Battery Cycle Life Research Articles

Improvement of rate capability and cycle life of Na-NiCl2 battery via designing a graphene anchoring porous nickel nanostructures as cathode

The integration of renewable energy with advanced energy storage technologies is essential. The sodium-based batteries, particularly sodium-nickel chloride (Na-NiCl2) batteries, show promise due to the abundance and low redox potential of sodium (−2.7 V vs. SHE). Despite their advantages in terms of cost, safety, and high efficiency, the improvement of rate and cycling performance of Na-NiCl2 batteries remains a challenge. To address this issue, a Ni nanostructure-supported reduced graphene oxide (RGO) composite is synthesized and combined with NaCl to serve as the cathode material for Na-NiCl2 batteries. Benefiting from the strong anchoring function of RGO, the growth of Ni is inhibited. As a result, the obtained cathode exhibits a notable specific capacity of 132.7 mAh/g at a high rate of 0.6C, along with excellent Coulombic efficiency of 100 % over 500 cycles and high energy efficiency (95.8 %). In addition, the outstanding conductivity, high specific surface area and abundant pore distribution of Ni@RGO contribute to enhanced conversion reaction and ion diffusion, and thus promoting rate capability. In contrast, the pure Ni nanosheets-based (Ni NSs) cathode is subjected to serious grain growth, which leads to poor rate performance and rapid capacity fading. By introducing conductive framework of RGO and constructing porous Ni nanostructure, the rapid electrons transport and diffusion of ions is achieved, and thus presenting the exceptional electrochemical properties.

Carbon emission assessment of lithium iron phosphate batteries throughout lifecycle under communication base station in China

The demand for lithium-ion batteries has been rapidly increasing with the development of new energy vehicles. The cascaded utilization of lithium iron phosphate (LFP) batteries in communication base stations can help avoid the severe safety and environmental risks associated with battery retirement. This study conducts a comparative assessment of the environmental impact of new and cascaded LFP batteries applied in communication base stations using a life cycle assessment method. It analyzes the influence of battery costs and power structure on carbon emissions reduction. Results indicate: When consuming the same amount of electricity in a cascaded battery system (CBS), LFP batteries with a retirement state of health (SOH) range between 76.5 % and 90.0 % can reduce 30.3 % of the global warming potential (GWP) compared to new batteries. From the perspective of battery costs, when the price ratio of new to old batteries is greater than 31.0 %, the GWP of batteries retired at 70.0 % SOH is higher than that of new batteries. As the proportion of renewable energy sources in the power structure increases, the GWP of new batteries in 2035 is 15.0 % lower than in 2020. For batteries retired at 80.0 % SOH, their GWP decreases by 12.3 % compared to 2020. This study offers a new approach to determining the retirement point for LFP batteries from an environmental perspective, promoting carbon emission reduction throughout the entire battery life cycle and the sustainable development of the transportation sector.

Sulphur/functionalized graphene composite as cathode for improved performance and life cycle of lithium-sulphur batteries

Over the past years, significant advantages have been introduced to upgrade the performance of lithium-sulfur battery (Li-S) batteries since their prototype in the 1960s. Due to high theoretical energy density and cost efficiency, Li-S batteries have obtained great attention and have made great progress in the last few years. In this work, we developed the sulfur-attached few-layer graphene composite (S/FLG), sulfur-attached functionalized few-layer graphene using acetic acid (S/FLG-COOH) and sulfur-attached functionalized few-layer graphene using strong acid H2SO4 and HNO3 (S/FLG-OH) as a cathode material with high sulfur loading. The material’s structure is confirmed through XRD. The surface morphology is confirmed through SEM and elemental composition has been obtained through EDAX. The functional groups are confirmed through FTIR. The defect level and number of layers are confirmed through Raman characterization with an excitation laser wavelength of 532 nm. The electrochemical performance of three cathodes is also identified through EIS, CV, and GCD characterization. Meanwhile, highly developed defects and edges found in the functionalization of few-layer graphene using the strong acid (H2SO4 and HNO3) which consists of a hydroxyl functional group (FLG-OH) serve as polysulfide reservoirs to mitigate the shuttle effect. Among these cathodes, S/FLG-OH shows a high specific capacitance of 157.4 F g−1 and when applied as a cathode host on a coin cell it obtained a voltage of about 2.6 V. Well-performed S/FLG-OH cathode was used to fabricate the Coin Cell. The fabricated Coin Cell with S/FLG-OH as the cathode shows a stable potential over 50 cycles.

