The environmental impact of disposable versus re-chargeable batteries for consumer use

Goal, Scope and Background The most common system for powering small items of electronics by both consumers and industry in Australia is simply to repeatedly buy and use disposable alkaline batteries. A growing practice however is to invest in a small battery charger and buy more expensive rechargeables such as nickel metal hydride batteries. This latter course is promoted as being better for the environment. This study evaluates this assertion to guide future practice by both consumers and industry. The study compares re-chargeable AA batteries of both nickel cadmium (NiCd) and nickel metal hydride (NiMH) chemistry, each used either 400 times or 50 times with the number of AA alkaline batteries required to provide 1 kWh of energy to a device being powered. The scope of the analysis includes the materials and processes used in the production, distribution, use and disposal of the batteries and the battery charger and includes consideration of partial recycling and disposal to landfill. Methods The study is done by developing an inventory of the life cycle of each of the alternatives which in the case of re-chargeable batteries includes the charger and the discharge & re-charging process. Measurements were conducted of re-charging efficiencies of representative batteries and of battery charger energy efficiencies. Energy use in wholesale and retail parts of the distribution system are also accounted for. Sima Pro LCA software and associated Australian data bases are then used to analyse the data using the Eco Indicator 99 (E) model of environmental impact. Results The relative impacts of the three alternative systems on the categories human health, ecosystem quality and resource use showed little difference between the NiCd and NiMH batteries except for human health where the toxicity of cadmium gave a 20% advantage to NiMH batteries. When comparing rechargeable batteries with alkaline batteries, the former caused less damage by factors varying from 10 to 131 for an optimistic scenario of 400 cycles of discharge and charge. Significant factors in the impact of the re-chargeable batteries were the production of batteries themselves, the electricity used for whole saling and retailing, the transport to landfill and the copper and other components in the battery charger. For the disposable alkaline batteries the dominant impacts came from the electrical energy used for wholesaling and retailing the batteries, followed by the production of the batteries. Discussion Most of the results are in line with expectations but somewhat surprisingly, the impact in most categories is dominated by the energy used in wholesaling and retailing, particularly for the alkaline batteries where the number involved is large. Also surprising is the fact that the cadmium present in the NiCd batteries was less significant than many other factors. The results however agree broadly with those of Lankey and McMichael (2000). Conclusions Analysis results were overwhelmingly in favour of the re-chargeable battery option. This was true for every impact criteria studied and for less than optimistic scenarios of battery use such as significant shelf life or high discharge rates. Recommen dations and Perspectives Given the present very large market for disposable batteries in Australia, there is a need for education of the consumer population and, to a lesser extent, industry, of the environmental and economic advantages of moving to re-chargeable batteries. ESS-Submission Editor: Dr. Wulf-Peter Schmidt (wschmi18@ford.com)     

A Total Organic Aqueous Redox Flow Battery Employing a Low Cost and Sustainable Methyl Viologen Anolyte and 4‐HO‐TEMPO Catholyte

Increasing worldwide energy demands and rising CO₂ emissions have motivated a search for new technologies to take advantage of renewables such as solar and wind energies. Redox flow batteries (RFBs) with their high power density, high energy efficiency, scalability (up to MW and MWh), and safety features are one suitable option for integrating such energy sources and overcoming their intermittency. However, resource limitation and high system costs of current RFB technologies impede wide implementation. Here, a total organic aqueous redox flow battery (OARFB) is reported, using low‐cost and sustainable methyl viologen (MV, anolyte) and 4‐hydroxy‐2,2,6,6‐tetramethylpiperidin‐1‐oxyl (4‐HO‐TEMPO, catholyte), and benign NaCl supporting electrolyte. The electrochemical properties of the organic redox active materials are studied using cyclic voltammetry and rotating disk electrode voltammetry. The MV/4‐HO‐TEMPO ARFB has an exceptionally high cell voltage, 1.25 V. Prototypes of the organic ARFB can be operated at high current densities ranging from 20 to 100 mA cm², and deliver stable capacity for 100 cycles with nearly 100% Coulombic efficiency. The MV/4‐HO‐TEMPO ARFB displays attractive technical merits and thus represents a major advance in ARFBs.     

