Phase Change Matters RSS


The award-winning Phase Change Matters blog tracks the latest news and research on phase change materials and thermal energy storage. E-mail tips and comments to Ben Welter, communications director at Entropy Solutions. Follow the blog on Twitter at @PureTemp. Subscribe to the monthly PCM newsletter. Or join the discussion on LinkedIn.




Patent application: Battery-cooling heat sink provided with PCM capsule

Ben Welter - Friday, September 20, 2019

U.S. patent application 20190288351 (applicant LG Chem Ltd., Seoul, South Korea):

"A battery module including a battery-cooling heat sink having a PCM capsule. The battery-cooling heat sink provides a uniform temperature of a cooling fluid flowing through the battery module using a PCM capsule, minimizes a temperature variation of the cooling fluid over the entire area of the heat sink formed in the battery module, and prevents the temperature at a cooling fluid outlet of the heat sink from being higher than that of a cooling fluid inlet."

Patent application: Reduced permeability microcapsules

Ben Welter - Friday, September 20, 2019

U.S. patent application 20190275490 (applicant Trucapsol LLC, Bethlehem, Penn.):

Trucapsol patent drawing"Disclosed is a composition including controlled release particles, wherein each of the controlled release particles includes: (a) a core including at least one hydrophobic active ingredient; and (b) a wall at least partially surrounding the core and including: (i) an outer layer including a copolymer of polyacrylamide and polyacrylate; (ii) an intermediate layer under the outer layer and including a polyurea; (iii) an inner layer under the intermediate layer and including an acrylate copolymer; and optionally (iv) an optional outer layer above the outer layer and including a quaternary amine containing moiety, wherein the inner layer is a mesh and the controlled release particles are effective to retain the at least one hydrophobic active ingredient upon exposure to water and effective to release the at least one hydrophobic active ingredient in response to friction. A method for preparing the composition is also disclosed."

Research roundup: Mesoporous silica; nanoencapsulation of oleic acid PCM; flexible crosslinking; more

Ben Welter - Friday, September 20, 2019

From International Journal of Energy Research:

Facile functionalized mesoporous silica using biomimetic method as new matrix for preparation of shape‐stabilized phase‐change material with improved enthalpy
Binary mixtures of fatty alcohols and fatty acid esters as novel solid‐liquid phase change materials

From Journal of Applied Polymer Science:

Phase change material with flexible crosslinking for thermal energy storage

From Journal of Thermal Analysis and Calorimetry:

Nanoencapsulation of oleic acid phase change material with Ag2O nanoparticles-based urea formaldehyde shell for building thermal energy storage

From Renewable Energy:

Enhanced properties of diatomite-based composite phase change materials for thermal energy storage

From Energy:

Perspectives for short-term thermal energy storage using salt hydrates for building heating
Design and construction of mesoporous silica/n-eicosane phase-change nanocomposites for supercooling depression and heat transfer enhancement
Numerical investigations on performance of phase change material Trombe wall in building

From Energy and Buildings:

Potential of energy flexible buildings: evaluation of DSM strategies using building thermal mass
Numerical analysis in a full-scale thermal energy storage tank with dual PCM capsules

From Applied Thermal Engineering:

Experimental determination and fractal modeling of the effective thermal conductivity of autoclave aerated concrete (AAC) impregnated with paraffin for improved thermal storage performance
Preparation and characterization of new nano-particle mixed as thermal storage material
Numerical investigation on integrated thermal management for a lithium-ion battery module with a composite phase change material and liquid cooling

From Chemical Engineering Journal:

Fatty Amines/Graphene Sponge Form-Stable Phase Change Material Composites with Exceptionally High Loading Rates and Energy Density for Thermal Energy Storage

From MATEC Web of Conferences:

Thermal conductivity of aerated concrete (AC) composites containing micro-encapsulated phase change materials [pdf]
Overheating mitigation in buildings: a computational exploration of the potential of phase change materials [pdf]

From Solar Energy:

Experimental study on the thermal performance of capric acid-myristyl alcohol/expanded perlite composite phase change materials for thermal energy storage

From Solar Energy Materials and Solar Cells:

Graphitization as efficient inhibitor of the carbon steel corrosion by molten binary nitrate salt for thermal energy storage at concentrated solar power
A strategy for designing microencapsulated composite phase change thermal storage materials with tunable melting temperature

