Thermal Benefits Research Articles

Exploring Raw Red Clay as a Supplementary Cementitious Material: Composition, Thermo-Mechanical Performance, Cost, and Environmental Impact

This study explored the potential of natural red clay as a supplementary cementitious material (SCM) to reduce greenhouse gas emissions and costs associated with the cement industry. Given that cement production is one of the largest contributors to global greenhouse gas emissions, developing sustainable alternatives is of paramount importance. Recognizing the environmental impact of cement production, this research investigates the substitution of conventional cement with raw red clay, aiming to balance mechanical performance with enhanced thermal properties and a lower environmental footprint. Through chemical characterization using X-ray Fluorescence (XRF), along with comprehensive mechanical and thermal performance testing, this study identifies the dual role of raw clay in mortar. It was found that incorporating up to 5% by weight of raw clay slightly impacted compressive strength while significantly improving thermal conductivity and diffusivity, cost-efficiency, and environmental sustainability, making it an appealing option for structural applications requiring high mechanical resistance. Conversely, a higher proportion of clay (beyond 5%) compromises compressive strength, but further enhances thermal properties and environmental benefits, suggesting its suitability for applications where low mechanical resistance is acceptable. This investigation highlights the viability of raw clay as a promising SCM, offering a pathway to more sustainable construction materials without the need for energy-intensive processing, thereby contributing to the reduction in the construction sector’s carbon footprint and energy demand.

Hygrothermal and airtightness performance assessment of prefabricated lightweight wall systems for cold climates

Wooden prefabricated wall panels (WPWP) are increasingly used in the residential sector due to their practical and environmental benefits compared to traditional on-site systems. However, there is limited information regarding their influence on the building envelope´s performance, particularly at panel junctions. Therefore, this study investigated the hygrothermal and airtightness performance of two WPWP systems, one standard and one optimized, focusing mainly on panel-to-panel junctions. Laboratory heat and vapor transfer, thermography, and airtightness assessments were conducted over two full-scale prefabricated walls and a reference on-site traditional wall. In addition, hygrothermal simulations were carried out utilizing WUFI Pro, to compare laboratory heat and vapor transfer results with theoretical values. The results showed that the prefabricated walls reduced heat loss through the air leakage sources of the junctions by up to 17.8% and a reduction of air infiltration by up to 76%, compared to the on-site reference. It was also found that using polyurethane foam in panel junctions generated thermal benefits. Still, care should be taken with the amount of polyurethane foam used to avoid increasing relative humidity. In addition, bio-based insulation (hemp fiber) used in the optimized prefabricated wall exhibited adequate hygrothermal performance as it slightly improved the thermal resistance without increasing the risk of interstitial condensation. Overall, the findings demonstrated that wooden prefabricated wall systems can significantly reduce heat loss and air infiltration, highlighting their potential as a hygrothermally efficient alternative to traditional construction methods.

The Impact of Coverage Forms of Exterior Vertical Greening Walls on the Thermal Environmental Benefits of Buildings in Hot and Humid Regions

Architectural vertical green walls can mitigate the urban heat island effect, provide shade and cooling, reduce energy consumption, improve a microclimate, and increase indoor comfort. However, an excessive pursuit of high coverage may diminish the benefit ratio and adversely affect ventilation and lighting. Field measurements were conducted in the hot and humid Guangzhou area to investigate the thermal benefits of external vertical green walls with varying green coverage and diverse layouts, encompassing effects such as shading, insulation, cooling, and humidification. Analyses were conducted using ENVI-met, orthogonal experiments, and SPSS to quantify the moderating effects of planted green coverage (PGC), leaf area density (LAD), and air interstitial layers on the environmental thermal benefits. The results indicated that the cooling and humidifying effects of 100% PGC and 75% PGC were comparable and superior to those of 50% PGC, yet 75% PGC outperformed 100% PGC in terms of indoor humidification. Among the layout modes, the horizontal layout was the most effective for cooling and humidification, followed by the point layout, with the vertical layout being the least effective. A global sensitivity analysis revealed that PGC had the greatest impact on wall cooling and outdoor humidification, LAD significantly influenced humidification, the width of air interstitial layers had a minor impact, and the two architectural vertical greening design ratios of 75% PGC × 4.60 LAD and 75% PGC × 2.70 LAD were particularly effective for cooling and humidification. Incorporating horizontal or point-like layouts can enhance façade design diversity while preserving the desired environmental thermal benefits, thereby contributing to the overall aesthetics of a building.

