Tailored Li-ion battery electrodes and electrolytes for extreme condition operations

Abstract

This review examines recent advancements in lithium-ion battery (LIB) technology for extreme conditions, focusing on applications in electric vehicles, renewable energy, defense, and remote sensing. We explore innovative electrode and electrolyte designs that enhance performance at extreme temperatures, addressing challenges like electrolyte freezing and increased impedance. The review highlights the development of novel electrolytes, including high-entropy formulations, and fast-charging electrodes. Emphasizing sustainability and resilience, we aim to inspire near-future research in LIBs capable of meeting demands for extreme operational scenarios, including space exploration. This analysis provides insights and perspectives on improving LIB performance and reliability across challenging applications.

Introduction

Lithium-ion batteries (LIBs), originally brought to market by Sony in 1991, have become the cornerstone of modern electrical energy storage¹. LIBs are utilized in various applications, including electric vehicles (EVs), portable devices, military applications, and even space missions. Each application imposes multiple performance requirements². These requirements include variations in power demand, external pressure, and particularly temperature (Fig. 1). Low temperatures severely impair LIB performance by slowing ion transfer, increasing internal resistance, and reducing electrolyte conductivity. Below 0 °C, these effects intensify, leading to energy loss, capacity decline, and potential battery failure, underscoring the need for advanced cold-resistant designs^1,3. To address these challenges, external heating mechanisms, such as Radioisotope Heater Units (RHUs) and electric warm-up heaters, have been utilized to keep the battery within an operational temperature range (Fig. 2a)^4,5,6. While effective in preventing electrolyte solidification and sustaining functionality, this approach has several limitations. In practice, secondary or external heating systems keep the batteries functional at the expense of substantially increased weight, maintenance cost, complexity of system and energy consumption—factors that are especially critical in space exploration or other environments where resources are limited^4,5,7. Considering these drawbacks, it is crucial to develop LIBs capable of operating independently in low-temperature environments. These batteries eliminate the need for external heating, simplify system designs, and enhance energy efficiency, ensuring reliable performance under extreme conditions, which is the focus of this review(Table 1).

Fig. 1: Operational temperature ranges for lithium-ion batteries.

Across diverse applications. Star indicates Purdue’s breakthrough innovation in electrode-electrolyte combination enabling LIBs operation at −100 °C.

Fig. 2: Electrolyte solvation and interfacial phenomena in ultra-cold lithium-ion battery systems.

a Schematic comparison of battery operation strategies at ultra-low temperature. Scheme 1, warming during both charge and discharge. Scheme 2, warming only during charging. Scheme 3, enabling battery operation without external warming. The right panel illustrates lithium plating behavior: strong Li⁺-solvent binding in conventional electrolytes leads to dendritic lithium plating, whereas weak Li⁺-solvent binding in the proposed electrolyte promotes homogeneous lithium plating⁶. Adapted with permission from ref. ⁶. © Springer Nature. b Representation of lithium-ion diffusion from the electrolyte to the graphite anode¹³. Adapted with permission from ref. ¹³. © American Chemical Society. c Illustration of degradation mechanisms at the anode-electrolyte interface in lithium-ion batteries at low temperature²⁶. Adapted with permission from ref. ²⁶. © Elsevier.

Table. 1 Summary of recently reported electrode and electrolyte strategies for improving lithium-ion battery performance under subzero temperatures

Challenges in extreme conditions, low temperature operation

LIBs are composed of four primary elements: a cathode, an anode, electrolyte, a porous separator that electronically separates electrodes but allows ion migration. The fundamental operation of LIBs is based on the reversible intercalation and deintercalation of lithium ions and their transfer between the anode and cathode during the charging and discharging cycles. For instance, the most common LIB system is composed of a transition metal oxide cathode, a graphite anode, and an electrolyte of lithium salts dissolved in an organic solvent. During the charging process, Li⁺ ions are extracted from the cathode material, diffuse through the electrolyte, and intercalate between the graphite layers of the anode^8,9. This process is facilitated by the movement of lithium ions through the electrolyte, which usually consists of a lithium salt dissolved in organic solvents¹⁰.

However, the performance of LIB significantly degrades at low temperatures, limiting its application in extreme environments such as polar regions and high altitudes. Below 0 °C, several processes simultaneously impact battery performance. First, bulk ionic conductivity decreases, limiting the transport of lithium ions between the electrodes¹¹. Second, interfacial charge transfer resistance increases, meaning that electrochemical redox reactions at the electrode surface, particularly the reduction of lithium ions, occur more slowly¹². Third, there is a slower diffusion of lithium ions into the electrode material, another transport limitation¹³. While these factors are all influenced by low temperatures, they are not inherently coupled effects and can be addressed individually. Reduced bulk ionic conductivity and slower diffusion at interfaces limit the availability of Li⁺ for redox reactions, already hindered by increased charge transfer resistance. Together, these processes reduce the capacity of the battery by limiting its ability to store and transfer charge at low temperatures. The solid-state diffusion of lithium-ion within the graphite anode, which is the process of intercalation mentioned earlier, becomes particularly very sluggish, resulting in incomplete intercalation during charging and a higher risk of lithium plating (Fig. 2b)^13,14. This phenomenon can cause the formation of dendrites, which can penetrate the separator and lead to short circuits, posing serious safety risks^15,16,17.

Operating LIBs in low-temperature conditions poses significant challenges due to the limitations of conventional materials and electrochemical processes. Reduced lithium-ion mobility arises as carbonate-based electrolytes, like ethylene carbonate (EC), become viscous and lose ionic conductivity in the cold. With EC comprising 30–50% of commercial electrolytes and a high melting point of 36 °C, these mixtures often freeze around −20 °C, halting ion transport and drastically degrading battery performance in sub-zero environments¹⁸. Pol et al.¹⁹ at Purdue University has achieved a breakthrough in low-temperature LIB technology, developing an electrode-electrolyte combination that enables LIBs to operate at −100 °C (indicated with a star in Fig. 1). To support this innovation, Purdue created the Extreme Low Temperature System (ELTS), a device capable of testing cells at temperatures down to −175 °C, demonstrating significant discharge capacities in Li₄Ti₅O₁₂ (LTO)||Li cells even at −100 °C²⁰.

This review is systematically divided into four comprehensive sections to provide a holistic understanding of advancements and challenges in LIBs for low-temperature operations: (i) anode—exploring material innovations, surface modifications, and structural optimizations to enhance lithium-ion transport and mitigate performance degradation in extreme conditions; (ii) cathode—examining strategies to improve stability, conductivity, and compatibility with electrolytes under sub-zero temperatures; (iii) electrolyte—focusing on the development of low-freezing-point liquid electrolytes, high-entropy systems, and additives to maintain ionic conductivity and thermal safety; and (iv) solid-state battery—discussing the potential of solid electrolytes as a transformative solution for low-temperature LIBs, addressing their unique properties, challenges, and future prospects.

Tailored electrode materials

The performance of LIBs at low temperatures is severely constrained by kinetic limitations, particularly those related to the solid-state diffusion of lithium ions within the electrode materials and the reduction in their electrical conductivity^3,21,22. These limitations are critical as they directly handicap the ability of LIB to charge, store, and deliver energy efficiently under cold conditions.

Solid-state diffusion refers to the movement of lithium ions through the crystalline lattice of the electrode material, mainly graphite²³. As the temperature drops, the diffusion coefficient of lithiated and delithiated states decreases, indicating that diffusion becomes increasingly limited at lower temperatures, contributing to the sluggish kinetics observed in battery performance²⁴. The sharp decline in the diffusion coefficient (D) for both lithiated and delithiated graphite highlights the limitation and severely hindered lithium ion mobility, leading to impaired battery performance (Fig. 3a)^24,25. Moreover, the insufficient diffusion rate increases the likelihood of lithium plating on the anode surface, especially at high charging currents, which can lead to dendrite formation and potentially short-circuiting the battery, leading to safety risk^6,26,27.

Fig. 3: Temperature-dependent Li⁺ transport limitations and morphological stability of antimony anode under subzero conditions.

a The lithium-ion chemical diffusion coefficient depends on temperature²⁴. b Resistance depends on temperature²⁴. Panels (a) and (b) adapted with permission from ref. ²⁴. © Elsevier. c Galvanostatic cycling of half cells with 1,3 dioxolane/dimethoxyethane (DOL/DME) electrolyte at various temperatures with Antimony anode²⁸. d SEM image for Antimony anode after cycling at various temperatures left side is at 20 °C and right side is at −40 °C²⁸. Panels (c) and (d) adapted with permission from ref. © Wiley.

