The integration of electric vehicles (EVs) powered by lithium-ion batteries (LIBs) marks a pivotal phase towards achieving a net-zero environment. The anticipated surge in EV adoption is expected to yield a substantial influx of battery waste in the coming decade. Despite manifold advancements in optimizing Li-ion battery packs, ensuring a sustainable end-of-life strategy still remains an engineering and economic challenge. The diverse pack configurations further complicate efficient disassembly processes. Adhesives play an essential role in mechanical, electrical and thermal management in battery packs, being suitable for cell-to-cell bonding, busbar protection, cooling plate thermal management and sealing. The spectrum of adhesives used encompasses structural, semi-structural, flexible and pressure sensitive, selected based on component operational specifications throughout the service life. This review provides a comprehensive overview of bonding solutions used in commercial EV energy storage systems, with a focus on the feasibility of dismountable adhesives. It scrutinizes the use of adhesives to bond battery pack components, considering the emerging debonding-on-demand trends. Studies assessing adhesive debonding have demonstrated that some formulations are responsive to external stimuli, capable of weakening the adhesive layer or the interface bond. For battery applications, these modified adhesives must neither show property degradation nor experience such trigger mechanics during service, enabling intentional weakening of the adhesive layer when required. Additionally, this article presents concise solutions for adhesive selection in battery packs, drawing from an in-depth analysis of battery assembly and dismantling processes.

The need for more sustainable adhesive formulations has led to the use of silane-based adhesives in different industrial sectors, such as the automotive industry. In this work, the mechanical properties of a dual cure two-component prototype adhesive which combined silylated polyurethane resin (SPUR) with standard epoxy resin was characterized under quasi-static conditions. The characterization process consisted of tensile bulk testing, to determine the Young’s modulus, the tensile strength and the tensile strain to failure. The shear stiffness and shear strength were measured by performing a thick adherend shear test. The in-plane strain field was obtained using a digital image correlation method. Double-cantilever beam and mixed-mode tests were performed to assess the fracture toughness under pure modes. The prototype adhesive showed promising but lower properties compared to commercial solutions. Furthermore, the adhesive was modified via the addition of three different resin modifier additives and characterized via measuring the shear and tensile properties, but no enhancements were found. Finally, the adhesive was formulated with three different SPUR viscosities. The critical energy release rate analysis showed an optimum value for the medium viscosity SPUR adhesive.

Avaliou-se a qualidade da carne de 10 bovinos F1 Guzerá-Nelore e 10 F2 Pardo Suíço-Guzerá-Nelore, inteiros, e abatidos precocemente. Na avaliação da carne, foi utilizado o músculo Longissimus dorsi. O delineamento experimental foi o inteiramente ao acaso. Verificaram-se para F1 e F2, respectivamente, médias para umidade de 75,3 e 75,1, extrato etéreo de 1,4 e 1,5, proteína de 23,7 e 23,6 e cinzas de 1,04 e 1,06. Cor em L* de 28,9 e 30,3, médias para cor em a* de 22,6 e 23,4 e cor em b* de 15,3 15,4, força de cisalhamento de 3,4 e 3,5, perda de peso pelo descongelamento de 9,8 e 10,5 e perda pelo cozimento de 15,9 e 15,6. Não houve diferença estatística para nenhuma das variáveis analisadas entre os grupos genéticos.

A novel hot-melt cyclic olefin-based adhesive was designed as a transparent, non-tacky film of amorphous thermoplastic with a unique polymer micro-structure. The aim of the present paper is to assess the mechanical properties of the 0.1 mm thick COP hot-melt adhesive film through adhesive characterizations tests. The glass transition temperature was determined using dynamic mechanical analysis (DMA). For mechanical characterization, bulk and thick adherend shear specimens were manufactured and tested at a quasi-static rate, where at least three specimens were used to calculate the average and standard deviation values. Tensile tests revealed the effects of molecular chain drawing and reorientation before the onset of strain hardening. Thick adherend shear specimens were used to retrieve shear properties. Fracture behaviour was assessed with the double cantilever beam (DCB) test and end-notched flexure (ENF) test, for characterization under modes I and II, respectively. To study the in-joint behaviour, single lap joints (SLJs) of aluminium and carbon fibre-reinforced polymer (CFRP) were manufactured and tested under different temperatures. Results showed a progressive interfacial failure following adhesive plasticization, allowing deformation prior to failure at 8 MPa. An adhesive failure mode was confirmed through scanning electron microscopy (SEM) analysis of aluminium SLJ. The adhesive exhibits tensile properties comparable to existing adhesives, while demonstrating enhanced lap shear strength and a distinctive failure mechanism. These characteristics suggest potential advantages in applications involving heat and pressure across automotive, electronics and structural bonding sectors.

The rise in electric vehicles (EVs) with lithium-ion batteries supports net-zero goals, but the increasing demand will inevitably generate more battery waste. Current pack designs often rely on permanent joining techniques, which hinder disassembly and thereby limit serviceability, reuse and recycling. A critical challenge is the removal of the battery lid, typically bonded to the pack frame with sealant adhesives. In the absence of design for disassembly requirements for OEMs, this study investigates a novel debonding strategy focused on the lid-to-frame bonding. A silane-based adhesive commonly used in battery packs is first characterised under tensile, shear and mode I conditions to establish the baseline performance in the range of flexible adhesive properties. Herein, a heat-activated primer is introduced as a debondable interfacial layer between the adhesive and the substrate. Upon activation at 150 °C, the primer significantly reduces adhesion, around 98% of the initial joint strength, enabling room temperature debonding. The primer demonstrates strong compatibility with epoxy and polyurethane adhesives, but its performance with silane-based systems still needs to be improved in terms of the primer’s compatibility with silane-based adhesives. Finally, a small-scale testing apparatus is developed to evaluate primer effectiveness in the disassembly of battery lids. This approach represents a promising step toward more serviceable, recyclable and sustainable battery systems.

This study presents a comprehensive mechanical characterisation of a novel, transparent, amorphous thermoplastic hot-melt adhesive (HMA) film, based on a cyclo olefin polymer, engineered for applications in the automotive, electronics and semi-structural bonding sectors. Quasi-static tensile tests reveal typical thermoplastic behaviour, cold drawing followed by strain hardening, with a Young's modulus of 230 MPa, a tensile strength of 11 MPa and an exceptional elongation at break of 1000%. Thick adherend shear tests (TAST) yield a shear strength of 5 MPa. Fracture behaviour was investigated under Mode I and Mode II loading. Double cantilever beam (DCB) tests on CFRP substrates provide an apparent Mode I fracture energy of 0.43 N/mm. Despite minor substrate rotation and stretching effects, the results indicate a predominantly ductile response of the adhesive layer. End-notched flexure (ENF) tests reveal more complex Mode II behaviour: an initial peak fracture energy of 2.6 N/mm is obtained after a sustained plateau near 0.5 N/mm, interpreted as the onset of permanent plastic damage. This plateau, uncommon in comparable thermoplastic adhesives, suggests a progressive transition from brittle to ductile failure and consistently coincides with adhesive failure at the interface. Dynamic mechanical analysis (DMA) identifies a glass transition temperature of 88°C. Collectively, these results demonstrate that the material offers strong potential for applications requiring thermal resistance and pressure-tolerant bonding, though enhancements in interfacial adhesion are needed to fully optimize performance.