Effects of Urban Tree Species and Morphological Characteristics on the Thermal Environment: A Case Study in Fuzhou, China

Trees and their morphology can mitigate the urban heat island (UHI) effect, but the impacts of tree species and their two-dimensional (2D) and three-dimensional (3D) morphological characteristics on the thermal environment of residential spaces at the building scale have not been effectively evaluated. This research extracted the data of trees in the spatial range of a 50 m radius of the sampling sites located in a subtropical humid city’s residential area based on unmanned aerial vehicle (UAV) imagery and field measurements. It included Ficus microcarpa L. f., Cinnamomum camphora (L.) J. Presl, and Alstonia scholaris (L.) R. Br. as three typical evergreen tree species and six quantitative indicators of trees, with the number of trees (N) serving as fundamental indicator and mean canopy width (MCW), mean canopy height (MCH), mean tree height (MTH), canopy biomass (CV), and mean canopy biomass (MCV) as morphological characteristic indicators. We analyzed the impact of the six indicators above on two thermal environment parameters: Air temperature (AT) and relative humidity (RH), by correlation analysis and multiple linear regression analysis. Results showed that: (1) F. microcarpa, as a dominant local species, provided more than 65% of the tree canopy volume within the study area (50 m radius buffer zones), and its contribution to cooling and humidification effects was superior to those of C. camphora and A. scholaris. (2) The MTH and CV of F. microcarpa are the key factors influencing daytime AT and RH, respectively, with temporal fluctuation in impact intensity during the spring (May) daytime. (3) The MTH and N of F. microcarpa show the best cooling effect (adjusted R2 = 0.731, p < 0.05) during midday (13:00–14:00 p.m.), while its CV and MTH have the best humidification effect (adjusted R2 = 0.748, p < 0.05) during the morning (9:00–10:00 a.m.) among three typical tree species. The 2D and 3D morphological characteristic indicators effectively describe the impact and variation of tree species on the spring microclimate within small-scale residential spaces. This work provides new insights into the thermal benefits brought by the spatial growth features of trees at the building scale and offers reference for urban residential areas in the planning and management related to tree species selection, canopy maintenance, and the improvement of thermal comfort for inhabitants.

Life Cycle of LiFePO4 Batteries: Production, Recycling, and Market Trends.

Significant attention has focused on olivine-structured LiFePO4 (LFP) as a promising cathode active material (CAM) for lithium-ion batteries. This iron-based compound offers advantages over commonly used Co and Ni due to its lower toxicity abundance, and cost-effectiveness. Despite its current commercial use in energy storage technology, there remains a need for cost-effective production methods to create electrochemically active LiFePO4. Consequently, there is ongoing interest in developing innovative approaches for LiFePO4 production. While LFP batteries exhibit significant thermal stability, cycling performance, and environmental benefits, their growing adoption has increased battery disposal rates. Improper disposal practices for waste LFP batteries result in environmental degradation and the depletion of valuable resources This review comprehensively examines diverse synthesis approaches for generating LFP powders, encompassing conventional methodologies alongside novel procedures. Furthermore, it conducts an in-depth assessment of the methodologies employed in recycling waste LFP batteries. Moreover, it emphasizes the importance of LFP cathode recycling and investigates pretreatment techniques to enhance understanding. Additionally, it provides valuable insights into the recycling process of used LFP batteries, aiming to raise awareness regarding the market for retired LFP batteries and advocate for the enduring sustainability of lithium-ion batteries.

Effects of diverse vegetation assemblages on the thermal behavior of extensive vegetated roofs

Extensive vegetated roofs (EVRs) offer effective nature-based solutions to cities, mitigating thermal extremes induced by urbanization and climate change. A field experiment monitored EVR's thermal regulation in summer and winter. Two sites with contrasting microclimatic conditions in Córdoba city, Argentina, were compared: city center (Core of the urban heat island, UHI) and city periphery (Fringe of the UHI). Diverse plant assemblages constituted five treatments to evaluate plant and thermal performance. A Random Forest model analyzed the contributions of various factors to thermal benefits. All treatments showed > 60 % plant survival rates, and four treatments achieved > 90 % coverage. In winter, the assemblages, including succulents, herbs, and graminoids, offer effective thermal regulation. In summer, thermal performance differed between the two sites. At the Fringe, the native flora (herbaceous and graminoids) + herbaceous + succulents, and succulents + graminoids furnished outstanding thermal regulation. Conversely, at the Core, succulents outperformed. The coverage was the dominant variable for predicting thermal performance, followed by season and location. The findings provide the basis for designing EVRs to optimize thermal benefits.

