathodes.[84][76] In mechanical abuse tests, such as crush or punch deformation, LFP cells undergo distinct stages: initial elastic-plastic deformation (Stage I), internal short circuit initiation (Stage II) marked by rapid voltage drop exceeding 10 mV/s and white smoke emission, escalation to thermal runaway (Stage III) with casing rupture, and subsequent cooling (Stage IV). For 32 Ah prismatic LFP cells deformed up to 84% surface area using spherical, flat, or conical punches, critical forces ranged from 3 kN (conical) to 190 kN (flat), with displacements of 3.59–8.63 mm; mechanical response showed independence from state of charge (SOC), but higher SOC amplified thermal severity via increased energy release. Nail penetration tests on LFP cells at 100% SOC revealed minimal hazard, with no fire or explosion observed despite internal short circuits and temperature rises scaling with nail diameter (2–8 mm); hazard severity ranked lowest among common chemistries (LCO > NMC > LMO > LFP), attributed to milder short-circuit currents and suppressed electrolyte ejection.[78][85] Electrical abuse, including overcharge and short circuit, induces lithium plating and electrolyte breakdown in LFP cells, but outcomes are less catastrophic than in alternatives; overcharge activates current interrupt devices with voltage spikes, often without fire propagation, though aged cells may tolerate higher overcharge before safeguards engage. Failure analysis via computed tomography post-squeezing reveals deformation-induced separator breaches leading to localized shorts, with electrolyte decomposition contributing to gas buildup but limited venting severity due to the cathode's thermal stability.[86][87] Thermal abuse tests, such as oven heating or adiabatic conditions, trigger self-heating onset at 136–151°C (decreasing slightly with SOC above 25%), with full thermal runaway at 220–230°C; maximum temperatures reached 306–620°C, escalating with SOC (e.g., 953°C/min rise rate at 100% SOC vs. negligible at 25%), involving sequential reactions: solid electrolyte interphase decomposition, anode-electrolyte interactions, valve opening, and massive shorts. No severe runaway occurs below 50% SOC, and while venting and smoke occur, ignition is rare, enabling safety boundaries modeled as functions of deformation factors for risk prediction. Overall failure analysis underscores internal shorts as primary causal initiators across abuses, with LFP's lower exothermic cathode reactions mitigating propagation compared to oxygen-evolving alternatives.[76][78]Comparisons with Alternative Chemistries
Versus Nickel-Manganese-Cobalt (NMC)
Lithium iron phosphate (LFP) batteries exhibit lower gravimetric energy density, typically ranging from 90 to 160 Wh/kg, compared to nickel-manganese-cobalt (NMC) batteries, which achieve 150 to 250 Wh/kg depending on the nickel content, necessitating larger and heavier packs for equivalent energy storage in applications like electric vehicles.[88][89] NMC's higher density stems from its cathode structure incorporating nickel for greater capacity, though this comes at the expense of reduced thermal stability.[90] In terms of safety, LFP demonstrates superior resistance to thermal runaway, with onset temperatures around 230°C versus 160°C for NMC cells, resulting in lower gas production and reduced fire risk during abuse conditions such as overcharge or puncture.[91][92] Peer-reviewed analyses confirm NMC's greater propensity for structural degradation and exothermic reactions due to oxygen release from the cathode, whereas LFP's phosphate-based framework provides an inherent thermal buffer.[93][90] Cycle life favors LFP, often exceeding 2000 full charge-discharge cycles with minimal capacity fade, outperforming NMC's typical 1000 to 1500 cycles under similar conditions, primarily because LFP experiences less lithium loss and cathode dissolution.[90][94] Degradation in NMC accelerates via nickel dissolution and electrolyte decomposition, particularly at high states of charge, while LFP's olivine structure mitigates these effects.[95]| Parameter | LFP | NMC |
|---|---|---|
| Nominal Voltage | 3.2 V | 3.6–3.7 V |
| Energy Density (Wh/kg) | 90–160 | 150–250 |
| Cycle Life (cycles) | >2000 | 1000–1500 |
| Thermal Runaway Temp (°C) | ~230 | ~160 |
| Relative Cost | Lower (30% less) | Higher |
Versus Lithium Cobalt Oxide (LCO)