In Situ Characterization of Metastable Pb3O5 and Pb2O3 Phases During Thermal Decomposition of PbO2 to PbO.

Nonstoichiometric lead oxides play a key role in the formation and cycling of the positive electrodes in a lead acid battery. These phases have been linked to the underutilization of the positive active material but also play a key role in the battery's cycle life, providing interparticle adhesion and the connection to the underlying lead grid. Similar phases have previously been identified by mass loss or color change during thermal annealing of PbO2 to PbO, suggesting that at least two intermediate PbOx phases exist. Using multiple, in situ analysis techniques (powder diffraction, X-ray absorption, X-ray photoelectron spectroscopy) and ex situ nuclear magnetic resonance measurements, the structural conversion and changes in the lead oxidation state were identified during this process. Isolation of the PbOx phases enabled confirmation of Pb3O5 and Pb2O3 by diffraction and the first 207Pb NMR measurement of these intermediates. The thermodynamic and kinetic stability of these intermediates and other reported polymorphs were determined by density functional theory, providing key insight into their origins and variation of PbOx structures found in previous studies.

The Possible Mechanism of Improving the Performance of Lead‐Acid Batteries by Using Aluminum Ions to Influence the Gel Structure

Gel lead‐acid batteries have the advantages of no acid leakage, no maintenance, and a long cycle life. In this article, it was found that Al3+ in the gel electrolyte can shorten the gel time and improve the stability of the gel. The battery test results show that the HRPSoC cycle life of the gel battery can be significantly improved by adding Al3+. In comparison to blank gel batteries without Al3+, HRPSoC cycle life is 8.2 times higher. Additionally, the gel battery with added Al3+ has a 0.5C discharge capacity of 1.8 Ah, which is 2.5 times that of the blank gel battery. The added Al3+ also demonstrates good capacity stability and still retains a capacity of 1.7 Ah after 150 discharge cycles. The kinetic simulation shows that Al3+ may participate in the formation of a silicon gel system and tend to gather around Si atoms to affect the properties of the gel electrolyte.

Improving Zn2+ migration via designing multiple zincophilic polymer electrolyte for advanced aqueous zinc ion batteries

Aqueous zinc ion batteries (AZIBs)-based on Zn metal anode face serious issues of hydrogen evolution, corrosion, and zinc dendrite growth, limiting their practical applications. Polymer-based electrolytes can effectively inhibit the above issue, but usually bring additional interfacial resistance, resulting in slow reaction kinetics. Herein, we report a poly(4-acryloylmorpholine) electrolyte with multiple zincophilic primitives for fast zinc ion transport at bulk and interface of Zn metal anode (zinc ion transfer number of 0.77) via a facile one-pot polymerization. The special electrolyte structure with multiple zincophilic primitives can adhere tightly to the Zn metal anode and induce uniform Zn deposition, resulting in low interface resistance and enhanced cycling life of batteries. Therefore, the symmetric Zn||Zn batteries assembled based on the designed and synthesized polymer electrolyte can be stably cycled for 1400 with low overpotential (∼220 mV) at 0.5 mA cm−2 with a capacity of 0.5 mAh cm−2, and the corresponding V2O5||Zn full batteries exhibit attractive reversibility, rate performance, and cycling stability. The electrolyte engineering in this work paves a new path for the construction of polymer-based electrolytes for safe and stable AZIBs.