Insight into Prolonged Cycling Life of 4 V All-Solid-State Polymer Batteries by a High-Voltage Stable Binder

Polyethylene oxide (PEO) based solid polymer electrolytes (SPEs) are incompatible with the 4 V class cathodes such as LiCoO₂ due to the limited electrochemical oxidation window of PEO. Herein, a number of binders including commonly used binders PEO, polyvinylidene fluoride (PVDF), and carboxyl-rich polymer (CRP) binders such as sodium alginate (Na-alginate) and sodium carboxymethyl cellulose, are studied for application in the 4 V class all-solid-state polymer batteries (ASSPBs). The results show ASSPBs with CRP binders exhibit superior cycling performance up to 1000 cycles (60% capacity retention, almost 10 times higher than those with PEO and PVDF binders). Synchrotron-based X-ray absorption spectroscopy (XAS), morphology studies and density functional theory studies indicate that, with their carboxyl groups, CRPs can strongly bind the electrode materials together, and work as coating materials to protect the cathode/SPE interface. Cyclic voltammetry studies indicate that CRP binders are more stable at high voltage compared to PEO and PVDF. The stability under high voltage and the coating property of CRP binders contribute to stable cathode/SPE interfaces as disclosed by the X-ray photoelectron spectroscopy and Co L-edge XAS results, enabling long cycling life, high performance 4 V class ASSPBs.     

3D Printable Ceramic–Polymer Electrolytes for Flexible High‐Performance Li‐Ion Batteries with Enhanced Thermal Stability

This study establishes an approach to 3D print Li‐ion battery electrolytes with controlled porosity using a dry phase inversion method. This ink formulation utilizes poly(vinyldene fluoride) in a mixture of N‐methyl‐2‐pyrrolidone (good solvent) and glycerol (weak nonsolvent) to generate porosity during a simple drying step. When a nanosized Al₂O₃ filler is included in the ink, uniform sub‐micrometer pore formation is attained. In other words, no additional processing steps such as coagulation baths, stretching, or etching are required for full functionality of the electrolyte, which makes it a viable candidate to enable completely additively manufactured Li‐ion batteries. Compared to commercial polyolefin separators, these electrolytes demonstrate comparable high rate electrochemical performance (e.g., 5 C), but possess better wetting characteristics and enhanced thermal stability. Additionally, this dry phase inversion method can be extended to printable composite electrodes, yielding enhanced flexibility and electrochemical performance over electrodes prepared with only good solvent. Finally, sequentially printing this electrolyte ink over a composite electrode via a direct write extrusion technique has been demonstrated while maintaining expected functionality in both layers. These ink formulations are an enabling step toward completely printed batteries and can allow direct integration of a flexible power source in restricted device areas or on nonplanar surfaces.     

Two‐Dimensional Materials for Beyond‐Lithium‐Ion Batteries

Lithium‐ion batteries (LIBs) have dominated the portable electronics industry and solid‐state electrochemical research and development for the past two decades. In light of possible concerns over the cost and future availability of lithium, sodium‐ion batteries (SIBs) and other new technologies have emerged as candidates for large‐scale stationary energy storage. Research in these technologies has increased dramatically with a focus on the development of new materials for both the positive and negative electrodes that can enhance the cycling stability, rate capability, and energy density. Two‐dimensional (2D) materials are showing promise for many energy‐related applications and particularly for energy storage, because of the efficient ion transport between the layers and the large surface areas available for improved ion adsorption and faster surface redox reactions. Recent research highlights on the use of 2D materials in these future ‘beyond‐lithium‐ion’ battery systems are reviewed, and strategies to address challenges are discussed as well as their prospects.     

