Thermal Management Of Li-ion Batteries Research Articles

Expression of concern for article entitled “Numerical analysis of pressure drop and heat transfer of a non-Newtonian nanofluids in a Li-ion battery thermal management system (BTMS) using bionic geometries”

Expression of concern for article entitled “Numerical analysis of pressure drop and heat transfer of a non-Newtonian nanofluids in a Li-ion battery thermal management system (BTMS) using bionic geometries”

Thermal management system for stable EV battery operation with composite phase change materials

Li-ion battery has been one of the cornerstone of the mobile era especially given the burst sales of Electrical vehicles (EV) which have eclipsed that of internal combustion engine vehicles over last decade. While extensive advances in smart production and technologies make it booming to the development of EV, there have been frequently reported fatal fire incidents originated from excessive thermal hazards of Li-ion batteries. In this paper, we developed a new Li-ion battery thermal management system, by making use of porous Aluminum structure as skeleton and Phase Change Materials (PCMs) as filler, to maintain its optimal operating temperature below 35 °C within a small tolerance range of ± 1 °C fluctuation by continuous heat absorption and heat release during the phase changes of the PCM. The thermal stress and energy consumption in the internal battery pack caused by temperature fluctuations can thus be reduced, ultimately sustaining the overall functional life span of the battery. We envision that our work will advance the operation of EV battery and incubate a versatile framework ranging from thermal management to battery assembly.

Thermal management of Li-ion battery by using eutectic mixture of phase-change materials

Lithium-ion batteries have a wide range of applications in portable electronic devices, global positioning systems, and the automobile industry due to their remarkable attributes like high energy density, long life cycle, higher efficiency, low self-discharging, and worthier operational performance. Although under different vigilant operating parameters, lithium-ion batteries generate a significant amount of heat, which deteriorates their performance and can lead to thermal runaway. To mitigate this issue and to improve safety, battery life, capacity, and overall performance, a robust thermal management system is very necessary. This study scrutinizes the effect of a passive cooling method using phase-change materials and their eutectic mixture on a 2600 mAh lithium-ion battery pack during the charging and discharging at various C-rates (1C, 1.5C, and 2C). Phase-change materials used in the experimentation are salt hydrates namely calcium nitrate tetrahydrate and zinc nitrate hexahydrate and their eutectic mixture contains 55 % calcium nitrate tetrahydrate and 45 % zinc nitrate hexahydrate. Experimental results reveal that without the usage of any phase-change material, the highest temperature was recorded at a 2C rate due to high current, with cell 5 recording a temperature of 60.98 °C. Zinc nitrate hexahydrate reduced the temperature by 18.98 °C to maintain it at 42 °C, and calcium nitrate tetrahydrate led to a temperature drop of 14.48 °C, maintaining it at 46.50 °C. The eutectic mixture caused a temperature reduction of 21.97 °C, maintaining it at 39.01 °C. The results of this study illustrate that the implementation of eutectic mixture as a phase-change material diminishes both the maximum surface temperature and the temperature gradient. This implies its efficacy as a viable material for the cooling of battery packs.

A comprehensive study for evaluation of cell cooling coefficient of the batteries of fixed sizes and batteries with defects in manufacturing

For the evaluation of cooling performance of Li-ion battery thermal management systems, the commonly used metrics are lumped thermal conductivity, thermal conductance, Biot number, etc. However, such metrics are limited to describing the thermal performance of Lithium-ion batteries (LIBs) and expressing the heat rejection from a body generating heat within its volume. In this perspective, a new metric, such as cell cooling coefficient (CCC), can be introduced to measure the heat rejection capability of cells, which can be used to formulate efficient thermal management strategies. However, limited works describe the system's thermal performance based on CCC, which needs thorough investigation. This work illustrates a comprehensive heat conduction simulation using heat flux through electrode tabs, average temperature of electrode tabs, max cell temperature, total CCC, and the electrode CCC as the thermal indexes to describe the thermal behavior of batteries with five manufacturing defects and study the correlation between heat rejection performance and the CCC of the system. The results of the analysis claim that batteries with different manufacturing defects have different CCC values and thermal performance. Increasing the width of electrode tabs can increase the total CCC of the system, reduce the difference in the electrode CCC values, and further decrease the max cell temperature. The total CCC and the difference in the CCC value of each tab of the battery can be applied to describe the heat rejection performance of the system. The findings of this work can guide further work on optimizing the structure to improve the thermal performance of the cell.