Regulating ion transport in lithium metal batteries via metal‐organic frameworks electrolyte modulator

AbstractLow Li+ transference number in liquid electrolytes can lead to uneven lithium deposition and dendrite growth, reducing coulombic efficiency and cycle life of lithium metal batteries. In this study, metal‐organic frameworks (MOFs) are used as electrolyte modulator to regulate Li+ transport. The ‐NH2 group introduced into MOFs can form hydrogen bonds with anions in the electrolyte, immobilizing these anions and thereby facilitating the migration of cations. As a result, a uniform and dense deposition morphology of lithium was achieved. The Li+ transference number is increased from 0.26 to 0.57. The assembled Li||Li symmetrical cell can stably cycle for over for 900 h with an average overpotential below 20 mV. In addition, the rate performance of the battery can be enhanced.

Densification of Alloying Anodes for High Energy Lithium-Ion Batteries: Critical Perspective on Inter- Versus Intra-Particle Porosity.

High Li-storage-capacity particles such as alloying-based anodes (Si, Sn, Ge, etc.) are core components for next-generation Li-ion batteries (LIBs) but are crippled by their intrinsic volume expansion issues. While pore pre-plantation represents a mainstream solution, seldom do this strategy fully satisfy the requirements in practical LIBs. One prominent issue is that porous particles reduce electrode density and negate volumetric performance (WhL-1) despite aggressive electrode densification strategies. Moreover, the additional liquid electrolyte dosage resulting from porosity increase is rarely noticed, which has a significant negative impact on cell gravimetric energy density (Whkg-1). Here, the concept of judicious porosity control is introduced to recalibrate existing particle design principles in order to concurrently boost gravimetric and volumetric performance, while also maintaining the battery's cycle life. The critical is emphasized but often neglected role that intraparticle pores play in dictating battery performance, and also highlight the superiority of closed pores over the open pores that are more commonly referred to in the literature. While the analysis and case studies focus on silicon-carbon composites, the overall conclusions apply to the broad class of alloying anode chemistries.

Solid-state polymer-particle hybrid electrolytes: Structure and electrochemical properties.

Solid-state electrolytes (SSEs) are challenged by complex interfacial chemistry and poor ion transport through the interfaces they form with battery electrodes. Here, we investigate a class of SSE composed of micrometer-sized lithium oxide (Li2O) particles dispersed in a polymerizable 1,3-dioxolane (DOL) liquid. Ring-opening polymerization (ROP) of the DOL by Lewis acid salts inside a battery cell produces polymer-inorganic hybrid electrolytes with gradient properties on both the particle and battery cell length scales. These electrolytes sustain stable charge-discharge behavior in Li||NCM811 and anode-free Cu||NCM811 electrochemical cells. On the particle length scale, Li2O retards ROP, facilitating efficient ion transport in a fluid-like region near the particle surface. On battery cell length scales, gravity-assisted settling creates physical and electrochemical gradients in the hybrid electrolytes. By means of electrochemical and spectroscopic analyses, we find that Li2O particles participate in a reversible redox reaction that increases the effective CE in anode-free cells to values approaching 100%, enhancing battery cycle life.

Rapidly Prepared Lithophilic Frameworks Stabilizes Lithium Anodes via Altered Lithium Deposition Patterns.

Lithium metal batteries are regarded as promising candidates for next-generation energy storage systems. However, their anodes are susceptible to interfacial instability due to significant volume changes, which significantly impacts the cycle life of lithium metal batteries. Here, a rapid method for the fabrication of 3D-hosts with interface modified layers is reported. A simple infiltration and heating process enables the transformation of copper foam into Zn-BDC-modified copper foam within 1 min, rendering it suitable for use as a current collector for lithium metal anodes. The Zn-BDC nanosheets with high lithiophilicity are uniformly distributed on the surface of the current collector, facilitating the uniform deposition of lithium and reducing the volume change. Consequently, the half cell exhibits a remarkably low overpotential (26mV) at a current-density of 4mA cm-2 and is cycled stably for 1000h. Furthermore, it demonstrates a significant enhancement in performance in the LiFePO4 full cell. This study provides a crucial reference on the connection between the interfacial modification of the current collector and the lithium deposition behavior, which promotes the practicalization of lithium metal anodes.