Beyond diffusion limitations, low temperatures also influence the electrode-electrolyte interface, further exacerbating kinetic challenges. The solid electrolyte interphase (SEI), which forms on the anode surface, becomes more resistive at reduced temperatures, limiting lithium-ion transport. Studies have shown that SEI formation at lower temperatures results in an unstable and thickened interphase that increases charge-transfer resistance, making lithiation and delithiation processes significantly less efficient (Fig. 3b)²⁸. Additionally, lithium plating is more likely to occur at the anode due to sluggish lithium-ion kinetics, further contributing to performance degradation.

At room temperature, graphite exhibits high conductivity, around 10^2 S/cm, which is crucial for the efficient transport of electrons and facilitates intercalation and de-intercalation of lithium ions. However, as the temperature drops, the available thermal energy decreases, leading to reduced electron mobility and a subsequent drop in conductivity^21,29. The decreased conductivity also increases the internal resistance of the electrode, making it more challenging to achieve high charging and discharging rates²⁴. Furthermore, the high overpotential at low temperatures has been observed to significantly affect charge-discharge behavior, causing notable deviations from expected electrochemical profiles and reducing the usable capacity of the battery²⁸. The combination of high charge-transfer resistance, increased overpotential, and poor solid-state diffusion at low temperatures underscores why widely used graphite anodes struggle as an anode material in extreme conditions.

To address these limitations, alloy-based anodes have gained attention due to their significantly higher theoretical capacities compared to graphite. Materials such as silicon, tin, and antimony offer up to ten times the capacity of graphite, making them attractive candidates for high-energy-density LIBs³⁰. However, their performance at low temperatures presents unique challenges. Alloying materials undergo significant volume expansion and contraction during lithiation and delithiation, which can lead to particle fracture, electrode pulverization, and continuous SEI growth, all of which contribute to rapid capacity fade^31,32,33,34. At low temperatures, these structural stresses become more pronounced due to the slower kinetics of lithium-ion transport and undesired phase transformation processes.

Among alloying materials, antimony has demonstrated superior low-temperature performance compared to silicon and tin. Unlike silicon, which suffers from extremely low electrode potential and high overpotentials that lead to lithium plating at subzero temperatures, antimony exhibits a relatively higher equilibrium potential (~0.9 V vs. Li/Li⁺)²⁸. This higher potential reduces the risk of lithium plating and enables better capacity retention. At −40 °C, lithium-antimony alloys can achieve a first-cycle specific capacity of 440 mAh g^−1, nearly 80% of its room-temperature capacity, highlighting their promise for cold-temperature applications (Fig. 3c)²⁸. At 0 °C, antimony maintains stable cycling with only a modest drop in specific capacity compared to room temperature²⁸. Also, antimony retains a substantial portion of its initial capacity (~80%) over 50 cycles at –20 °C, even without nanostructuring or conductive additives. The similar morphologies suggest that cycling at different temperatures does not significantly alter the surface area of the electrodes in a way that would impact impedance (Fig. 3d)²⁸. However, despite its advantages, antimony still experiences significant capacity fade over cycling at low temperatures, likely due to SEI instability and kinetic limitations associated with charge transfer and diffusion.

Silicon, despite its high theoretical capacity, demonstrates the poorest low-temperature performance among alloy materials due to its low lithiation potential and severe kinetic barriers. Even at 0 °C, silicon anodes show minimal lithiation on initial cycles, as the voltage quickly reaches the 0 V cutoff, preventing proper intercalation²⁸. In some cases, extended cycling at low temperatures allows gradual activation of silicon, but this comes at the cost of high polarization and severe capacity degradation. Overall, while alloy-based anodes offer promising alternatives to graphite for low-temperature LIBs, their practical implementation is hindered by kinetic constraints, phase transformation challenges, and structural degradation.

These challenges highlight the limitations of conventional graphite electrodes as well as alloy-based anodes in low-temperature applications, where maintaining high conductivity and efficient lithium-ion diffusion is essential for reliable battery performance. While graphite suffers from sluggish solid-state diffusion and poor conductivity at sub-zero temperatures, alloy-based materials face additional challenges such as large volume expansion, phase transformation instability, and high overpotentials that can accelerate capacity fade^24,25,28. To address these issues, ongoing research is focused on developing new materials and modifying existing ones to enhance their performance in cold environments^19,35,36.

Recent advancements in LIB technology have focused on developing alternative electrode materials and design strategies to overcome low-temperature limitations. These efforts include investigating novel materials with improved ionic and electronic transport properties, as well as enhanced structural stability, to enable high-performance LIBs under extreme conditions.

Anode materials

To overcome the kinetic limitations of conventional graphite and alloy-based anodes at low temperatures, researchers have explored alternative electrode materials with improved lithium-ion transport, enhanced charge transfer kinetics, and stable structural integrity under extreme conditions. Recent advances have focused on modifying electrode materials to reduce solid-state diffusion resistance, engineering electrolytes to stabilize the SEI, and developing amorphous materials that suppress structural degradation at subzero temperatures.

One promising strategy involves modifying layered transition metal compounds to facilitate lithium-ion diffusion. Liu et al.³⁵ developed a MoSâ‚‚/carbon (MoS₂/C) hybrid anode which incorporates enlarged interlayer spacing to alleviate the lithium-ion diffusion bottleneck and enhance electronic conductivity. The MoS₂ layers enable facile lithium-ion intercalation and conversion reactions, while the carbon matrix improves electron transport, leading to significant improvements in low-temperature performance. As a result, the MoSâ‚‚/C hybrid anode delivers a discharge capacity of 854.3 mAh g^−1 at −20 °C at 100 mA g^−1, retaining 72.8% of its room-temperature capacity (Fig. 4a). Even at a high current density of 3 A g^−1, a capacity of 140.9 mAh g^−1 is maintained, demonstrating excellent rate performance. In situ TEM and GITT analyses revealed that, at low temperature, lithiation proceeds through a domain-by-domain reaction multistep insertion-conversion process that initiates at the outer edges and gradually advances inward (Fig. 4b, c). This is distinct from the two-step mechanism observed at room temperature, where intercalation into MoS₂ fully precedes conversion. The domain-by-domain process contributes to improved lithium-ion mobility by progressively expanding the MoS₂ layers during lithiation, which maintains continuous ionic pathways into the interior. This mechanism not only facilitates faster Li⁺ transport but also ensures higher MoS₂ utilization and minimizes structural degradation. Correspondingly, GITT measurements show that the Li⁺ diffusion coefficient in the MoS₂/C hybrid is 2–3 times higher than in pure MoS_2, particularly during the discharge process. These findings underscore the importance of structural engineering in achieving high lithium-ion mobility and robust performance at low temperatures.

Fig. 4: Electrochemical and structural evaluation of advanced anode materials for low-temperature lithium-ion batteries.

a Galvanostatic cycling of half-cell with MoS₂/C anode and 1 M LiPF₆ in ethylene carbonate/dimethyl carbonate (EC:DMC = 1:1, volume ratio) at RT and −20 °C with various rates³⁵. b, c In-situ TEM captures the morphological and structural evolution of MoSâ‚‚/C during lithium transport at −20 °C. The yellow-circled areas highlight the positions after lithiation, while the red arrows indicate the initiation of the lithiation edge³⁵. Panels (a–c) adapted with permission from ref. ³⁵. © Elsevier. d long cycling performance of graphite anode with CPME electrolyte at −20 °C¹¹.XPS spectra from the graphite anode with reference electrolyte (1 M LiPF₆ in EC : DEC (1 : 1)) and 1 M LiFSI in cyclopentyl methyl ether (CPME) electrolyte in its delithiated state after 10 cycles: (e) F 1s¹¹ (f) C 1s¹¹. g Charge-discharge curves of the graphite anode in 1 M LiFSI/CPME electrolyte at −40 °C, measured at a current density of 0.005C¹¹. Panels (d–g) adapted with permission from ref. ¹¹. © Royal Society of Chemistry. Cyclic voltammetry (CV) of iron hydroxyl selenide (Fe(OH)Se) || Li cell with CPME electrolyte. h CV curves at 25 °C under different scan rates ranging from 0.1 to 1 mV s^{−1 16}. i Capacity contribution at various scan rates¹⁵. j Cycling performance of Fe(OH)Se) || Li half cells with 1 M LiFSI/CPME electrolyte at −60, −80, and −100 °C with different rates¹⁵. Panels (h–j) adapted with permission from ref. ¹⁵. © Elsevier.

