Cylindrical Lithium-ion Battery Research Articles

Quantitative measurement of thermal performance of a cylindrical lithium-ion battery

Measuring the thermal performance of lithium-ion battery cells is a critical task in the thermal design of electric vehicle battery packs. This study introduces a quantitative method to assess the thermal performance of cylindrical 21,700 cells considering heat loss, under conditions of both high and low temperature-rises. By supervising the cell’s outgoing heat-flux (heat loss), we thoroughly analyzed the differences in cell heat generation rates between high temperature-rise (HTR) and low temperature-rise (LTR) conditions. The results show that under LTR conditions, the cell heat generation exhibits a “fast-slow-fast” increasing trend, while under HTR conditions, it displays a U-shaped pattern. Notably, the mean cell heat generation rate increases with decreasing temperatures and increasing discharge rates, especially under LTR conditions, where it significantly outperforms that under HTR conditions. This method provides valuable insights for optimizing the thermal design of battery packs.

Advanced Thermal Management of Cylindrical Lithium-Ion Battery Packs in Electric Vehicles: A Comparative CFD Study of Vertical, Horizontal, and Optimised Liquid Cooling Designs

Advanced Thermal Management of Cylindrical Lithium-Ion Battery Packs in Electric Vehicles: A Comparative CFD Study of Vertical, Horizontal, and Optimised Liquid Cooling Designs

Finite Element Analysis of the Mechanical Response for Cylindrical Lithium-Ion Batteries with the Double-Layer Windings

The plastic properties for the jellyroll of lithium-ion batteries showed different behavior in tension and compression, showing the yield strength in compression being several times higher than in tension. The crushable foam models were widely used to predict the mechanical responses to compressive loadings. However, since the compressive characteristic is dominant in this model, it is difficult to identify distributions of the yield strength in tension. In this study, a simplified jellyroll model consisting of double-layer windings was devised to reflect different plastic characteristics of a jellyroll, and the proposed model was applied to an 18650 cylindrical battery under compressive loading conditions. One winding adopted the crushable foam model for representing the compressive plastic behavior, and the other winding adopted the elastoplastic models for tracking the tensile plastic behavior. The material parameters in the crushable foam model were calibrated by comparing the simulated force–displacement curve with the experimental one for the case where the cell was crushed between two plates when the punch was displaced by 7 mm. A specific cut-off value (10 MPa) was assigned to a yield stress limit in the elastoplastic model. Further, the computational model was validated with two more loading cases, a cylindrical rod indentation and a spherical punch indentation, as the punch was displaced by 6.3 mm and 6.5 mm, respectively. For three loading cases, deformed configurations and plastic strain distributions were investigated by finite element analysis. It was found that the proposed model clearly provides the plastic behavior both in compression and tension. For the crush simulation, the maximum compressive stress approached 222 MPa in the middle of the jellyroll, and the maximum effective plastic strain approached 60% in the middle of the layered roll. For indentation with the cylindrical and the spherical punch, the maximum effective plastic strain approached 52% and 277% in the layered roll, respectively. The local crack or location of a short circuit could be predicted from the maximum effective plastic strain.

Investigating Anode Potential Errors of Real-Time Capable DFN Type Models Induced by Inhomogeneity for Fast Charging of Cylindrical Lithium-Ion Batteries

The occurrence of lithium plating during fast charging poses a safety risk and can reduce the battery lifespan. To prevent plating during the application of model-based charging protocols, a safety margin is added to the lithium plating voltage criterion to compensate for unaccounted in-plane heterogeneities. This article investigates the value of this safety buffer when using real-time capable 1D-DFNs coupled with a 0D thermal model. Through comparison with a multi-scale model, the 1D-DFN error to the local minimum in the anode potential can be characterized. An adjusted cooling coefficient enables 0D temperature modeling with an average error of less than 1 ◦C, despite the inability to consider temperature gradients. For a high-energy NMC811/SiC parameterization of a 4680 format cell with tabless current collectors, the 1D-DFN error in the anode potential deviates by a maximum of 10 mV during charging up to 3C at 50 W m−2 K−1 convective mantle cooling. The anode potential error is influenced by the charging rate, cooling strategy, cell format, and current collector design.