Lithium iron phosphate (LFP) batteries possess lower gravimetric energy density than lithium cobalt oxide (LCO) batteries, typically ranging from 90–160 Wh/kg for LFP compared to 150–200 Wh/kg for LCO, limiting LFP's suitability for space-constrained applications like portable electronics where LCO excels due to its higher capacity per unit mass.[97] [98] Volumetric energy density follows a similar trend, with LCO achieving approximately 250–400 Wh/L versus LFP's 220–300 Wh/L, though LFP compensates with higher power density in some high-rate discharge scenarios owing to its structural stability.[97] [99]| Parameter | LFP (LiFePO₄) | LCO (LiCoO₂) |
|---|---|---|
| Nominal Voltage (V) | 3.2 | 3.7 |
| Cycle Life (cycles) | 2,000–5,000 | 500–1,000 |
| Thermal Runaway Temp (°C) | >270 | 150–200 |
| Cost (relative) | Lower (no cobalt) | Higher (cobalt-dependent) |
Versus Lead-Acid and Other Types
Lithium iron phosphate (LiFePO4) batteries exhibit significantly higher gravimetric energy density than lead-acid batteries, typically ranging from 90 to 160 Wh/kg compared to 30 to 50 Wh/kg for lead-acid types such as flooded or absorbed glass mat (AGM) variants.[105][106] This disparity enables LiFePO4 batteries to store more energy per unit mass, resulting in lighter systems for equivalent capacity, which is advantageous for applications like electric vehicles and portable power where weight reduction improves efficiency.[107] In contrast, lead-acid batteries' lower density stems from their heavier lead electrodes and electrolyte, limiting their suitability for weight-sensitive uses despite their tolerance for high discharge currents.[108] Cycle life further favors LiFePO4, with capacities often exceeding 2,000 to 5,000 full charge-discharge cycles at 80% depth of discharge (DoD) before reaching 80% capacity retention, versus 300 to 1,000 cycles for lead-acid under similar conditions.[109][110] This longevity arises from LiFePO4's stable olivine crystal structure, which resists degradation mechanisms like electrode dissolution prevalent in lead-acid batteries, where sulfation and grid corrosion accelerate failure during deep discharges.[111] Consequently, LiFePO4 systems demonstrate lower lifecycle costs, estimated at 2.8 times cheaper per usable kWh over time despite 2-3 times higher upfront pricing (approximately $150-300/kWh for LiFePO4 packs versus $50-100/kWh for lead-acid).[106][112] Safety profiles differ markedly: LiFePO4 batteries maintain structural integrity under abuse, with thermal runaway temperatures exceeding 270°C due to strong P-O bonds, reducing risks of fire or explosion compared to lead-acid's potential for acid spills, hydrogen gassing, and venting during overcharge.[113] Lead-acid batteries, while recyclable at rates over 95% in developed regions, pose environmental hazards from lead contamination if improperly handled, whereas LiFePO4 avoids toxic electrolyte leaks but requires careful management of lithium components at end-of-life.[114] Charging efficiency is also superior in LiFePO4 (90-95%), enabling faster recharge rates without excessive heat, unlike lead-acid's 70-85% efficiency and need for equalization charges to prevent imbalance.[111]| Parameter | LiFePO4 | Lead-Acid |
|---|---|---|
| Gravimetric Energy Density (Wh/kg) | 90-160[105] | 30-50[106] |
| Cycle Life (to 80% retention) | 2,000-5,000 cycles[109] | 300-1,000 cycles[110] |
| Initial Cost (per kWh) | $150-300[106] | $50-100[106] |
| Charging Efficiency | 90-95%[111] | 70-85%[111] |
| Maintenance | None required[113] | Periodic watering, equalization[108] |
Economic and Supply Factors
Cost Structure and Scalability
The cost structure of lithium iron phosphate (LFP) batteries is characterized by lower material expenses compared to nickel-manganese-cobalt (NMC) chemistries, primarily due to the use of abundant iron and phosphate in the cathode, which avoids costly and scarce cobalt and nickel. Bill of materials typically accounts for around 50% of total battery costs, with LFP cathode reagents being approximately $15/kWh cheaper than NMC equivalents, supplemented by $5/kWh lower manufacturing overheads from simpler synthesis processes.[118][119] Anode and electrolyte components remain similar across lithium-ion variants, but LFP's overall pack-level costs for plug-in hybrid electric vehicles were estimated at $145–200/kWh in model year 2023, reflecting economies in cathode production.