Beyond modifying electrode materials, electrolyte engineering is a crucial approach to improving low-temperature performance. Graphite, despite being the most widely used anode material, suffers from severe kinetic limitations under subzero conditions, primarily due to sluggish lithium-ion intercalation, high charge-transfer resistance, and unstable SEI formation^24,25,26,27. These challenges necessitate electrolyte systems that not only remain in a liquid state at low temperatures but also facilitate efficient lithium-ion transport and ensure a stable interface for lithiation.

For instance, 1,3 dioxolane/dimethoxyethane (DOL/DME) is often considered a suitable low-temperature electrolyte due to its low freezing points (DOL: −95 °C, DME: −58 °C), which prevent electrolyte solidification²⁸. However, despite remaining in a liquid state, DOL/DME fails to support graphite lithiation at −20 °C²⁸. This poor performance is attributed to the high Li⁺ desolvation energy, which slows down lithium-ion release from the solvated state and limits charge-transfer kinetics⁶. The SEI formed in DOL/DME electrolytes contains highly resistive organic components at low temperatures, impeding lithium-ion transport and increasing the risk of lithium plating, which leads to capacity loss and safety concerns. In contrast, Ramasamy et al.¹¹ demonstrated that cyclopentyl methyl ether (CPME)-based electrolytes enable graphite to retain significant capacity even at −40 °C, underscoring the critical role of electrolyte properties in improving low-temperature performance. Unlike DOL/DME, CPME facilitates faster lithium-ion desolvation, ensuring that lithium ions are efficiently released from the solvated state and transported to the anode surface. This difference is crucial, as sluggish lithium-ion desolvation increases charge-transfer resistance, limiting the lithiation process. CPME has a weaker solvation structure that allows lithium ions to desolvate more easily, reducing charge-transfer resistance. Additionally, CPME promotes the formation of a LiF-rich SEI, which remains ionically conductive at low temperatures and provides a stable interfacial layer for lithiation and delithiation (Fig. 4e, f). The electrolyte, consisting of 1 M LiFSI in CPME, demonstrates excellent cycling stability, achieving 355 mAh g^−1 for the first cycle over 350 cycles with 84% capacity retention at 1 C. Additionally, the electrolyte enables remarkable low-temperature performance, delivering 370, 337, and 330 mAh g^−1 at 0, −10, and −20 °C, respectively, at 0.1 C (Fig. 4d). Even at −40 °C, the graphite anode maintains a capacity of 274 mAh g^−1, with no electrolyte freezing observed (Fig. 4g). These findings highlight the potential of CPME-based electrolytes as a promising solution for extending LIB operation to subzero temperatures.

In addition to layered materials and electrolyte innovations, amorphous transition metal compounds have emerged as promising candidates for extreme low-temperature applications. Kim et al.¹⁵ developed an amorphous multiple anionic transition metal compound anode to enable LIB operation in extreme low-temperature environments down to −100 °C. By utilizing iron hydroxyl selenide (Fe(OH)Se) with a layered structure, the anode provides enhanced ion diffusion pathways and reduced energy barriers for conversion reactions. Paired with a cyclopentyl methyl ether (CPME)-based electrolyte, which maintains efficient Li⁺ conduction at subzero temperatures, the Fe(OH)Se-based LIBs demonstrate exceptional performance over a broad temperature range. The cell achieves 974.7 mAh g^−1 at 1.0 A g^−1 at room temperature, 285.2 mAh g^−1 at −80 °C at 0.025 A g^−1, and 1066.9 mAh g^−1 at 45 °C at 0.2 A g^−1 (Fig. 4j). Even at −100 °C, the LIB remains operable, highlighting the feasibility of amorphous multiple anionic electrode materials for extreme condition energy storage.

Fe(OH)S exhibits a unique combination of pseudocapacitive behavior and phase transformation, both of which contribute to its superior electrochemical performance. Its pseudocapacitive nature enables fast, surface-controlled charge storage, circumventing the sluggish solid-state diffusion that limits conventional intercalation-based anodes at low temperatures. The cyclic voltammetry (CV) results at different scan rates demonstrate a dominant capacitive-controlled lithium storage process, indicated by the high b-values (~1.0) calculated using the power law ${i}_{p}={{av}}^{b}$ (Fig. 4h)³⁷. The capacity contribution analysis further reveals that capacitive-controlled storage dominates the overall lithium storage process across all scan rates (Fig. 4i). Beyond its pseudocapacitive behavior, Fe(OH)Se undergoes a distinct phase transformation during cycling, forming a Fe(OH)â‚“/FeSe_y heterostructure. This transformation contributes to cycling stability by reducing charge transfer resistance and enhancing lithium-ion transport, as confirmed by ex situ XPS and TEM analyses, which reveal the heterostructure formation after the initial cycles. While pseudocapacitive behavior and the amorphous structure primarily enable efficient lithium storage at ultra-low temperatures, the phase transformation further stabilizes the electrode structure, mitigating degradation over prolonged cycling. Together, these properties make Fe(OH)Se a promising candidate for next-generation LIB anodes designed for extreme environmental conditions.

Together, these advancements illustrate diverse yet complementary strategies for improving LIB performance under subzero conditions. While Liu et al.¹¹ tackled lithium-ion diffusion limitations by modifying MoSâ‚‚ structures, Ramasamy et al.¹¹ optimized electrolyte composition to enhance SEI stability, and Kim et al.¹⁵ developed an amorphous electrode material with superior ion storage capabilities. By integrating structural modifications, electrolyte engineering, and novel anode materials, researchers are paving the way for lithium-ion batteries that can reliably operate in extreme environments.

Cathode materials

Just as low-temperature LIB performance is constrained by the sluggish kinetics of anode materials, cathodes also suffer from significant degradation in cold environments due to increased charge-transfer resistance, suppressed lithium-ion diffusion, and reduced electronic conductivity. Conventional cathode materials, such as layered transition metal oxides (LiCoO₂, NCM, and NCA) and polyanionic compounds (LiFePO₄, Li₃V₂(PO₄)₃), exhibit severe capacity fading and high polarization at subzero temperatures. These effects are exacerbated by sluggish lithium-ion intercalation, slow charge-transfer processes, and undesired side reactions at the cathode-electrolyte interface. One strategy to mitigate these issues involves electrolyte optimization.

Ramanujapuram et al.³⁸ demonstrated the exceptional low-temperature performance of LIB cathodes in aqueous electrolytes, highlighting their superior charge-transfer characteristics compared to conventional organic electrolytes. By using high-concentration aqueous salt solutions (LiNO₃, Li₂SO₄, and LiCl), the study revealed that intercalation cathodes exhibit minimal charge-transfer resistance even at subzero temperatures. As a result, LiCoO₂ (LCO) retained 72% of its room-temperature capacity at −40 °C in saturated LiCl electrolyte, whereas organic electrolytes failed to support any meaningful capacity below −20 °C (Fig. 5a). Furthermore, the study identified resistances as the primary limiting factor at low temperatures, with aqueous electrolytes significantly mitigating this issue (Fig. 5b, c). These findings demonstrate the exceptional potential of high-concentration aqueous electrolytes for improving LIB performance in extreme cold environments, primarily by minimizing charge transfer and bulk electrolyte resistance at subzero temperatures, offering a promising alternative to conventional organic-based systems.