Numerical evaluation of ground source heat pumps in a thawing permafrost region

Permafrost degradation poses significant environmental and geological challenges in Arctic and subarctic regions, particularly in areas like Umiujaq, Canada. The warming climate leads to thawing permafrost, causing ground instability, disrupting hydrology, and impacting local built environment. This study evaluates the use of Ground Source Heat Pump (GSHP) operation for mitigating ground subsidence in a permafrost region using a two-dimensional Thermo-Hydro-Mechanical (THM) coupled finite element analysis considering the ground poro-elastic and poro-plastic responses. The research uses a single-well scenario to demonstrate the interactions among thermal, hydraulic, and mechanical processes. The impact of GSHP operation under different temperature management strategies, including a scenario with a constant GSHP temperature of −5 °C throughout the year is numerically investigated. Results indicate that GSHP operation exacerbates ground deformation near the borehole, particularly during winter months. However, maintaining GSHP operation throughout the entire year can mitigate extreme subsidence fluctuations, leading to a more stable subsurface environment. While GSHP systems provide effective thermal regulation, their operation can introduce mechanical stresses that potentially disturb the ground close to the borehole. Therefore, careful design, operation, and further research are essential to balance thermal benefits with ground stability in permafrost regions.

Thermal comfort benefits, energy efficiency, and occupant regulation behaviour in four types of personal heating within the built environment

The conventional approach to creating a uniform and stable thermal environment cannot guarantee the required thermal satisfaction rate and consumes significant energy. Personal comfort systems (PCS) offer a promising solution for office buildings. However, practical guidelines for selecting and operating PCS based on current studies remain elusive. In this study, 28 male participants were exposed to three cold conditions (16, 18, and 20 °C) and separately used four personal heating devices (PHDs): a warm air blower (WB), heated table mat (HM), heated cushion (HC), and leg warmer (LW). Variations in the subjective perception, skin temperature, heating setting adjustments, and operating parameters were monitored. The best improvements in overall thermal sensation under 16, 18, and 20 °C were achieved by HC (ΔOTSV = 0.97), WB (ΔOTSV = 0.85), and HM (ΔOTSV = 0.57), respectively. The energy consumption required to achieve the same thermal comfort benefit differed among the four PHDs. The corrective energy and power of WB, LW, HM, and HC were 64.0 W/K, 42.0 W/K, 14.0 W/K, and 7.9 W/K at 16 °C, respectively. The relationships between the overall thermal benefits of four devices and operating parameters were established to obtain the lower thresholds and suggested values of the heating parameters under different cold conditions. Advice on the automatic control for PHDs was proposed, including the limited air temperature for activation authority, activation priority order in the multi-device scenario, and initial heating settings. Integrating automated PCS with existing building management systems can achieve microenvironmental management, enhancing comfort and energy conservation.

Do Bewick´s Wren (Thryomanes bewickii) nestlings experience thermal stress in nest-boxes in a tropical urban city?

Urban areas present thermal environments that may be challenging for altricial nestlings, particularly in early development. We aimed to evaluate whether altricial Bewick's Wren (Thryomanes bewickii) nestlings experienced thermal stress in the nest-box during the early- and late-developmental stages. We determined the thermoregulatory set point (thermoneutral range) of nestlings by measuring cloacal body temperature of five nestlings from three nests, every other day from hatching until they fledged. We also exposed nestlings to a thermal challenge from day 5 to determine the age of endothermy. We used dataloggers to determine the thermal environment inside and outside of three nest-boxes, and obtained the operative temperature for nestlings in the nest-box using 3D-printed models corresponding to early- and late-developmental stages. Ambient temperatures inside the nest box fluctuated throughout the day, being colder at night just before day-break (min range: 10.4°C – 10.8°C), and hotter in the afternoon (max range: 25.8°C - 28.3°C). However, temperatures in the nest-box did not reach the extreme high and low outside temperatures, and were warmer at night. Nestlings reached age of endothermy at 9 ± 2.3 days after hatching, and showed a thermoneutral range of body temperature above ambient temperatures in the nest-box. Operative temperatures of models in the nest-box closely followed ambient temperatures, and were below nestlings´ thermoneutral range. Therefore, nestlings could experience thermal stress when parents do not provide additional buffering while off the nest for foraging. Although nest-boxes provide limited thermal benefits for nesting birds in tropical cities, they still provide valuable nesting and roosting sites where natural cavities are limited in availability.