[120] Pack prices for LFP batteries have declined rapidly amid scaling production, reaching averages of $98.5/kWh in recent analyses, with Chinese cell prices dropping to around $44–70/kWh by 2024–2025 due to oversupply and process optimizations.[121][122] Overall lithium-ion pack prices, inclusive of LFP, fell 20% year-over-year to $115/kWh in 2024, with volume-weighted estimates averaging $103/kWh across NMC and LFP for 2025, driven by LFP's 19% cost edge over NMC in reference comparisons adjusted for localization.[123][124][122] Scalability benefits from LFP's reliance on globally abundant raw materials—iron from steel industry byproducts and phosphate from fertilizer mining—enabling rapid capacity expansion without the supply bottlenecks plaguing cobalt-dependent cells.[96] Manufacturing processes are simpler and more adaptable, requiring minimal retooling for existing lithium-ion lines, which has allowed dominant producers in China to achieve consistent quality at gigafactory scales since 2020.[125][126] Projections indicate further cost reductions of 17–27% by model year 2035 through yield improvements and vertical integration, positioning LFP for widespread adoption in mass-market applications despite lower energy density.[120]Resource Availability
Lithium iron phosphate (LFP) batteries derive their cathode materials from lithium, iron, and phosphate, which are sourced from lithium salts like lithium carbonate or hydroxide, iron ore, and phosphate rock. These inputs are more plentiful and less geostrategically constrained than the cobalt and nickel prevalent in alternative lithium-ion chemistries such as NMC, reducing vulnerability to supply disruptions from concentrated mining regions like the Democratic Republic of Congo for cobalt.[127][128] Iron, the core metallic component, faces no meaningful scarcity risks, with global resources exceeding 800 billion tons of crude ore containing more than 230 billion tons of recoverable iron; production is dominated by Australia and Brazil, which together account for over half of annual output, ensuring stable availability for battery-scale applications without classification as a critical raw material.[129] Phosphate rock, providing the phosphorus and oxygen framework, boasts world resources over 300 billion tons, supporting current global mining rates of approximately 220 million tons annually with no projected shortages in the near term; however, only select high-purity deposits are viable for battery-grade ferric phosphate synthesis, and surging LFP adoption—projected to drive phosphorus demand from batteries to rival fertilizer uses—could elevate pressures on refining capacity, particularly as China controls 45% of mined supply and Morocco holds about 70% of reserves.[130][131][132] Lithium remains the most constrained element for LFP scaling, with global resources estimated at 115 million tons and reserves around 26 million tons as of 2025, amid battery demand consuming 87% of output; while LFP avoids cobalt and nickel, its cathode's lower energy density (typically 120-160 Wh/kg versus 200-250 Wh/kg for NMC) requires roughly 20-30% more active material mass per kWh, implying comparable or slightly higher lithium intensity per energy unit, though overall system costs benefit from cheaper non-lithium inputs and expanding supply from brine and hard-rock projects in Australia, Chile, and emerging U.S. sources like Arkansas brines potentially holding 5-19 million tons.[133][134][135]Global Supply Chain Vulnerabilities
The global supply chain for lithium iron phosphate (LFP) batteries exhibits high concentration, with China controlling over 98% of LFP cathode production and approximately 94% of overall LFP battery manufacturing as of 2024.[136][137] This dominance extends to upstream processing, including 70% of global refined lithium and the majority of battery-grade materials integration, amplifying risks from single-point failures in a single geopolitical actor.[137][138] In contrast to nickel-manganese-cobalt (NMC) chemistries, LFP avoids cobalt and nickel bottlenecks but remains vulnerable due to 92% of its cathodes originating from China, heightening exposure to trade disruptions compared to NMC's 80% concentration.[139] Geopolitical tensions exacerbate these issues, as evidenced by China's 2025 export controls on lithium-ion battery technologies and rare earth elements, which have materialized long-standing concentration risks and disrupted global flows.