Fig. 5: Cathode and pseudocapacitive material strategies for low-temperature lithium-ion storage.

a Cycling data of lithium cobalt oxide (LCO) with various electrolyte at various temperature³⁸. b, c Temperature-dependent comparison of electrolyte and surface layer resistances for aqueous (saturated LiCl) and organic (1 M LiPF₆ in 1:1 EC:DEC) electrolyte systems³⁸. Panels (a), (b), and (c) adapted with permission from ref. ³⁸. © Wiley. d Long cycling performance of Li₃V₂(PO₄)₃ (LVP) and LVP/C + YPO₄ cells at −40 °C with 0.5C³⁹. e Charging and discharging curve for Li₃V₂(PO₄)₃ (LVP) and LVP/C + YPO₄ cells at −40 °C³⁹. f Cycling performance with various rates³⁹. Cyclic voltammetry (CV) of a niobium tungsten oxide (NbWO)|| Li cell with 1.5 M LiFSI in a mixed electrolyte of tetrahydrofuran, 1,1,2,2-tetrafluoroethyl 2,2,3,3-tetrafluoropropyl ether, and fluoroethylene carbonate (1.5-TTF). Panels (d–f) adapted with permission from ref. ³⁹. © Wiley. g CV curve at scan rates ranging from 0.05 to 2.0 mV s−¹¹⁹, (h) log(ip) versus log(v) plots showing the relationship between peak current and scan rate¹⁹. i Galvanostatic voltage curve of a NbWO‖Li cell with 1.5 M LiFSI in a cyclopentyl methyl ether electrolyte (1.0-CPME) at −100 °C under a C/30 rate¹⁹. Panels (g), (h), and (i) adapted with permission from ref. ¹⁹. © Wiley.

Beyond electrolyte modifications, surface engineering of cathode materials has emerged as an effective strategy for improving low-temperature performance. Tong et al.³⁹ demonstrated an effective strategy to enhance the low-temperature performance of LIBs by introducing a binary surface coating on the Li₃V₂(PO₄)₃ (LVP) cathode. Unlike conventional approaches that focus on electrolyte modifications, this method improves both high-rate capability and low-temperature stability without altering the electrolyte formulation. The in-situ formation of YPOâ‚„ nanoparticles within an amorphous carbon layer reduces unwanted side reactions at high voltages and enhances interfacial charge transfer kinetics. As a result, the LVP/C + YPO₄ cathode delivers a room-temperature discharge capacity of 159 mAh g^−1, retaining 153 mAh g^−1 at −20 °C (89.1%) and 130 mAh g^−1 at −40 °C (75.7%) (Fig. 5d, e). Furthermore, the cathode exhibits high-rate capability, maintaining 101 mAh g^−1 at 50 C, demonstrating its ability to sustain ultra-fast charge-discharge cycles (Fig. 5f). These findings highlight the potential of binary surface coatings in advancing LIB performance for extreme low-temperature applications and high-power devices. Although this study centers on sodium-ion batteries, the design principles may offer useful parallels for lithium-based systems operating under extreme conditions. A notable example is a high-entropy NASICON-type cathode, Na_3.45V_0.4Fe_0.4Ti_0.4Mn_0.45Cr_0.35(PO₄)₃, synthesized via ultrafast high-temperature shock treatment. This polyanionic phosphate material, comprising five transition metals, exhibited a stable solid-solution behavior and multielectron redox activity, which contributed to its wide-temperature operation⁴⁰. In hard carbon (HC) | | HE-Na_3.45TMP full-cell evaluations, it delivered 108.1 mAh g^−1 at −40 °C, relative to 137.2 mAh^−1 at room temperature, and maintained 73.7 mAh g^−1 at −50 °C, along with 92.8% capacity retention after 90 cycles. These results were obtained using 1 M NaPF₆ in diglyme (DGM) as the electrolyte. While not directly applicable to lithium-ion chemistries, the use of entropy stabilization and fast ion-conducting frameworks could inspire future cathode designs for low-temperature LIBs.

In addition to modifying conventional intercalation cathodes, pseudocapacitive cathode materials have gained attention for their ability to support fast charge-storage mechanisms. Unlike layered oxides that rely on bulk lithium-ion diffusion, pseudocapacitive materials utilize surface redox reactions, allowing for much higher charge-transfer kinetics and better performance at low temperatures⁴¹. Recently, Kim et al.¹⁹ demonstrated a groundbreaking novel approach to address the performance limitations of Li-ion batteries in extreme cold environments for the first time, by combining pseudocapacitive-type niobium tungsten oxides (NbWO) electrode material with specially designed cyclopentylmethyl ether (CPME) based electrolytes, enabling battery cycling at temperatures as low as −100 °C with capacities of approximately 75 mAh g^−1 (Fig. 5i). The homogeneous distribution of Nb and W atoms in NbWO materials and multielectron redox (Nb⁵⁺/Nb⁴⁺ and W⁶⁺ /W⁵⁺) facilitates Li⁺ diffusion by inhibiting Li ordering during charge-discharge cycles (Fig. 5g). The distinct structural attributes of NbWO, including large pentagonal tunnels and an open framework, facilitate rapid lithium-ion diffusion and accommodate significant pseudocapacitive behavior (Fig. 5g, h), ensuring highly reversible charge storage even at subzero temperatures⁴¹. Experimental results demonstrate the potential of NbWO-based batteries for extreme cold environments, with functional performance observed at temperatures as low as −120 °C (Fig. 1). In a pouch-type configuration, the NbWO‖Li cell exhibited a discharge capacity exceeding 47 mAh g^−1 at −100 °C under a C/40 rate.

Thus, improving cathode performance under subzero conditions requires a combination of strategies, including electrolyte optimization, surface coatings to enhance charge transfer, and the development of novel pseudocapacitive materials. While conventional layered oxides continue to face severe challenges in cold environments, emerging approaches—such as disordered transition-metal oxides and pseudocapacitive compounds—offer promising pathways to achieving stable lithium-ion battery operation at extreme temperatures.

Advanced electrolyte systems

The electrolyte plays a crucial role in determining the performance of LIBs, particularly in extreme cold environments where charge transfer kinetics and ion transport become severely restricted. Conventional carbonate-based electrolytes suffer from increased viscosity, poor lithium-ion conductivity, sluggish desolvation kinetics, and unstable SEI and cathode electrolyte interphase (CEI) formation at low temperatures. These limitations lead to high overpotentials, lithium plating, and significant capacity degradation, making it challenging to maintain stable battery operation under subzero conditions. To address these issues, researchers have pursued multiple electrolytes engineering strategies, including solvent and cosolvent modifications to lower viscosity and enhance lithium-ion mobility, salt and anion engineering to optimize charge transfer and interfacial stability, dual-ion battery concepts to mitigate desolvation barriers, and solvation structure optimization to reduce desolvation energy barriers and facilitate efficient lithium-ion diffusion^6,42,43,44.

Solvent and cosolvent modifications

One of the primary barriers to low-temperature LIB performance is the high viscosity and freezing points of conventional carbonate-based electrolytes, such as ethylene carbonate (EC) and dimethyl carbonate (DMC). At subzero temperatures, these electrolytes exhibit poor lithium-ion mobility and high polarization, leading to capacity loss and low Coulombic efficiency. To address this issue, researchers have explored low-viscosity ether-based and fluorinated solvents that maintain fluidity at subzero temperatures while ensuring stable lithium-ion transport.

Cheng et al.⁴⁵ developed a low-temperature lithium-metal battery that operates stably at −40 °C by tailoring the electrolyte chemistry with a weakly solvating ether-based solvent system. Specifically, they used 1 M LiFSI with 1 wt% LiNO₃ in a mixed solvent of 2-methyltetrahydrofuran (MTHF) and tetrahydrofuran (THF) at a 6:1 volume ratio, enabling a weakly coordinated solvation structure and high ionic conductivity. The resulting electrolyte exhibited 3.44 mS cm^−1 ionic conductivity at −40 °C and facilitated the formation of a uniform, anion-derived LiF-enriched SEI that suppressed dendrite growth. As a result, symmetric Li||Li cells achieved ultra-high current densities up to 10 mA cm^−2 with low polarization and stable cycling for over 1000 hours. In full-cell tests, the Li||CoSeO_x battery delivered 416.2 mAh g^−1 at −40 °C, retaining approximately 56% of its RT capacity, and maintained 84% capacity retention over 100 cycles, underscoring the potential of solvation structure regulation and SEI optimization for enabling ultrafast and long-lasting operation in extreme cold. Although the study was conducted on a sodium-ion system, the electrolyte strategy may offer guidance for lithium-ion battery development under extreme temperatures. Cai et al.⁴⁶ formulated an electrolyte using 0.8 M NaPF₆ in EC:EMC (3:7, v/v) with 1% sodium difluorophosphate (NaDFP) and 1.5% trimethylsilyl butyrate (TMSB), which helped stabilize both the SEI and CEI. In a full cell with a NaNi_0.33Fe_0.33Mn_0.33O₂ (NFM) cathode and hard carbon anode, the NB-based system maintained stable cycling at −30 °C, delivering a capacity of 697 mAh at 1 C. While developed for sodium-ion batteries, this additive-assisted solvation tuning may offer useful insights for improving electrolyte performance in lithium-ion systems operating in subzero environments.