Theoretical versus Practical Energy: A Plea for More Transparency in the Energy Calculation of Different Rechargeable Battery Systems

Electrochemical energy storage at a large scale poses one of the main technological challenges of this century. The scientific community in academia and industry worldwide intensively is exploring various alternative rechargeable battery concepts beside state‐of‐the‐art lithium ion batteries (LIBs), for example, all‐solid‐state batteries, lithium/sulfur batteries, magnesium/sulfur batteries or dual‐ion batteries that could outperform LIBs in different aspects. Often, these concepts also promise very high theoretical energies per mass or volume. However, as theoretical values exclude numerous relevant parameters, they do not translate directly into practically achievable energy values: The gaps between practical capacities and voltages compared to the theoretical values differ for each system. In order to provide high transparency and to illustrate which cell components are most important in the limitation of the practical energy values, in this study, the specific energies and energy densities are calculated in six subsequent steps—from the theoretical energy values of the active materials alone to the practical energy values in an 18650 cylindrical cell. By providing a tool to calculate the energy values of six different battery technologies with different assumptions made evident, this study aims for more transparency and reliability in the comparison of different cell chemistries.     

Covalent–Organic Frameworks: Advanced Organic Electrode Materials for Rechargeable Batteries

Covalent–organic frameworks (COFs), featuring structural diversity, framework tunability and functional versatility, have emerged as promising organic electrode materials for rechargeable batteries and garnered tremendous attention in recent years. The adjustable pore configuration, coupled with the functionalization of frameworks through pre‐ and post‐synthesis strategies, enables a precise customization of COFs, which provides a novel perspective to deepen the understanding of the fundamental problems of organic electrode materials. In this review, a summary of the recent research into COFs electrode materials for rechargeable batteries including lithium‐ion batteries, sodium‐ion batteries, potassium‐ion batteries, and aqueous zinc batteries is provided. In addition, this review will also cover the working principles, advantages and challenges, strategies to improve electrochemical performance, and applications of COFs in rechargeable batteries.     

Hollow Carbon Spheres and Their Hybrid Nanomaterials in Electrochemical Energy Storage

Electrochemical energy storage is of extraordinary importance for fulfilling the utilization of renewable and sustainable energy sources. There is an increasing demand for energy storage devices with high energy and power densities, prolonged stability, safety, and low cost. In the past decade, numerous research efforts have been devoted to achieving these requirements, especially in the design of advanced electrode materials. Hollow carbon spheres (HCS) derived nanomaterials combining the advantages of 3D HCS and porous structures have been considered as alternative electrode materials for advanced energy storage applications, due to their unique features such as high surface‐to‐volume ratios, encapsulation capability, together with outstanding chemical and thermal stability. In this review, the authors first present a comprehensive overview of the synthetic strategies of HCS, and elucidate the design and synthesis of HCS‐derived nanomaterials including various types of HCS and their nanohybrids. Additionally, their significant roles as electrode materials for supercapacitors, lithium‐ion or sodium‐ion batteries, and sulfur hosts for lithium sulfur batteries are highlighted. Finally, current challenges in the synthesis of HCS and future directions in HCS‐derived nanomaterials for energy storage applications are proposed.     

Side by Side Battery Technologies with Lithium‐Ion Based Batteries

In recent years, the electrochemical power sources community has launched massive research programs, conferences, and workshops on the “post Li battery era.” However, in this report it is shown that the quest for post Li‐ion and Li battery technologies is incorrect in its essence. This is the outcome of a three day discussion on the future technologies that could provide an answer to a question that many ask these days: Which are the technologies that can be regarded as alternative to Li‐ion batteries? The answer to this question is a rather surprising one: Li‐ion battery technology will be here for many years to come, and therefore the use of “post Li‐ion” battery technologies would be misleading. However, there are applications with needs for which Li‐ion batteries will not be able to provide complete technological solutions, as well as lower cost and sustainability. In these specific cases, other battery technologies will play a key role. Here, the term “side‐by‐side technologies” is coined alongside a discussion of its meaning. The progress report does not cover the topic of Li‐metal battery technologies, but covers the technologies of sodium‐ion, multivalent, metal–air, and flow batteries.     