Optimal Control for Thermal Management of Li-ion Batteries via Temperature-Responsive Coolant Flow

Optimal Control for Thermal Management of Li-ion Batteries via Temperature-Responsive Coolant Flow

Thermal management of Li-ion batteries in electric vehicles by nanofluid-filled loop heat pipes

An analytical model is developed to determine the thermal performance of a Loop Heat Pipe filled (LHP) with copper oxide–water and alumina–water nanofluids for battery thermal management in electric vehicles. The thermal performances of the LHP are predicted for different heat loads and nanoparticle concentrations. It is demonstrated that for fast charging operation corresponding to a heat load of 150 W, the LHP ensures evaporator temperatures of less than 60 °C for a heat sink temperature of 40 °C. The heat transport capacity of the LHP is enhanced and the evaporator temperature is deceased by augmenting the nanoparticle concentration. The water–CuO nanofluid-filled LHP performs better than the water–Al2O3 nanofluid-filled one. The addition of the nanoparticles increases the LHP total pressure drop and the driving capillary pressure. The capillary limit of the water–CuO nanofluid-filled LHP is hardly affected by CuO nanoparticle concentration until 6% beyond which the capillary limit starts decreasing. For the water–Al2O3 nanofluid-filled LHP, the capillary limit decreases when Al2O3 nanoparticle concentration increases. Beyond 6% Al2O3 nanoparticle concentration, the capillary limit of the Al2O3-filled LHP becomes lower than the water-filled one.

Thermal stability of a two-dimensional multilayer diffusion-reaction problem

Multilayer diffusion-reaction problems appear commonly in heat and mass transfer analysis, including in thermal management of Li-ion batteries, drug delivery and reacting systems. Thermal stability of diffusion-reaction problems is of much interest due to the potential for thermal runaway in such systems. While there is some past work on investigating thermal instability in a one-dimensional multilayer body, practical systems such as Li-ion cells are often two- or even three-dimensional. Therefore, it is important to develop a theoretical understanding of when a two-dimensional multilayer diffusion-reaction system may be thermally unstable. This work addresses this important question by deriving a solution for the transient temperature field in this problem, followed by pole analysis in the Laplace domain. An explicit threshold for thermal stability of the system is determined on the basis of the determinants associated with a set of algebraic equations. The impact of key non-dimensional numbers on thermal stability is determined, including those associated with heat generation and boundary cooling, as well as ratios of thermal properties of the layers. Good agreement with past papers for special cases of the general problem considered here is shown. A stability curve that separates stable and unstable regions in the thermal design space of a two-dimensional two-layered body, such as a stack of Li-ion cells is presented. This work extends the state-of-the-art in the theoretical understanding of thermal stability, and may also contribute towards design for safety of practical engineering systems.

Analysis of hybrid active-passive prismatic Li-ion battery thermal management system using phase change materials with porous-filled mini-channels

The rapid expansion of electric vehicles (EVs) has created a significant demand for lithium-ion batteries (LIBs). However, ensuring safety and preventing thermal degradation of LIBs pose challenges to their overall performance and lifespan. Efficient battery thermal management systems (BTMS) are crucial in achieving long-lasting batteries with high energy density. Thermal management procedures are categorized into active and passive approaches. While active cooling methods are crucial, they consume power. Instead, passive cooling methods are not as influential in fulfilling all roles. This study examines a combination of active (mini-channel) and passive (PCM heat sink) techniques. The effects of employing a porous medium inside the mini-channel are also analyzed to enhance the heat exchange. Influences of different factors, including Darcy number, material, the thickness of porous media, and inlet velocity of mini-channel flow in multiple discharge rates (1C, 2C, 3C), are examined. Outcomes show the PCM heat sink itself can lessen the maximum temperature by about 4.2 to 5 K in different inlet velocities. The hybrid porous-filled channel and PCM heat sink can mitigate the maximum temperature by about 13 K in different inlet velocities and at the maximum discharge rate (3C) at the expense of about 14 % higher pumping power in different conditions.

