Thermal‐Responsive and Fire‐Resistant Materials for High‐Safety Lithium‐Ion Batteries

Abstract

is due to their high specific energy density, long cycling lifespan, and portability. [7][8][9][10] Currently, state-of-the-art LIBs (without packaging materials) can achieve a high specific energy density of ≈250 Wh kg −1 . Next-generation LiS and Li-air systems can further increase the battery energy densities beyond 600 and 900 Wh kg −1 , respectively. [11,12] With the energy density increasing, more attention should be paid to the safety of LIBs, as the chemical energy can be abruptly released in the forms of fires and explosions once the battery is not properly handled. [13][14][15][16][17][18] Currently, the safety issues are also regarded as one of the significant challenging barriers that limit the widespread adoption of LIBs for modern electrical vehicles. [19,20] A typical lithium-ion cell is composed of an anode, a cathode, liquid electrolytes, and a separator, [1] as illustrated in Figure 1A. The active materials are mixed with polymer binders and conductive carbon additives and then coated onto aluminum and copper foil current collectors to make the cathode and anode, respectively. Layered, spinel, and polyanion-type lithium-transitional metal oxides and phosphates including LiCoO 2 , LiMn 2 O 4 , LiFePO 4 , and their derivatives (LiMn x Ni y O 4 , LiNi 1−y−z Mn y Co z O 2 , etc.) have been used as cathode materials for LIBs due to their high lithium intercalation capacity and potential. [5] Graphite is the most frequently used anode material for LIBs because of its high abundance, low cost, and good reversibility. [21,22] Other materials such as carbon, [23] silicon, [24][25][26] and transition metal oxides-based materials with various structures and compositions have been studied as anodes for LIBs. [27][28][29] Some of them show promising capacity but there are still many challenges in scaled-up productions and practical applications. [30,31] For details of studies on structural design and performance optimization of the LIB anode materials, readers may refer to a comprehensive review published recently. [32] The liquid electrolyte provides a medium for fast Li + ions transport. [33,34] The separator is applied to prevent direct contact between the cathode and anode while permitting the ion transfer. [35][36][37][38] During the charging process, Li + ions are deintercalated from the cathode host and insert into the anode. On discharge, Li + ions migrate reversely from the above process, and electrons pass through the external circuit, supplying electricity [1] (Figure 1A). A passivation layer of solid-electrolyte-interphase (SEI) is generated on the anode surface during the initial few charging cycles, As one of the most efficient electrochemical energy storage devices, the energy density of lithium-ion batteries (LIBs) has been extensively improved in the past several decades. However, with increased energy density, the safety risk of LIBs becomes higher too. The frequently occurred battery accidents worldwide remind us that safeness is a crucial requirement for LIBs, especially in environments ...

Thermal-Switchable, Trifunctional Ceramic–Hydrogel Nanocomposites Enable Full-Lifecycle Security in Practical Battery Systems

“…The above strategies were used to mitigate battery thermal safety at a specific level but are limited in comprehensively handling full-lifecycle thermal issues. For example, owing to their capability of absorbing and releasing thermal energy during phase transitions, PCMs have been widely applied to the thermal management of energy storage devices to adjust the temperature to an appropriate range and reduce the risk of TR. , However, once the generated heat exceeds the energy that PCMs can dissipate, a combustible PCM can even accelerate TR propagation. Ceramic aerogel insulation materials are candidates for delaying TR propagation due to their structure stability at high temperatures and intrinsic low thermal conductivity .…”

Revitalizing zinc-ion batteries with advanced zinc anode design

“…6c and d). 27,72,[77][78][79][80] In addition, the relationship between temperature and nucleation can be demonstrated by the inhomogeneous plating caused by the inhomogeneous temperature (local high temperature) inside the cell. Therefore, the design of optimized experimental temperatures based on thermodynamic and kinetic analysis can effectively promote the uniform deposition of metals.…”

Nature‐inspired materials and designs for flexible lithium‐ion batteries

“…Despite the bright future and growing market of flexible batteries, the development of them with high flexibility and excellent battery performances remains extremely challenging 12–15 . Conventional electrochemical energy storage devices are made from rigid and tightly stacked multilayer components, where the electrode materials are easily exfoliated off from the current collectors under mechanical stresses, resulting in deteriorated electrochemical performances, complete failure, and even severe safety problems 16,17 . Thus, the exploration of flexible electrochemical energy storage devices with both excellent electrochemical performance and superior mechanical deformability has become a research hotspot recently 9,18–23 …”

“…[12][13][14][15] Conventional electrochemical energy storage devices are made from rigid and tightly stacked multilayer components, where the electrode materials are easily exfoliated off from the current collectors under mechanical stresses, resulting in deteriorated electrochemical performances, complete failure, and even severe safety problems. 16,17 Thus, the exploration of flexible electrochemical energy storage devices with both excellent electrochemical performance and superior mechanical deformability has become a research hotspot recently. 9,[18][19][20][21][22][23] Among various electrochemical energy storage devices, lithium-based batteries are the primary candidates for serving as power sources for portable electronic devices due to their high energy density, high output voltage, and long cycling lifespan.…”