Thermo-economic analysis of a pumped thermal energy storage combining cooling, heating and power system coupled with photovoltaic thermal collector: Exploration of low-grade thermal energy storage

As renewable energy penetration grows, traditional power systems face significant challenges due to their intermittency and volatility. Pumped thermal energy storage (PTES) is a potential energy storage technology that has a low specific cost and geographical restriction. In this paper, a PTES system which is coupled with solar photovoltaic thermal (PVT) collectors is proposed to satisfy the demand for cooling, heating and electricity supply, and achieve energy cascade utilization. An ejector refrigeration cycle and the turbine extraction heating are accompanied with a PTES system. Thermodynamic analysis of the system is performed by evaluating the influence of key parameters on system performances for 1 MW power output. The economic analysis adopted levelized cost of energy storage (LCOS), which mainly includes investment costs, operation and maintenance costs and system depreciation. The results show that the maximum amplification of roundtrip efficiency with PVT is 12.04 % compared to the system without PVT. Moreover, the maximum average power generation benefit of PVT is 4.85 %. The increase in cold energy storage tank temperature can effectively improve the roundtrip efficiency of the system. The lower cold energy storage tank temperature and higher hot energy storage tank temperature have a negative impact on system thermal efficiency (ηthermal) but benefits for LCOS. Multi-objective optimization is carried out to obtain the optimal design performance that ηthermal and LCOS are 51.06 % and 0.533$/kWh respectively.

Unusually high thermal conductivity in suspended monolayer MoSi2N4

Two-dimensional semiconductors with high thermal conductivity and charge carrier mobility are of great importance for next-generation electronic and optoelectronic devices. However, constrained by the long-held Slack’s criteria, the reported two-dimensional semiconductors such as monolayers of MoS2, WS2, MoSe2, WSe2 and black phosphorus suffer from much lower thermal conductivity than silicon (~142 W·m–1·K–1) because of the complex crystal structure, large average atomic mass and relatively weak chemical bonds. Despite the more complex crystal structure, the recently emerging monolayer MoSi2N4 semiconductor has been predicted to have high thermal conductivity and charge carrier mobility simultaneously. In this work, using a noncontact optothermal Raman technique, we experimentally measure a high thermal conductivity of ~173 W·m–1·K–1 at room temperature for suspended monolayer MoSi2N4 grown by chemical vapor deposition. First-principles calculations reveal that such unusually high thermal conductivity benefits from the high Debye temperature and small Grüneisen parameter of MoSi2N4, both of which are strongly dependent on the high Young’s modulus induced by the outmost Si-N bilayers. Our study not only establishes monolayer MoSi2N4 as a benchmark 2D semiconductor for next-generation electronic and optoelectronic devices, but also provides an insight into the design of 2D materials for efficient heat conduction.

Practical design of an optical filter for thermal management of photovoltaic modules

AbstractThis work presents a practical approach to designing an optical filter for thermal management for photovoltaic modules. The approach emphasizes the practicality of manufacturing over optical performance. Simulation work demonstrates that, for an interdigitated back contact solar cell architecture, complete rejection of infrared radiation offers limited thermal benefits requiring highly complex optical filter designs. An alternative approach consists of reducing thermalization losses by providing reflectance at lower wavelength values. An optical filter design that fulfills this requirement is possible using simple structures based on two materials and taking advantage of the harmonics present in quarter wavelength optical thickness designs. The filter is later optimized for angular performance via second‐order algorithms, resulting in a device consisting of only 15 thin‐film layers. Performance simulations on two locations, Delft (the Netherlands) and Singapore, estimate a temperature reduction of 2.20°C and 2.45°C, respectively. In a single year, the optical loss produced by the filter is not compensated via temperature reduction. However, improvements in the annual degradation rate show that in Singapore, the overall effect of the filter on the lifetime DC energy yield is positive.