All‐Solid‐State,Foldable, and Rechargeable Zn‐Air Batteries Based on Manganese Oxide Grown on Graphene‐Coated Carbon Cloth Air Cathode

Pliable, safe, and inexpensive energy storage devices are in demand to power modern flexible electronics. In this work, a foldable battery based on a solid‐state and rechargeable Zn‐air battery is introduced. The air cathode is prepared by coating graphene flakes on pretreated carbon cloth to form a dense, interconnected, and conducting carbon network. Manganese oxide hierarchical nanostructures are subsequently grown on the large surface area carbon network, leading to high loading of active catalyst per unit volume while maintaining the mechanical and electrical integrity of the air cathode. Solid‐state and rechargeable Zn‐air battery with such air cathode exhibits similar polarization curve and resistance at its flat and folded states. The folded battery is able to deliver a power density as high as ≈32 mW cm^?2 and good cycling stability of up to 110 cycles. In addition, the flat battery shows similar discharge/charge curve and stable cycling performance after 100 times of repeated folding and unfolding, indicating its high mechanical robustness.     

Sulfide Solid Electrolytes for Lithium Battery Applications

The use of solid electrolytes is a promising direction to improve the energy density of lithium‐ion batteries. However, the low ionic conductivity of many solid electrolytes currently hinders the performance of solid‐state batteries. Sulfide solid electrolytes can be processed in a number of forms (glass, glass‐ceramic, and crystalline) and have a wide range of available chemistries. Crystalline sulfide materials demonstrate ionic conductivity on par with those of liquid electrolytes through the utilization of near ideal conduction pathways. Low‐temperature processing is also possible for these materials due to their favorable mechanical properties. The main drawback of sulfide solid electrolytes remains their electrochemical stability, but this can be addressed through compositional tuning or the use of artificial solid electrolyte interphase (SEI). Implementation of sulfide solid electrolytes, with proper treatment for stability, can lead to substantial improvements in solid‐state battery performance leading to significant advancement in electric vehicle technology.     

Comprehensive New Insights and Perspectives into Ti‐Based Anodes for Next‐Generation Alkaline Metal (Na+, K+) Ion Batteries

Sodium ion batteries (NIBs) and potassium ion batteries (KIBs) are promising candidates for large‐scale energy storage systems, with a similar “rocking chair” working principle to lithium ion batteries due to their earth abundance and lower cost. One of the major challenges in NIB research is the search for suitable anode materials with long lifetimes and high specific capacities. The research on KIBs is still in its infancy. Titanium‐based anodes present low lattice strain, high safety, and overall stability during cycling, which make them promising for large‐scale systems, especially for stationary batteries. In this review, the latest progress on titanium‐based anodes for NIBs and KIBs is summarized, including titanium dioxide and its composite, Na _x TiO₂ systems, NaTi₂(PO₄)₃, titanates, and MXenes. The synthesis methods, modification methods, and sodium or potassium ion storage mechanisms of titanium‐based anodes are detailed; also the current challenges and future opportunities are discussed.     

Metal‐Air Batteries: Metal–Air Batteries with High Energy Density: Li–Air versus Zn–Air (Adv. Energy Mater. 1/2011)

In the past decade, there have been exciting developments in the field of lithium ion batteries as energy storage devices, resulting in the application of lithium ion batteries in areas ranging from small portable electric devices to large power systems such as hybrid electric vehicles. However, the maximum energy density of current lithium ion batteries having topatactic chemistry is not sufficient to meet the demands of new markets in such areas as electric vehicles. Therefore, new electrochemical systems with higher energy densities are being sought, and metal‐air batteries with conversion chemistry are considered a promising candidate. More recently, promising electrochemical performance has driven much research interest in Li‐air and Zn‐air batteries. This review provides an overview of the fundamentals and recent progress in the area of Li‐air and Zn‐air batteries, with the aim of providing a better understanding of the new electrochemical systems.     

Metal–Air Batteries with High Energy Density: Li–Air versus Zn–Air

In the past decade, there have been exciting developments in the field of lithium ion batteries as energy storage devices, resulting in the application of lithium ion batteries in areas ranging from small portable electric devices to large power systems such as hybrid electric vehicles. However, the maximum energy density of current lithium ion batteries having topatactic chemistry is not sufficient to meet the demands of new markets in such areas as electric vehicles. Therefore, new electrochemical systems with higher energy densities are being sought, and metal‐air batteries with conversion chemistry are considered a promising candidate. More recently, promising electrochemical performance has driven much research interest in Li‐air and Zn‐air batteries. This review provides an overview of the fundamentals and recent progress in the area of Li‐air and Zn‐air batteries, with the aim of providing a better understanding of the new electrochemical systems.     