Investigations of Li-Ion Battery Thermal Management Systems Based on Heat Pipes: A Review

Investigations of Li-Ion Battery Thermal Management Systems Based on Heat Pipes: A Review

Experimental investigation of pressure effect on the PCM performance in Li-ion battery thermal management system

To control the maximum temperature in Li-ion batteries, it is inevitable to use a battery thermal management system (BTMS). Compared to the traditional methods, the phase change material (PCM) does not consume energy, so thermal management based on PCM is the best compromise between costs, integration, efficiency, and life cycle. To enhance the performance of PCMs, there are three methods available: 1) improve their thermal conductivity, 2) use other thermal management systems in parallel with them, and 3) enhance their energy storage capacity. The aim of this research is to introduce pressure as a tool to increase the energy storage capability in polyethylene-glycol-1000 (PEG1000) PCM to achieve a more efficient BTMS. The Box-Behnken design was performed by considering the input parameters, including the initial temperature of the cell (30–37 °C), pressure (100–500 kPa), and the discharge rate (1-7C). The effects of input variables are investigated on the maximum temperature, depth of discharge, and discharge energy during the discharge process of a single 18,650 cylindrical cell. The cell temperature of 63 °C was considered as a permissible maximum temperature limit. The results show when the discharge was at 7 C, the cell was able to discharge for almost twice as long when subjected to the pressure of 500 kPa in comparison to when it was under atmospheric pressure. Moreover, increasing the pressure from 100 to 500 kPa almost increased the depth of discharge by nearly 10 % and doubled the extracted energy.

Numerical investigation on the thermal management of Li-ion batteries for electric vehicles considering the cooling media with phase change for the auxiliary use

This study investigates the thermal management of a battery module of an electric vehicle for the recovery of waste heat. In the evaluation of this waste heat, a two-phase flow system is used to provide a more effective heat transfer. The battery system was formed of 6 serial connected prismatic Lithium-Ion cells. It was aimed to design a 134.55 kW electric vehicle battery system. For this aim, 360 battery modules were used. The maximum amount of waste heat obtained from these modules was recorded as 6.192 kW. Since it is aimed to use this waste heat in the auxiliary cycles such as air conditioning and extra electricity production, R600a was used as the cooling media. A parametric study was conducted for different discharging rates (C) and depths of discharging (DoD) through computational fluid dynamics (CFD) for performing the thermal analysis of the battery module. The heat transfer coefficient was determined ranging between 1.10 and 5.49 kWm−2 K−1. The cooled module temperature was recorded between 290.93 K and 317.31 K, whereas it was recorded as 332.57 K for the non-cooled system. For secondary purposes, the refrigerant mass rate ranging between 0.2760 kgs−1 and 0.6559 kgs−1 was obtained in a temperature range of 283 K and 313 K.

Flexible phase change materials for low temperature thermal management in lithium-ion batteries

The performance of Li-ion batteries can degrade dramatically at cold ambient temperatures. The excess heat generated during battery operation can be stored by PCMs and then released at low ambient temperatures to insulate the battery. However, PCMs inevitably suffer from easy leakage and poor adaptability. In this study, we prepared a novel Oct/SEBS composite PCM and applied it in a low-temperature Li-ion battery thermal management system. The prepared Oct/SEBS has good shape stability, a sufficiently high latent heat (187.7 J/g), and thermally induced flexibility properties. In addition, the BTMS containing CPCM can exhibit excellent thermal insulation performance, which can insulate the Li-ion battery for more than 30 min even at −20 °C and increase the discharge capacity from 3.78 Ah to 5.49 Ah, which is very beneficial for the operation of the Li-ion battery at low temperatures.

Computational analysis of preheating cylindrical lithium-ion batteries with fin-assisted phase change material

The existing conventional vehicle transportation landscape in India is grappling with challenges stemming from extensive air pollution, health risks, surging oil prices, limited fossil fuel resources, substantial oil import expenses and energy volatility. To counter these issues, Electric Vehicles (EVs) are progressively replacing internal combustion engines, offering a promising route toward decarbonization and mitigating climate concerns. EVs rely on electric motors powered by batteries, predominantly Lithium-ion batteries (LIBs), known for their superior attributes such as low self-discharge, high energy density and extended life cycle. Nevertheless, LIB performance is significantly influenced by operating temperatures, with suboptimal conditions leading to decreased efficiency, power loss and faster aging. Addressing this, an effective Battery Thermal Management System (BTMS) becomes crucial to maintain batteries at optimal temperatures, enhancing their efficiency and safety. This study focuses on a computational analysis of passive heating systems employing Fins and Phase Change Materials (PCM) for 18650 Li-ion battery thermal management at low temperatures, with specific attention to battery module analysis. Numerical analysis using ANSYS FLUENT investigates the influence of varying PCM thickness on heat transfer, predicting temperature distribution and discussing its impact on battery output performance.