Attention Mechanism-Based Neural Network for Prediction of Battery Cycle Life in the Presence of Missing Data

As batteries become widespread applications across various domains, the prediction of battery cycle life has attracted increasing attention. However, the intricate internal mechanisms of batteries pose challenges to achieving accurate battery lifetime prediction, and the inherent patterns within temporal data from battery experiments are often elusive. Meanwhile, the commonality of missing data in real-world battery usage further complicates accurate lifetime prediction. To address these issues, this article develops a self-attention-based neural network (NN) to precisely forecast battery cycle life, leveraging an attention mechanism that proficiently manages time-series data without the need for recurrent frameworks and adeptly handles the data-missing scenarios. Furthermore, a two-stage training approach is adopted, where certain network hyperparameters are fine-tuned in a sequential manner to enhance training efficacy. The results show that the proposed self-attention-based NN approach not only achieves superior predictive precision compared with the benchmarks including Elastic Net and CNN-LSTM but also maintains resilience against missing-data scenarios, ensuring reliable battery lifetime predictions. This work highlights the superior performance of utilizing attention mechanism for battery cycle life prognostics.

Design of Ultrathin Asymmetric Composite Electrolytes for Interfacial Stable Solid-State Lithium-Metal Batteries.

Ultrathin composite electrolytes hold great promise for high energy density solid-state lithium metal batteries (SSLMBs). However, finding an electrolyte that can simultaneously balance the interfacial stability of the lithium anode and high-voltage cathode is challenging. The present study utilized the both-side tape casting technique to fabricate ultrathin asymmetric composite electrolytes reinforced with polyimide (PI) fiber membrane, with a thickness of 26.8 μm. The implementation of this asymmetric structural design enables SSLMBs to attain favorable interfacial characteristics, such as exceptional resistance to lithium dendrite puncture and compatibility with high voltages. The suppression of lithium dendrite growth and the extension of the cycle life of lithium symmetric batteries by 4000 h are both experimental and theoretically demonstrated under the dual confinement of PI fiber membrane and Li7La3Zr2O12 ceramic fibers. Furthermore, the integration of multicomponent solid electrolyte interphase and cathode electrolyte interface interfacial layers into the lithium anode and high-voltage cathode enhance theirs cycling stability. With a gravimetric/volumetric energy density of 333.1 Wh kg-1/713.2 Wh L-1, the assembled LiNi0.8Co0.1Mn0.1O2 pouch cell demonstrates exceptional safety. The extensive application of this design concept to SSLMBs enables the resolution of electrode/electrolyte interface issues.

Improving lithium deposition in porous electrodes: Phase field simulation

The development of structured lithium metal anodes is a key area of focus in the field of lithium battery research, which can significantly improve the energy density, cycle life and safety of lithium metal batteries. In this study, an electrochemical phase field model is used to construct the total free energy of the electrochemical system in conjunction with the effect of the porous electrode scaffold. It investigates the anisotropy of the diffusion coefficient of lithium ions in the electrolyte and the effect of the gradient size of the porous electrode scaffolds on the lithium deposition within the pores. Our numerical results show that increasing the diffusion coefficient of lithium ions in the x-direction cannot improve the lithium deposition within the pores. Instead, it leads to the appearance of lithium dendrites in the top layer of the porous electrode. Appropriately increasing the diffusion coefficient of lithium ions in the y-direction can significantly increase the lithium deposition capacity within the pores. However, excessive increases can lead to a reversal of the lithium deposition capacity within the pores. In addition, adopting the gradient size of the porous electrode scaffold in the y-direction can effectively alleviate the phenomenon that lithium metal is preferentially deposited at the top of the scaffold. These findings provide new ideas for the future design of structured lithium metal anode batteries.