From Institute of Electronics and Information Engineers 2019 Summer Conference:

Thermal Management System in Electric vehicle Battery Pack Using Phase Change Material

From Materials Chemistry and Physics:

Preparation and thermal properties of n-eicosane/nano-SiO2/expanded graphite composite phase-change material for thermal energy storage

From Sustainable Cities and Society:

Simulative optimization on energy saving performance of phase change panels with different phase transition temperatures

From Thermochimica Acta:

The stability and thermophysical properties of a thermal fluid containing surface-functionalized nanoencapsulated PCM

From International Journal of Heat and Mass Transfer:

Functionalized mesoporous silica as matrix for shape-stabilized phase change materials

From Applied Energy:

Synthesis and characterization of microencapsulated sodium sulfate decahydrate as phase change energy storage materials

From Energy Conversion and Management:

Prototype latent heat storage system with aluminum-silicon as a phase change material and a Stirling engine for electricity generation

From Journal of Solar Energy Engineering:

Experimental Investigation and Numerical Modeling of Room Temperature Control in Buildings by the Implementation of Phase Change Material in the Roof
Suitability Assessment and Experimental Characterization of Phase Change Materials for Energy Conservation in Indian Buildings

PCM briefing: Viking Cold is finalist for innovation award; Sonoco launches sustainable packaging initiative

Ben Welter - Friday, September 20, 2019

Viking Cold Solutions is a finalist for an Energy Storage of North America Innovation Award. The behind-the-meter thermal energy storage systems up for the award are part of an Eversource demand management program in Massachusetts. 

A thermal storage project in Northamptonshire, England, is expected to provide 47 new homes with hot water and heat via renewable energy sources such as solar power. The borehole technology, developed by Caplin Solar of Leicester, stores heat in the ground in warmer months for later use in colder periods.

• Packaging giant Sonoco of Hartsville, S.C., has announced the creation of its EnviroSense sustainable packaging initiative. EnviroSense products are designed to incorporate a number of elements associated with more sustainable packaging, including optimized package-to-product ratio; increased use of recycled and recyclable content; fiber sourcing; compostability; and the use of bio-based materials.

• Registration is open for Sonoco ThermoSafe's next Leading Minds Seminar, "Collaborative Learning that FUELS Your Temperature Sensitive Healthcare Products," to be held Nov. 14 in Amsterdam. The seminar is designed for European supply chain, logistics, quality and packaging professionals responsible for the protection and management of temperature sensitive healthcare clinical supplies and finished products. 

Hydrostor, a Canadian developer of advanced compressed air energy storage projects, has announced the closing of $37 million (USD) in growth financing. Hydrostor has three projects in operation or under construction in Canada and Australia 

• A projected tripling of heat-related deaths in the United Kingdom over the next 30 years will require a drastic rethinking of ways to cool buildings, a parliamentary select committee warns. “The risk of overheating in terms of minimising risks to health and safety of occupants should be enshrined into regulations for new build homes and retrofits," the Environmental Audit Committee said. "This should be considered alongside an integrated review of energy efficiency and ventilation, and be included in the government’s planned Future Homes Standard, to include improvement in the measurement of current and future overheating risk and prioritise passive cooling measures.”

• The most entertaining obituary of a self-taught chemist you will read this month. Rest in peace, Joe Heller.

PCM briefing: Glacier Tek sponsors wheelchair cyclists in Kenya fundraiser; CCT closer to commercializing silicon battery

Ben Welter - Monday, September 09, 2019

Dom Coleman, Regain trustee and grants officerGlacier Tek LLC of Minneapolis is sponsoring seven quadriplegic cyclists taking part in a fundraising ride in Kenya's Rift Valley next month. The Kenya Cycle Challenge 2019, organized by Regain, a U.K.-registered charity, is on track to raise 80,000 pounds to support quadriplegic athletes in Great Britain. More than 50 riders are expected to participate. The seven sponsored riders will be wearing PureTemp-powered Glacier Tek cooling vests to help them handle the 32º C heat they will likely encounter on the five-day ride. People with spinal cord injuries are vulnerable to heat stress because their bodies cannot send the signals needed to initiate sweating in response to hot conditions. 

• Heat battery manufacturer Sunamp Ltd. is among the exhibitors at the InstallerSCOTLAND trade show in Glasgow, Scotland, on Thursday.