Effect of mechanical vibration on thermal performance of PCM-fin structure Li-ion battery thermal management system under high-rate discharge and high-temperature environment

The PCM-fin structure battery thermal management system (PCM-fin structure BTMS) has garnered significant attention due to its exceptional thermal performance. However, existing research has overlooked the presence of mechanical vibration that is inevitable in the operational environment of electric vehicle BTMS. This study aims to address this knowledge gap by comprehensively analyzing the effect of mechanical vibration on the thermal performance of the BTMS under high-temperature and high-rate discharge condition. Four novel findings are introduced for the first time: Firstly, mechanical vibration can significantly enhance the thermal performance of the BTMS, and the enhancement effect is more pronounced compared to the PCM-based BTMS without fins. Secondly, mechanical vibration also affects the ideal fin quantity for the BTMS. Under no vibration condition, the ideal quantity of fins is 10, while under mechanical vibration condition of 30 mm amplitude and 20 Hz frequency, the ideal fin quantity is 8. Thirdly, the thermal performance of the BTMS can be improved by increasing the vibration amplitude. Nevertheless, once a certain high value is reached, further increasing the vibration amplitude has a negligible effect on the enhancement of thermal performance. Lastly, even under low vibration frequency of 10 Hz, the BTMS can still perform well. However, as the vibration frequency increases, the thermal performance of the BTMS becomes progressively less sensitive to changes in vibration frequency. This work can provide guidance for the design and practical application of PCM-fin structure BTMS.

Lithium-ion battery thermal management for electric vehicles using phase change material: A review

Lithium-ion (Li-ion) batteries in electric vehicles (EVs) present a promising solution to energy and environmental challenges. These batteries offer numerous advantages, including high energy density, endurance, minimum self-discharge, and long life, accelerating their adoption in EVs. High temperatures can lead to thermal runaways, causing safety hazards such as short circuits and explosions. Conversely, low temperatures can trigger the formation of lithium dendrites, resulting in failures and operational issues. To address these concerns, phase change materials (PCM) are being explored to store and release thermal energy without significant temperature changes. This review paper presents an overview of PCM for battery thermal management systems. It examines and compares thermal management strategies employed for Li-ion batteries, highlighting their merits, drawbacks, and cost-effectiveness. Different types of heating and cooling mechanism are summarized. Furthermore, the study discusses potential future developments in the field to enhance the thermal management of Li-ion batteries in EVs.

Optimizing PCM-fin structure Li-ion battery thermal management system under mechanical vibrational condition: A comparative study

The thermal management method combining Phase Change Material (PCM) and metal fins has become a highly efficient and promising cooling method for lithium-ion battery (LIB), which is currently a hot research topic. However, the working environment of the Battery Thermal Management System (BTMS) for electric vehicles inevitably involves mechanical vibrations, which have been neglected in previous studies on PCM-fin structure BTMS. This research is the first to look into the effect of mechanical vibrations on the thermal performance of PCM-fin structure BTMS and compare it with the thermal performance of the BTMS under non-vibration condition. The outcomes indicated that the presence of mechanical vibration affects the optimal parameters of the fin structure in the PCM-fin structure BTMS. Compared with the case of the BTMS with optimal fin parameters under non-vibration condition, under vibration condition with an amplitude of 30 mm and a frequency of 30 Hz, it is possible to reduce the weight of the BTMS by 5.67% while further reducing the highest LIB temperature by 0.55 K and achieving a more uniform temperature distribution. This is an important finding that mechanical vibration is a critical factor that must be taken into account during the design of the BTMS fin parameters and has a dramatically positive effect on the lightweight optimization of the BTMS. This research can act as a guide for the practical engineering application of PCM-fin structure BTMS and promote the development of lightweight electric vehicles.