Enhancing interfacial kinetics and stability of LiMn2O4 cathode by fabricating an artificial cathode electrolyte interphase of LiNbO3

LiMn2O4 (LMO) cathode material has received continuous attention due to its low price, environmental friendliness, high voltage platform, and high safety. However, the structure distortion is usually caused by the Jahn-Teller effect of Mn3+ in LMO, in which Mn3+ undergoes disproportionation reaction, resulting in the dissolution of Mn element and leading to the problems of fast capacity decay and short cycle life of battery. In this study, a thin (∼3 nm) artificial cathode electrolyte interphase (CEI) of LiNbO3 (LNO) is uniformly covered on the surface of LMO powder (LMO@LNO) by magnetron sputtering method. Compared with the bare LMO, LMO@LNO delivers a higher discharge capacity and better cycling stability. The capacity retention rate of bare LMO/Li cell reaches 80 % in 150 cycles, while LMO@LNO/Li cell can cycle up to 700 cycles, greatly prolonging the cycle life of battery. According to the experimental tests, it is found that the CEI layer of LNO not only improves the interfacial kinetics of electrode, but also inhibits the dissolution of Mn element and side reactions between electrolyte and electrode, thus effectively enhances the rate capability and cycling stability of batteries even at 55 °C and high-voltage of 4.8 V.

Onboard in-situ warning and detection of Li plating for fast-charging batteries with deep learning

Accurate lithium plating detection and warning are essential for developing safer, longer cycle life, and faster charging batteries. However, it is difficult to in-situ detect lithium plating from the electrochemical signals without the introduction of sensors or reference electrodes. Here, we proposed an online lithium plating detection and warning method based on anode potential construction. By establishing a precise mapping relationship between battery voltage and three-electrode potential through deep learning, we can reconstruct the three-electrode curve of batteries accurately without introducing a reference electrode. So that lithium plating can be detected over the full life cycle of batteries with a positive rate of 99.9%. Furthermore, with the combination of the voltage prediction module, the future anode potential can be predicted and the lithium plating can be warned with a positive rate of 98.7%. Our approach provides a new possibility for the development of fast-charging technology and life extension strategies.

Operation strategy and optimization configuration of hybrid energy storage system for enhancing cycle life

Hybrid energy storage system (HESS) can take advantage of complementarity between different types of storage devices, while complementary strategies applied to configuration or operation have a significant impact on the battery cycle life. Therefore, in order to enhance the battery cycle life, this paper proposes an operation strategy and configuration technique for HESS and verifies it by a scenario of HESS tracking scheduling plan. Firstly, a linear rainflow counting method, which can be embedded in the optimization process, is proposed to quantitatively evaluate the cycle life of energy storage based on the half cycle identification model. Secondly, an operation strategy with the integration of the constraint of state-of-charge (SOC) recovery capability considering the dynamic degradation of energy storage cycle life during operation is proposed to ensure a certain charging and discharging margin for storages, thereby enhancing the cycle life of HESS. Thirdly, an optimization configuration model considering the operation strategy of HESS is established based on the minimum annualized investment cost. And the linearization techniques are used to transform the original problem into a mixed-integer linear programming problem, and the mathematical programming technique is adopted to solve the problem. Finally, the effectiveness of the proposed method is validated through case studies. The results of the case studies show that the use of the HESS operation strategy proposed in this paper can manage the VRB's SOC more efficiently, and the control effect of VRB's SOC is improved by 71.5 %. Meanwhile, by controlling the VRB's SOC, the cycle life of the energy storage in the HESS can be effectively improved, which reduces the annualized cost of the HESS by 53 %.

Enhancing performance and longevity of solid-state zinc-iodine batteries with fluorine-rich solid electrolyte interphase

Rechargeable zinc-iodine (ZnI2) batteries have gained popularity within the realm of aqueous batteries due to their inherent advantages, including natural abundance, intrinsic safety, and high theoretical capacity. However, challenges persist in their practical applications, notably battery swelling and vulnerability in aqueous electrolytes, primarily linked to the hydrogen evolution reaction and zinc dendrite growth. To address these challenges, this study presents an innovative approach by designing a solid-state ZnI2 battery featuring a solid perfluoropolyether based polymer electrolyte. The results demonstrate the formation of a solid electrolyte interphase layer on zinc, promoting horizontal zinc growth, mitigating dendrite penetration, and enhancing battery cycle life. Moreover, the solid electrolyte hinders the iodine ion shuttle effect, reducing zinc foil corrosion. Symmetric batteries employing this electrolyte demonstrate excellent cycle performance, maintaining stability for approximately 5000 h at room temperature, while solid-state ZnI2 batteries exhibit over 7000 cycles with a capacity retention exceeding 72.2%. This work offers a promising pathway to achieving reliable energy storage in solid-state ZnI2 batteries and introduces innovative concepts for flexible and wearable zinc batteries.