CCT Energy Storage is on track to install its first commercial thermal energy device at a mobile phone base station in Adelaide, South Australia, before the end of the year following an agreement in principle with an Australian infrastructure provider. CCT unveiled its first 24kW device in March, describing it as the world’s first working thermal battery using silicon as a phase change material.  

• Hundreds of Australia’s most environmentally advanced homes will open their doors to visitors on Sunday, Sustainable House Day 2019. At least two of the homes – Farrell’s House in Narara, New South Wales, and the 10 Star Home in Cape Paterson, Victoria – feature phase change technology. More than 33,000 people visited 226 homes across Australia last year.  

Patent application: Regenerative solid-solid phase change cooling for an energy storage device

Ben Welter - Monday, September 09, 2019

U.S. patent application 20190273295 (applicant Anhui Xinen Technology Co. Ltd., Anqing Anhui, China):

"Disclosed is a technique for managing the temperature of rechargeable cells. An energy storage device can include a plurality of rechargeable cells disposed within a housing and a material disposed within the housing so as to completely surround each of the rechargeable cells in a particular plane. The material can have a thermal characteristic such that the material remains a solid upon absorbing heat from the rechargeable cells by changing a crystal lattice structure. Intrinsic latent heat properties of the material result in absorption or release of heat to maintain a temperature of a rechargeable cell within a pre-defined temperature range. A regenerative mechanism including a heat pump coil can restore the material to a lower energy crystal lattice structure."

Research roundup: Corrosion effect of Micronal PCMs; photovoltaic-thermal system optimization; diatomite-based composite; more

Ben Welter - Monday, September 09, 2019

From Renewable Energy and Sustainable Buildings:

Study of Corrosion Effect of Micronal® Phase Change Materials (PCM) with Different Metal Samples
Use of Phase Change Materials for Solar Systems Applications
Performance Optimization of Concentrated Photovoltaic-Thermal (CPV-T) System Employing Phase Change Material (PCM) in Hot Climate

From Asia International Symposium on Mechatronics:

Investigation for a Phase Change Immersion Cooling System

From Energy Conversion and Management:

Experimental study of active phase change cooling technique based on porous media for photovoltaic thermal management and efficiency enhancement

From Renewable Energy:

Enhanced properties of diatomite-based composite phase change materials for thermal energy storage
Hybrid thermal energy storage with phase change materials for solar domestic hot water applications: Direct versus indirect heat exchange systems

From Journal of Applied Polymer Science:

Surface modification of MWCNT and its influence on properties of paraffin/MWCNT nanocomposites as phase change material

From Energy and Buildings:

Energy and emissions analysis of ice thermal energy storage in the western US
Thermal energy storage characterization of cementitious composites made with Recycled Brick Aggregates containing PCM

From Solar Energy:

Innovative passive heat-storage walls improve thermal performance and energy efficiency in Chinese solar greenhouses for non-arable lands

From Construction and Building Materials:

Development of structural thermal energy storage concrete using paraffin intruded lightweight aggregate with nano-refined modified encapsulation paste layer

From Applied Energy:

A comprehensive review on positive cold energy storage technologies and applications in air conditioning with phase change materials

From International Journal of Energy Research:

Preparation and characterization of nano‐enhanced myristic acid using metal oxide nanoparticles for thermal energy storage
Performance comparison of different combined heat and compressed air energy storage systems integrated with organic Rankine cycle

From xPRESS Polymer Letters:

Editorial corner – a personal view / Thermal management with polymer composites

From International Symposium on Asphalt Pavement & Environment:

Impregnation of Lightweight Aggregate Particles with Phase Change Material for Its Use in Asphalt Mixtures

From Journal of Sol-Gel Science and Technology:

Development of new inorganic shape stabilized phase change materials with LiNO3 and LiCl salts by sol-gel method

From Advanced Functional Materials:

Functional Soft Composites As Thermal Protecting Substrates for Wearable Electronics

PureTemp shows energy-saving potential in EnergyPlus simulations

Ben Welter - Wednesday, August 28, 2019

In EnergyPlus simulations using hysteresis data, the integration of PureTemp phase change materials in a building's suspended ceiling tiles showed potential savings in cooling energy ranging from 5.5 percent to 37.4 percent.

Ceiling tile drawingThe PCM modeling research, conducted at University of Manitoba, also found a reduction in "discomfort hours" from 10 percent to 29 percent, depending on the zone and PCM type.