Experimental exploration of nano-phase change material composites for thermal management in Lithium-ion batteries

The present study reports an experimental investigation carried out for the thermal management of cylindrical lithium-ion battery simulator using aluminium oxide (nano particle)-eicosane (phase change material) composites. The experiment involves varying the power input from 4 to 10 W in 2 W increments and adjusting the weight percentage of nanoparticles (wt %) from 0.5 to 0.9 in 0.2 wt % intervals. The examination of battery temperature evolutions in response to heating power, a comprehensive heat transfer analysis incorporating Nusselt number, determination of maximum temperature difference, thermal resistance analysis, and exploration of temperature variations in the absence of Phase Change Material (PCM) are considered. The results show that increase in weight percentage of alumina nanoparticles in phase change material cannot always improve the thermal performance. The results of the present study give a guideline for designing battery thermal management system. The power levels used in the experiment vary from 4 W to 10 W in steps of 2 W. For a power level of 4 W, the heat flux is 1.088 kW/m2, and for a power level of 10 W, the heat flux is 2.72 kW/m2.

Detection and Analysis of Abnormal High-Current Discharge of Cylindrical Lithium-Ion Battery Based on Acoustic Characteristics Research

The improvement of battery management systems (BMSs) requires the incorporation of advanced battery status detection technologies to facilitate early warnings of abnormal conditions. In this study, acoustic data from batteries under two discharge rates, 0.5 C and 3 C, were collected using a specially designed battery acoustic test system. By analyzing selected acoustic parameters in the time domain, the acoustic signals exhibited noticeable differences with the change in discharge current, highlighting the potential of acoustic signals for current anomaly detection. In the frequency domain analysis, distinct variations in the frequency domain parameters of the acoustic response signal were observed at different discharge currents. The identification of acoustic characteristic parameters demonstrates a robust capability to detect short-term high-current discharges, which reflects the sensitivity of the battery’s internal structure to varying operational stresses. Acoustic emission (AE) technology, coupled with electrode measurements, effectively tracks unusually high discharge currents. The acoustic signals show a clear correlation with discharge currents, indicating that selecting key acoustic parameters can reveal the battery structure’s response to high currents. This approach could serve as a crucial diagnostic tool for identifying battery abnormalities.

Dynamic responses of cylindrical lithium-ion battery under localized impact loading

Engineering problems, such as fire and explosion caused by mechanical damage, have restricted the further development of lithium-ion batteries (LIBs). The paper aims to present an effective method for studying the impact responses of cylindrical LIBs under localized impact loadings. An impact model in which the cell is simplified to a beam is developed considering the interaction between bending and stretching. The membrane factor (fn ) of the beam with a circular cross-section is introduced, and then the motion control equations for the cell with large deformation are derived. The accuracy of the theoretical method is verified based on the results from the mass block impact experiment and finite element simulation. A method for cell failure detection is established based on the force-displacement-voltage response from the impact experiment. It is shown that higher impact velocities and smaller punch widths increase cell deformation. Moreover, a larger punch mass results in greater displacement when the impact energy remains unchanged, and the strengthening tendency increases with the punch width. The research will provide theoretical guidance for the safety assessment and dynamic optimization design of LIBs.

Expression of Concern for article entitled “Investigation of the use of extended surfaces in paraffin wax phase change material in thermal management of a cylindrical lithium-ion battery: Applicable in the aerospace industry”

Expression of Concern for article entitled “Investigation of the use of extended surfaces in paraffin wax phase change material in thermal management of a cylindrical lithium-ion battery: Applicable in the aerospace industry”

Editor's Note for article entitled “An online temperature estimation for cylindrical lithium-ion batteries based on simplified distribution electrical-thermal model”

Editor's Note for article entitled “An online temperature estimation for cylindrical lithium-ion batteries based on simplified distribution electrical-thermal model”

A novel thermal management system for a cylindrical battery based on tubular thermoelectric generator