Role of supplementary cementiteous materials in mitigating heat of hydration in mass concrete elements

Concrete’s heat of hydration can cause wide restraint cracks, delayed ettringite formation and low strength. The heat of hydration in concrete poses significant challenges in the construction industry particularly in mass concrete elements. Addressing these challenges, the utilization of supplementary cementitious materials (SCMs) such as fly ash (FA) and ground granulated blast furnace slag (GBFS) in concrete has been extensively studied for their individual contributions in modifying the heat of hydration. However, the comparative effectiveness of FA and GBFS, as well as the implications of their combined use in a ternary blend mix, remain underexplored. This study aims to bridge this gap by investigating the heat evolution profiles of concrete blends incorporating varying proportions of FA, GBFS, and general Portland cement (GPC). Through a series of semi-adiabatic tests, the study evaluates the hydration kinetics, maximum temperature rise, and time delay to peak temperature for binary and ternary mixes. The findings suggest that while individual SCMs like FA and GBFS offer distinct thermal benefits, their combined use in a ternary blend presents a synergistic effect, optimizing heat management in concrete. In essence, this study not only underlines the potential of ternary blends in enhancing concrete's thermal performance but also emphasizes their role in promoting sustainable and resilient construction practices.

From Block to City Scale: Greenery’s Contribution to Cooling the Urban Environment

Urban greenery is a strategy to improve the thermal environment in urban areas affected by heat islands and global warming. These phenomena can harm the citizens’ quality of life. Researchers have investigated the thermal benefits of urban vegetation, but only a few have explored its complexities across diverse urban scales. Understanding these variations is critical for precise analysis, customized solutions, efficient resource allocation, and enhancing urban living quality while promoting sustainability and climate resilience. This paper reviews 250 scientific articles about the relationship between greenspace and the urban thermal environment published between 2010 and 2023 through urban scales. It summarizes the parameters and findings of greenery’s contribution to cooling the urban environment. The data reveal that most studies concentrated on the block scale, public open spaces, neighborhoods, parks, grouped vegetation, mixed arrangements, high vegetation, spatial parameters, and the use of air temperature data to report their findings. The cooling-effect evidence shows that the block scale has an average mitigation range of 0.7–2.7 °C, the neighborhood scale of 1.1–2.9 °C, and the city scale of 0.5–2.2 °C. Furthermore, it is critical to define reliable research methods and perform thorough software validation to assess model performance and establish guidelines for urban-landscape design accurately.

Thermal benefits of roost site selection in a small forest owl

Thermal benefits of roost site selection in a small forest owl

Performance of power dissipation on semiconductor module for different configuration of heat SINK with thermal pad

An experimental and numerical investigation to assess the impact of the number of fin arrangements on heat dissipation and its subsequent influence on junction temperature under natural convection. The experimental phase incorporated a thermal pad with a thermal conductivity of 12 W/mK and an aluminum heat spreader measuring (17x16.5) mm. By utilizing the finite volume method (FVM), a numerical model was developed that closely resembles the experimental setup, with errors for temperature package and heat spreader measured at 0.08% and 4.49%, respectively. The analysis was carried out for five different numbers of fins, specifically s1=4fins, s2=6fins, s3=8fins, s4=10fins and s5=12fins. According to the numerical analysis, the increase in the number of fins from 4 to 12 led to a reduction in the average junction temperature from 79.11 °C to 75.97 °C. This denotes a decrease of 3.97% in the average junction temperature. The inclusion of fins on the heat spreader brought about an upsurge in conduction resistance from 55.77 °C/W to 56.19 °C/W, while the convective resistance observed a decline from 152.35 °C/W to 139.62 °C/W. By increasing the number of fins from 4 to 12, the Nusselt number experiences a monotonic decrease from 14.44 to 14.141 due to the reduction in fin-to-fin spacing. As a result, this would lead to a decrease in the natural convection flow. Hence, it was concluded that increasing number of fins beyond the optimal number of fins, signifying the point where thermal benefits become insignificant. The results of this study yield significant insights into the optimization and design of thermal solutions for semiconductor modules, ultimately providing a pathway to boost their operational efficiency and longevity in real-world applications.