Experimental studies on two-phase immersion liquid cooling for Li-ion battery thermal management

The thermal management of lithium-ion batteries (LIBs) has become a critical topic in the energy storage and automotive industries. Among the various cooling methods, two-phase submerged liquid cooling is known to be the most efficient solution, as it delivers a high heat dissipation rate by utilizing the latent heat from the liquid-to-vapor phase change. In this study, a novel two-phase liquid immersion system was proposed, and the cooling performance of an 18650 LIB was investigated to evaluate the effects of thermal management on the performance of the battery pack. Four cooling strategies, namely natural, forced convection, mineral oil (single-phase), and SF33 fluid (two-phase) cooling, were compared under different discharge rates and dynamic load conditions. The results suggest that two-phase immersion cooling with SF33 fluid was highly effective to keep the cell temperature under 34 °C under all tested conditions, and the temperature change of the battery did not exceed 5 °C. A large amount of heat from the battery during high C discharge was absorbed by the boiling of SF33, allowing it to effectively maintain the cell temperature in an optimal temperature range (33–34 °C). Finally, the mechanism of pool heat transfer was determined through visual analysis. Initially, small bubbles appeared near the wires and battery terminals, which acted as gasification cores. Subsequently, small bubbles arose around the surface of the battery body, most of which grew to reach the interface. Eventually, the vapor condensed near the top condenser coils. This study provides a foundation for the further development of direct two-phase liquid-cooling technology, which can be an effective method for enhancing the life and safety of LIBs.

A Review of Advanced Cooling Strategies for Battery Thermal Management Systems in Electric Vehicles

Electric vehicles (EVs) offer a potential solution to face the global energy crisis and climate change issues in the transportation sector. Currently, lithium-ion (Li-ion) batteries have gained popularity as a source of energy in EVs, owing to several benefits including higher power density. To compete with internal combustion (IC) engine vehicles, the capacity of Li-ion batteries is continuously increasing to improve the efficiency and reliability of EVs. The performance characteristics and safe operations of Li-ion batteries depend on their operating temperature which demands the effective thermal management of Li-ion batteries. The commercially employed cooling strategies have several obstructions to enable the desired thermal management of high-power density batteries with allowable maximum temperature and symmetrical temperature distribution. The efforts are striving in the direction of searching for advanced cooling strategies which could eliminate the limitations of current cooling strategies and be employed in next-generation battery thermal management systems. The present review summarizes numerous research studies that explore advanced cooling strategies for battery thermal management in EVs. Research studies on phase change material cooling and direct liquid cooling for battery thermal management are comprehensively reviewed over the time period of 2018–2023. This review discusses the various experimental and numerical works executed to date on battery thermal management based on the aforementioned cooling strategies. Considering the practical feasibility and drawbacks of phase change material cooling, the focus of the present review is tilted toward the explanation of current research works on direct liquid cooling as an emerging battery thermal management technique. Direct liquid cooling has the potential to achieve the desired battery performance under normal as well as extreme operating conditions. However, extensive research still needs to be executed to commercialize direct liquid cooling as an advanced battery thermal management technique in EVs. The present review would be referred to as one that gives concrete direction in the search for a suitable advanced cooling strategy for battery thermal management in the next generation of EVs.

Liquid cooling plate with drop-shaped deflectors based on Coanda Effect - For Li-ion battery thermal management

Battery thermal management system (BTMS) can maintain the operating temperature and temperature difference of Lithium-ion batteries (LiBs) within the ideal range. In this paper, three kinds of liquid cooling plates with mesh structures (LCP-MSs) were proposed, and they were compared with the LCP with straight channel (LCP-SC). The results show that the LCP-MSs can effectively improve the temperature uniformity of the LiB and reduce the heat concentration. Among the three proposed LCP-MSs, the LCP with drop-shaped deflectors (LCP-DD) is particularly outstanding in reducing the pressure drop (∆P) of coolant. At the same time, in terms of cooling performance, the gap between LCP-DD and the other two LCP-MSs is very small. To further study the cooling performance and ∆P of LCP-DD, structural parameters, number of deflectors, layout of deflectors, and inlet velocity were investigated. The results show that the heat dissipation performance of LCP-DD was improved with the increase of the deflector size/number and the inlet velocity, while ∆P shows an increasing trend. Finally, the orthogonal test was carried out to optimize the design of the proposed LCP-DD. The optimal solution can control the maximum temperature, maximum temperature difference and pressure drop at 301.3 K, 3.1 K, and 251 Pa, respectively.

Experimental study of Li-ion battery thermal management based on the liquid-vapor phase change in direct contact with the cells

Experimental study of Li-ion battery thermal management based on the liquid-vapor phase change in direct contact with the cells