This study introduces an innovative thermal management system tailored for cylindrical Lithium-ion batteries. It integrates a tubular thermoelectric generator (TTEG) to handle both battery thermal management and the utilization of waste heat for power generation. The main focus lies in evaluating the waste heat recovery capabilities of the TTEG to enhance effective thermal management. The research investigates key geometric and operational parameters such as battery discharge rate (C-rate), thermocouple count (NTC), heat transfer coefficient (HTC), and thermoelectric leg height (HL) to comprehensively assess the overall system performance. The results highlight that integrating the TTEG improves thermal management and waste heat recovery in lithium-ion batteries. It demonstrates temperature reductions of up to 21 °C at a discharge rate of 3C compared to batteries without the TTEG thermal management system. Additionally, increasing the NTC leads to a rise in the maximum battery temperature, thereby enhancing waste heat recovery performance. For instance, increasing the number of thermocouples from 100 to 144 results in a substantial up to 70 % increase in TTEG voltage.Furthermore, enhancing HTC and HL positively impacts thermal performance, showing a significant decrease in the maximum battery temperature. Elevated HTC and HL also contribute to improving thermoelectric voltage, power, and conversion efficiency, highlighting their dual role in enhancing waste heat recovery. For instance, at peak conditions, there is a notable reduction of 2.66 °C in the maximum battery temperature with an HL of 12 mm compared to 4 mm. Additionally, increasing HTC from 10 to 20, particularly at maximum discharge, leads to a surge of 15.87 % in voltage and a substantial 34.28 % increase in output power.

Analysis of melting behavior of layered different phase change materials for a cylinder insert into a channel

Phase change materials (PCMs) have diverse fields of application due to higher thermal inertia. The present study explores the melting behavior in dual-layered different PCMs in a cylindrical lithium-ion battery module placed in a long channel under the hot air stream. The main cylinder is packed with paraffin wax and covered PCM is chosen as calcium chloridehexahydrate (CaCl2-6H2O). The material between two PCMs is considered highly conductive and impermeable. The involved mathematical equations in two-dimensional forms are numerically simulated the applying the finite volume technique. The primary important parameters of melting behavior are the difference in temperature and inlet air velocity. The analysis is carried out for the effective parameters such as the inlet air temperature (Thot = 100 °C and 120 °C) and air velocity (սair = 2.5 and 5.0 m/s). The results revealed that an increase in air velocity reduces the highest and average temperature of the PCM. The changes in melting time of PCMs decline with time. Higher inlet air temperature also causes fast melting of the PCMs over time. The analysis revealed that the application of PCMs is undue when there is no phase change process. The analysis also revealed that an increment in the inlet air velocity causes a decrease in the average temperature. For the same air inlet temperature (Thot) higher air velocity leads to a slower rate of the melting process Therefore, melting time is less by ∼ 30 % (for the inner layer) and 32 % (for the outer layer) with decreasing air velocity. The findings of this study will help the designer to improve the battery thermal management system by modulating the temperature.

Numerical study on hybrid battery thermal management system integrating water, phase change material, and fins, under New European Driving Cycle

This study introduced a hybrid thermal management system for a 4×4 cylindrical lithium-ion battery module, simulating New European Driving Cycle (NEDC) conditions. The system integrated water, phase change material (PCM), and fins for enhanced heat dissipation. The batteries, attached to an aluminium shell, incorporated PCM and a central coolant path. Fins were introduced between the coolant channel and Al shell to enhance heat transfer between batteries, PCM, and water. Comparative analysis against passive (PCM only) and active (liquid) cooling systems revealed the hybrid system’s superior performance. With a water flow rate of 2×10−8 m3/s, the system consistently kept temperatures below 50°C during charge-discharge cycles. Compared to active cooling, it achieved a significant temperature reduction of 18.47% and 5.01% after the charge and discharge processes. An intermittent cooling strategy further demonstrated its effectiveness in preventing thermal runaway (> 60°C) compared to the active cooling system. The proposed hybrid system demonstrated efficient thermal performance with low pumping power, suggesting its potential for multiple charge/discharge cycles.

Experimental study on the internal short circuit and failure mechanism of lithium-ion batteries under mechanical abuse conditions

The safety issues of lithium-ion batteries under mechanical abuse conditions have attracted widespread attention due to their high uncertainty and risk. This research takes cylindrical lithium-ion batteries as the research object and conducts three-point bending tests on cylindrical lithium-ion batteries with different states of charge (SOC), electrode thicknesses and electrode materials. The mechanical response, voltage changes, temperature changes during the loading process of the battery, and the microstructural changes of the battery's electrodes and separator after the bending test were examined. The results show that the maximum load-bearing capacity of the battery and the displacement corresponding to the short circuit decreases with the SOC of battery; the higher the battery SOC means a faster average temperature rise rate of the battery. When the SOC is higher than 60 %, the battery will experience violent thermal runaway phenomena such as explosions and spouting fire after bending tests. The mass loss rate of the battery is also greatly affected by the battery SOC and the electrode thickness, however, electrode material have almost no effect on the mass loss rate of the battery. According to the SEM images of the electrodes, it is found that short circuits cause graphite particles to break, separators to close and electrolytes oxidize on the surface of positive electrode particles. After triggering the internal short circuit, more broken particles are observed in the positive electrode material of the battery with thicker electrodes and the surface roughness of the broken particles is higher. By comparing the electrode changes of LFP and NCM, it is found that the intensity of the internal electrochemical reactions in NCM is far greater than that in LFP. The research results provide theoretical insights for understanding the electrothermal characteristics and mechanical integrity of lithium-ion batteries under mechanical abuse, which can shed light on the design and optimization of high-performance and safe lithium-ion batteries.

