Cylindrical Battery Research Articles

Thermal performance assessment for an array of cylindrical Lithium-Ion battery cells using an Air-Cooling system

Modern society depends on energy storage systems like Lithium-ion (Li-ion) batteries. Li-ion battery cells are delicate to changes in temperature. Extreme environmental conditions affect their life cycle and performance. Therefore, effective cell temperature management is a must for secure and dependable battery operation. Additionally, the high production costs of electric cars must be countered by the adaptability of the battery pack design for modern electric vehicles. As the chemical reactions generate more heat and raise the battery's temperature, it may cause the battery to explode and cause fires in the workplace. To address this issue, the present work attempts to numerically study a novel design of an efficient air-cooling system for improving the performance of lithium-ion batteries by reducing the operational temperatures under a different coolant flow rate. The main output of the presented study is the analysis of a novel design of an efficient air-cooling system for lithium-ion batteries. The study aims to reduce the operational temperatures of the batteries under different coolant flow rates to improve their performance and service life. The numerical simulations are carried out using a finite volume-based computing tool with the K-epsilon (k-ε) turbulence model. The analysis is performed for various pertinent parametric ranges, including the spacing between the batteries, Reynolds numbers, and average Nusselt numbers. The results indicate that increasing air inlet velocity (Re) substantially reduces the average air temperature of the cooling pack and temperature difference (ΔT) of the battery cells, and the cooling pack's average heat transfer rate (Nu) increases monotonically as the Re increases.

Design, Properties, and Manufacturing of Cylindrical Li-Ion Battery Cells—A Generic Overview

Battery cells are the main components of a battery system for electric vehicle batteries. Depending on the manufacturer, three different cell formats are used in the automotive sector (pouch, prismatic, and cylindrical). In the last 3 years, cylindrical cells have gained strong relevance and popularity among automotive manufacturers, mainly driven by innovative cell designs, such as the Tesla tabless design. This paper investigates 19 Li-ion cylindrical battery cells from four cell manufacturers in four formats (18650, 20700, 21700, and 4680). We aim to systematically capture the design features, such as tab design and quality parameters, such as manufacturing tolerances and generically describe cylindrical cells. We identified the basic designs and assigned example cells to them. In addition, we show a comprehensive definition of a tabless design considering the current and heat transport paths. Our findings show that the Tesla 4680 design is quasi-tabless. In addition, we found that 25% of the cathode and 30% of the anode are not notched, resulting in long electrical and thermal transport paths. Based on CT and post-mortem analyses, we show that jelly rolls can be approximated very well with the Archimedean spiral. Furthermore, we compare the gravimetric and volumetric energy density, the impedance, and the heating behavior at the surface and in the center of the jelly rolls. From the generic description, we present and discuss production processes focusing on format and design flexible manufacturing of jelly rolls.

Degradation analysis of 18650 cylindrical cell battery pack with immersion liquid cooling system. Part 1: Aging assessment at pack level

Degradation analysis of 18650 cylindrical cell battery pack with immersion liquid cooling system. Part 1: Aging assessment at pack level

Performance Analysis of an Innovative PCM-Based Internal Cooling Design for Cylindrical Lithium-Ion Battery Considering Compact Structure and Uniform Temperature

Performance Analysis of an Innovative PCM-Based Internal Cooling Design for Cylindrical Lithium-Ion Battery Considering Compact Structure and Uniform Temperature

A numerical study on the capacity improvement of cylindrical battery cooling systems using nano-enhanced phase change material and axisymmetric stepped fins

A numerical study on the capacity improvement of cylindrical battery cooling systems using nano-enhanced phase change material and axisymmetric stepped fins

Battery Explosion Detection System

Abstract: Technologies utilising lithium-ion batteries are essential in altering the economy and lowering reliance on fossil fuels. Electricity is being used in manufacturing, transportation, and services. in Europe Within a decade, according to the Commission, everything that can be electrified in Europe will be. To ensure the security of the functioning of battery-powered electronic devices and to direct users in adopting behaviours that can increase battery life and reusability, it is essential to be able to estimate the state of charge (SOC) accurately. In this study, we explore how machine learning models can forecast the state of charge (SOC) of cylindrical Li-Ion batteries while taking into account a range of cells and charge-discharge cycles