Solid Oxide Fuel Cells: Microstructure of Nanoscaled La0.6Sr0.4CoO3‐δ Cathodes for Intermediate‐Temperature Solid Oxide Fuel Cells (Adv. Energy Mater. 2/2011)

Nanocrystalline La_1‐xSr_xCoO_3‐δ (LSC) thin films with a nominal Sr‐content of x = 0.4 were deposited on Ce_0.9Gd_0.1O_1.95 electrolyte substrates using a low temperature sol‐gel process. The structural and chemical properties of the LSC thin films were studied after thermal treatment, which included a calcination step and a variable, extended annealing time at 700 °C or 800 °C. Transmission electron microscopy combined with selected‐area electron diffraction, energy‐dispersive X‐ray spectrometry, and scanning transmission electron microscopy tomography was applied for the investigation of grain size, porosity, microstructure, and analysis of the local chemical composition and element distribution on the nanoscale. The area specific resistance (ASR) values of the thin film LSC cathodes, which include the lowest ASR value reported so far (ASR_chem = 0.023 Ωcm² at 600 °C) can be interpreted on the basis of the structural and chemical characterization.     

Incorporating Solvate and Solid Electrolytes for All‐Solid‐State Li2S Batteries with High Capacity and Long Cycle Life

The development of all‐solid‐state lithium–sulfur batteries is hindered by the poor interfacial properties at solid electrolyte (SE)/electrode interfaces. The interface is modified by employing the highly concentrated solvate electrolyte, (MeCN)₂?LiTFSI:TTE, as an interlayer material at the electrolyte/electrode interfaces. The incorporation of an interlayer significantly improves the cycling performance of solid‐state Li₂S batteries compared to the bare counterpart, exhibiting a specific capacity of 760 mAh g^?1 at cycle 100 (330 mAh g^?1 for the bare cell). Electrochemical impedance spectroscopy shows that the interfacial resistance of the interlayer‐modified cell gradually decreases as a function of cycle number, while the impedance of the bare cell remains almost constant. Cross‐section scanning electron microscopy (SEM)/ energy dispersive X‐ray spectroscopy (EDS) measurements on the interlayer‐modified cell confirm the permeation of solvate into the cathode and the SE with electrochemical cycling, which is related to the decrease in cell impedance. In order to mimic the full permeation of the solvate across the entire cell, the solvate is directly mixed with the SE to form a “solvSEM” electrolyte. The hybrid Li₂S cell using a solvSEM electrolyte exhibits superior cycling performance compared to the solid‐state cells, in terms of Li₂S loading, Li₂S utilization, and cycling stability. The improved performance is due to the favorable ionic contact at the battery interfaces.     

A Metal‐Free and Biotically Degradable Battery for Portable Single‐Use Applications

This article presents a new approach for environmentally benign, low‐cost batteries intended for single‐use applications. The proposed battery is designed and fabricated using exclusively organic materials such as cellulose, carbon, and wax and features an integrated quinone‐based redox chemistry to generate electricity within a compact form factor. This primary capillary flow battery is activated by the addition of a liquid sample and has shown continuous operation up to 100 min with an output voltage that can be conveniently scaled to match the voltage needs of portable electronic devices (1.5–3.0 V). Once depleted, the battery can be disposed of without the need for any recycling facility, as its components are nontoxic and shown to be biotically degradable in a standardized test. The practical utility of the battery is demonstrated by direct substitution of a lithium ion coin cell in a diagnostic application.     

Integrated Configuration Design for Ultrafast Rechargeable Dual‐Ion Battery

In this work, an integrated dual‐ion battery design is reported with active materials, current collectors, and separator, assembled in one flexible component. An aluminum film is deposited directly onto one side of the 3D porous glass fiber separator to form a porous anode. Cathode active materials are loaded on the other side of the separator with aluminum film deposited on the top as current collector. This design demonstrates ultrafast charge/discharge rate up to 120 C while maintaining high capacity of 116.1 mA h g^?1. Moreover, long‐term stability of over 1500 cycles at a high rate of 60 C is achieved. The estimated energy density remains as high as 232.6 W h kg^?1 at an ultrahigh power density of 22634.5 W kg^?1.