Complex reaction mechanisms of electrolyte decomposition at large-scale Ni-rich Li-ion battery cells including electrode crosstalk effect

Ni-rich cathodes are essential for the advancement of high-energy lithium-ion batteries but encounter significant challenges at elevated voltages, including oxygen liberation and enhanced surface reactivity, which precipitate electrolyte decomposition. This study explores the intricate reaction mechanisms of electrolyte decomposition linked to the pronounced release of oxygen from the cathode lattice in large-scale 18650 cylindrical cells employing Ni-rich LiNi0.90Mn0.05Co0.05O2(NMC90)//graphite configurations, focusing on electrode crosstalk effects at high voltages. Notably, acetals such as methoxy methanol (49.93 %) and methane diol (50.07 %) were identified at 4.7 V, with their presence escalating at 4.9 V. Formaldehyde, present at 7.21 %, along with methanol (22.77 %), methane diol (36.35 %), and methoxy methanol (33.67 %), begins to manifest at 4.9 V. The dissolution of transition metals was analyzed using Inductively Coupled Plasma Atomic Emission Spectrometry, and changes in the double-layer capacitance were assessed through electrochemical impedance spectroscopy, further validating the link between these decomposition products and cathode failure associated with oxygen release. These insights reveal the complex relationship between electrolyte decomposition and cathode degradation due to oxygen release, highlighting a critical failure mechanism in large-scale cylindrical lithium-ion batteries.

Influence of Cylindrical Cells Surface Cleaning by Means of Laser Ablation on Wedge Wire Bonding Process

Wire bonding is a method of connecting two or more surfaces by the means of a thin wire which is ultrasonically bonded to those surfaces and provides an electrical connection. While this method is well established in the microelectronics industry its popularity is rising in the area of cylindrical lithium-ion battery pack manufacturing. Previous studies have shown that even in experimental conditions this process might be unstable which was indicated by the high standard deviation of the bonds shear test results. This might have been related to contamination of the interface area between the joined materials. The aim of this study was to determine the impact of surface laser cleaning on the properties of the wire-bonded joint. The results have shown that laser cleaning with 40% power of the 30 W ATMS4060 laser marker helps to reduce the standard deviation of the shear test results from 16.1% for the uncleaned sample down to 2.6% and greatly reduces the number of oxides within the interface area of the bond cross section. Cleaning with 80% of the laser power did not have a further impact on shear test results and almost completely eliminated oxides from the bonded materials interface.

Laser-induced thermal runaway dynamics of cylindrical lithium-ion battery

Laser is a precise, remote, and non-invasive heating method that can initiate thermal runaway of lithium-ion batteries in safety tests. This study systemically explores the thermal runaway of cylindrical cells induced by constant laser irradiation up to 20 W and 1.6 MW m−2 within a 4-mm diameter spot. Results indicate that thermal runaway intensity is relatively insensitive to the laser power but controlled by the battery state of charge (SOC). The overall heating efficiency of the laser (78 ± 7 %) is higher than that of the oven and comparable to contact heating methods. As the battery SOC decreases from 100 % to 30 %, the minimum laser output power for thermal runaway increases from 9.5 W to 15 W, corresponding to the effective battery heating power rising from 6.7 W to 11.1 W. These critical values hold significance in evaluating the thermal hazards associated with localized hotspot failures. Finally, the strategy for applying the laser to trigger the battery thermal runaway is proposed based on a simplified heat transfer model. This work reveals the battery fire risk under high-intensity spot heating and provides a valuable scientific basis for using laser heating in battery safety test standards.