Holoubek et al. ⁶ introduced a weakly solvated electrolyte strategy to optimize Li⁺ desolvation kinetics and enhance lithium metal battery (LMB) performance at ultra-low temperatures. This study demonstrates that by replacing conventional solvent-separated ion pair (SSIP) electrolytes (DOL/DME) with a contact-ion pair (CIP) electrolyte (diethyl ether, DEE), Li⁺-solvent interactions are weakened, resulting in faster desolvation and improved interfacial charge transfer. Molecular dynamics (MD) simulations and spectroscopic analysis reveal that DEE reduces the Li⁺ desolvation energy barrier from −414 kJ mol^−1 (DOL/DME) to −280 kJ mol^−1 (Fig. 6a), facilitating rapid Li-ion transport even at −60 °C. In contrast, the DOL/DME system retains a stronger Li⁺-solvent coordination, increasing the desolvation energy and leading to sluggish charge transfer and dendritic Li deposition at low temperatures (Fig. 6a). As a result, the DEE-based electrolyte enables stable cycling of Li‖SPAN full cells, where a high-loading sulfurized polyacrylonitrile (SPAN) cathode paired with a limited Li anode delivers 519 mAh g^−1 at −40 °C (84% of room-temperature capacity) and 474 mAh g^−1 at −60 °C (76%), while DOL/DME electrolytes exhibited rapid failure due to increased charge transfer resistance (Fig. 6b). Additionally, Coulombic efficiency remains above 98% even at −60 °C, whereas the control electrolyte suffers from severe capacity fade due to sluggish desolvation and dendritic Li plating (Fig. 6c, d). These findings highlight the crucial role of electrolyte solvation structure in enabling ultra-low-temperature lithium metal batteries and provide a molecular-level design framework for optimizing Li⁺ coordination environments.

Fig. 6: Solvent engineering for low-temperature lithium-ion batteries.

a Proposed desolvation mechanisms and Li⁺/solvent binding energies derived from quantum chemistry simulations for 1 M LiFSI in 1,3-dioxolane/1,2-dimethoxyethane (DOL/DME) on the left and 1 M LiFSI in diethyl ether (DEE) on the right⁶. b long cycling performance of Li‖sulfurized polyacrylonitrile (SPAN) half cells at −60 °C⁶. Scanning electron microscopy (SEM) images of Cu after Li plating (c) 1 M LiFSI DOL/DME⁶, (d) 1 M LiFSI DEE⁶. Panels (a–d) adapted with permission from ref. ⁶. © Springer Nature. e Raman spectra of electrolytes and their corresponding pure solvents⁴⁴. f Schematic representation of interactions between the LMA and electrolytes, highlighting Li⁺ solvation and SEI chemistry⁴⁴. g Charge/discharge profile for LiNi_0.8Co_0.1Mn_0.1O₂ (NCM811) ‖Li at low temperatures⁴⁴. h Low temperature cycling performance⁴⁴. Panels (e–h) adapted with permission from ref. ⁴⁴. © Wiley.

Similarly, Kim et al.⁴⁴ developed a tetrahydrofuran (THF)-derived localized high-concentration electrolyte (LHCE) designed to leverage weakly coordinated ion-solvent interactions, reducing lithium-ion desolvation barriers. The THF-based electrolyte formulation was designed to leverage weakly coordinated ion-solvent interactions, reducing the lithium-ion desolvation barrier (Fig. 6e), which is a critical factor in subzero temperature performance. The electrolyte, composed of 1.5 m LiFSI in a solvent mixture of THF, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE), and fluoroethylene carbonate (FEC) in a 3:6:1 volume ratio, maintained an AGG-rich solvation structure while achieving low viscosity and a high lithium-ion transference number, enabling efficient Li⁺ transport in extreme cold environments. THF exhibited a low freezing point (−109 °C) and high lithium-ion transference number, facilitating lithium-ion mobility even in extreme cold environments (Fig. 6f). By stabilizing the SEI with an inorganic-rich interphase containing LiF and Liâ‚‚O—both known for their high ionic conductivity and ability to reduce interfacial impedance—the THF-based LHCE enabled stable cycling of Li‖NCM811 full cells, retaining 75% and 64% of their room-temperature capacity at −20 °C and −40 °C, respectively (Fig. 6g, h) and highlighting the effectiveness of low-freezing-point solvents in extreme cold environments.

Additionally, Zhang et al.⁴⁷ introduced a monofluoride ether-based electrolyte, which enhanced lithium-ion solvation while maintaining oxidative stability, to enable fast-charging and low-temperature operation of lithium metal batteries (LMBs), addressing the challenges of ionic conductivity and interfacial stability. This study demonstrates that the introduction of bis(2-fluoroethyl) ether (BFE) as a solvent enhances Li⁺ transport by forming Li-F and Li-O tridentate coordination chemistries, improving ionic conductivity while maintaining oxidation stability. Compared to difluoro- and trifluoro-substituted ethers, the monofluoro (-CHâ‚‚F) group optimizes the solvation structure, resulting in a high ionic conductivity of 8 mS cm^−1 at 30 °C and stable Li metal cycling with a 99.75% Coulombic efficiency (Fig. 7a). The Li‖NCM811 coin cell with Bis(2-fluoroethyl) ether (BFE) electrolyte achieves capacities of 90, 139, 160, 181, 202, and 226 mAh g^−1 at temperatures of −60, −30, −20, 0, 30, and 60 °C (Fig. 7b). The BFE electrolyte with an areal capacity of 1.75 mAh cm^−2 enables to achieve stable cycling at −30 °C for over 150 cycles with 90% capacity retention (Fig. 7c). Furthermore, a 320 mAh Li||NCM811 pouch cell delivers a high specific energy of 426 Wh kg^−1with 80% capacity retention after 200 cycles at 30 °C. These findings demonstrate the potential of fluorinated ether-based electrolytes for low-temperature applications .

Fig. 7: Electrolyte engineering strategies for cathode compatibility and low-temperature cycling.

a Coordination behavior of monofluoride, difluoro, and trifluoro groups in the molecular design of BFE, enabling simultaneous Li⁺ coordination through one Li-O and two Li-F interactions⁴⁷. b Cycling performance of Li‖NCM811 at various temperatures with 2,2-difluoroethyl-2-fluoroethyl ether (DFE), Bis(2-fluoroethyl) ether (BFE), 1,2-dimethoxyethane (DME) electrolytes⁴⁷. c Long-term cycling performance of Li‖NCM811 coin cells with BFE and DEE electrolytes at −30 °C⁴⁷. Panels (a–c) adapted with permission from ref. ⁴⁷. © Springer Nature. d Electrostatic potential (ESP) maps of the analyzed ether molecules, where red, green, and white spheres denote O, C, and H atoms, respectively⁴³. e Long-term cycling performance of a 300 mAh double-sided Li‖NCM811 pouch cell with 1.8 M LiFSI dipropyl ether (DPE) electrolyte under 30 PSI pressure⁴³. The cell was initially cycled at 30 mA twice, followed by extended cycling at 30 mA charge and 90 mA discharge⁴³. f X-ray photoelectron spectroscopy (XPS) spectra of C1s, F 1s, and O1s for NCM811 cathode⁴³. g Wide temperature performance of 1.8 M DPE electrolyte, shown through voltage profiles of Li‖NCM811 coin cell at varying temperatures⁴³. Panels (d–g) adapted with permission from ref. ⁴³. © Springer Nature. h Ionic conductivity of electrolyte with different content of isobutyronitrile (IBN) at different temperatures⁴⁸. i Discharge curve of LiCoO₂||graphite pouch cells with 8.33 vol% EC, 31.67 vol% EMC, and 60 vol% iBN with 1 M LiPF₆ (iBN-60) electrolyte at different low temperatures⁴⁸. j Charging/discharging curves of LiCoO₂||graphite pouch cells at low temperature⁴⁸. Panels (h–j) adapted with permission from ref. ⁴⁸. © Wiley.