Assessment of Newly-Designed Hybrid Nanofluid-Cooled Micro-Channeled Thermal Management System for Li-Ion Battery

Abstract Maintaining both maximum temperature and temperature uniformity within the desirable limit is a crucial issue for high C-rating Li-ion batteries of electric vehicles, which can be achieved by the properly designed battery thermal management system (BTMS). In this research, three new designs of liquid-cooled micro-channeled BTMS are suggested for cylindrical batteries to address the issue of temperature variations and uneven temperature distribution. Using 3D numerical simulation, we investigate the impacts of volume flowrate and the usage of mono/hybrid nanofluids with varying concentrations on the thermal performance of the battery pack at a high C-rate by utilizing a two-phase mixture model. Effects on maximum temperature, temperature uniformity, pumping power, and heat transfer coefficient to pressure drop ratio are investigated. Results demonstrate that the effectiveness of heat transmission and temperature uniformity of the battery pack are positively impacted by an increase in nanoparticle concentration in nanofluid and volume flow rate. Even at high C-rates (5 C), the proposed design can effectively reduce both cell temperature and thermal gradient of the 21700-type cylindrical cell. Design 3 is the most favorable BTMS for Li-ion cylindrical battery in terms of both maximum temperature and temperature uniformity (maximum temperature of 304.72 K and temperature difference of 4.7 K).

Effect of mechanical vibration on phase change material based thermal management system for a cylindrical lithium-ion battery at high ambient temperature and high discharge rate

The performance and safety of lithium-ion batteries (LIB) in electric vehicles (EV) depend strongly on the operating temperature, so an effective battery thermal management system (BTMS) is essential. Battery thermal management (BTM) technology based on phase change material (PCM) is currently considered to be one of the most promising approaches. Electric vehicles are inevitably affected by vibration during operation, and many studies have shown that mechanical vibration can enhance natural convection heat transfer. The effect of mechanical vibration on the PCM-based battery thermal management module of a single cylindrical lithium-ion battery at high ambient temperature and high discharge rate is studied by numerical simulation for the first time in this paper. N-octadecane is selected as the PCM application in the cylindrical battery's periphery. The results show that: (1) mechanical vibration enhances the heat transfer of natural convection to limit the excessive temperature rise and improve temperature uniformity of the lithium-ion battery, and when the PCM is 12 mm, the mechanical vibration has the most significant impact on the PCM-based BTMS (2) when the vibration frequency is 10 Hz, the cooling effect of the battery thermal management module is the best, which is 28.05% lower than when there is no vibration. when the vibration frequency is 50 Hz, the temperature uniformity of the battery is the best, with a maximum temperature difference of 3.86 K. (3) when the vibration amplitude is 100 mm, the maximum temperature difference of the battery is 1.89 K, and the maximum temperature decreases by 27.74%. This study provides a new perspective for the thermal management system of lithium-ion batteries for electric vehicles.

Numerical analysis of cylindrical lithium-ion battery thermal management system based on bionic flow channel structure

To improve the thermal and flow performance of the battery thermal management system (BTMS), a heat exchanger with a bionic flow channel structure was designed and applied to a cylindrical lithium-ion battery module in this work. To accurately reflect the transient thermal behavior of the battery, a battery thermal model was obtained by experimentally collecting thermodynamic parameters. A computational fluid dynamics model of the BTMS was established. The influences of different bionic flow channel structure parameters on the thermal performance of the BTMS were investigated by a multi-factor optimization analysis. In addition, the thermal performance was also compared with that of a heat exchanger with a bionic honeycomb-like structure and a traditional helical structure. The results show that at the optimum structural parameters, the maximum temperature, maximum temperature difference, and pressure drop of the BTMS were calculated as 302.656 K, 3.726 K and 29.69 Pa respectively. For the same volume fraction and geometrical parameters, the heat exchangers with a spider web-like structure has better thermal and flow characteristics than honeycomb-like and traditional helical structures.