[140] Incidents such as CATL's mining suspensions in August 2025 further highlight operational fragilities, underscoring Europe's and the US's dependence on Chinese supply for LFP scaling.[141] Lithium supply risks persist despite LFP's lower per-kWh lithium intensity relative to some alternatives; global deficits were projected for 2022-2023, with ongoing concentration in processing leaving downstream markets susceptible to price volatility and shortages.[142][143] Phosphate refining poses an emerging bottleneck, as LFP demands high-purity phosphoric acid (PPA) derived from phosphate rock, with production scaling strained by limited battery-grade facilities outside China and potential demand surges tied to LFP's rising market share—now nearly 50% of global electric vehicle batteries in 2024.[138][132] Iron sourcing, however, faces minimal vulnerabilities due to its abundance and diffuse global supply, mitigating one material risk inherent to LFP's composition.[138] Efforts to diversify, such as US incentives under the Inflation Reduction Act targeting non-Chinese materials by 2027, have yet to substantially erode these dependencies, leaving supply chains exposed to policy shifts and regional overcapacity in China exceeding 2 TWh annually against lower demand.[137][144]Applications
Electric Vehicles
Lithium iron phosphate (LFP) batteries have seen widespread adoption in electric vehicles (EVs) primarily due to their cost advantages and improved safety characteristics relative to nickel-manganese-cobalt (NMC) chemistries.[96][145] In 2024, LFP batteries comprised nearly half of the global EV battery market by capacity, driven largely by demand in China where their share exceeded 50% for electric car batteries and reached 64% in the fourth quarter.[131][146] Manufacturers such as BYD have integrated LFP cells exclusively across their passenger EV lineup, including the Blade battery design, which emphasizes structural integration for enhanced pack efficiency.[96][147] Tesla began incorporating LFP batteries, sourced from suppliers like CATL and BYD, in its Model 3 and Model Y standard-range variants starting in 2021, enabling price reductions and full 100% state-of-charge recommendations without the degradation risks associated with higher-nickel cathodes.[148][149] The appeal of LFP in EVs stems from its superior thermal stability, which minimizes risks of thermal runaway and fire incidents compared to NMC batteries, alongside a cycle life often surpassing 2,000 full charge-discharge equivalents under typical operating conditions.[90][148] This longevity supports extended warranties, with some LFP-equipped EVs projected to retain over 70% capacity after 10 years or 200,000 miles of use, reducing long-term ownership costs for high-mileage applications like ride-sharing fleets.[90][150] Cost structures benefit from LFP's avoidance of scarce cobalt and nickel, yielding packs approximately 30% cheaper per kilowatt-hour than equivalent NMC systems as of 2024.[90][96] These factors have facilitated EV market expansion in price-sensitive segments, contributing to LFP's dominance in China's EV sales, where it held about 75% share in some analyses for 2024.[151] However, LFP's lower gravimetric energy density—typically 160-180 Wh/kg versus 200-250 Wh/kg for NMC—necessitates larger or heavier packs to achieve comparable range, potentially limiting appeal in premium or long-range EVs.[152][153] For instance, LFP-equipped Tesla Model 3 variants offer around 272 miles of EPA-rated range, compared to over 300 miles for NMC versions with similar pack sizes.[148] Charging speeds can also lag due to this density constraint, though advancements in cell design have narrowed the gap.[154] Despite these trade-offs, LFP's safety and cost profile has prompted diversification beyond China, with Western OEMs like Ford adopting it for models such as the Mustang Mach-E to balance affordability and reliability.[96] Ongoing innovations, including higher-density LFP variants, aim to mitigate range limitations while preserving core advantages.[145]Stationary Energy Storage