Li et al.⁴³ developed a non-polar ether-based electrolyte to enhance the high-voltage stability of LMBs, addressing the electrochemical instability of conventional ether electrolytes (Fig. 7d). By using dilute dipropyl ether (DPE) based electrolyte with lithium bis(fluorosulfonyl) imide (LiFSI) salt, the study demonstrates a controlled decomposition mechanism that favors the formation of a robust inorganic rich CEI while preventing free solvent oxidation (Fig. 7f). This selective degradation pathway stabilizes the electrolyte-electrode interface, enabling long-term cycling at 4.3 V in Li||NCM811 pouch cells, where a specific discharge capacity retention of 74% is maintained after 150 cycles at 0.33 and 1 mA cm^−2 at 25 °C (Fig. 7e). Even at −40 °C, the Li||NMC811 cell maintains a capacity of 125 mAh g^−1 (Fig. 7g). Additionally, the electrolyte effectively mitigates aluminum current collector corrosion, further improving battery longevity. These findings highlight a new approach for stabilizing ether electrolytes in high-voltage LMBs, paving the way for improved energy storage solutions. The effectiveness of this system arises from its tailored solvation chemistry. In the low-polarity DPE environment, Li⁺ cations preferentially coordinate with multiple FSI^- anions to form aggregated clusters, rather than with solvent molecules. Density functional theory (DFT) calculations showed that these aggregated structures have higher HOMO energy levels than free ether solvents, making them more prone to oxidation. As a result, these clusters decompose first during charging, which initiates the formation of a uniform, inorganic-rich CEI composed largely of LiF and sulfur-containing species. Additionally, molecular dynamics simulations of the electric double layer (EDL) revealed that these ion aggregates accumulate at the cathode surface, effectively displacing free ether molecules and shielding them from direct contact with the electrode. This rearrangement of species within the EDL contributes to interfacial stability by kinetically favoring the decomposition of anions over solvents. In this way, the electrolyte achieves high-voltage compatibility without relying on high salt concentrations or fluorinated solvents, instead using interfacial and solvation design to regulate CEI formation and suppress oxidative degradation.

Luo et al.⁴⁸ developed a low-viscosity, weak-solvation electrolyte to enable LIB operation at −70 °C, addressing the severe ionic transport limitations of conventional electrolytes in extreme cold conditions. By introducing isobutyronitrile (iBN) as a cosolvent, the electrolyte—composed of 8.33 vol% EC, 31.67 vol% EMC, and 60 vol% iBN (denoted as iBN-60)—achieves a high ionic conductivity of 1.152 mS cm^−1 at −70 °C. This high conductivity, obtained by increasing iBN content in the base electrolyte (1 M LiPF₆ in EC:EMC = 3:7 by volume), significantly enhances lithium-ion desolvation kinetics and lowers charge transfer resistance, thereby improving low-temperature electrochemical performance (Fig. 7h). As a result, LiCoO₂||graphite pouch cells with the iBN-60 electrolyte deliver discharge capacities of 1273.9 mAh at 25 °C, 1178.2 mAh at −40 °C, 912.5 mAh at −60 °C, and 875.0 mAh at −70 °C, corresponding to 92% and 68.7% capacity retention at −40 °C and −70 °C, respectively, thereby demonstrating excellent low-temperature performance (Fig. 7i). Additionally, LiCoO₂||graphite pouch cells with the iBN-60 electrolyte demonstrate stable cycling at −20 °C and −40 °C, delivering discharge capacities of 1130 mAh at −20 °C (0.2 C/0.2 C) and 798 mAh at −40 °C (0.1 C/0.1 C), highlighting the effectiveness of electrolyte under deep subzero conditions (Fig. 7j). These findings highlight a promising electrolyte design strategy to enhance the operational temperature range of LIBs for extreme environments.

Salt and anion engineering

Beyond solvent modifications, the selection of lithium salts and counter-anions significantly affects ion transport and SEI stability at low temperatures. LiPF₆-based electrolytes, commonly used in commercial LIBs, exhibit poor solubility, high desolvation barriers, and sluggish charge transfer under subzero conditions. To improve charge transfer kinetics, researchers have explored high-salt-concentration formulations and multi-anion coordination strategies.

One strategy to improve electrolyte performance in cold environments is the incorporation of functional additives that optimize solvation properties, ionic conductivity, and interfacial stability. Lv et al.⁴⁹ introduced a modified electrolyte system by adding butyl acrylate (BA) and ethylene carbonate (EC) in the base electrolyte which is a mixture of Dimethyl carbonate (DMC) and ethyl methyl carbonate (EMC) in a 3:5 weight ratio, which enhanced both solubility and lithium-ion transport properties. The optimized electrolyte formulation, combined with a LiBF₄ (LBF) and LiPF₆ (LPF) mixed salt system, facilitated stable charge transfer while forming a thin, LiF-rich CEI layer that minimized resistance at the cathode interface. As a result, a lithium metal||NCM811 cell retained a discharge capacity of 173.1 mAh g^−1 at −10 °C, decreasing to 119.3 mAh g^−1 at −40 °C with 0.3 M LBF (DMC:EMC = 3:5 (W/W) + 16%(V) BA + 10%(V) EC + 0.3 M LBF + 0.7 M LPF), significantly outperforming conventional electrolyte formulations (Fig. 8a). These discharge tests were conducted after charging at room temperature, highlighting the ability of electrolyte to support lithium-ion transport during low-temperature discharge. Moreover, the electrolyte demonstrated stable cycling at −40 °C, maintaining 85 mAh g^−1 even after extended use, highlighting the potential of LiF-rich CEI layers in mitigating charge-transfer resistance at low temperatures (Fig. 8b, c).

Fig. 8: High-concentration and salt-engineered electrolyte strategies for stabilizing low-temperature interphases.

a Discharge curves of Li‖NCM811 coin cells with different electrolytes at −40 °C (charged at room temperature)⁴⁹. b Electrochemical impedance spectroscopy (EIS) spectra of Li‖NCM811 coin cells with different electrolytes⁴⁹. c Charge/discharge voltage profile for 0.3 M LBF electrolyte at −40 °C⁴⁹. Panels (a–c) adapted with permission from ref. ⁴⁹. © Elsevier. d High-resolution transmission electron microscopy (HRTEM) image of graphite anode after cycling with HSCE (5 M LiFSI THF) electrolyte at room temperature for secondary electrolyte interphase (SEI) morphology⁵⁰. e XPS spectra of CVE (1 M LiPF₆ in EC/DEC (1:1, v/v)) and HSCE, showing deconvoluted C 1s, O 1s, and F 1s signals⁵⁰. f Long-term cycling performance of Li‖graphite half cells at low temperatures of 0 and −20 °C⁵⁰. g long-term cycling performance of LiNi_0.6Co_0.2Mn_0.2O₂ (NCM622)||graphite full cells at low temperatures of −20 and −40 °C⁵⁰. Panels (d–g) adapted with permission from ref. ⁵⁰. © American Chemical Society. h Charge-discharge profiles of the Li‖NCM811 cell using TA electrolyte at −40 to −60 °C, with the electrolyte composed of 0.5 M LiPF₆ + 0.5 M LiTFSI + 0.1 M LiNO₃ in a 1:9 vol% mixture of fluoroethylene carbonate (FEC) and tetrahydrofuran (THF)⁵¹. i Binding energies of Li⁺ with various anions⁵¹. Panels (h) and (i) adapted with permission from ref. ⁵¹. © Wiley.

Additionally, Kim et al.⁵⁰ investigated high-salt-concentration electrolytes (HSCEs) as an alternative strategy to enhance low-temperature charge transfer and reduce the desolvation energy barrier. The study analyzed concentrations from 0.5 M to 5.0 M, showing a transition from solvent-separated ion pairs (SSIPs) at low concentrations to contact-ion pairs (CIPs) and anion aggregates (AGGs) at higher concentrations. By formulating an electrolyte with 5 M LiFSI in THF, they demonstrated that an anion-derived LiF-rich SEI could be achieved, with a sub-5 nm thickness, reducing interfacial resistance while maintaining stable lithium-ion transport (Fig. 8d, e). For low temperature cycling performance, the study tested 5.0 M LiFSI in THF, demonstrating significantly enhanced capacity retention. In graphite||Li half cells, the electrolyte enabled a discharge capacity of 323 mAh g^−1 at 0 °C, which remained nearly unchanged from room temperature. At −20 °C, the cell retained 300 mAh g^−1, while at −40 °C, it maintained 84 mAh g^−1, far exceeding the performance of conventional carbonate-based electrolytes, which failed below −20 °C (Fig. 8f). Even in LiNi_0.6Co_0.2Mn_0.2O₂||graphite full cells, the electrolyte maintained a capacity of 70 mAh g^−1 at −40 °C, achieving 43% capacity retention compared to room temperature (Fig. 8g). Additionally, the cell demonstrated stable cycling, remaining operational for over 50 cycles under these extreme conditions.