Stability theory for metal pad roll in cylindrical liquid metal batteries

When liquid metal batteries are charged or discharged, strong electrical currents are passing through the three liquid layers that we find in their interior. This may result in the metal pad roll instability that drives gravity waves on the interfaces between the layers. In this paper, we investigate theoretically metal pad roll instability in idealised cylindrical liquid metal batteries that were simulated previously by Weber et al. (Phys. Fluids, vol. 29, no. 5, 2017b, 054101) and Horstmann et al. (J. Fluid Mech., vol. 845, 2018, pp. 1–35). Near the instability threshold, we expect weakly destabilised gravity waves, and in this parameter regime, we can use perturbation methods to find explicit formulas for the growth rate of all possible waves. This perturbative approach also allows us to include dissipative effects, hence we can locate the instability threshold with good precision. We show that our theoretical growth rates are in quantitative agreement with previous and new direct numerical simulations. We explain how our theory can be used to estimate a lower bound on cell size beneath which metal pad roll instability is unlikely.

Dynamic Volumography of Cylindrical Li-Ion Battery Cells by Watching Its Breath During Cycling

Dynamic Volumography of Cylindrical Li-Ion Battery Cells by Watching Its Breath During Cycling

Towards Determining an Engineering Stress-Strain Curve and Damage of the Cylindrical Lithium-Ion Battery Using the Cylindrical Indentation Test

Mechanical internal short circuit (ISC) is one of the significant safety issues in lithium-ion battery design. As a result, it is possible to subject LIB cells to thorough mechanical abuse tests to determine when and why failure may occur. The indentation test is a recommended loading condition for evaluating mechanical damage and ISC. In this study, 18,650 cylindrical battery cells underwent indentation tests and a voltage reduction following the peak force identified by the ISC. Due to the complexity of the contact surface shape between two cylinders (LIB cell and indenter), a new phenomenological analytical model is proposed to measure the projected contact area, which the FEM model confirms. Moreover, the stress-strain curve and Young’s modulus reduction were calculated from the load-depth data. In contrast to previously published models, the model developed in this paper assumes anisotropic hyperelasticity (the transversely isotropic case) and predicts the growing load-carrying capacity (scalar damage), whose variation is regulated by the Caputo-Almeida fractional derivative.

Measurement of thermophysical parameters and thermal modeling of 21,700 cylindrical battery

There is temperature unevenness inside the operating battery, and the internal temperature distribution of the battery has gradually attracted attention. To establish a thermal model of the 21,700 cylindrical battery that can reflect the internal temperature distribution, thermophysical parameters including anisotropic thermal conductivity and specific heat capacity are tested through experiments. The thermal model includes the heat generation part and heat transfer part. Thermophysical parameters are essential for the heat transfer part. Hybrid pulse power characterization (HPPC) tests are carried out to obtain battery internal resistance, and the entropy coefficient of the battery is also obtained by tests. Internal resistance and entropy coefficient data are used as inputs for the battery heat generation part. The core temperature and surface temperature of the operating battery are measured by the thermocouple embedded inside the battery and the thermocouple pasted on the battery surface. The calculated core and surface temperatures from the battery thermal model are both in good agreement with the measured temperature results. The maximum core temperature of 2C discharging battery is about 60 °C and the maximum temperature difference inside the 21,700 battery reaches 3 °C. The established simulation model can be used for extended research work. When heat dissipation is enhanced by increasing the convection heat transfer coefficient, the overall temperature of the battery decreases but the temperature non-uniformity inside the battery is aggravated.

Effect of splitter damper on airflow conduction for thermal management of a lithium-ion battery cooling system with plate and cylindrical batteries

BackgroundThis paper simulates a lithium-ion battery pack (BRK) with cylindrical and plate batteries in an air duct. The batteries are arranged in rows of cylinders and plates in the BRK. A splitter damper is used at the air inlet and outlet in the duct. MethodsThis study was performed in a laminar airflow by changing the length of the splitter damper from 0.2 to 0.5 m, for both oval and triangular shapes of the splitter damper. Effects of various splitter damper settings on the BRK temperature, output air temperature, and heat transfer coefficient have been investigated. The BRK is simulated using COMSOL 6.0 software. Significant findingsAccording to the study's findings, the BRK greatest and lowest mean temperatures were measured along the 0.4 and 0.2 m of the splitter damper's triangular form, respectively. The heat transfer coefficient for the oval shape of the splitter damper was higher than the triangular shape of the splitter damper at all lengths of the splitter damper. The highest heat transfer coefficient is recorded in the oval form of a splitter damper with a length of 0.5 m.