Lithium iron phosphate (LFP) batteries are increasingly adopted in stationary energy storage systems (ESS) for applications such as grid frequency regulation, renewable energy integration, and load shifting, owing to their superior thermal stability that reduces the risk of thermal runaway compared to nickel-based chemistries, enabling safer operation in large-scale installations without extensive cooling requirements.[155] Their olivine crystal structure provides inherent resistance to overcharge and high temperatures, with decomposition occurring only above 270°C, far exceeding the stability limits of alternatives like nickel-manganese-cobalt (NMC).[90] Additionally, LFP's absence of scarce or ethically contentious materials like cobalt lowers costs, with LFP modules priced approximately 10% below equivalent NMC systems as of 2022, facilitating scalability for utility-grade deployments.[156] Prominent examples include Tesla's Megapack units, which transitioned to LFP chemistry in 2021 for enhanced cost-efficiency and cycle durability in grid storage, with each containerized system capable of storing 3.9 MWh while supporting durations of 2-4 hours at multi-megawatt power levels.[157][158] Deployments of such systems have proliferated globally, contributing to the 53% year-over-year increase in battery energy storage system (BESS) installations reaching 205 GWh in 2024, where LFP's dominance in stationary segments stems from its alignment with frequent shallow-discharge cycles typical of grid services.[159] Smaller-scale implementations, such as Engie Energy Access's hybrid solar mini-grid in Uganda's Lolwe Islands, demonstrate LFP's viability in off-grid stationary roles, pairing photovoltaic generation with LFP storage for reliable power delivery.[160] Performance metrics underscore LFP's suitability, with cycle lives ranging from 4,000 to 15,000 full equivalents before capacity retention falls below 80%, outperforming lead-acid batteries' typical 500-1,000 cycles and enabling economic viability over 10-20 year project lifespans in high-cycling scenarios like arbitrage or ancillary services.[161] Efficiency remains high at round-trip values of 85-95%, though lower volumetric energy density (around 250-300 Wh/L) is less penalizing in stationary contexts where space constraints are minimal compared to mobile uses.[162] Ongoing cost reductions, projected to dip below $200/kWh installed by 2030, further bolster LFP's role in supporting variable renewable penetration, as evidenced by its growing share in utility-scale projects amid global BESS capacity expansions.[163]Industrial and Portable Uses
Lithium iron phosphate (LFP) batteries are widely adopted in industrial material handling equipment, particularly electric forklifts, pallet jacks, and reach trucks, due to their thermal stability, resistance to overcharge, and ability to support opportunity charging without significant degradation.[164] These batteries enable continuous operation across multiple shifts, with cycle lives often exceeding 3,000 to 4,000 cycles at 50% depth of discharge, compared to lead-acid batteries' typical 1,500 cycles, reducing downtime and maintenance needs like watering or equalization.[165] In 2025, manufacturers such as Green Cubes Technology introduced LFP packs specifically engineered for this sector, emphasizing ruggedized designs for harsh environments and fast charging times under 2 hours.[166] For portable applications, LFP batteries power tools and equipment requiring high discharge rates and durability under repeated charge-discharge cycles, such as cordless drills and saws, where their inherent safety mitigates risks of thermal runaway common in higher-energy-density chemistries.[167] They also serve in uninterruptible power supplies (UPS) for data centers and critical infrastructure, offering 4 times the lifespan of lead-acid alternatives and consistent performance under high loads, with capacities scalable from 12V modules upward.[168] Portable power stations increasingly incorporate LFP cells for off-grid uses like camping or emergency backup, benefiting from over 3,000 cycles and wide temperature tolerance from -10°C to 50°C, as seen in units with 2,000+ Wh capacities retaining 80% health post-cycling.[169] While less prevalent in compact consumer electronics due to volumetric energy density limitations (typically 120-160 Wh/kg versus 200+ Wh/kg for alternatives), LFP's prevalence grows in safety-prioritized portable scenarios.[170]Environmental Considerations
Lifecycle Emissions and Impacts