Liang et al.⁵¹ introduced a novel electrolyte design strategy for LMBs that addresses the challenges of low-temperature performance and fast charging. By leveraging the competitive coordination of ternary anions (PF₆^−, TFSI^-, and NO₃^−), the researchers developed an anti-freezing electrolyte with rapid Li⁺ desolvation kinetics. Density functional theory (DFT) calculations indicate that Li⁺ exhibits a binding energy of −4.62 eV when interacting with anions in the ternary-anion (TA) system, which includes PF₆^−, TFSI^−, and NO₃^− (Fig. 8i). This weakened binding facilitates faster ion transport, contributing to a high ionic conductivity of 3.39 mS cm^−1 at −60 °C. When paired with an NCM811 cathode and a lithium metal anode, the TA electrolyte enables stable cycling with 86.74% capacity retention after 200 cycles at 25 °C and delivers a specific capacity of 103.85 mAh g^−1 at −60 °C, compared to 213 mAh g^−1 at room temperature (both at 0.1 C) (Fig. 8h). This work shows a remarkable improvement in low-temperature cycling stability compared to conventional single-anion electrolytes .

Multi-Solvent Systems

Electrolyte performance in LIBs is significantly influenced by its solvent composition, as different solvents impact lithium-ion mobility, electrolyte viscosity, and SEI formation. Conventional single-solvent electrolytes, such as EC-based systems, suffer from high viscosity, poor ionic conductivity, and freezing at subzero temperatures, limiting their usability in extreme environments. To address these limitations, researchers have developed multi-solvent electrolyte systems that strategically combine solvents with varying polarities, viscosities, and dielectric constants to optimize lithium-ion solvation and charge transfer across a wide temperature range. These multi-solvent systems enhance ion transport, reduce freezing points, and improve interfacial stability, making them a promising approach for next-generation LIBs designed for low-temperature applications.

A major advantage of multi-solvent systems is their ability to form an optimized solvation shell around lithium ions, reducing desolvation energy barriers and improving ion mobility⁵². The inclusion of low-viscosity and fluorinated solvents significantly lowers the freezing point of the electrolyte, ensuring stable operation in subzero conditions⁴⁷. Adams et al.⁵³ investigated a ternary fluorinated electrolyte (F-FFN) composed of fluoroethylene carbonate (FEC), methyl (2,2,2-trifluoroethyl) carbonate (FEMC), and nonafluorobutyl methyl ether (NONA), which exhibited superior lithium-ion transport properties at subzero temperatures. The optimized formulation, using lithium bis(fluorosulfonyl)amide (LiFSI) salt, facilitated the formation of a LiF-rich SEI, which stabilized lithium-ion transport and minimized overpotential during low-temperature cycling. Compared to conventional carbonate-based electrolytes, the F-FFN electrolyte demonstrated superior charge-transfer kinetics, with a charge-transfer activation energy (E_a,CT) of 55.71 kJ/mol, significantly lower than the 64.3 kJ/mol observed in commercial electrolytes. The LiFePO₄ (LFP)||Li coin cells retained 61% of their room-temperature capacity at −50 °C, whereas commercial carbonate-based electrolytes retained only 25% at −25 °C. The ability of fluorinated multi-solvent systems to lower desolvation barriers and improve lithium-ion mobility highlights their potential for extreme-temperature applications.

Additionally, Packard et al.⁵⁴ investigated the role of intermediate electrolytes (IEs) in their gradient localized high-concentration electrolyte (LHCE) system, designed to enhance lithium-ion transport and stability at low temperatures. In this context, intermediate electrolytes refer to the coordinating solvents with dielectric constants between the extremely polar fluoroethylene carbonate (FEC) and the non-polar diluent nonafluorobutyl methyl ether (NONA). These IEs—and either diethyl carbonate (DEC), ethyl methyl carbonate (EMC), or dibutyl carbonate (DBC)—were incorporated to create a step-down polarity gradient that improved miscibility, enabled higher diluent content (up to 37.5% by volume), and suppressed phase separation issues observed in previous LHCE designs. Their study tested multiple intermediate electrolytes with varying dielectric constants and steric effects to determine which formulation best facilitates smooth lithium-ion desolvation, low charge-transfer resistance, and stable SEI formation. Their study introduced a two-step electrolyte structure, where the main electrolyte combined FEC as a highly polar solvent, FEMC as an intermediate solvent, and NONA as a low-polarity diluent, collectively referred to as F-FFN. Among the tested IEs, the F-FDFN-based electrolyte (DEC-based) exhibited the lowest charge-transfer resistance (E_a,CT = 59.6 kJ/mol) and SEI resistance (E_a,SEI = 46.2 kJ/mol), leading to faster lithium-ion transport and improved interfacial stability at subzero temperatures. Compared to F-FEFN (EMC-based) and F-FBFN (DBC-based) electrolytes, which showed higher activation energies and weaker lithium-ion coordination, F-FDFN enabled superior lithium-ion mobility, reduced overpotentials, and stable SEI formation. Cycling testing in LFP||Li coin cells confirmed that F-FDFN provided the best low-temperature performance, retaining 68% of its room-temperature capacity at −50 °C, corresponding to a discharge capacity of 109.2 mAh g^−1. This combination effectively balanced ionic conductivity, charge-transfer efficiency, and interfacial stability, making it the most suitable electrolyte system for ultra-low-temperature lithium-ion batteries.

Solid-state battery capable of low-temperature cycling

The limitations of conventional liquid-electrolyte-based LIBs at low temperatures, including severe ionic transport restrictions, high interface resistance, and lithium dendrite formation, have motivated significant research into all-solid-state batteries (ASSBs) as a promising alternative^55,56. ASSBs replace flammable liquid electrolytes with solid-state electrolytes (SSEs), which provide improved thermal stability, wider electrochemical stability windows, and enhanced mechanical properties that mitigate dendrite growth^57,58,59. However, achieving stable operation at subzero temperatures remains a significant challenge due to the intrinsic ionic transport limitations in solid electrolytes, interfacial resistance at electrode-electrolyte contacts, and reduced electrochemical kinetics at extreme cold conditions^60,61.

In SSEs, lithium-ion transport relies entirely on bulk and interfacial conduction, which differs from the solvation-based mechanisms in liquid electrolytes^62,63. In polycrystalline inorganic SSEs, such as sulfides and garnets, lithium ions move through a network of grains, where grain boundaries often serve as barriers that impede transport^62,64,65,66. These interfaces exhibit higher resistance, particularly under cold conditions when ionic conductivity drops significantly^59,62. This problem is exacerbated in thick composite electrodes, where tortuosity and poor percolation of the SSE network limit effective ion mobility^55,67,68.

Recent advancements in SSE design, interfacial engineering, and electrolyte composition modifications have demonstrated significant improvements in low-temperature performance. One of the primary challenges of ASSBs at low temperatures is the substantial increase in interface impedance and the degradation of lithium-ion transport across the solid-solid interface^69,70. Unlike conventional liquid electrolytes, where lithium-ion solvation/desolvation occurs at the electrolyte-electrode interface, SSEs rely entirely on bulk ionic conduction, which is significantly influenced by grain boundaries and interfacial contact⁷¹. Hong et al.⁵⁹ developed an ASSB tailored for extreme cold conditions by utilizing an amorphous solid-state electrolyte (SSE) xLi₃N–TaClâ‚… (1 ≤ 3x ≤ 2), which exhibits a high ionic conductivity of 5.91 mS cm^−1 at 3x = 1.25 at 25 °C (Fig. 9a, b). Compared to conventional liquid electrolyte-based lithium-ion batteries, ASSBs avoid viscosity-related limitations at subzero temperatures. However, their overall ionic transport remains constrained by solid-state diffusion and interfacial resistance at solid-solid interfaces. The designed Li-In|LGPS–L_1.25NTCl | LiCoOâ‚‚ ASSB achieves discharge capacities of 183.19 mAh g^−1 at −10 °C, 164.8 mAh g^−1 at −30 °C, and 143.78 mAh g^−1 at −40 °C when cycled at 18 mA g^−1. Furthermore, at −30 °C, the battery retains 83.50% of its capacity after 100 cycles, demonstrating long-term cycling stability. Notably, the ASSB exhibits a discharge capacity of 51.94 mAh g^−1 at −60 °C with the same rate and remains operational for over 200 h under these extreme conditions (Fig. 9c, d). These findings highlight the potential of amorphous SSE-based ASSBs for reliable energy storage in ultra-low-temperature environments.