Hybrid battery thermal management system of phase change materials integrated with aluminum fins and forced air

AbstractDue to its high self‐heat rate, most researchers have avoided using lithium cobalt oxide (LiCoO2) in their work, although, major car companies use it to power some car models because of its high‐power density. A thermal management system benefits from phase change material (PCM) and serves as a reliable cooling system to ensure the safety, performance, and lifespan of Li‐ion batteries. In this study, we conducted an experimental investigation of a new hybrid battery thermal management system (BTMS) using PCM combined with aluminum fins and forced air to enhance the cooling performance of Li‐ion battery type 18 650 LiCoO2. Furthermore, the hybrid model's thermal behaviors are compared with other models that use only air or PCM for cooling. The cooling performance of different BTMS models was tested under a high temperature of 40°C and various discharge rates, as well as, various air velocities. The results demonstrate that the hybrid model effectively minimizes the battery heat accumulation and can reduce the maximum operating temperature by 1.5°C, 5.5°C, and 9.5°C compared to the air‐cooling model and by 2.8°C, 5.1°C, and 16.1°C compared to the PCM model for discharge of 1C, 2C, and 3C rates, respectively. Furthermore, the maximum temperature difference within the battery pack did not surpass 3.1°C with our hybrid model. Moreover, the use of our model has a significant advantage in minimizing the air‐cooling power consumption by 89%.

Enhancing Lighting Efficiency in Kost's Rooms by Utilizing Bamboo Panels

Abstract: This research paper examines the sustainability aspects of bamboo as a versatile building material, with a particular emphasis on its potential to enhance lighting efficiency in construction. Sustainability in building construction necessitates eco-friendliness, affordability, versatility, and durability, all of which bamboo embodies. Beyond its well-documented thermal benefits, bamboo's rapid growth rate, adaptability to diverse climates, and inherent qualities position it as an eco-conscious choice for building materials. Notably, bamboo offers advantages such as high yield, environmental friendliness, lightweight properties, and rapid maturation for harvesting, making it a cost-effective option. This research delves into the key attributes and noteworthy applications of bamboo, including its innovative use in student boarding houses around Universitas Islam Indonesia. Through rigorous research, Bamboyasa workshop and experiments, we identified one of the 3 bamboo panels we made then selected the most promising panel for practical experimentation, focusing on bamboo panel technologies then modify the design to enhance the daylighting and thermal target. Our aim is to harness bamboo's unique characteristics to enhance human comfort and create sustainable building components tailored to lighting efficiency.

Effect of lead-free solder thermal interface material thickness on the reliability of electronic components in a random vibration environment

The reliability of electronic components has persistently posed challenges for engineers. This study addresses the critical need of understanding the impact of random vibration on the reliability of lead-free solder as thermal interface materials (TIM) within electronic components. ANSYS software was deployed to design, develop, and simulate the electronic model, with a focus on the TIM. SAC405 lead-free solder served as the TIM, its thickness was varied between 0.01 to 0.06 mm (at 0.01 mm intervals). The results from this investigation reveal relevant correlations. As the TIM thickness increases, there's a noticeable reduction in stress and strain while the deformation increases. Remarkably, a direct relationship emerges between TIM thickness and fatigue life; thicker TIM correlates with increased fatigue life. In addition, at a TIM thickness of 0.01 mm, the fatigue life measurements were 2.76 x 104, 1.63 x 104, and 0.792 x 104 for Equations 1, 2, and 3, respectively. These findings carry profound implications for engineers, serving as a guiding framework to aid in the selection of optimal TIM thickness for electronic components if lead-free solders are used as TIM. Understanding these trade-offs between stress, strain, deformation, and fatigue life is pivotal, empowering engineers to make informed decisions during electronic system design and development, ultimately enhancing overall reliability. Using lead-free solders as TIM in electronic applications is proposed by this study due to the thermal and reliability benefits presented.

Effectiveness of Thermal Interface Materials on Electrical Machines Thermal Performance With Heat Pipes

Thermal issue has always been a major concern in motor design. Heat pipes (HPs) have been applied in electrical machines with remarkable cooling effects reported. However, critical factors that affect HP thermal benefits have rarely been studied, such as limited contact area between HPs and heat sources, which may lead to high thermal resistance and degrade motor thermal performance. Due to limited thermal conductivities, conventional motor thermal interface materials (TIMs), such as epoxy resin, fail to maximize HP thermal benefits and minimize motor temperature rise. In this case, new TIMs with outstanding thermal properties that have not been used in electrical machines, such as thermal grease and adhesive, are potential candidates to address this issue, while their thermal impact is still unclear. This article conducts both experiments and thermal analyses to quantify the effects of TIM on motor cooling performance. Firstly, the thermal properties of ten typical TIMs in four categories are experimentally characterized. Then, the selected TIMs are applied to a stator-winding assembly with HP to evaluate their thermal impact on motor cooling performance under different cooling conditions. Finally, practical guidelines are given for TIM selection in electrical machines with HPs or other cooling media.