Ionic Liquids as Cathode Additives for High Voltage Lithium Batteries

AbstractTwo oxalatoborate ionic liquids (ILs), which are commonly utilized as electrolyte additives that form a protective layer on the cathode surface, are investigated for the first time as electrode additives. Cathodes based on LiNi0.5Mn1.5O4 (LNMO) containing 3 wt % ILs, i. e., “IL‐enriched cathodes”, exhibit capacity values above 120 mAh/g with high Coulombic efficiencies throughout cycling over 200 times. A cathode without ILs also exhibits a capacity of 119 mAh/g but its Coulombic efficiency becomes low and unstable after 109 cycles. In addition, when 0.3 M ILs are added to conventional carbonate‐based electrolytes, the battery cycle life improves but there is a reduction in the capacity probably due to low ionic conductivity of the electrolyte mixtures. Post‐mortem analyses of electrodes retrieved from cycled cells highlight less electrolyte decomposition and less cathode corrosion, enabled by using the IL as the additive in LNMO, which are confirmed by a particle shape with smooth surface identical to the fresh cathode. The study demonstrates that oxalatoborate ILs can be used as the electrode additive, and this provides a new concept for cathode formulations for high performance batteries with a small amount of ILs.

Modeling spatiotemporal temperature dynamics of large-format power batteries: A multi-source information fusion approach

Uneven temperature distributions can significantly impact battery performance and cycle life. Industrial applications, in particular, where unknown disturbances and limited sensors exist, pose significant challenges for accurately estimating the battery temperature field. This work proposes a multi-source information fusion framework for capturing the spatiotemporal temperature dynamics of pouch-type Lithium-ion batteries. First, we develop a system model of the battery thermal process based on physical insights, considering unknown parameter deviations and unmodeled dynamics. Next, we use the Galerkin-spectral method to expand the spatiotemporal variable and reduce the original infinite-dimensional system to a low-order model containing the most important system modes. The unknown component of the model is then entirely stripped and integrated into a nonlinear term. To close the reality gap of the physics-based model, we subsequently develop an error compensation model that learns the dynamic behavior from sparse observations. Ultimately, our framework design yields a fusion-driven model for reliable temperature field prediction. Simulations and experimental data validate the superior performance and generalization capability of the proposed method.

Analysis of the Ecological Footprint from the Extraction and Processing of Materials in the LCA Phase of Lithium-Ion Batteries

The development of batteries used in electric vehicles towards sustainable development poses challenges to designers and manufacturers. Although there has been research on the analysis of the environmental impact of batteries during their life cycle (LCA), there is still a lack of comparative analyses focusing on the first phase, i.e., the extraction and processing of materials. Therefore, the purpose of this research was to perform a detailed comparative analysis of popular electric vehicle batteries. The research method was based on the analysis of environmental burdens regarding the ecological footprint of the extraction and processing of materials in the life cycle of batteries for electric vehicles. Popular batteries were analyzed: lithium-ion (Li-Ion), lithium iron phosphate (LiFePO4), and three-component lithium nickel cobalt manganese (NCM). The ecological footprint criteria were carbon dioxide emissions, land use (including modernization and land development) and nuclear energy emissions. This research was based on data from the GREET model and data from the Ecoinvent database in the OpenLCA programme. The results of the analysis showed that considering the environmental loads for the ecological footprint, the most advantageous from the environmental point of view in the extraction and processing of materials turned out to be a lithium iron phosphate battery. At the same time, key environmental loads occurring in the first phase of the LCA of these batteries were identified, e.g., the production of electricity using hard coal, the production of quicklime, the enrichment of phosphate rocks (wet), the production of phosphoric acid, and the uranium mine operation process. To reduce these environmental burdens, improvement actions are proposed, resulting from a synthesized review of the literature. The results of the analysis may be useful in the design stages of new batteries for electric vehicles and may constitute the basis for undertaking pro-environmental improvement actions toward the sustainable development of batteries already present on the market.