The production phase of lithium iron phosphate (LFP) batteries, encompassing raw material extraction and cell manufacturing, accounts for a significant portion of their lifecycle greenhouse gas (GHG) emissions, typically ranging from 55 to 56 kg CO₂ equivalent per kWh of capacity under current global supply chains dominated by coal-intensive electricity in China.[171] This cradle-to-gate footprint is lower than that of nickel-manganese-cobalt (NMC) batteries, which emit approximately 77-79 kg CO₂ eq/kWh, primarily due to LFP's use of abundant iron and phosphate instead of energy-intensive nickel and cobalt processing.[171] Lithium extraction contributes notably, with mining operations in regions like Australia representing up to 17% of LFP's production emissions, though overall material sourcing for LFP exerts less pressure on critical mineral supply chains compared to cobalt-dependent chemistries.[171] In full cradle-to-grave assessments for applications like electric vehicles or energy storage, manufacturing constitutes about 50% of total LFP emissions, higher proportionally than the 15% for NMC batteries, as LFP packs have lower energy density and thus require more material per kWh delivered over their lifetime.[172] The operational phase emissions depend heavily on the electricity grid's carbon intensity; for a 1 kWh LFP storage system, electricity use during manufacturing and charging drives 40% of global warming potential (GWP), totaling around 90.8 kg CO₂ eq, with potential reductions of up to 36% by 2050 under decarbonized scenarios.[173] End-of-life recycling can mitigate impacts by recovering materials, though current processes increase fossil resource use slightly by 1% while lowering GWP through avoided virgin production.[173] Beyond GHGs, LFP batteries exhibit varied environmental impacts across categories. For a 1 kWh system, ecotoxicity in freshwater reaches 7,170 CTUe, largely from anode materials (83%), while terrestrial eutrophication stands at 1.22 kg N eq, driven by anode (48%) and electricity (26%) contributions.[173] Acidification and ionizing radiation are also notable, with the latter at 8.87 kBq U-235 eq, predominantly from electricity (59%).[173] These impacts stem from phosphate mining's potential for nutrient runoff and lithium brine extraction's high water consumption, though LFP avoids the toxicity and habitat disruption associated with cobalt mining in NMC batteries. Lifecycle analyses highlight that cleaner production grids could reduce acidification by 25% and fossil resource scarcity by 33%.[173][171] Overall, LFP's lower reliance on scarce metals positions it favorably for reduced geopolitical and ecological risks in raw material sourcing, provided recycling rates improve.[172]Mining and Raw Material Extraction
Lithium iron phosphate (LFP) batteries require extraction of lithium, iron, and phosphorus, with the latter derived from phosphate rock; these materials form the cathode structure LiFePO₄. Lithium is primarily sourced from hard-rock mining of spodumene ore in Australia, which accounts for over 60% of global supply, or from brine evaporation in the Lithium Triangle of South America.[132] Hard-rock processing involves open-pit mining followed by crushing, roasting at 1000–1100°C to convert spodumene to leachable β-form, and acid leaching to yield lithium carbonate or hydroxide suitable for battery-grade purity.[173] Brine extraction entails pumping lithium-rich saltwater from salars, evaporating it in ponds over 12–18 months, and precipitating lithium chemicals, though this method consumes vast water volumes—up to 500,000 liters per ton of lithium—exacerbating aquifer depletion in arid regions.[174] Iron for LFP cathodes is obtained from abundant iron ore deposits via open-pit or underground mining, followed by beneficiation, smelting in blast furnaces to pig iron, and refining to battery-grade ferrous compounds exceeding 99% purity through electrolysis or chemical precipitation.[127] Global iron ore production exceeds 2.5 billion tons annually, with major suppliers like Australia and Brazil employing mature techniques that minimize per-ton impacts compared to rarer metals, though operations generate tailings, dust emissions, and habitat fragmentation.[173] Phosphorus extraction relies on phosphate rock mining, predominantly strip methods in Florida, Morocco, and China, where 223 million tons were mined in 2020 from reserves estimated at 71 billion tons; the ore is crushed, beneficiated via flotation, and treated with sulfuric acid to produce phosphoric acid for LFP synthesis.