The researchers set out to investigate the feasibility of integrating PCMs within a suspended ceiling using the hysteresis method in EnergyPlus 8.9. The hysteresis effect, wherein a PCM has different melting/freezing temperature curves, complicates the simulation of PCM use in buildings. The EnergyPlus modeling software was updated in 2017 to include the effect of hysteresis.

Minneapolis-based PureTemp LLC provided the researchers with the thermo-physical properties of PCMs required for modeling in EnergyPlus. Five types of PCMs, namely PCM20 (PureTemp 20), PCM21, PCM22, PCM23 (PureTemp 23), and PCM24, were tested and analyzed. The melting and freezing temperatures of the five PCMs fall within the thermal comfort range and operation of the HVAC system of the building the researchers chose as a case study: the University of Manitoba's new Stanley Pauley Engineering Building.

Miroslava KavgicThe number of each PCM represents the material's peak melting temperature in degrees Celsius. The theoretical properties of PCM21, PCM22 and PCM24 were derived from the actual properties of PureTemp 20, PureTemp 23 and PureTemp 25.

One of the study's authors, Dr. Miroslava Kavgic, right, is an assistant professor of civil engineering at the university. She answered questions about the research by email.

Q: What do you think is the most important finding, as far as impact on manufacturers of PCMs and PCM products?

A: "The findings of our research study suggest a promising future for the applications of PCMs in buildings located in cold climates. Furthermore, our study showed that in addition to already proven cooling energy-saving potential, PCMs can be very efficient in reducing heating energy demand. As a result, the findings from our study can increase application of PCMs in buildings located in the dominant heating climates, and therefore increase the demand for these unique building materials. We also hope that higher demand for PCMs will bring down their price which currently hinders the more extensive application of PCMs in areas with the lower energy prices such as Manitoba."

Q: Why did you choose to use PureTemp data? Was there a preference to use a biobased PCM? Or was data on other products hard to obtain?

EnergyPlus model: enthalpy-temperature method
EnergyPlus PCM model, enthalpy-temperature method
A: "PureTemp shares valuable thermo-physical properties of its PCM products on its website. Furthermore, upon our request PureTemp provided additional information required for the modeling of PCMs in EnergyPlus using hysteresis method. PureTemp also provides other useful information related to various applications and experimental testing of PCMs. Finally, PureTemp’s PCM products are produced from agricultural sources, and they are readily biodegradable and non-toxic. These positive characteristics of the PureTemp’s PCM products can enable the development of environmentally friendly solutions that can significantly reduce buildings’ energy consumption while improving their indoor thermal comfort."

Q: Given the impact of a PCMs hysteresis the final simulation results, is there a standard you’d like the industry to establish for consistent data from the PCM manufacturers?

EnergyPlus model: hysteresis method
EnergyPlus PCM model, hysteresis method

A: "Consistent data from the PCM manufacturers would increase confidence in the modeling results, and this applies to both hysteresis and temperature-enthalpy methods. Moreover, the consistent PCM properties could also be beneficial for the manufacturers as they will allow the end-user to test multiple PCMs and purchase several different materials for real-world implementation. This is particularly important considering the need for numerical analysis before the real-world implementation due to both complex behavior of PCMs and their relatively high price. The sensitivity analysis of the hysteresis input parameters suggests that manufacturers should pay partial attention to the parameters that have high impact on the simulation results."

Q: For future work, is there interest in comparing the same PCM measured with different methods, such as T-history and DSC?

A: "The t-history method is relatively inexpensive and straightforward to measure the phase-change enthalpy of PCM products using considerably larger sample sizes compared to DSC, and therefore for non-uniform PCMs it is a good testing alternative to DSC."