Electrolyte Leakage in Cylindrical Lithium-Ion Batteries Subjected to Temperature Cycling

In transportation and operation, lithium-ion batteries can be exposed to environments where the temperature exceeds 75 °C, compromising seal integrity and leading to electrolyte leakage and safety issues. Standards introduced by regulatory bodies require temperature testing, including temperature cycling tests. This study examines cylindrical battery electrolyte leakage due to temperature cycling between 25 °C and 80 °C through capacity tests, electrochemical impedance spectroscopy, computed tomography scans, and thermal analysis. Different thermal expansions among battery cap elements were identified as the cause of leakage. The thermal test parameters and requirements in the UN Manual of Tests and Criteria Section 38.3 were reviewed, revealing the 72 °C upper-temperature limit and the 24 h storage period after temperature cycling fail to effectively qualify lithium-ion batteries for real-world applications.

Calibration of Crushable Foam Models for the Jellyroll of Cylindrical Lithium-Ion Batteries

Crushable foam plasticity models are employed to simulate material response under essentially monotonic loading. For the plastic part of the behavior, the default crushable foam model in Abaqus/Explicit is the volumetric hardening model, where the yield surface evolves by the volumetric compacting plastic strain, and the other available model is the isotropic hardening model, where the yield curve is centrally located at the origin in the pressure—the Mises stress plane. In this study, the characteristic of two models was examined by applying them to a simple 18650 lithium-ion cylindrical cell. The computation cell model consists of the shell casing and the homogenized jelly roll which represents the electrode assembly. Both crushable foam models were calibrated to represent the homogenized mechanical properties of the jellyroll, and the load–displacement relations were compared with the experimental results. Then, we examined the deformation characteristic of jellyroll for each crushable foam model.

Numerical heat generation analysis of the tabbed and novel tabless designs of cylindrical-type lithium-ion batteries

The heat generation behaviours of a traditional tabbed cylindrical lithium-ion (Li-ion) battery are known to greatly affect its performance, cycle life, and safety. In this study, we explore the heat generation behaviours of the tabbed and novel tabless designs of a 21,700 cylindrical cell with graphite anode and NCA/LiNi0.8Co0.15Al0.05O2 cathode, by coupling the discreet layers of a three-dimensional (3D) disassembled electrochemical (EC) model with a two-dimensional (2D) axisymmetric heat transfer (HT) model. The respective heat generation mechanisms of each battery components of tabbed and tabless designs are first compared, and it is observed that the tabbed design generates significantly more heat than the tabless design, with the negative current collectors (NCC) in the tabbed design accounting for over 80 % of the total heats at 1C-rate. Also, the tabless design reduces the cell voltage drop due to its lower ohmic impedance and promotes a more homogenous cell temperature than the tabbed design. Next, the effects of particle size (ω) for the tabless design on the ohmic, reversible, and polarization heats of the battery’s electrodes are investigated at a high discharge rate of 10C, and the results show that polarisation heat decreases significantly in both electrodes as ω decreases. At the Negative Electrode (NE), the ohmic heating decreases initially as ω decreases because the battery is not drawing significant current. As the current drawn increases, Li-ion transport resistance also increases and at depth of discharge (DoD) = 36 %, a reverse in the trend is observed leading to an increase in Ohmic heating up to the end of life. In contrast, the ohmic heating at the Positive Electrode (PE) increases throughout the discharge process as ω decreases. For the reversible heat, the heat is negative in the NE side initially and fluctuates with ω towards the end of life (DOD = 88 %) when it changes from heat sink to heat source, whereas in the PE it remains unchanged for all ω throughout the discharge process. The resulting temperature drop is caused by the increase in the overall reversible heat sink effect in the NE side, as well as the weakened polarization heat in both electrodes. On the other hand, miniaturising the electrode thickness (η) causes a considerable decrease in ohmic heating in both electrodes resulting in larger temperature drops and elevated voltage curve. This study provides relevant insights in support of the development of battery thermal management systems (BTMS) for the tabbed and novel tabless batteries in a realistic environment.

Safety Analysis of Lithium-Ion Cylindrical Batteries Using Design and Process Failure Mode and Effect Analysis

Cylindrical lithium-ion batteries are widely used in consumer electronics, electric vehicles, and energy storage applications. However, safety risks due to thermal runaway-induced fire and explosions have prompted the need for safety analysis methodologies. Though cylindrical batteries often incorporate safety devices, the safety of the battery also depends on its design and manufacturing processes. This study conducts a design and process failure mode and effect analysis (DFMEA and PFMEA) for the design and manufacturing of cylindrical lithium-ion batteries, with a focus on battery safety.