[132] Environmental impacts of these extractions include significant land disturbance and waste generation: lithium hard-rock mining disrupts up to 100 hectares per operation with acid tailings, while brine methods contribute to 65% of regional water stress in extraction areas.[174] Phosphate mining yields 150 million tons of phosphogypsum waste annually, often radioactive due to co-extracted uranium, leading to soil contamination and radon emissions if not managed in lined stacks.[175] Iron ore extraction, though less resource-constrained, releases sediments into waterways, acid mine drainage, and contributes to 7–10% of global mining-related CO₂ via energy-intensive processing.[127] Approximately 40% of an LFP battery's cradle-to-gate carbon footprint stems from these mining and refining stages, driven by electricity use in ore concentration and chemical purification, though LFP's avoidance of cobalt and nickel reduces reliance on high-impact artisanal mining in regions like the Democratic Republic of Congo.[174][173] Rising LFP demand, projected to consume 10–20% of lithium output by 2030, intensifies pressure on finite phosphate reserves and water resources, necessitating improved beneficiation efficiencies to curb waste.[132]Recycling and End-of-Life Management
Lithium iron phosphate (LFP) batteries at end-of-life are typically managed through reuse in second-life applications, direct regeneration of cathode materials, or full recycling via hydrometallurgical or pyrometallurgical processes, with hydrometallurgy favored for its high lithium recovery rates exceeding 90% under optimized conditions, lower energy use, and reduced environmental impact compared to high-temperature methods.[176][177] Direct regeneration, which restores degraded LiFePO4 cathodes via low-temperature relithiation, achieves material recovery efficiencies of up to 95% while avoiding the need for complete disassembly, making it more cost-effective for LFP than for nickel- or cobalt-based chemistries due to the absence of high-value scarce metals.[178][179] Challenges in LFP end-of-life management include low economic incentives from abundant and inexpensive constituent materials—iron, phosphorus, and lithium—resulting in global lithium recovery rates from spent LFP batteries below 1% as of recent assessments, far lower than for other lithium-ion types, compounded by inefficient collection systems and the preference for second-life repurposing in stationary storage where batteries retain 70-80% capacity.[180][181] Overall lithium-ion battery recycling rates reached approximately 59% globally in 2023, but LFP-specific rates lag due to these factors, with U.S. processing of 95,000 tons of lithium-ion batteries that year including minimal LFP-targeted recovery.[182][183] Emerging electrochemical and liquid-phase hydrometallurgical techniques address these issues by enabling selective lithium extraction at ambient temperatures with recovery yields of 85-96%, producing byproducts like iron phosphate fertilizers and reducing emissions by up to 4.6 kg CO2 equivalent per kg recycled, though scalability remains limited by pretreatment costs for black mass separation.[184][185][177] Second-life pathways extend usability, with LFP batteries showing 18% lower emissions and 58% higher profits when optimized for reuse before recycling, prioritizing state-of-health thresholds around 70-80% capacity retention to minimize waste.[181] Regulatory frameworks, such as U.S. EPA guidelines, emphasize proper collection to prevent hazardous waste contamination, but enforcement gaps persist for LFP volumes projected to surge with electric vehicle adoption.[186]Limitations and Criticisms
Energy Density Constraints
Lithium iron phosphate (LFP) batteries exhibit lower gravimetric energy density compared to nickel-manganese-cobalt (NMC) and other cathode chemistries, typically ranging from 90 to 160 Wh/kg at the cell level, while NMC cells achieve 150 to 260 Wh/kg.[90] At the pack level, LFP systems deliver approximately 20% less energy per unit mass than equivalent NMC packs, constraining their suitability for weight-sensitive applications.[131] Recent commercial advancements, such as fourth-generation LFP materials with higher compaction density, have pushed cell-level densities toward 160-180 Wh/kg, yet these remain below NMC benchmarks.[187]| Cathode Type | Gravimetric Energy Density (Wh/kg, cell level) | Key Reference |
|---|---|---|
| LFP | 90-160 | [90] |
| NMC | 150-260 | [90] |