Table 3. Thermo-physical properties of the tested PCM:

Hysteresis properties PCM20 PCM21 PCM22 PCM23 PCM24
Latent heat during the entire phase change process (J/kg) 171,000 189,000 208,000 227,000 207,000
Peak melting temperature (°C) 20 21 22 23 24
Peak freezing temperature (°C) 18 19 20 21 22
Liquid-state thermal conductivity (W/(m∙K)) 0.14 0.143 0.146 0.15 0.15
Solid-state thermal conductivity (W/(m∙K)) 0.23 0.236 0.243 0.25 0.25
Liquid-state density (kg/m3) 680 730 780 830 840
Solid-state density (kg/m3) 950 936 923 910 930
Liquid-state specific heat (J/(kg∙K)) 2150 2096 2043 1990 2140
Solid-state specific heat (J/(kg∙K)) 2070 1993 1916 1840 1915


The full version of the paper is available here through the end of September 2019:

Research roundup: Microencapsulated coconut oil; mixed alkanes microcapsules; low-hydration heat cement slurry; more

Ben Welter - Tuesday, August 27, 2019

From Cellulose:

Microencapsulated organic coconut oil as a natural phase change material for thermo-regulating cellulosic fabrics

From Journal of Physics: Conference Series:

Numerical and experimental investigation of melting process in spherical PCM capsule used for low-temperature thermal energy storage systems

From Energy:

Synthesis and characterization of mixed alkanes microcapsules with phase change temperature below ice point for cryogenic thermal energy storage
Preparation of Low Hydration Heat Cement Slurry with Micro-encapsulated Thermal Control Material

From Applied Thermal Engineering:

A Three-Dimensional Numerical Investigation of a Novel Shallow Bore Ground Heat Exchanger Integrated with Phase Change Material

From Polymer Science:

Preparation of Phase Change Microcapsules with Inorganic/Polymer Hybrid Shell Through a “Two-Step” Reaction

From Solar Energy:

Improved thermal energy storage for nearly zero energy buildings with PCM integration

From Thermal Science and Engineering Progress:

A theoretical and experimental study of a TBAB salt hydrate based cold thermal energy storage in an air conditioning system

From Journal of Energy Storage:

A Review of Phase Change Materials for the Thermal Management and Isothermalisation of Lithium-Ion Cells

From Energy Conversion and Management:

Experimental performance evaluation of a novel designed phase change material integrated manifold heat pipe evacuated tube solar collector system

From Renewable and Sustainable Energy Reviews:

Corrosion mechanisms in molten salt thermal energy storage for concentrating solar power

PCM briefing: ThermoSafe introduces new passive shipper; PCM-cooled rail containers hit market in China

Ben Welter - Saturday, August 24, 2019

ThermoSafe Pegasus ULD shipper• Sonoco ThermoSafe has announced the creation of a passive, temperature-controlled container that will be manufactured by AEROTUF of Charleston, S.C. The Pegasus ULD container will use AEROTUF’s patented AeroTHERM composite material technology, along with a gelled phase change material. "The Pegasus ULD will ultimately provide 2-8, CRT, and frozen temperature ranges depending on the PCM used for durations up to and exceeding five days," said Ben VanderPlas, manager of Engineering and Product Management at ThermoSafe, which is based in Arlington Heights, Ill. A launch date for the product has not been announced.

• The Chinese rail company that worked with the UK's University of Birmingham last year to develop a prototype of PCM-based freight container is bringing the concept to market. Hebei-based transport business CRRC Shijiazhuang sold 49 of the containers to a manufacturer in China this month. The low-emissions freight containers keep payloads cold without the need for fuel-generated refrigeration. "We are delighted to see our cold storage technologies start to make the commercial market," said Yulong Ding, director of the Birmingham Centre for Energy Storage. "We are working with our partners to extend the cold storage technologies to more applications."

Lagunitas Phase Change ale• Here's a co-branding opportunity for a PCM manufacturer with a taste for hops: Lagunitas Brewing Co. of Petaluma, Calif., has introduced Phase Change, "an unfiltered, wet-hop ale packed full of lupulin-drenched Simcoe, Citra & Mosaic hops." The brewer describes the beer as "somewhere between a solid and a liquid... a Phase Change of sorts."  

• More than 170 speakers are lined up for the 14th International Conference on Advanced Building Skins, to be held Oct. 28-29 in Bern, Switzerland. The Japanese architect and Pritzker laureate Shigeru Ban will deliver the keynote address. Thomas Friedrich of Innogration GmbH, Germany, will discuss "collection of thermal energy from the façade" and "decentralized PCM storage elements for saving thermal energy." Damien Mathis of Ai Environnement, Paris, will give a presentation on the "thermal performance of engineered wood flooring impregnated with phase-change materials." The registration fee is 680 euros and includes the conference documentation as well as meals during both days. Participants who register by Aug. 30 will receive a 10 percent discount.