Supplementary material 1 ( SM-1); Main article: Design, properties, and manufacturing of cylindrical Li-ion battery cells – A generic overview

Supplementary material 1 ( SM-1); Main article: Design, properties, and manufacturing of cylindrical Li-ion battery cells – A generic overview

Design, properties, and manufacturing of cylindrical Li-ion battery cells – A generic: Supplementary materials

Design, properties, and manufacturing of cylindrical Li-ion battery cells – A generic: Supplementary materials

Numerical investigation of a compact and lightweight thermal management system with axially mounted cooling tubes for cylindrical lithium-ion battery module

To construct a compact and lightweight cooling system for cylindrical batter module, developing cooling tubes inserted into spaces between batteries is a promising way. Yet, the constant distance kept between adjacent cells in battery array makes the reported weight ratio values not satisfactory enough. Merits and demerits between different battery arrangement modes (staggered and aligned) are also unclear. Therefore, in this work, a novel liquid cooling thermal management system with axially mounted cooling tubes inserted into spaces between tightly assembled batteries is presented to provide a compact and lightweight solution to the cooling of cylindrical battery module. Designs with staggered and aligned battery arrangements are compared. Corresponding results show that design with staggered battery arrangement is superior to the aligned one based on the trade-off of different design requirements including cooling performance, system weight and volume cost. BTMS with staggered design reports a remarkably high performance in terms of the lightweight extent, which only accounts for 5.4 wt% of the battery module, much lower than those in previous studies. Further, extended studies are performed for the optimization of BTMS with staggered battery arrangement and the results could provide useful guidance in the future design of BTMS for cylindrical battery modules.

Comparative study of thermal management systems with different cooling structures for cylindrical battery modules: Side-cooling vs. terminal-cooling

Indirect-cooling through cooling plate is a common way in the design of liquid-based battery thermal management system (BTMS), which can be divided into side-cooling and terminal-cooling according to the position arrangement of the cooling plates. In this work, comparative investigations are performed to analyze the specific merits and demerits between these two cooling structures and further understandings are provided for the heat dissipation mechanisms of BTMSs for the cylindrical battery modules. It is found that the side-cooling BTMS exhibits a better ability in the temperature rise control with a maximum temperature (Tmax) of 30.84 °C at the end of 1 C discharge compared with the terminal-cooling one where corresponding Tmax rises to 35.48 °C. But meanwhile, it encounters an inherent drawback on the temperature uniformity with a maximum temperature difference (ΔTmax) of 5.76 °C after 1 h discharging due to the low radial thermal conductivity of the batteries, which forms a significant thermal gradient along its thermal transport paths. In contrast, corresponding ΔTmax in the terminal-cooling case is only 2.86 °C. Effects of coolant velocity and channel number on the heat dissipation performances of the side-cooling and terminal-cooling BTMSs are examined and further, different strategies are proposed and tested for these two cooling structures respectively to ameliorate their heat dissipation performances based on their different characteristics in the heat transport paths and thermal field distributions. The results could provide useful guidance for the future design of BTMS for the cylindrical battery modules.

Thermal management improvement for a pack of cylindrical batteries using nanofluids and topological modifications

Thermal management improvement for a pack of cylindrical batteries using nanofluids and topological modifications

Experimental studies of reciprocating liquid immersion cooling for 18650 lithium-ion battery under fast charging conditions

In this study, the reciprocating liquid immersion cooling has been proposed and tested for cooling the cylindrical lithium-ion battery (LIB) under fast charging conditions. First, the temperature responses of LIB under fast charging conditions with liquid immersion cooling and natural convection are compared. Experimental results show that the reciprocating liquid immersion cooling possesses better heat dissipation performance than natural convection, not only can precisely control the cell temperature to around 50 °C during fast charging, but also can improve the cell temperature uniformity. Meanwhile, the reciprocating system enables rapid cooling of the battery during the resting process, which consequently achieves asymmetric control of high-temperature charging and room temperature discharging. Then, the effects of different charging rates and different charging protocols are explored, and the high-speed photography is used to observe and record the liquid-gas phase transition phenomenon under three different charging rates. Finally, the temperature response and energy consumption analysis of LIB in the fast-charging process with three different assembly schemes are investigated. This study provides preliminary proof for the advantage of applying liquid immersion cooling for LIB under fast charging.