Thermal Management in Electrochemical Energy Storage Systems

Abstract

With growing energy demands and the looming depletion of fossil fuels, electrochemical energy conversion and storage systems are under aggressive development for current and future renewable energy needs [1]. Hybrid electric vehicles (HEVs), combining two power sources-internal combustion engines and electric motors in order to achieve better performance, are already common. The major types of electrochemical storage system are batteries, capacitors, fuel cells, and their combinations. The prime performance metrics for comparing these technologies are reliability, power and energy density, cycle-life, temperature range and emission of pollutants. Batteries and capacitors are closed systems with anodes, cathodes and separators that are soaked with electrolytes and sealed in a single compartment. Conversely in fuel cells, the fuel, consisting of hydrogen at the anode and oxygen at the cathode, is supplied from a tank. Figure 1.1 provides a Ragone plot that compares different electrochemical energy storage systems to internal combustion engines and turbines, and electrolytic capacitors. As apparent from the simplified Ragone plot, supercapacitors bridge the gap between conventional electrolytic capacitors and batteries in terms of specific energy and power densities. The terms specific energy (in Wh kg −1 ) and energy density in (Wh L −1 ) are generally used to assess energy storage systems, whereas their rate capability is represented by specific power (in W kg −1 ) or power density (in W L −1 ). Thermal management of energy storage systems is essential for their high performance over suitably wide temperature ranges. At low temperatures, performance decays mainly because of the low ionic conductivity of the electrolyte; while at high temperatures, the components tend to age due to a series of side reactions, causing safety and reliability issues [2]. Therefore, trade-offs exist among system performance, functionality, design, cost, maintenance, and safety. Optimization of these parameters to achieve high performance of power supplies requires fundamental and thorough understanding of thermal transport in the systems. This chapter provides a brief introduction to thermal management in major electrochemical energy storage systems.

Emergence of Novel 2D Materials for High-Performance Supercapacitor Electrode Applications: A Brief Review

“…This electrode−electrolyte interface resembles a conventional capacitor, consisting of two conducting plates separated by an insulator. 7,15,16 Conventionally, the capacitance (C) can be defined as the ratio of stored charge (Q) to the voltage applied (V) or proportional to the conducting plate area (A) and the plate separation (d). 17 Supercapacitors are called "super" because they differ from electrolytic capacitors.…”

“…4,16 These factors increase the capacitance by keeping low equivalent series resistance (ESR), where ESR represents the ohmic losses accompanying resistance at the electrode surface, electrical contacts, and electrolyte resistance. 18,19,16 Energy density is the ability of the supercapacitor to store energy. The amount of energy stored in a supercapacitor depends on its capacitance (C) and charging potential (V), as expressed in eq 2 7,20…”

Synthesis of Porous Ni–Co–Mn Oxide Nanoneedles and the Temperature Dependence of Their Pseudocapacitive Behavior

“…Interactions between electrodes and electrolytes at high/low temperatures may affect the subsequent performance at RT (e.g., cycling to/from high or low temperatures) (Xiong et al, 2015b). The thermal stability and repeatability of the Ni-Co-Mn oxide electrodes has also been demonstrated by characterizing them at RT, after being tested at 80°C (see Figure S10 in Supplementary Material).…”

“…Stable electrochemical performance of supercapacitors over a wide range of temperatures is also essential to their applications in harsh environments and extreme conditions. Among the supercapacitor components, electrode materials can have a strong influence on the thermal performance of supercapacitors (Xiong et al, 2015b).…”

Effect of polymer sulfonation on the proton conductivity and fuel cell performance of polyvinylalcohol‐mordenite direct methanol fuel cell membranes

“…Unlike regular batteries such as Li‐ion batteries, fuel cells are thermodynamically open systems. In other words, the fuel and oxidant are continuously fed into a fuel cell as it operates, leading to a much‐increased operational lifespan when compared with regular batteries . However, just like regular batteries, fuel cells contain an anode and a cathode electrode, in which oxidation and reduction reactions take place, respectively.…”