Fig. 9: Solid-state and polymer electrolyte approaches for extreme-temperature lithium battery.

a The all-solid-state batteries (ASSB) consists of a LiCoOâ‚‚ (LCO) cathode, a solid-state electrolyte (SSE), an interface layer, and a Li-In anode. This structural design enhances mechanical and chemical stability while facilitating efficient ionic transport within the SSE and at the electrode/SSE interface, even under extreme cold conditions⁵⁹. b Ionic conductivities of amorphous xLi₃N-TaCl₅ (1 ≤ 3x ≤ 2) solid-state electrolyte at 25 °C⁵⁹ c, d Charge-discharge profiles of ASSBs at −60 °C with cutoff potentials of 3.0 V and 4.5 V vs. Li⁺/Li at 18 mA g^−1 for the Li-In | Li₁₀ GeP₂S₁₂ (LGPS)-Li_1.25N_0.417-TaCl₅ (L_1.25 NTCl)|LCO configuration⁵⁹. Panels (a–d) adapted with permission from ref. ⁵⁹. © Springer Nature. e Schematic illustration of the SEI on the Li metal electrode (top left) and degradation mechanisms in a Li‖NCM811 cell (top right) with a non-aqueous carbonate-based electrolyte with 1 M LiPF₆ in EC:DMC 1:1 v/v, compared to SEI formation (bottom left) and suppression of degradation (bottom right) in a Li‖NCM811 cell using the designed polymer electrolyte, made with 1,3,5-trioxane (TXE) monomer: fluoroethylene carbonate (FEC): 2,2,2-Trifluoro-N, N-dimethylacetamide (FDMA) 5:3:1 w/w and 1 M lithium difluoro(oxalato)borate (LiDFOB), developed in this study⁷⁴. f SEM image of NCM811 particle after cycling. The top left is using the designed polymer electrolyte and the bottom left is non-aqueous carbonate-based electrolyte. TEM image of NCM811 particle after cycling to understand CEI morphology. The top right is using the designed polymer electrolyte, and the Bottom right is non-aqueous carbonate-based electrolyte⁷⁴. g XPS spectra of C 1s, F 1s, B 1s, and Ni 2p for NCM811 cathodes using the designed polymer electrolyte and a non-aqueous carbonate-based electrolyte⁷⁴. h Voltage profiles during charge and discharge of the Li‖NCM811 pouch cell with the polymer electrolyte at −30 °C⁷⁴. Panels (e–h) adapted with permission from ref. ⁷⁴. © Springer Nature.

A complementary approach to improving the low-temperature performance of ASSBs is the development of quasi-solid-state polymer electrolytes, which integrate polymeric matrices with ionic conductors to achieve better interfacial contact and higher ionic conductivity compared to purely inorganic SSEs^72,73. Li et al.⁷⁴ reported a quasi-solid-state polymer electrolyte with high ionic conductivity to enable stable low-temperature operation of LMBs. The electrolyte, synthesized via in situ polymerization of a 1,3,5-trioxane (TXE) -based precursor, achieves an ionic conductivity of 2.2 × 10^−4 S cm^−1 at −20 °C. The designed polymer electrolyte, composed of 1,3,5-trioxane (TXE) monomer, fluoroethylene carbonate (FEC), and 2,2,2-trifluoro-N,N-dimethylacetamide (FDMA) in a 5:3:1 w/w ratio with 1 M lithium difluoro(oxalato)borate (LiDFOB), facilitates the formation of a dual-layered SEI on the Li metal anode, which enhances interfacial charge transfer and mitigates dendrite growth (Fig. 9e–g). As a result, a Li||NCM811 coin cell retains over 75% of its room-temperature capacity (~151 mAh g^−1) at −20 °C when cycled at 20 mA g^−1 and demonstrates excellent stability with 99.1% capacity retention over 200 cycles. Furthermore, the polymer electrolyte enables stable cycling of Li||NCM811 pouch cells at −30 °C, delivering a specific capacity of 94 mAh g^−1 at a current density of 20 mA g^−1 (Fig. 9h), demonstrating its potential for improving lithium metal battery performance in extreme cold environments.

In summary, while ASSBs offer promising advantages for low-temperature applications, their performance is currently constrained by two key factors: the need for high intrinsic and effective ionic conductivity, and stable interfaces that prevent continuous decomposition. Advances such as amorphous sulfide SSEs and dual-layered SEI-forming polymer electrolytes show promise in overcoming these limitations and highlight the direction of future design principles for robust ASSBs in cold environments.

Conclusion and perspectives

The development of LIBs for extremely low-temperature environments has made significant progress through advancements in tailored electrode materials, electrolyte formulations, and interfacial engineering. Despite these improvements, achieving stable, high-performance LIBs under subzero conditions remains a challenge due to sluggish lithium-ion transport, high charge-transfer resistance, and the risk of lithium plating. This review has explored recent innovations in electrode materials, electrolyte systems, and solid-state batteries that address these challenges. By leveraging novel material design and electrolyte engineering strategies, researchers are paving the way for next-generation LIBs capable of reliable operation in extreme environments, including polar regions, high-altitude applications, and space missions.

To accelerate the commercialization and practical deployment of low-temperature LIBs, several key advancements are required. The development of low-freezing-point electrolytes with enhanced ionic conductivity through additives such as fluorinated compounds is crucial for balancing performance and thermal safety⁴⁷. Optimized electrode designs, including doped or coated anodes and cathodes, are necessary to improve ion transport and reduce resistance, particularly in pouch cells where thermal management plays a critical role. Additionally, implementing active and passive thermal management strategies, such as self-heating systems and insulation techniques, can help maintain electrolyte stability and operational efficiency under extreme conditions.

High-entropy electrolytes (HEEs) have emerged as a promising avenue for enhancing low-temperature LIB performance. By leveraging multi-component electrolyte formulations, HEEs improve ion mobility, reduce charge-transfer resistance, and stabilize interfaces under subzero conditions^75,76,77. The integration of nanostructured materials offers further potential for enhancing charge-transfer kinetics, though attention must be given to mitigating volumetric energy loss and first-cycle capacity fade.

Designing effective low-temperature LIBs requires careful consideration of several key factors. Solvent selection is critical, with a focus on physical and chemical properties that ensure thermal safety. While pseudocapacitive electrode materials offer improved lithium transport at low temperatures, they may compromise volumetric energy density. In-situ characterization tools (Cryo-TEM, NMR etc.) are essential for understanding reaction mechanisms. Cell design, including the choice between pouch and cylindrical formats with different sealing materials, significantly impacts ultralow temperature performance. Current testing equipment is inadequate, with moisture-induced issues affecting results. Future advancements in low-temperature LIB technology hinge on improved design approaches and more reliable testing methods. Considering the need for sustainable energy storage from solar and wind sources, future research should expand low-temperature battery electrode/electrolyte discovery and thermal safety testing efforts to include sodium and potassium ion batteries.

Sustainability and scalability remain critical considerations for future LIB advancements. Prioritizing eco-friendly materials, developing efficient recycling strategies, and establishing cost-effective manufacturing processes will be essential for enabling widespread commercial adoption despite the higher costs associated with advanced battery components. By combining advancements in electrode engineering, electrolyte formulations, and solid-state battery technology, the path forward for low-temperature LIBs is promising. The continued development of high-entropy electrolytes, pseudocapacitive anodes, and robust solid-state designs will extend operational temperature ranges and facilitate breakthroughs in electric vehicles, aerospace, defense, and extreme-environment applications. Multidisciplinary research efforts integrating materials science, electrochemistry, safety and advanced characterization techniques will be key to unlocking the full potential of next-generation LIBs for extreme conditions.